This document discusses superficial mycoses caused by Malassezia species and Hortaea werneckii. It describes the clinical manifestations of pityriasis versicolor, seborrhoeic dermatitis, tinea nigra and laboratory diagnosis. Pityriasis versicolor presents as scaly lesions that fluoresce under UV light. Seborrhoeic dermatitis causes red, greasy scaling of seborrheic areas. Tinea nigra appears as brown to black palmar macules. Direct microscopy of skin scrapings can identify characteristic yeasts and hyphae while culture growth requires lipid supplementation. Topical imidazoles are usually effective treatments.
This document summarizes several types of fungal infections of the skin, including their causes, symptoms, diagnosis, and treatment. Dermatophyte infections like tinea capitis, tinea pedis, and tinea corporis typically present as ring-shaped patches with scaling and are diagnosed by microscopic examination. Candidiasis can cause oral or genital thrush and candidal skin rashes. Pityriasis versicolor is a common fungal infection that causes discolored, scaly skin patches. Treatment involves topical or oral antifungal medications.
1. Scabies and pediculosis are parasitic infestations caused by the Sarcoptes scabiei mite and human lice respectively.
2. Scabies causes intense itching and skin lesions due to an allergic reaction to the mite and its burrows. Common signs include burrows, papules, and excoriations.
3. Pediculosis involves infestation by three types of lice - head lice, body lice, and pubic lice - which feed on human blood and cause intense itching.
Exfoliative dermatitis is a condition where more than 90% of the skin surface becomes inflamed and scaly. It can be caused by underlying skin diseases like psoriasis or eczema, drug reactions, or systemic illnesses. Clinically, it presents as generalized redness and scaling of the skin with potential complications involving other organs. Making an accurate diagnosis requires considering the patient's medical history and risk factors, examining skin changes and biopsy findings, and ruling out potential etiologies through laboratory tests and imaging.
The skin is not only the largest organ of the body, but it also forms a living biological barrier with several functions.
Pyodermas are any pyogenic skin disease (has pus). Skin infections can be caused by bacteria (often Staphylococcal or Streptococcal) either invading normal skin, or affecting a compromised skin barrier
Some bacterial skin infections resolve without serious morbidity. However, skin infections can be severe and result in sepsis or death, particularly in vulnerable patient groups.
Subcutaneous mycoses are fungal infections of the skin and subcutaneous tissue caused by soil-dwelling fungi. They include diseases like chromoblastomycosis, lobomycosis, mycetoma, and phaeohyphomycosis. Laboratory diagnosis involves examining skin scrapings or biopsy specimens microscopically for fungal elements and culturing specimens to identify the causative fungus. Histopathology may show brown-pigmented sclerotic bodies, yeast-like cells, or septate hyphae depending on the specific disease. Definitive diagnosis requires correlating clinical presentation with microscopic and culture findings.
Rosacea: Inflammatory condition in DermatologyDrSaraHistology
Rosacea is a chronic skin condition that affects the face, characterized by flushing, persistent redness, small visible blood vessels, pimples or bumps, and thickened skin, especially on the nose, cheeks, chin, and forehead. It is classified into subtypes based on symptoms such as erythema, papules and pustules, and phymatous changes. Treatment aims to reduce inflammation and prevent worsening of symptoms. Left untreated, rosacea can progress and cause permanent changes to the facial structure over many years.
This document discusses bullous diseases of the skin. It describes different types of bullous diseases including autoimmune bullous diseases like pemphigus and bullous pemphigoid. Pemphigus can be superficial or deep and is caused by antibodies against desmogleins. Bullous pemphigoid typically affects elderly patients and is characterized by large tense subepidermal blisters caused by antibodies against the basement membrane. Diagnosis involves skin biopsy and detection of antibodies. Management involves topical and systemic steroids, immunosuppressants, and monitoring of clinical response and antibody titers.
Fungal corneal ulcers are caused by fungi like Candida, Fusarium, and Aspergillus. Risk factors include contact lens wear, corneal trauma, immunosuppression, and dry eye. Symptoms include eye pain, blurry vision, redness, and tearing. Diagnosis involves examining the eye for infiltrates and satellite lesions. Tests like KOH staining, cultures, and PCR can identify fungi. Treatment involves natamycin or voriconazole eye drops for 1-3 weeks, then tapering. Oral voriconazole may be used for severe cases. Pain medications and cycloplegic drops provide symptom relief. Fungal keratitis can lead to perforation, endophthalmitis, and
This document summarizes several types of fungal infections of the skin, including their causes, symptoms, diagnosis, and treatment. Dermatophyte infections like tinea capitis, tinea pedis, and tinea corporis typically present as ring-shaped patches with scaling and are diagnosed by microscopic examination. Candidiasis can cause oral or genital thrush and candidal skin rashes. Pityriasis versicolor is a common fungal infection that causes discolored, scaly skin patches. Treatment involves topical or oral antifungal medications.
1. Scabies and pediculosis are parasitic infestations caused by the Sarcoptes scabiei mite and human lice respectively.
2. Scabies causes intense itching and skin lesions due to an allergic reaction to the mite and its burrows. Common signs include burrows, papules, and excoriations.
3. Pediculosis involves infestation by three types of lice - head lice, body lice, and pubic lice - which feed on human blood and cause intense itching.
Exfoliative dermatitis is a condition where more than 90% of the skin surface becomes inflamed and scaly. It can be caused by underlying skin diseases like psoriasis or eczema, drug reactions, or systemic illnesses. Clinically, it presents as generalized redness and scaling of the skin with potential complications involving other organs. Making an accurate diagnosis requires considering the patient's medical history and risk factors, examining skin changes and biopsy findings, and ruling out potential etiologies through laboratory tests and imaging.
The skin is not only the largest organ of the body, but it also forms a living biological barrier with several functions.
Pyodermas are any pyogenic skin disease (has pus). Skin infections can be caused by bacteria (often Staphylococcal or Streptococcal) either invading normal skin, or affecting a compromised skin barrier
Some bacterial skin infections resolve without serious morbidity. However, skin infections can be severe and result in sepsis or death, particularly in vulnerable patient groups.
Subcutaneous mycoses are fungal infections of the skin and subcutaneous tissue caused by soil-dwelling fungi. They include diseases like chromoblastomycosis, lobomycosis, mycetoma, and phaeohyphomycosis. Laboratory diagnosis involves examining skin scrapings or biopsy specimens microscopically for fungal elements and culturing specimens to identify the causative fungus. Histopathology may show brown-pigmented sclerotic bodies, yeast-like cells, or septate hyphae depending on the specific disease. Definitive diagnosis requires correlating clinical presentation with microscopic and culture findings.
Rosacea: Inflammatory condition in DermatologyDrSaraHistology
Rosacea is a chronic skin condition that affects the face, characterized by flushing, persistent redness, small visible blood vessels, pimples or bumps, and thickened skin, especially on the nose, cheeks, chin, and forehead. It is classified into subtypes based on symptoms such as erythema, papules and pustules, and phymatous changes. Treatment aims to reduce inflammation and prevent worsening of symptoms. Left untreated, rosacea can progress and cause permanent changes to the facial structure over many years.
This document discusses bullous diseases of the skin. It describes different types of bullous diseases including autoimmune bullous diseases like pemphigus and bullous pemphigoid. Pemphigus can be superficial or deep and is caused by antibodies against desmogleins. Bullous pemphigoid typically affects elderly patients and is characterized by large tense subepidermal blisters caused by antibodies against the basement membrane. Diagnosis involves skin biopsy and detection of antibodies. Management involves topical and systemic steroids, immunosuppressants, and monitoring of clinical response and antibody titers.
Fungal corneal ulcers are caused by fungi like Candida, Fusarium, and Aspergillus. Risk factors include contact lens wear, corneal trauma, immunosuppression, and dry eye. Symptoms include eye pain, blurry vision, redness, and tearing. Diagnosis involves examining the eye for infiltrates and satellite lesions. Tests like KOH staining, cultures, and PCR can identify fungi. Treatment involves natamycin or voriconazole eye drops for 1-3 weeks, then tapering. Oral voriconazole may be used for severe cases. Pain medications and cycloplegic drops provide symptom relief. Fungal keratitis can lead to perforation, endophthalmitis, and
1. Oral candidiasis is the most common fungal infection of the oral cavity, caused by Candida albicans. It presents as pseudomembranous, erythematous, or chronic hyperplastic lesions.
2. Histoplasmosis, caused by the dimorphic fungus Histoplasma capsulatum, can cause oral ulcers but is usually asymptomatic. It is endemic in certain regions of India.
3. Mucormycosis is a rare infection caused by fungi in the order Mucorales. It mainly affects immunocompromised individuals and can cause rhino-orbital or pulmonary forms. Rhino-orbital mucormycosis commonly involves the
mucoromycosis is a fungal infection mostly caused by saprophytic molds.
these fungi are found widely in environment, mostly in damp areas or areas with good carbon source, as carbon is essential or basic needs for such fungi.
their infection is categorised into three categories,
cutaneous mucoromycosis,
sub-cutaneous mucoromycosis,
disseminated mucoromycosis.
this ppt will gives you an overview regarding mucoromycosis its causative agent, parthenogenesis and lab diagnosis and treatment.
This seminar consisits of description of various bacterial diseases along with their oral manifestations,diagnosis and treatment.an addition of suitable case reports for better understanding and associated disorders
Acne vulgaris, or common acne, is a chronic inflammatory skin condition characterized by abnormalities in sebum production, follicular desquamation, bacterial proliferation and inflammation. It is the most common skin disorder, affecting over 17 million Americans. The main causes are P. acnes and S. epidermidis bacteria colonizing hair follicles and stimulating inflammation. Clinical manifestations range from non-inflammatory whiteheads and blackheads to inflammatory papules, pustules, cysts and nodules. Treatment focuses on reducing inflammation and preventing complications using topical and oral medications like benzoyl peroxide, antibiotics and retinoids. While acne usually resolves by the mid-20s, some patients
The document discusses superficial mycoses, which are fungal infections confined to the outer layer of the skin. It describes four types: pityriasis versicolor caused by Malassezia furfur presenting as discolored patches; tinea nigra caused by Exophiala werneckii appearing as brown-black palmar lesions; black piedra caused by Piedraia hortae forming hard nodules on hair; and white piedra caused by Trichosporon beigelli producing a soft white growth on hair. Diagnosis involves potassium hydroxide preparation of skin or hair samples or fungal culture. Treatment consists of topical antifungals like imidazoles or
Fungal infection of the skin, most common on the exposed surfaces of the body, namely the face, arms and shoulders.
Most common fungal diseases ; Ringworm. A common fungal skin infection that often looks like a circular rash.
лекция.pptx for std dermatovenerology, cause and symptomsneestom1998
Bullous dermatoses can be classified into several groups based on their clinical presentation and pathogenesis. This includes pemphigus, pemphigoid, herpetiform dermatitis, and others. Pemphigus is characterized by flaccid blisters caused by loss of cell adhesion within the epidermis. Pemphigoid involves subepidermal blistering. Herpetiform dermatitis presents as clusters of small vesicles on an inflamed base and is associated with gluten sensitivity. Diagnosis involves skin biopsy and immunofluorescence testing to identify the level and pattern of immune deposits. Management consists of corticosteroids, immunosuppressants, or dapsone depending on the specific condition.
This document describes several opportunistic mycoses (fungal infections) that primarily affect immunocompromised individuals. It discusses the most common fungal pathogens, including Candida, Aspergillus, Cryptococcus, Pneumocystis, Rhizopus, Mucor, and Absidia. For each pathogen, it covers topics like etiology, clinical manifestations, diagnosis, and treatment. The goal is to describe the etiology, morphology, pathogenesis and clinical spectrum of opportunistic mycoses, as well as elaborate on their laboratory diagnosis and treatment.
This document provides information on common skin conditions seen in primary care, including acne, eczema, psoriasis, benign lumps such as warts and cysts, and skin cancers. It describes the aetiology, clinical features, investigations, and management of each condition. For acne, eczema, and psoriasis, it outlines the chronic inflammatory nature, typical presentations, multi-factorial causes, and stepped treatment approaches including topical and oral medications. Benign lumps are also reviewed, including common types such as warts, cysts, and neck lumps. Finally, the document discusses skin cancers like melanoma, basal cell carcinoma, and squamous cell carcinoma, noting risk factors
1. Fungal infections of the skin, hair and nails are caused by dermatophyte fungi of three genera - Trichophyton, Microsporum, and Epidermophyton.
2. Common fungal infections include athlete's foot, nail fungus, ringworm of the groin/body, and ringworm of the scalp.
3. Symptoms vary by type of infection but often include scaling, itching, and rashes. Diagnosis involves microscopic examination of skin/nail samples and cultures.
4. Treatment involves topical antifungal creams/ointments for minor infections and oral antifungals like terbinafine, itraconazole
Fungal corneal ulcers are a significant cause of blindness worldwide, accounting for 36% of corneal ulcers in Bangladesh. Risk factors include agricultural work involving vegetable matter and trauma, as well as conditions like diabetes. Diagnosis involves corneal scraping and staining to identify fungal elements microscopically. Common fungi include Fusarium, Aspergillus, and Candida. Treatment involves natamycin or amphotericin B eye drops, sometimes with systemic antifungals. Surgery may be needed for severe cases. Prognosis depends on size, depth and organism involved.
Oral lichen planus is a chronic inflammatory disease that affects the oral mucosa. It is characterized by white striations (Wickham's striae) and varies in appearance from reticular to erythematous or ulcerative lesions. The cause is unknown but involves a cell-mediated immune response. Treatment focuses on reducing symptoms and includes topical corticosteroids, immunosuppressants, or retinoids. Malignant transformation may rarely occur so follow-up is important.
Mucormycosis is a rare but aggressive fungal infection caused by fungi of the class Zygomycetes, including Rhizopus, Mucor, and Absidia. It mainly affects immunocompromised patients or those with uncontrolled diabetes. The fungi thrive in high glucose, acidic conditions. Common forms include rhinocerebral affecting the sinuses and orbit, pulmonary, gastrointestinal, cutaneous from skin injuries, and disseminated infection of multiple organs. Diagnosis involves tissue biopsy and culture. Treatment requires intravenous amphotericin B antifungal therapy and surgical debridement of infected tissues.
Overview of Skin infections- July 2022.pdfAdamu Mohammad
This document provides an overview of various skin infections. It discusses bacterial infections like cellulitis, erysipelas, folliculitis, impetigo and furunculosis. It also covers fungal infections such as tinea, candidiasis, pityriasis versicolor and deeper fungal infections. Viral infections including warts and herpes are mentioned. Finally, it summarizes parasitic infestations like scabies, larva migrans and head lice. For each condition, it provides details on pathogenesis, clinical features, diagnosis and treatment.
This document provides information on common skin infections in children. It discusses bacterial infections like impetigo, cellulitis, folliculitis, and staphylococcal scalded skin syndrome. It also covers fungal infections, viral infections, and parasitic infections. For accurate diagnosis, a thorough history and physical exam are important. Skin lesions should be classified based on characteristics like size, color, and morphology. Proper treatment depends on the specific infection and may involve topical antibiotics, oral antibiotics, or both.
Superficial mycoses are fungal infections that affect the epidermal layer of the skin. Common causative agents include Malassezia furfur, Exophiala werneckii, Trichosporon beigelii, and Piedraia hortae. Dermatophytes are fungi that can infect the skin, hair, and nails by invading keratinized tissues. They include genera such as Microsporum, Trichophyton, and Epidermophyton. Common dermatophyte infections are tinea capitis, tinea barbae, tinea corporis, tinea cruris, tinea pedis, and tinea unguium. Laboratory diagnosis involves microscopic
This document discusses various bacterial infections that can affect the skin, including Staphylococcus aureus, Streptococcus pyogenes, Corynebacterium, and Actinomyces. It provides details on specific cutaneous infections such as impetigo, ecthyma, folliculitis, furuncles, carbuncles, erysipelas, bacterial scalded skin syndrome, and actinomycosis. It describes the causative bacteria, clinical presentation, diagnosis and treatment of these important skin infections.
This document provides an overview of various skin diseases and disorders, including:
- Psoriasis, characterized by chronic pink or red lesions with silvery scaling. Genetic and autoimmune factors may play a role. Symptoms include thick flaky scaling and pruritus.
- Acne vulgaris, an inflammatory disease of hair follicles causing comedos, papules and pustules. Hormonal changes and stress can precipitate outbreaks. Treatment focuses on reducing bacterial infection and inflammation.
- Rosacea, a chronic inflammatory condition causing erythema and pustule formation on the face. Symptoms include flushing of the cheeks, forehead and chin. Treatment includes topical cre
This document discusses mycology, which is the study of fungi. It describes the key characteristics of fungi and how they differ from bacteria. Some of the major types of fungi are yeasts, molds, and dimorphic fungi, which can exist in both yeast and mold forms. Fungal diseases are classified as superficial mycoses, mucocutaneous mycoses, subcutaneous mycoses, and deep mycoses. Common fungal infections in humans include candidiasis, dermatophytosis, and various respiratory fungal infections.
This document discusses various conditions that can affect the external nose, including infections, tumors, vascular lesions, and dermatological diseases. It provides detailed descriptions of common acute infections like furunculosis, vestibulitis, erysipelas, and cellulitis. It also covers chronic infections such as lupus vulgaris and syphilis. Benign and malignant tumors of the nose are listed. Vascular lesions including hemangiomas and pyogenic granulomas are described. Finally, it discusses dermoid cysts and their potential intracranial extensions.
Paracoccidioidomycosis is a fungal infection caused by Paracoccidioides species. It primarily involves the lungs and can disseminate to other organs. The disease ranges from asymptomatic to acute or chronic forms. Diagnosis involves microscopic examination of clinical samples to identify the characteristic yeast forms and culture growth at 37°C. Treatment requires long-term antifungal therapy for 6-12 months.
This document introduces permutation methods for statistical testing. It begins with background on permutation principles and explains that most biostatistics texts only cover rank-based permutation methods but this text will cover both rank-based and non-rank-based methods. It then reviews key mathematical concepts of permutations and combinations that are important for understanding permutation methods. It provides examples of calculating permutations and combinations. Finally, it states that several permutation-based tests will be presented, with the first using original observations and the second using ranks to test different statistical concepts like correlation in a distribution-free manner.
1. Oral candidiasis is the most common fungal infection of the oral cavity, caused by Candida albicans. It presents as pseudomembranous, erythematous, or chronic hyperplastic lesions.
2. Histoplasmosis, caused by the dimorphic fungus Histoplasma capsulatum, can cause oral ulcers but is usually asymptomatic. It is endemic in certain regions of India.
3. Mucormycosis is a rare infection caused by fungi in the order Mucorales. It mainly affects immunocompromised individuals and can cause rhino-orbital or pulmonary forms. Rhino-orbital mucormycosis commonly involves the
mucoromycosis is a fungal infection mostly caused by saprophytic molds.
these fungi are found widely in environment, mostly in damp areas or areas with good carbon source, as carbon is essential or basic needs for such fungi.
their infection is categorised into three categories,
cutaneous mucoromycosis,
sub-cutaneous mucoromycosis,
disseminated mucoromycosis.
this ppt will gives you an overview regarding mucoromycosis its causative agent, parthenogenesis and lab diagnosis and treatment.
This seminar consisits of description of various bacterial diseases along with their oral manifestations,diagnosis and treatment.an addition of suitable case reports for better understanding and associated disorders
Acne vulgaris, or common acne, is a chronic inflammatory skin condition characterized by abnormalities in sebum production, follicular desquamation, bacterial proliferation and inflammation. It is the most common skin disorder, affecting over 17 million Americans. The main causes are P. acnes and S. epidermidis bacteria colonizing hair follicles and stimulating inflammation. Clinical manifestations range from non-inflammatory whiteheads and blackheads to inflammatory papules, pustules, cysts and nodules. Treatment focuses on reducing inflammation and preventing complications using topical and oral medications like benzoyl peroxide, antibiotics and retinoids. While acne usually resolves by the mid-20s, some patients
The document discusses superficial mycoses, which are fungal infections confined to the outer layer of the skin. It describes four types: pityriasis versicolor caused by Malassezia furfur presenting as discolored patches; tinea nigra caused by Exophiala werneckii appearing as brown-black palmar lesions; black piedra caused by Piedraia hortae forming hard nodules on hair; and white piedra caused by Trichosporon beigelli producing a soft white growth on hair. Diagnosis involves potassium hydroxide preparation of skin or hair samples or fungal culture. Treatment consists of topical antifungals like imidazoles or
Fungal infection of the skin, most common on the exposed surfaces of the body, namely the face, arms and shoulders.
Most common fungal diseases ; Ringworm. A common fungal skin infection that often looks like a circular rash.
лекция.pptx for std dermatovenerology, cause and symptomsneestom1998
Bullous dermatoses can be classified into several groups based on their clinical presentation and pathogenesis. This includes pemphigus, pemphigoid, herpetiform dermatitis, and others. Pemphigus is characterized by flaccid blisters caused by loss of cell adhesion within the epidermis. Pemphigoid involves subepidermal blistering. Herpetiform dermatitis presents as clusters of small vesicles on an inflamed base and is associated with gluten sensitivity. Diagnosis involves skin biopsy and immunofluorescence testing to identify the level and pattern of immune deposits. Management consists of corticosteroids, immunosuppressants, or dapsone depending on the specific condition.
This document describes several opportunistic mycoses (fungal infections) that primarily affect immunocompromised individuals. It discusses the most common fungal pathogens, including Candida, Aspergillus, Cryptococcus, Pneumocystis, Rhizopus, Mucor, and Absidia. For each pathogen, it covers topics like etiology, clinical manifestations, diagnosis, and treatment. The goal is to describe the etiology, morphology, pathogenesis and clinical spectrum of opportunistic mycoses, as well as elaborate on their laboratory diagnosis and treatment.
This document provides information on common skin conditions seen in primary care, including acne, eczema, psoriasis, benign lumps such as warts and cysts, and skin cancers. It describes the aetiology, clinical features, investigations, and management of each condition. For acne, eczema, and psoriasis, it outlines the chronic inflammatory nature, typical presentations, multi-factorial causes, and stepped treatment approaches including topical and oral medications. Benign lumps are also reviewed, including common types such as warts, cysts, and neck lumps. Finally, the document discusses skin cancers like melanoma, basal cell carcinoma, and squamous cell carcinoma, noting risk factors
1. Fungal infections of the skin, hair and nails are caused by dermatophyte fungi of three genera - Trichophyton, Microsporum, and Epidermophyton.
2. Common fungal infections include athlete's foot, nail fungus, ringworm of the groin/body, and ringworm of the scalp.
3. Symptoms vary by type of infection but often include scaling, itching, and rashes. Diagnosis involves microscopic examination of skin/nail samples and cultures.
4. Treatment involves topical antifungal creams/ointments for minor infections and oral antifungals like terbinafine, itraconazole
Fungal corneal ulcers are a significant cause of blindness worldwide, accounting for 36% of corneal ulcers in Bangladesh. Risk factors include agricultural work involving vegetable matter and trauma, as well as conditions like diabetes. Diagnosis involves corneal scraping and staining to identify fungal elements microscopically. Common fungi include Fusarium, Aspergillus, and Candida. Treatment involves natamycin or amphotericin B eye drops, sometimes with systemic antifungals. Surgery may be needed for severe cases. Prognosis depends on size, depth and organism involved.
Oral lichen planus is a chronic inflammatory disease that affects the oral mucosa. It is characterized by white striations (Wickham's striae) and varies in appearance from reticular to erythematous or ulcerative lesions. The cause is unknown but involves a cell-mediated immune response. Treatment focuses on reducing symptoms and includes topical corticosteroids, immunosuppressants, or retinoids. Malignant transformation may rarely occur so follow-up is important.
Mucormycosis is a rare but aggressive fungal infection caused by fungi of the class Zygomycetes, including Rhizopus, Mucor, and Absidia. It mainly affects immunocompromised patients or those with uncontrolled diabetes. The fungi thrive in high glucose, acidic conditions. Common forms include rhinocerebral affecting the sinuses and orbit, pulmonary, gastrointestinal, cutaneous from skin injuries, and disseminated infection of multiple organs. Diagnosis involves tissue biopsy and culture. Treatment requires intravenous amphotericin B antifungal therapy and surgical debridement of infected tissues.
Overview of Skin infections- July 2022.pdfAdamu Mohammad
This document provides an overview of various skin infections. It discusses bacterial infections like cellulitis, erysipelas, folliculitis, impetigo and furunculosis. It also covers fungal infections such as tinea, candidiasis, pityriasis versicolor and deeper fungal infections. Viral infections including warts and herpes are mentioned. Finally, it summarizes parasitic infestations like scabies, larva migrans and head lice. For each condition, it provides details on pathogenesis, clinical features, diagnosis and treatment.
This document provides information on common skin infections in children. It discusses bacterial infections like impetigo, cellulitis, folliculitis, and staphylococcal scalded skin syndrome. It also covers fungal infections, viral infections, and parasitic infections. For accurate diagnosis, a thorough history and physical exam are important. Skin lesions should be classified based on characteristics like size, color, and morphology. Proper treatment depends on the specific infection and may involve topical antibiotics, oral antibiotics, or both.
Superficial mycoses are fungal infections that affect the epidermal layer of the skin. Common causative agents include Malassezia furfur, Exophiala werneckii, Trichosporon beigelii, and Piedraia hortae. Dermatophytes are fungi that can infect the skin, hair, and nails by invading keratinized tissues. They include genera such as Microsporum, Trichophyton, and Epidermophyton. Common dermatophyte infections are tinea capitis, tinea barbae, tinea corporis, tinea cruris, tinea pedis, and tinea unguium. Laboratory diagnosis involves microscopic
This document discusses various bacterial infections that can affect the skin, including Staphylococcus aureus, Streptococcus pyogenes, Corynebacterium, and Actinomyces. It provides details on specific cutaneous infections such as impetigo, ecthyma, folliculitis, furuncles, carbuncles, erysipelas, bacterial scalded skin syndrome, and actinomycosis. It describes the causative bacteria, clinical presentation, diagnosis and treatment of these important skin infections.
This document provides an overview of various skin diseases and disorders, including:
- Psoriasis, characterized by chronic pink or red lesions with silvery scaling. Genetic and autoimmune factors may play a role. Symptoms include thick flaky scaling and pruritus.
- Acne vulgaris, an inflammatory disease of hair follicles causing comedos, papules and pustules. Hormonal changes and stress can precipitate outbreaks. Treatment focuses on reducing bacterial infection and inflammation.
- Rosacea, a chronic inflammatory condition causing erythema and pustule formation on the face. Symptoms include flushing of the cheeks, forehead and chin. Treatment includes topical cre
This document discusses mycology, which is the study of fungi. It describes the key characteristics of fungi and how they differ from bacteria. Some of the major types of fungi are yeasts, molds, and dimorphic fungi, which can exist in both yeast and mold forms. Fungal diseases are classified as superficial mycoses, mucocutaneous mycoses, subcutaneous mycoses, and deep mycoses. Common fungal infections in humans include candidiasis, dermatophytosis, and various respiratory fungal infections.
This document discusses various conditions that can affect the external nose, including infections, tumors, vascular lesions, and dermatological diseases. It provides detailed descriptions of common acute infections like furunculosis, vestibulitis, erysipelas, and cellulitis. It also covers chronic infections such as lupus vulgaris and syphilis. Benign and malignant tumors of the nose are listed. Vascular lesions including hemangiomas and pyogenic granulomas are described. Finally, it discusses dermoid cysts and their potential intracranial extensions.
Paracoccidioidomycosis is a fungal infection caused by Paracoccidioides species. It primarily involves the lungs and can disseminate to other organs. The disease ranges from asymptomatic to acute or chronic forms. Diagnosis involves microscopic examination of clinical samples to identify the characteristic yeast forms and culture growth at 37°C. Treatment requires long-term antifungal therapy for 6-12 months.
This document introduces permutation methods for statistical testing. It begins with background on permutation principles and explains that most biostatistics texts only cover rank-based permutation methods but this text will cover both rank-based and non-rank-based methods. It then reviews key mathematical concepts of permutations and combinations that are important for understanding permutation methods. It provides examples of calculating permutations and combinations. Finally, it states that several permutation-based tests will be presented, with the first using original observations and the second using ranks to test different statistical concepts like correlation in a distribution-free manner.
Lecture-8 (Demographic Studies and Health Services Statistics).ppthabtamu biazin
This document provides an overview of key concepts in demography and health services statistics. It discusses the study of demography, including the static and dynamic aspects of populations. It also describes sources of demographic data like censuses, vital registration, and surveys. Other topics covered include demographic transition, population pyramids, vital rates like fertility and mortality rates, and population projections methods.
The chi-square test is a non-parametric method used to analyze categorical data to evaluate hypotheses about populations. It can be used for goodness of fit, independence, and homogeneity. The chi-square test involves calculating expected frequencies, verifying assumptions, selecting a significance level, computing the chi-square statistic and comparing it to a critical value to determine whether to reject or fail to reject the null hypothesis.
The document discusses t-tests and one-way ANOVA statistical tests. It provides details on how to conduct one-sample t-tests, paired t-tests, two independent sample t-tests, and one-way ANOVA. It includes the assumptions, test statistics, and procedures for each test. An example is also provided to demonstrate a one-way ANOVA comparing red blood cell folate levels between three patient groups receiving different nitrous oxide treatments.
The document provides an overview of survival analysis. It defines survival analysis as a branch of statistics that focuses on time-to-event data and their analysis. It discusses censored and truncated data, the life table method, the Kaplan-Meier estimator for estimating survival functions when there is censoring, and the Cox regression model for assessing relationships between covariates and survival times. The key aspects of survival analysis are estimating the probability of surviving past a certain time point and comparing survival distributions between groups while accounting for censored observations.
This document provides an overview of logistic regression. It begins by explaining that linear regression is not appropriate when the dependent variable is dichotomous. Logistic regression uses an S-shaped logistic function to model the probabilities of different outcomes. The logistic function transforms the non-linear probabilities into linear-looking data that can be modeled using linear regression. Examples are provided to demonstrate how logistic regression can be used to predict the probability of coronary heart disease based on age and to analyze the relationship between patient satisfaction and residence.
Linear regression was used to analyze the relationship between daily food intake (independent variable) and weight gain (dependent variable) in a sample of 20 children. The regression equation obtained was: Weight gained = 0.16 + 0.643(food weight). This indicates that for each additional 1kg of daily food intake, a child's weight increases by 0.643kg on average. The coefficient of determination (R2) was 0.81, meaning 81% of the variation in children's weight gain was explained by differences in daily food intake.
Lecture-3 Probability and probability distribution.ppthabtamu biazin
This document provides an overview of key concepts in probability and probability distributions that will be covered in the chapter. The objectives are to understand probability, the difference between probability and probability distributions, conditional probability, and different types of distributions for categorical and continuous variables. Specific distributions discussed include the normal, student t, and chi-square distributions. Examples are provided on probability, conditional probability, counting rules for permutations and combinations, sampling with and without replacement, and the binomial distribution.
1) The document discusses descriptive statistics and methods for summarizing categorical and numerical data through tables, graphs, and numerical measures.
2) Descriptive statistics are used to describe and characterize data through methods like frequency tables, measures of central tendency, and measures of variability.
3) Various graphs like bar charts, pie charts, histograms and frequency polygons are demonstrated to visually depict distributions of categorical and numerical variables.
Fungi constitute an important group of eukaryotic organisms including yeasts and molds. Anti-fungal drugs target differences between fungal and human cells, such as fungal cell walls and sterol composition. Major classes of anti-fungals include polyenes such as amphotericin B, azoles, and allylamines. Amphotericin B binds to ergosterol in fungal cell membranes, forming pores that disrupt membrane function. It has broad antifungal activity but can cause renal toxicity. Newer lipid formulations reduce this toxicity. Nystatin is a polyene used topically due to toxicity concerns. Griseofulvin and flucytosine inhibit fung
The document discusses opportunistic fungal infections, focusing on Aspergillosis, Candidiasis, Cryptococcosis, and other mycoses. It provides details on:
- The causative fungi and their incidence in opportunistic infections
- Clinical manifestations of various fungal infections in different organ systems like the lungs and central nervous system
- Laboratory methods for diagnosing fungal infections through microscopy, culture, serology and molecular identification
- Specific details on presentations of Aspergillosis, Candidiasis and Cryptococcosis in the lungs, skin and brain
The document discusses immunology and immunopathology of human parasitic infections. It covers:
1) Microparasites multiply within host cells and pose an immediate threat, while macroparasites (helminths) do not multiply within the host and do not present an immediate threat.
2) Infections by protozoa and helminths are long-lasting and can induce immunopathological changes over years that are more dangerous than the initial infection.
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Philippine Edukasyong Pantahanan at Pangkabuhayan (EPP) CurriculumMJDuyan
(𝐓𝐋𝐄 𝟏𝟎𝟎) (𝐋𝐞𝐬𝐬𝐨𝐧 𝟏)-𝐏𝐫𝐞𝐥𝐢𝐦𝐬
𝐃𝐢𝐬𝐜𝐮𝐬𝐬 𝐭𝐡𝐞 𝐄𝐏𝐏 𝐂𝐮𝐫𝐫𝐢𝐜𝐮𝐥𝐮𝐦 𝐢𝐧 𝐭𝐡𝐞 𝐏𝐡𝐢𝐥𝐢𝐩𝐩𝐢𝐧𝐞𝐬:
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2. Superficial Mycoses
• These are superficial cosmetic fungal infections of the skin or hair shaft.
• No living tissue is invaded
• There is no cellular response from the host.
• Essentially no pathological changes are elicited.
• These infections are often so innocuous that patients are often unaware of their
condition.
4/1/2023 2
3. Superficial Mycoses…
Disease Causative organisms Incidence
Pityriasis versicolor
Seborrhoeic dermatitis
including Dandruff and
Follicular pityriasis
Malassezia spp.
(a lipophilic yeast)
Common
Tinea nigra Hortaea werneckii Rare
White piedra Trichosporon spp. Common
Black piedra Piedraia hortae Rare
4/1/2023 3
4. 1. Malassezia infection
• Malassezia species are basidiomycetous yeasts
• Part of the normal skin flora of humans and animals
• The genus now includes 14 species of which 13 are lipid dependent.
• These include:
4/1/2023 4
5. Malassezia infection …
Malassezia species Host
M. caprae Goat, horse
M. dermatis Human
M. equina horse, cow
M. furfur Human , cow, elephant, pig, monkey, ostrich, pelican
M. globosa Human , cheetah, cow
M. japonica Human
M. nana cat, cow, dog
M. obtusa Human
M. pachydermatis dog, cat, carnivores, birds
M. restricta Human
M. slooffiae Human , pig, goat, sheep
M. sympodialis Human, horse, pig sheep
M. yamatoensis Human
(Cabanes et al. 2011)
4/1/2023 5
6. Malassezia infection…
• M. sympodialis, M. globosa, M. slooffiae and M. restricta are the most frequently
found species responsible for colonization of humans (Arendrup et al. 2014).
• Malassezia species may cause various skin manifestations including pityriasis
versicolor, seborrhoeic dermatitis, dandruff, atopic eczema and folliculitis.
• M. pachydermatis is known to cause external otitis in dogs.
• Fungaemia due to lipid-dependent Malassezia species usually occurs in patients
with central line catheters receiving lipid replacement therapy, especially in infants
4/1/2023 6
7. Clinical manifestations
• Pityriasis versicolor:
• This is a chronic, superficial fungal disease of the skin characterized by well-demarcated
white, pink, fawn, or brownish lesions, often coalescing, and covered with thin furfuraceous
scales.
• The colour varies according to the normal pigmentation of the patient, exposure of the area to
sunlight, and the severity of the disease.
• Lesions occur on the trunk, shoulders and arms, rarely on the neck and face, and fluoresce a
pale greenish colour under Wood's ultra-violet light.
• Young adults are affected most often, but the disease may occur in childhood and old age.
4/1/2023 7
9. Clinical manifestations…
• Pityriasis folliculitis:
• This is characterized by follicular papules and pustules localized to the back, chest and upper
arms, sometimes the neck, and more seldom the face.
• These are itchy and often appear after sun exposure.
• Scrapings or biopsy specimens show numerous yeasts occluding the mouths of the infected
follicules.
• Most cases respond well to topical imidazole treatment, however patients with extensive
lesions often require oral treatment with ketoconazole or itraconazole.
• Once again, prophylactic treatment once or twice a week is mandatory to prevent relapse.
4/1/2023 9
11. Clinical manifestations…
• Seborrhoeic dermatitis and dandruff:
• Current evidence suggests Malassezia, combined with multifactorial host factors is also the
direct cause of seborrhoeic dermatitis, with dandruff being the mildest manifestation.
• Host factors include genetic predisposition, an emotional component (possible endocrine or
neurologically mediated factors), changes in quantity and composition of sebum (increase in
wax esters and a shift from triglycerides to shorter fatty acid chains), increase in alkalinity of
skin (due to eccrine sweating) and external local factors such as occlusion.
• Patients with neurological diseases such as Parkinson's disease and those with AIDS are
commonly affected.
4/1/2023 11
12. Clinical manifestations…
• Seborrhoeic dermatitis and dandruff:
• Clinical manifestations are characterized by erythema and scaling in areas with a rich supply
of sebaceous glands i.e. the scalp, face, eyebrows, ears and upper trunk.
• Lesions are red and covered with greasy scales and itching is common in the scalp.
• The clinical features are typical and skin scrapings for a laboratory diagnosis are unnecessary.
• Once again, the use of a topical imidazole is recommended, especially ketoconazole which has
proved to be the most effective agent.
• Relapse is common and retreatment when necessary is the simplest approach for long term
management.
4/1/2023 12
13. Clinical manifestations…
• Fungaemia:
• Malassezia has also been reported as causing catheter acquired fungaemia in
neonate and adult patients undergoing lipid replacement therapy.
• Such patients may also develop small embolic lesions in the lungs or other
organs.
• Diagnosis requires special culture media and blood drawn back through the
catheter is the preferred specimen.
• Culture of the catheter tip is also recommended.
4/1/2023 13
14. Laboratory diagnosis:
• Clinical material:
• Skin scrapings from patients with superficial lesions, blood and indwelling catheter tips from
patients with suspected fungaemia.
• Direct microscopy:
• Skin scrapings taken from patients with Pityriasis versicolor stain rapidly when mounted in
10% KOH, glycerol and Parker ink solution and
• show characteristic clusters of thick-walled round, budding yeast-like cells and short angular
hyphal forms up to 8um in diameter (ave. 4um diam.).
• These microscopic features are diagnostic for Malassezia furfur and culture preparations are
usually not necessary.
4/1/2023 14
15. Laboratory diagnosis:
GMS stained skin biopsy showing characteristic spherical yeast
cells and short pseudohyphal elements typical of M. furfur; and
4/1/2023 15
10% KOH with Parker ink mount showing characteristic
spherical yeast cells and short pseudohyphal elements typical
of the fungus.
16. Laboratory diagnosis…
• Culture:
• Culture is only necessary in cases of suspected fungaemia.
• M. furfur is a lipophilic yeast, therefore in vitro growth must be stimulated by
natural oils or other fatty substances.
• The most common method used is to overlay Sabouraud's dextrose agar
containing cycloheximide (actidione) with olive oil or
• alternatively to use a more specialized media like Dixon's agar which contains
glycerol mono-oleate (a suitable substrate for growth).
4/1/2023 16
17. Laboratory diagnosis:
Culture of M. furfur on Dixon's agar.
Identification:
• Microscopic evidence of unipolar,
broad base budding yeast cells and
special lipid requirements for growth
in culture are usually diagnostic.
4/1/2023 17
18. Laboratory diagnosis…
• Serology:
• There are currently no commercially available serological procedures for the
diagnosis of Malassezia infections.
4/1/2023 18
19. Management:
• The most appropriate antifungal treatment for pityriasis versicolor is to use a topical imidazole in a
solution or lathering preparation.
• Ketoconazole shampoo has proven to be very effective.
• Alternative treatments include zinc pyrithione shampoo or selenium sulfide lotion applied daily for
10-14 days or the use of propylene glycol 50% in water twice daily for 14 days.
• In severe cases with extensive lesions, or in cases with lesions resistant to topical treatment or in
cases of frequent relapse oral therapy with itraconazole [200 mg/day for 5-7 days] is usually
effective.
4/1/2023 19
20. Management…
• Mycologically, yeast cells may still be seen in skin scrapings for up to 30 days following treatment,
thus patients should be monitored on clinical grounds.
• Patients also need to be warned that it may take many months for their skin pigmentation to return
to normal, even after the infection has been successfully treated.
• Relapse is a regular occurrence and prophylactic treatment with a topical agent once or twice a
week is often necessary to avoid recurrence
4/1/2023 20
21. 2. Tinea nigra
• A superficial fungal infection of skin
• Characterized by brown to black macules which usually occur on the palmar aspects of
hands and occasionally the plantar and other surfaces of the skin.
• World-wide distribution
• More common in tropical regions of Central and South America, Africa, South-East Asia
and Australia.
• The etiological agent is Hortaea werneckii a common saprophytic fungus believed to
occur in soil, compost, humus and on wood in humid tropical and sub-tropical regions.
4/1/2023 21
22. Tinea nigra…
• Clinical manifestations:
• Skin lesions are characterized by brown to black macules which usually occur on the
palmar aspects of hands and occasionally the plantar and other surfaces of the skin.
• Lesions are non-inflammatory and non-scaling.
• Familial spread of infection has also been reported
• There is no inflammatory reaction
4/1/2023 22
23. Tinea nigra
Typical brown to black, non-scaling macules on the palmar aspect of the
hands. Note: there is no inflammatory reaction.
4/1/2023 23
24. Laboratory diagnosis
Clinical material: Skin scrapings
• Direct microscopy: Skin scrapings should be examined using 10% KOH and
Parker ink or calcofluor white mounts.
Skin scrapings mounted in 10% KOH showing pigmented brown to dark olivaceous (dematiaceous) septate hyphal
elements and 2-celled yeast cells producing annelloconidia typical of Hortaea werneckii.
4/1/2023 24
25. Laboratory diagnosis…
• Culture:
• Clinical specimens should be inoculated onto primary isolation media, like SDA.
• Identification: Characteristic clinical, microscopic and culture features.
• Causative agents: Hortaea werneckii
Colony and conidia of Hortaea werneckii
4/1/2023 25
26. Laboratory diagnosis:
• Serology: Not required for diagnosis
• Management:
• Usually, topical treatment with Whitfield's ointment (benzoic acid compound) or
• an imidazole agent twice a day for 3-4 weeks is effective
4/1/2023 26
27. 3. White piedra
• White piedra is a superficial cosmetic fungal infection of the hair shaft caused by Trichosporon spp.
• Infected hairs develop soft greyish-white nodules along the shaft.
• Essentially no pathological changes are elicited.
• White piedra is found worldwide, but is most common in tropical or subtropical regions.
• Trichosporon species are a minor component of normal skin flora, and are widely distributed in
nature.
• They are regularly associated with the soft nodules of white piedra, and
• Have been involved in a variety of opportunistic infections in the immunosuppressed patient
4/1/2023 27
28. White piedra …
• Disseminated infections are
• most frequently (75%) caused by T. asahii
• have been associated with leukaemia, organ transplantation, multiple myeloma, aplastic
anaemia, lymphoma, solid tumours and AIDS
• are often fulminate and widespread
• lesions occurring in the liver, spleen, lungs and gastrointestinal tract
• Infections in non-immunosuppressed patients include
Endophthalmitis after surgical extraction of cataracts,
Endocarditis usually following insertion of prosthetic cardiac valves,
Peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPD), and
Intravenous drug abuse
4/1/2023 28
29. White piedra …
• Clinical manifestations:
• Infections are usually localized to the axilla or scalp
• May also be seen on facial hairs and sometimes pubic hair.
• White piedra is common in young adults.
• White Piedra is characterized by
• The presence of irregular, soft, white or light brown nodules, 1.0-1.5 mm
in length, firmly adhering to the hairs.
4/1/2023 29
30. White piedra …
White piedra showing soft, light brown nodules, adhering to the hairs.
4/1/2023 30
31. Laboratory diagnosis:
Clinical material:
• Epilated hairs with white soft nodules present on the shaft.
• Direct microscopy:
• Hairs should be examined using 10% KOH and Parker ink or calcofluor white
mounts.
• Look for irregular, soft, white or light brown nodules, 1.0-1.5 mm in length,
firmly adhering to the hairs.
4/1/2023 31
32. Laboratory diagnosis…
KOH and Parker ink mount of a hair nodules of white piedra showing yeast-like cells of Trichosporon spp.
4/1/2023 32
33. Laboratory diagnosis…
• Culture:
• Hair fragments should be implanted onto primary isolation media, like SDA.
• Colonies of Trichosporon spp. are white or yellowish to deep cream colored, smooth,
wrinkled, velvety, dull colonies with a mycelial fringe.
• Serology: Not required for diagnosis
• Identification:
• Characteristic clinical, microscopic and culture features.
4/1/2023 33
35. Causative agents:
• The taxonomy of Trichosporon has been redefined:
• Trichosporon cutaneum, T. dermatis, T. jirovecii and T. mucoides have now been
transferred to the new genus Cutaneotrichosporon, while Trichosporon domesticum,
T. loubieri and T. mycotoxinovorans have now been included into the re-defined
genus Apiotrichum.
• Four species Trichosporon asahii, T. asteroides, T. inkin, and T. ovoides are the most
common clinical isolates, however, T. cormiiforme, T. dohaense ,T. faecale, T.
japonicum and T. lactis have also been reported from human and animal infections
• Importantly, all species are resistant to echinocandins
4/1/2023 35
36. Management:
• Shaving the hairs is the simplest method of treatment.
• Topical application of an imidazole agent may be used to prevent reinfection.
4/1/2023 36
37. 4. Black piedra
• Black piedra is a superficial fungal infection of the hair shaft caused by Piedra
hortae.
• An ascomycetous fungus forming hard black nodules on the shafts of the scalp,
beard, moustache and pubic hair.
• It is common in Central and South America and South-East Asia.
4/1/2023 37
38. Clinical manifestations:
• Infections are usually localized to the scalp
• may also be seen on hairs of the beard, moustache and pubic hair.
• Mostly affects young adults and
• Epidemics in families have been reported following the sharing of combs and
hairbrushes.
• Infected hairs generally have a number of hard black nodules on the shaft.
• Black piedra may be confused with trichorrhexis nodosa and trichonodosis but
mycological examination will always confirm the diagnosis.
4/1/2023 38
39. Laboratory diagnosis
• Clinical material: Epilated hairs with hard black nodules present on the shaft.
• Direct microscopy:
• Hairs should be examined using 10% KOH and Parker ink or calcofluor white. Look for darkly pigmented nodules that may
partially or completely surround the hair shaft.
• Nodules are made up of a mass of pigmented with a stroma-like centre containing asci.
• Culture: Hair fragments should be implanted onto primary isolation media, like Sabouraud's dextrose agar.
Colonies of Piedra hortae are dark, brown-black and take about 2-3 weeks to appear.
• Serology: Not required for diagnosis.
• Identification: Characteristic clinical, microscopic and culture features.
• Causative agents: Piedra hortae
4/1/2023 39
40. Management:
• The usual treatment is to shave or cut the hairs short, but this is often not
considered acceptable, particularly by women.
• In-vitro susceptibility tests have shown that Piedra hortae is sensitive to
terbinafine
• it has been successfully used, at a dose of 250 mg a day for 6 weeks
4/1/2023 40
Note: With the exception of M. pachydermatis, the primary isolation and culture of Malassezia species is challenging because in vitro growth must be stimulated by natural oils or other fatty substances.
The most common method used is to overlay SDA containing cycloheximide (actidione) with olive oil or alternatively to use a more specialized media like modified Leeming and Notham agar.