More Related Content
What's hot
What's hot (20)
Viewers also liked
Viewers also liked (20)
Similar to Bacterial infections
Similar to Bacterial infections (20)
Recently uploaded
Recently uploaded (20)
Bacterial infections
- 2. • Staphylococcus Aureus • Coagulase-negative Staphylococci, • Bacillus Anthracis • Corynebacterium Diphtheriae • Anaerobic Diphtheriods (P.Acnes) • Aerobic Diphtheroids (C.Minutissimum) • Clostridium Perfringes • Borrelia Burgdorferi • Bartonella Henselae & B.Quintana Gram-positive bacteria
- 3. • Meningococcal infection • Gonococcal infection • Acinetobacter infection • Moraxella infection • Chancroid • Salmonella infection • Pseudomonas infection • Rhinoscleroma • Tularaemia • Pasteurella infection • Plague and Yersinia infections • Brucellosis • Infections due to Bartonella spp • Ehrlichiosis
- 4. Anaerobic bacteria • Tropical ulcer • Granuloma inguinale Actinomycete infections • Actinomycosis, • Nocardiosis Others • Spirochaetes and spiral bacteria • Botryomycosis • Necrotizing subcutaneous infections • Mycoplasma infections • Chlamydiae • Rickettsial infections • Dermatoses possibly attributable to bacteria
- 5. Involvement of Staphylococcus aureus in cutaneous disease Direct infection of skin and adjacent tissues • Impetigo • Ecthyma • Folliculitis • Furunculosis, • Carbuncle • Sycosis • Occasionally in cellulitis, • Others Secondary infection • Eczema, infestations, ulcers, etc. Cutaneous disease due to effect of bacterial toxin • Staphylococcal scalded skin syndrome • Toxic shock syndrome • Staphylococcal scarlatina
- 6. Involvement of streptococci (mostly group A) in cutaneous disease. Direct infections of skin or subcutaneous tissue • Impetigo • Ecthyma • Erysipelas • Cellulitis • Vulvovaginitis • Perianal infection • Streptococcal ulcers • Blistering distal dactylitis • Necrotizing fasciitis • Others Secondary infection • Eczema, infestations, ulcers, etc. Tissue damage from circulating toxin • Scarlet fever • Toxic shock-like syndrome Skin lesions attributed to allergic hypersensitivity to streptococcalantigens • Erythema nodosum • Vasculitis Skin disease provoked or influenced by streptococcal infection (mechanism uncertain) • Psoriasis, especially guttate forms
- 7. IMPETIGO • Impetigo is a contagious superficial pyogenic infection of the skin • Bullous and Nonbullous. Bullous impetigo - S. aureus. Non Bullous - S. aureus and less often by group A streptococcus, or by both organisms
- 8. • In non-bullous impetigo, the initial lesion is a very thin-walled vesicle on an erythematous base. • The vesicle ruptures rapidly into a honey- colored crusted plaque • Face, esp around nose & mouth, limbs • Constitutional symptoms & regional adenitis + • >70 percent of cases of impetigo • occurs in children of all age
- 9. • In bullous impetigo, the bullae are less rapidly ruptured and become much larger • persist for 2 or 3 days. • After rupture thin, flat, brownish crusts are formed. • Although the face is often affected, the lesions may occur anywhere • The buccal mucous membrane may be involved. • Regional adenitis is rare • 10% Pediatric diseases • can also occur in adults
- 10. • Diagnosis based on clinical appearance • Aspiration of blister fluid for gram stain and cultures • Treatment : antibiotics
- 11. STAPHYLOCOCCAL SCALDED SKIN SYNDROME • A syndrome which is a generalised exanthematous disease consisting of cutaneous tenderness and widespread superficial blistering and denudation • Common in infants / children , also in adults • Risk factors for adults : - compromised immune response , malignancy - Renal insufficiency - Alcohol abuse
- 12. • exanthem or uniform erythema sparing mucosal surfaces • cutaneous tenderness – early stage • Perioral and flexural exanthema • Purulent conjunctivitis , Otitis media , Nasopharyngeal infection or pyogenic skin infection • Large flaccid bullae , Nikolsky`s sign • Superficial tissue paper like wrinkling of Epidermis
- 13. • Toxic features • Resolves spontaneously • Healing complete – 5-7 days • C/s ( intact blister ) - sterile Treatment • Uncomplicated cases : Oral antibiotics with fluid and electrolyte management • Neonates – incubators to maintain body temperature and humidity • Use of non adherent dressings (petroleum impregnated gauze) to superficial blistering areas with mupirocin application
- 14. Toxic shock syndrome • Fever , rash followed in 1-3 weeks by desquamation , circulatory shock and mutisystem involvement mediated by one or more toxins elaborated by Staphylococcus aureus. • TSST – 1 • ENTEROTOXINS B & C - post surgical & burn wounds,sinusitis, Osteomyelitis, Influenza,IV drugGynecologic infections Rx Supportive and focused on eradicating the offending S.aureus • Antistaphyloccal antibiotics • Avoidance of tampoons , diaphragms and contraceptive sponges
- 15. ECTHYMA • Ecthyma is a pyogenic infection of the skin characterized by the formation of adherent crusts, beneath which ulceration occurs. • consequence of neglected impetigo. • S. aureus and/or grp A streptococcus can be isolated on culture • Poor hygiene and neglect are key elements in pathogenesis.
- 16. • Small bullae or pustules on an erythematous base are soon surmounted by a hard crust nof dried exudate • increases in size by peripheral accretion. • The base may become indurated and a red oedematous areola is often present. • The crust is removed -reveals a purulent irregular ulcer. • Healing occurs after a few weeks, with scarring. • The buttocks, thighs and legs are most commonly affected. Treatment. • Improved hygiene and nutrition • treatment of other underlying disease, • The antibiotic chosen should be active against both Streptococcus pyogenes and Staphylococcus
- 17. • Cellulitis is an acute, subacute or inflammation of subcutaneous tissue in which an infective, generally bacterial, cause is proven or assumed. • Most commonly: Staph • Erysipelas is a bacterial infection of the dermis and upper subcutaneous tissue; • its hallmark is a well- defined, raised edge reflecting the more superficial (dermal) involvement. • Most commonly: Strepto
- 18. Folliculitis • This is a pyoderma that begins within the hair follicle • classified according to the depth of invasion • superficial and deep,
- 19. Superficial folliculitis • Subacute or chronic folliculitis, in which the inflammatory changes are confined to the ostium or extend only slightly below it, • heals without scar formation, • Infective, physical & chemical injury • A small fragile dome-shaped pustule • Often on the scalps of children and in the beard area, axillae, extremities, and buttocks of adults.
- 21. Deep folliculitis(Sycosis barbae) • Deep folliculitis with perifollicular inflammation occurring in the bearded areas of the face and upper lip • Untreated -the lesions may become more deeply seated and chronic. • Local Rx with warm saline compresses and local antibiotics (mupirocin) sufficient to control infection. • More extensive cases require systemic antibiotic therapy.
- 22. Furuncles • Deep-seated inflammatory nodule that develops about a hair follicle • usually from a preceding superficial folliculitis and often evolving into an abscess. • hair-bearing & sites prone for friction, occlusion, and perspiration, such as the neck, face, axilla & buttocks. • complicate preexisting lesions such as atopic dermatitis, excoriations, abrasions, scabies, or pediculosis, but occur more often in the absence of any local predisposing causes
- 24. Host factors associated with furunculosis: • obesity, blood dyscrasias, defects in neutrophil function, Rx with glucocorticoids and cytotoxic agents, and immune globulin deficiency states, DM • Starts as a hard, tender, red folliculocentric nodule in hair-bearing skin that enlarges and becomes painful - Rupture occurs, with discharge of pus and often a core of necrotic material. • Solitary/multiple
- 25. • A carbuncle is a deep infection of a group of contiguous follicles with Staphylococcus aureus, accompanied by intense inflammatory changes in the surrounding and underlying connective tissues, including the subcutaneous fat. • occur predominantly in men, and usually in middle or old age • more common in the presence of diabetes, malnutrition, cardiac failure, drug addiction or severe generalized dermatoses, such as exfoliative dermatitis or pemphigus, and during prolonged • steroid therapy. Carbuncle
- 26. • The term carbuncle is derived from the Latin word for a small, fiery coal, describes the painful, hard, red lump that is the initial stage of the infection. • Suppuration begins after 5–7 days, and pus is discharged from the multiple follicular orifices. • Necrosis leaves a yellow slough surmounting a crateriform nodule. • the nape of the neck, the back, or thighs • Fever and malaise +
- 27. Erysipelas Acute inflammation of skin & subcutaneous tissue caused by streptococci Onset- abrupt Symptoms: Pain, fever chills Signs: Tense, bright red oedematous sharply demarcated smooth hot area Complications: Skin necrosis, sub cutaneous abscess, septicaemia Treatment: - Treatment of underlying factors - Local, sisomycin, fusidic acid nupirocin - Systemic Ensamycin, Cephalexin, Cefadroxil, Azithromycin
- 28. Coryneform bacteria • Erythrasma is a mild, chronic, localized superficial infection of the skin caused by Corynebacterium minutissimum. • occurs most commonly in the groins, axillae and the intergluteal and submammary flexures. • Coral-red fluorescence with Wood’s light is attributable to coproporphyrin III
- 29. • Pitted keratolysis:A superficial infection of the skin apparently caused by a species of Corynebacterium and producing circular erosions on the soles
- 30. Actinomycosis • A chronic, spreading suppurative and granulomatous disease caused primarily by Actinomyces israelii: • draining sinuses are formed through which the characteristic sulphur granules are discharged • five main clinical types depending on the primary site of infection; namely, cervicofacial (lumpy jaw), thoracic, abdominal, primary cutaneous and pelvic.
- 31. • Cultures: appear after anaerobic incubation at 37°C for 2–4 days on enriched media (brain– heart infusion glucose agar) • white, glistening, nodular colonies with somewhat irregular margins Treatment : • Penicillin • Surgical debridement