• Like
Seminar clinical approach to papulosqamous disorders.
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

Seminar clinical approach to papulosqamous disorders.

  • 1,500 views
Published

psoriasis, lichen planus, p. rosea, pityriasis lichenoides, seb. dermatitis, lichen nitidus, lichen striatus, pityriasis rubra pilaris, erythroderma, exfoliative dermatitis, secondary syphilis, …

psoriasis, lichen planus, p. rosea, pityriasis lichenoides, seb. dermatitis, lichen nitidus, lichen striatus, pityriasis rubra pilaris, erythroderma, exfoliative dermatitis, secondary syphilis, discoid lupus erythematosus, parapsoriasis

Published in Education
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
1,500
On SlideShare
0
From Embeds
0
Number of Embeds
1

Actions

Shares
Downloads
56
Comments
0
Likes
2

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Moderator: Dr Amit Malhotra
  • 2. Introduction  Group of diseases in which primary lesion is most commonly a papule,  Usually erythematous, with a variable degree of scaling on surface  Plaques form through coalescing of primary lesions  Both morphology of papule and character of scale give clues to making a diagnosis
  • 3. Papulosquamous disorders Psoriasis Lichen Planus Pityriasis rosea Parapsoriasis eg. small / large plaque pityriasis rubra pilaris Lichen nitidus Pityriasis lichenoides Lichen striatus Exfoliative dermatitis Seborrheic dermatitis
  • 4.  Other important papulosquamous diseases • • • • • • • • • • • • • Mycosis fungoides (cutaneous T-cell lymphoma) Discoid lupus erythematosus Subacute cutaneous lupus erythematosus Tinea corporis Nummular eczema Secondary syphilis Drug eruptions Erythema dyschromicum perstans Keratosis lichenoides chronica Lichen sclerosus Lichenoid dermatitis Lichenoid reaction of graft-versus-host disease Extramammary Paget’s disease
  • 5.      Common, Chronic, Disfiguring, Inflammatory & Proliferative, Genetically and environmentally influenced condition of skin and joints  Unpredictable course  Remissions & exacerbations : Epidemiology Prevalence 0.1- 3%. Bimodal age distribution. Type I – 75%, 15 - 40 Yr of age Type II ─ >40 Yr of age No gender predilection. Develop earlier in women Winter aggravation frequent.
  • 6.  Exact cause-unknown  Genetic predisposition  Precipitating factors  Immunopathogenesis  Epidermal hyperplasia  Vascular changes Genetic Background ↓↓ Provocating Factors ↓↓ Exogenous/Endogenous antigens ↓↓ Antigen presentation by APCs ↓↓ T lymphocyte- mediated Immune response ↓↓ Secretion of cytokines ↓↓ Inflammation & cellular hyperproliferation ↓↓ Clinical Lesions of psoriasis
  • 7. Causes and Pathogenesis • • • • • Genetic predisposition - 30% have first degree relative, Seen in 65% of identical twins, More frequency of HLA-B 13, HLA-B17, HLA-Cw6 is seen, 9 psoriasis susceptibility loci on different chromosomes have been identified (PSORS 1-9) Environmental trigger – • Trauma • Infection - streptococcal infection often triggers guttate and plaque psoriasis. Others are HCV, HIV, HSV, CMV • Hormonal - Psoriasis frequently improves in pregnancy and relapse postpartum. • Drugs - Antimalarials, beta-blockers, NSAIDs ACEIs and lithium may worsen psoriasis. withdrawal of systemic steroids or potent topical steroids. • Others – Sunlight, smoking and alcohol intake, Emotional upset and hypocalcemia • Obesity - Excess weight increases risk of inverse psoriasis
  • 8. Disorder of excessive growth and reproduction of skin cells Effector cytokine IL-2,IL-17,IL22,INF-γ and TNF-α leads to •Shortening of cell cycle 8 times •Proliferative cell increase 2 times •Germinative cell enter growth fraction100 % Immune-mediated disorder Both of these abnormalities can induce other, Leading to a vicious cycle of keratinocyte proliferation and inflammatory reaction, But it is still not clear which is primary defect.
  • 9. Pathology:  Hyperkeratosis and parakeratosis with focal orthokeratosis and        Munro microabscess formation Near absent granular layer. Spongiform pustules of kogoj in Malpighian layer Acanthosis Rete ridges: elongated and clubbed, branched or fused at their bases, Suprapapillary epidermal thinning Infiltrate: mononuclear leukocyte infiltrates in lower half of epidermis and in upper dermis and polymorphs in upper epidermis Dilated, tortuous papillary blood vessels
  • 10. Morphology of Chronic plaque psoriasis (psoriasis vulgaris):  Well-defined with distinct border.  Erythematous (salmon pink) papules and plaques of variable size  Covered with a silvery white, loosely adherent scales, accentuated by grating lesions  Which on removal may reveal punctate bleeding points (Auspitz sign),
  • 11.  Isomorphic (koebner)      phenomenon is positive in 38 – 76% of cases. Koebner reaction may also be found in other dermatoses like, lichen planus, lichen nitidus and vitiligo. Reverse koebner phenomenon may be seen. Itching is variable. In Resolving lesions a peripheral halo around lesion, woronoff ring may be seen. Resolved lesion may show post inflammatory hypomelanosis
  • 12. Psoriasis vulgaris: typical plaque which is welldefined, discoid, erythematous, indurated and surmounted with loose silvery scales Psoriasis vulgaris: discoid lesions become confluent to give rise to gyrate and polycyclic lesions. Grattage test and Auspitz sign: accentuation of scales by grating with a glass slide (StepA) and finally appearance of bleeding points (Step C). Woronoff’s ring: vasoconstriction around active plaques of psoriasis.
  • 13.  Distribution: B/L symmetrical       on extensors elbows, knees, shin, knuckles, sacral areas and scalp Sometimes generalized. Uniformity: plaques tend to have same features irrespective of site except on palms and soles, and flexors. Patterns seen: plaques are oval or irregular in shape, May coalesce together to form large plaques, gyrate, polycyclic and geographic plaques. Central clearing results in annular lesions. Follicular, nummular, linear, circinate pattern may be seen
  • 14. Clinical variants Guttate psoriasis  Commonly seen in Childhood and young       adults, (1.9% cases) Streptococcal throat infection usually precedes onset or flare up Mildly itchy, small, drop – like, round to oval, salmon – pink colored, papular lesions with fine scales appear in crops, Distributed more or less evenly over body, on upper trunk and proximal limbs Palms & soles are spared Resolve spontaneously or may convert to plaque form If lesions enlarged to few cms. to form coin shaped lesion k/a nummular psoriasis
  • 15. Rupioid, elephantine and ostraceous psoriasis  Plaques associated with gross hyperkeratosis.  Rupioid psoriasis - Heaped up scales, so the lesions appear conical. Scales are firmly adherent to underlying skin (limpet-like)  Elephantine psoriasis Unusual but very persistent, thickly scaling, large plaques that sometimes occur on back, limbs, hips  Ostraceous psoriasis refers to a ring-like hyperkeratotic lesion with a concave surface, resembling an oyster shell.
  • 16. Unstable psoriasis  Phases of disease in which activity is marked and course      and immediate outcome unpredictable; Previously stable and chronic form is exacerbated by inappropriate management and threatens to become erythrodermic or pustular, Localized pustular or ill-defined erythematous lesions may appear spontaneously for first time. Patients may develop such unstable phases repeatedly, Settling back again into classical forms of disease. Withdrawal of intensive systemic or topical corticosteroid therapy, hypocalcaemia, acute infection, overtreatment with tar, dithranol or UV irradiation, and severe emotional upset, may precipitate this condition.
  • 17. Erythrodermic psoriasis  Important cause of erythroderma (30%)  Can evolve from pre-existing plaque psoriasis     gradually or can occur suddenly C/f – patient may be febrile and ill, Generalized itching, intense erythema, and superficial, fine, white scaling all over body Edema, fissures, exudation and nail dystrophy may be present May lead to protein loss, hypo or hyperthermia, dehydration, electrolyte imbalance, renal failure and cardiac failure
  • 18. Pustular psoriasis  Localized pustular psoriasis  (a) palmoplantar pustulosis  Common in females  Present as numerous, small, sterile pustules on erythematous plaques, B/L symmetrically on palms and soles  Affected area is dusky red and often scaly.  Removal of scale leaves a glazed dull-red surface.  Fresh pustules are yellow; older ones are yellow-brown or Dark Brown as pustule dries.  Desiccated pustule is exfoliated.  Pustules in all stages of evolution are seen
  • 19.  (b) acrodermatitis continua of hallopeau  Seen in children, more common in     females. Fingertips and toes show pustular lesions over glazed erythema and scaling Nails may be destroyed Osteolysis of distal phalanx can occur May evolve into generalized pustular psoriasis, especially in elderly Acrodermatitis continua with destruction of nail plate.
  • 20.  Generalized pustular psoriasis:  Triggered by pregnancy, sudden steroid withdrawal, infections, hypocalcaemia  Severe form  Characterized by multiple erythematous          plaques studded with tiny, sterile pustules that may coalesce to form lake of pus Uninvolved skin may shows erythema and pustules May a/w fever, arthralgia and malaise Pustules dry up and form scales or crusts Lesions develop in crops (a) acute (von Zumbusch) (b) of pregnancy (Impetigo herpetiformis) (c) infantile and juvenile (d) circinate, annular and linear (e) localized (not hands and feet). Acute generalized pustular psoriasis.
  • 21. Arthropathic psoriasis  Arthritis is seronegative & inflammatory  In 70% cases arthritis develops years after skin           changes In 10-15% cases precedes skin lesions RF –ve ,HLA-B7 & B27 commonly found Involve both peripheral joints & axial skeleton causing pain, stiffness and swelling Arthritis mutilans showing a/w Loss of joint space, periostitis & lysis of gross digital foreshortening terminal phalanges Clinically five type Asymmetric oligoarthritis - commonest type, <5 joints Symmetric polyarthritis - rheumatoid-like disease , >5 joints DIP joint arthritis ( most characteristic, but relatively rare), arthritis mutilans - causes destruction of bones Spondyloarthritis - axial skeletal involvement, peripheral oligoarthropathy with sausage-like digital swelling
  • 22. Variations by site  Scalp: (50%)  Diffusely or discreetly involved in form of Well difined, erythematous plaques with silvery white, thick scaling, usually no hair loss.  Sometimes, scaling is asbestos-like, being firmly adherent to scalp (pityriasis amiantacea)  Penis:  Solitary well-circumscribed reddish plaque without scales on glans of uncircumcised male.  Flexural (inverse) psoriasis (2-6%)  Lesions present over flexors and intertriginous areas( axilla, groin, umbilical region, inframammary folds)  Extremely erythematous and lack typical scaling.  More common in older adults than children  Difficult to differentiate from seborrhoeic dermatitis, intertrigo, erythrasma and candidiasis
  • 23.  Hands and feet:  Present as Diffuse hyperkeratotic, erythematous, plaques on which a fine silvery scale can be evoked by scratching;  A Sharply defined edge at wrist or forearm and absence of vesiculation are helpful.  On dorsal surface, knuckles frequently show a dull red thickening of the skin,  Nails: involved in 25 to 50% of cases.  Pits, ridges and grooves (psoriasis of nail matrix)  Onycholysis, subungual hyperkeratosis and splinter haemorrhages (involvement of nail bed or hyponychium)  Circular areas of discoloration of nail bed and hyponychium may resemble an ‘oil drop’ below nail  Thickened friable nail plate.
  • 24. Atypical forms      Digital and interdigital forms. Verrucous forms - affect legs. Follicular form - more common in elderly Lichenoid forms Linear forms  As a part of Koebner phenomenon.  Zonal lesions  Koebner reaction at site of herpes zoster  Seborrhoeic psoriasis  Mucosal lesions  True mucosal involvement is rare,  But has been a/w pustular, erythrodermic and plaque form  Ocular lesions  Blepharitis, conjunctivitis, keratitis, xerosis, symblepharon, trichiasis and Chronic uveitis have been recorded.
  • 25. PITYRIASIS ROSEA  Is an acute, self limiting skin eruption with distinctive        and constant course Incidence: .3-3% Age: 10-35 years Sex: M=F Etiology: Unknown Infections Picorna virus, HHV 6, HHV 7, Drug : e.g. Arsenic, Barbiturates, Gold, Bismuth, Captopril, Ketotifen, Metronidazole, D-penicillamine, Terbinafine may cause eruption similar to PR Atopy
  • 26. CLINICAL FEATURES May or may not be present . Located on trunk
  • 27. Within 10 day of herald patch, secondary plaques appears
  • 28. Pityriasis rosea: distribution of lesions on trunk in a typical fir tree appearance.
  • 29.  Atypical PR (20% of patients), herald patch may be missing or     confluent with other lesions. Distribution of rash may be peripheral, and facial involvement may be seen in children. Involvement of the axilla and groin (inverse variant) TYPES of lesion:  PR gigantea  PR urticata  Vesicular  Pustular  Purpuric  Erythema multiforme–like. Oral lesions of various types have been reported, including erythematous plaques, hemorrhagic puncta, and ulcers.
  • 30. LICHEN PLANUS
  • 31. ETIOPATHOGENESIS  Not clear, multifactorial  Infection: may be a/w syphilis, HSV2, HCV, amoebiasis, and chronic bladder infection  Psychosomatic: stress and/or anxiety are possibly a/w LP  Allergic: contact sensitizers and haptens may play a role in inciting LP  Immunologically mediated:  Primary site of immunologic reactivity may be basal keratinocytes whose new antigen are processed by langerhans cells and presented to helper / inducer T cells.  CMI is of primary importance in LP and humoral immunity is secondary  Genetic factors: increased incidence of HLA A3, A5, B7, HLA 28, HLA DR1, DR10, DRB1*0101 is seen
  • 32. Association of LP  With diseases of altered or disturbed immunity  Ulcerative colitis,  Alopecia areata,  Vitiligo,  Dermatomyositis,  Morphoea  Lichen sclerosus,  Systemic lupus erythematosus,  Pemphigus and paraneoplastic pemphigus,  Thymoma,  Myasthenia gravis,  Hypogammaglobulinaemia,  Primary biliary cirrhosis
  • 33. Histology          Compact hyperkeratosis. Wedge-shaped hypergranulosis Irregular acanthosis Focal increase in thickness of granular layer and infiltrate corresponds to presence of Wickham’s striae Degenerating basal epidermal cells are transformed into colloid bodies (15–20 µm) which appear singly or in clumps Rete ridges may appear flattened or effaced (‘saw-tooth’ appearance), and focal separation from dermis may lead to Max Joseph spaces Band-like infiltrate of lymphocytes and histiocytes, admixed with plasma cells obliterates DEJ. Epidermal melanocytes are absent or considerably decreased in number Pigmentary incontinence with dermal melanophages is characteristic.
  • 34. Lichen planus C/f:  Symptoms: Intensely itchy  Morphology: Shiny, Flat topped, polygonal, violaceous papules          of variable size (pinpoint to cms.) Wickham’s striae: fine whitish reticulated network present Scaling: Minimal Grouping: may remain descrete or may be arrnged in groups, in lines or in circles Site: Flexures and extremities (Wrists, shins); examine mucosa, scalp, nails Distribution: B/L symmetrical Mucous membrane involvement: Common (30 – 70%) White streaks forming a lacework on buccal mucosa are characteristic koebner phenomenon : common Papules resolve leaving hyperpigmentation
  • 35. Clinical variants Lesional morphology Hypertrophic LP Atrophic LP Guttate LP Follicular LP (Lichen planopilaris) Linear LP Annular LP Zosteriform LP Vesiculobullous LP Ulcerative (erosive) LP pigmentosus Site of involvement Mucosal (oral, genital) Palmoplanter Nail Scalp inverse Special form Actinic LP Lichen planus pemphigodes
  • 36. (30-70%, Oral up to 65%, genital 25%)
  • 37. SCALP LESIONS Follicular lesions of LP on scalp subside with scarring and result in cicatricial (scarring) alopecia
  • 38. nails show thinning, distal splitting, tenting of nail plate and pterygium formation, pterygium forms due to wingshaped prolongation of proximal nail fold onto nail bed, splitting and eventually destroying nail plate.
  • 39. Lichenoid drug eruption  Develop over weeks to month after starting        therapy Lesions larger Scaling prominent but Wickham’s striae absent Widely distributed but predilection for sun-exposed areas, face and upper trunk Mucous membrane involvement less common Residual hyperpigmentation common Alopecia: common H/P: focal parakeratosis, focal absence of granular layer, interface infiltrate is less dense and pleomorphic, colloid bodies are more numerous Drugs Heavy metals Antimalarials Antibiotics Antitubercular drugs Diuretics Antihypertensives Beta blockers ACEIs CCBs Anticovulsant NSAIDs Lipid lowering agents Isotretinoin Zidovudine Ranitidine Chlorpheniramine PUVA therapy
  • 40. Lichen nitidus  Rarer condition than idiopathic LP  Seen in children and young adults  Asymptomatic, monomorphic, tiny (pin point        to pin head sized), multiple, flat or dome shaped, skin-colored shiny papules Wickham’s striae: absent Usually discrete but may occur in Groups Seen on forearms, wrists, penis, abdomen, chest, buttocks and knees May be seen over palm and soles Koebnerization may be present Mucous membrane involvement: uncommon Healing occurs without scarring and pigmentary changes
  • 41.  Intense infiltrate situated     immediately below epidermis and is well circumscribed. Infiltrate consists of lymphocytes and histiocytes and few Langhans’ giant cells Overlying epidermis is flattened Liquefaction degeneration of basal cell Focally dense infiltrate containing a Rete ridges at margin of infiltrate few giant cells are elongated and tend to encircle it (claw clutching a ball)
  • 42. Lichen striatus  Self-limiting, inflammatory, linear dermatitis of            unknown origin Develop in lines of Blaschko Over 50% of cases occur B/w ages of 5 and 15 years, Females are affected two or three times more. Small, pink, lichenoid papules, discrete at first but rapidly coalescing, Appear suddenly and extend over course of a week or more to form a dull-red, slightly scaly, Linear band, usually 2 mm to 2 cm in width, Parallel linear or zosteriform Patterns may be seen No Wickham’s striae. Occur most commonly on one arm or leg, or on neck, but may develop on trunk. Involvement of the nails may result in longitudinal ridging, splitting, Onycholysis or nail loss Usually no symptoms, pruritic occasionally Course is variable.
  • 43. Seborrheic dermatitis  Chronic dermatitis,  Red, sharply marginated lesions covered with greasy    looking scales Distributed in areas with a rich supply of sebaceous glands, Dandruff (visible desquamation from scalp surface) appears to be the precursor of seborrhoeic dermatitis, and this may gradually progress through redness, irritation and increasing scaling of scalp to true seborrhoeic dermatitis. Involve scalp, face, presternal and interscapular regions, and the flexures. Lesions tend to be dull or yellowish red in color and covered with greasy scales.
  • 44. Clinical pattern of Seborrheic dermatitis
  • 45. Pityriasis Rubra Pilaris (PRP)  Uncommon Chronic papulosquamous disorder  Characterized by reddish orange scaly papules, acuminate         follicular papules and palmoplanter keratoderma Etiology Unknown in most patients. Familial in a few patients. Abnormality of vit. A metabolism and Immunological abnormality, bacterial and viral infections has been blamed Prevalence: 1 in 5000 population Age: Occurs in three age groups: early childhood (upto 10 Yrs0, late childhood (11 – 19 Yrs), adulthood in fifth decade Gender: adult M=F, children M>F
  • 46. Classification  Classical adult type. M/C type, seen in >50% cases, has cephalocaudal progression, good prognosis, spontaneous resolution in 80% within 1-3Yrs  Atypical adult type. 5% of cases, icthyosiform scaling scalp hair sparse, persists for long time  Classical juvenile type. Starts in first two Yrs of life, seen in10% cases, spontaneous resolution in 1-2 Yrs  Circumscribed juvenile type. Seen on elbows and knees, seen in 25% of cases  Atypical juvenile type. begins at birth or in first Yr of life, erythematous follicular hyperkeratosis and scleroderma like changes seen in hands and feet, seen in 5% cases, familial PRP  HIV associated PRP: shows pustular, acneform and nodulocystic lesions, elongated follicular plugs are seen
  • 47. Clinical Features  Widespread, small, acuminate follicular papules with           pinkish scales Coalesce to form plaques with islands of normal skin Present symmetrically on trunk and limbs Scalp shows diffuse erythema and scaling PRP begins at scalp and then descends down to whole trunk with islands of normal skin Dorsal aspect of proximal phalanges show follicular hyperkeratosis, surrounded by erythematous perifollicular halo Palpation of lesions give a sensation of nutmeg greater Scaling is fine and branny Palms and soles: yellowish orange hyperkeratosis with painful fissures Nails: thickened brittle with longitudinal ridging and splinter hemorrhage Oral mucosa rarely may show diffuse, lacy white plaques
  • 48. Pityriasis Lichenoides Course: chronic, remissions and relapses  Etiology Unknown, may be hypersensitivity to infectious agents.  Clinical Manifestations  Two clinical patterns recognized:  Pityriasis lichenoides et varioliformis acuta (PLEVA)  Constitutional symptoms like fever and arthralgia frequent.  Polymorphic eruption of multiple, erythematous, edematous papules, often surmounted by vesicles.  Pustules/hemorrhagic necrosis may develop  Lesions heal with hyperpigmented varioliform scars.  Trunk and flexures of extremities.  Pityriasis lichenoides chronica (PLC).  Polymorphic eruption of successive crops of asymptomatic red-brown papules, which are surmounted by a central, adherent mica-like Scale  Lesions heal with hypopigmentation.  Trunk and proximal part of extremities.
  • 49. pityriasis lichenoides et varioliformis edematous papules surmounted with hemorrhagic crust. Note scarring pityriasis lichenoides chronica: red brown papules surmounted by mica-like scales. Note hypopigmentation.
  • 50. Erythroderma (exfoliative dermatitis )  Erythroderma is the term applied to any inflammatory skin         disease that affects more than 90% of body surface. Incidence: 0.9 per 100 000 population Age: frequently seen in age group 40–60 years. Ichthyosiform variant seen in children. Gender: Male:female ratio of 2:1 Etiology Underlying skin diseases: Erythroderma can be a late manifestation in clinical course of several skin disease Idiopathic: no underlying cause can be determined.
  • 51.  Clinical Features  Extremely itchy.  In erythroderma secondary to other skin        diseases, there may be evidence of primary disease on clinical examination. Intense erythema and scaling Scales may be small or large and their color may vary from white to yellow. Associated features Alopecia, Shiny and beveled nails initially, Dystrophic nails and shedding of nails. Palmoplantar involvement with massive hyperkeratosis. Lymphadenopathy (in 50% of patients), Hepatomegaly and splenomegaly (occasionally). Lesions of underlying disease.
  • 52. Secondary syphilis  History of preceding high-risk sexual contact / genital ulcer  Maculopapular and papulosquamous lesions Associated features  Mucosal lesions  Coppery scaly papules on palms and soles  Condyloma lata  Lymphadenopathy  Serology for syphilis and dark ground microscopy: positive
  • 53. Discoid lupus erythematosus (DLE)  Symptoms: photosensitivity present  Morphology: annular lesions with central scarring and an erythematous halo  Scaling: adherent and prominent  Typical feature: follicular plugging  Site: face, ears; scalp, lip
  • 54. Parapsoriasis  Parapsoriasis is a controversial term used for a heterogeneous group of             dermatoses. Small plaque parapsoriasis: benign. Large plaque parapsoriasis: premalignant Etiology: Unknown. Prevalence: Uncommon. Age: Fifth decade. Gender: Male preponderance. Clinical Features Morphology Small plaque parapsoriasis Asymmetrical, yellow-erythematous, scaly plaques, which are small (<5 cm) and have digitating margins. Predominantly on covered parts of body (abdomen, buttocks, breasts and flexures). Runs a chronic course, usually responding to treatment and relapsing when treatment is stopped.
  • 55.  Large plaque parapsoriasis  Initially asymmetrical, erythematous, scaly plaques , quite similar to lesions of small plaque parapsoriasis except being larger (>5 cm) and more erythematous.  Presence of poikiloderma and induration in lesions suggestive of malignant transformation.  Predominantly on covered parts of body.  Course  Both variants run a chronic course; over period of time Large plaque parapsoriasis: erythematous, scaly, indurated plaques on covered parts of body.
  • 56. Morphology of papules/plaques in papulosquamous disorders Psoriasis Erythematous papules and plaques Lichen planus Violaceous papules with Wickham’s striae Pityriasis rosea Annular plaques Seborrheic dermatitis Yellowish, follicular papules Pityriasis rubra pilaris Erythematous follicular papules Secondary syphilis Dusky erythematous papules Pityriasis lichenoides et varioliformis acuta Erythematous edematous papules surmounted with vesicles/crust Pityriasis lichenoides chronica Erythematous papules surmounted with micalike scales
  • 57. Characteristics of scales in papulosquamous disorders Psoriasis Silvery scales Collarette of scales on leading edge Pityriasis rosea Seborrheic dermatitis Greasy scales Pityriasis lichenoides chronica Mica-like, adherent scales