Pityriasis rosea,lichenoides
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Transcript of Pityriasis rosea,lichenoides
PITYRIASIS ROSEA
PITYRIASIS LICHENOIDES BY AJAI SASIMALABAR MEDICAL COLLEGE
PITYRIASIS
• Any of several skin diseases marked by the formation and desquamation of fine scales
PITYRIASIS ROSEA
• Self limited dermatitis lasting from 4-7 weeks• Predominantly occur in adolscents and young
adults• May be asymptomatic or pruritic• Etiology unknown,viral origin has been
suggested
• Characterized by development of self limiting eruption
• Eruption preceded with large scaly annular plaque known as Herald patch or mother patch
• It is a raised Plaque• Within a week after heralad patch formation• Numerous oval shaped uniform papules and
macules with peripheral collateral scales appear abruptly(1-2cm of size)
• Distributed bilaterally symmetrically on • 1.Trunk• 2.Proximal portions of limbs
• On the back of trunk ,lesion show a fur tree or christmas tree like pattern
• Hanging curtain sign positive• When individual lesion is stretched along the
long axis ,the scales tend to fold across the lines of stretch
• Histological features• Focal parakeratosis• Mild acanthosis• Spongiosis• Exocytosis• Perivascular dermal infilitration with
lymphocytes
DIAGNOSIS
• Usually easily diagnosed by its morphology and distribution
• Can also occur as a manifestation of• 1.Secondary syphilis• 2.Drug reaction• 3.Internal malignancy(stomach)
TREATMENT
• Since self limiting ,no active treatment required
• Application of bland oils and avoidance of soap may relieve itching
• Severe itching -Oral antihistamines ,antipruritic lotions
PITYRIASIS LICHENOIDES
• Divided into two• 1.Pityrisis lichenoides chronica• 2.Pityriasis lichenoides et varioliformis acuta
(PLEVA) or Muscha-Habermann disease• They are two types of Parapsoriasis,other than
parapsoriasis en plaque
PARAPSORIASIS
• Includes a group of chronic,asymptomatic,maculopapular scaly eruptions of slow evolution
• Resistant to treatment
1.PITYRISIS LICHENOIDES CHRONICA
• Common type of parapsoriasis• Seen in children• Consists of discrete,scaly,erythematous• 1.Macules• 2.Papules• Papule shows a single layer of brownish scale• Removel of scale spoty hypopigmented
oval macule
Distribution – Bilaterally on sides of trunk and on thighs and upper arms
• Difference from psoriasis• 1.When one tries to remove the brownish
scale,it comes out as a wholeand not in layers• 2.Auspitz sign absent
Auspitz sign
• When scales are scrapped off completely in psoriasis patient ,the basement membrane is exposed and is seen as moist red surface
• Through which dilated capillaries are seen as red spots
• On further scrapping these capillaries at tips of elongated papillae are torn leading to multiple bleeding points(auspitz sign)
TREATMENT
• No active treatment indicated• Bland emollient application beneficial• Oral Tetracycline and PUVA therapy has been
reported effective
2.Pityriasis lichenoides et varioliformis acuta (PLEVA)
• Abrupt onset• Consists of erythematous
macules,papules,necrotic lesions,and few vesicles
• Eythematous papules tend to• 1.Crusting• 2.Necrosis• 3.Hemorrhage
• Distribution- trunk,flexor surface of upper extremities and the axillae
Histological features
• Dense lymphocytic perivascular infilitration in supficial dermis
• Erythrocytes trapped within epidermis
• Lesions heal leaving depressed varioliform (resembling smallpox) scar
• New lesions may erupt and disease can be chronic or subacute
TREATMENT
• Methotrexate• Tetracycline• Erythromycin• PUVA- May give relief in some patients
THANK YOU