Ans. d Lichen nitidus (Ref: Mark Lebwohl 2nd/345)A young 8 years old boy with multiple, small, pin point, shiny, papular lesions on dorsal aspect of hand, forearms and his penis also. Diagnosis is Lichen nitidus.Grouped pinhead lesions on elbow. abdomen, penis and dorsum of hand in a child as shown in the picture is highly suggestive of lichen nitidus.Lie hen scrofulosorum is an uncommon asymptomatic lichenoid eruption of minute papule occurring in children and adolescents with strongly positive tuberculin reaction. It mainly involves perifollicular distribution on abdomen, chest, back and proximal limbs. A hallmark is that superficial epitheloid dermal granuloma surround hair follicles and sweat ducts and may occupy several dermal papillae. Lichen NitidusLesion and etiology are similar, but size is smaller 1.2 mm (pinhead sizeQ)Occurs as grouped lesions on elbow, abdomen, penis and dorsum of handQMucosal or nail changes are rareSelf limiting, non-itchyQHistopathology:Dense, circumscribed and distinctive infiltrate of histio-lymphocytic cells situated directly beneath thinned epidermis results in widening of papillary dermis with elongation and the appearance of embracement by neighboring rete ridges ( Ball in clutch appearanceQ).Thinned epidermis demonstrates central parakeratosisQ, variable /focal hyper keratosis without hypergranulosis, minimal hydropic degeneration and few dyskeratotic cellsTreatment:Antihistaminics particularly AstemazoleQ is effective. Lichen ScrofulosorumLichen scrofulosorum is a lichenoid eruption of minute papulesQOccurs in children and adolescents with tuberculosis.Pathogenesis:Usually associated with chronic tuberculous disease of the LNs and honesQClinical Features:Eruption is asymptomatic and is usually confined to the trunkQ.Lesions consist of symptomless, small, firm, follicular or parafollicular papules of a yellowish or pink color with flat-top or bear a minute homy spine or fine scales on their surfaceQ.It mainly involves perifollicular distribution on abdomen, chest, back and proximal limbsQ.Histopathology:A hallmark is that superficial epitheloid dermal granuloma surround hair follicles and sweat ducts and may occupy several dermal papillaeQ.Treatment:Antituberculous therapy results in complete resolution within a matter of weeksQ.FeatureLichen NitidusLichen planusSymptomsAsymptomaticItchy (marked)Cutaneous lesionMultiple, discrete (or closely grouped), minute, pinpoint to pinhead sizedQ (1- 2mm), flat/ round or dome shaped papule with a glistening (shiny surface)Q.Papules are flesh colored or pink or shiny hypopigmentedQ (in blacks)Larger, plain (flat) topped, polygonal, pruritic, pink/purple (violaceous) papuleQWickham's striaeAbsentPresentQGroupingPresentQUsually notMucous membrane involvementUncommonCommonQ (Variably present)SiteMost frequently on flexural surfaces of upper extremities i.e. arm. forearm, wrist and dorsal surface of hands, lower abdomen, breast, the glans and shaft of penis and other areas of genital regionQFlexures (wrist), extremities (shin), lower back and genitalsQ