<prompt> Coral red color on Woods lamp is seen inErythrasmaTuberous sclerosisPityriasis rosaeTinea corporis  <response>: Ans. a Erythrasma Ref. Harrison 18th p 289DD of erythrasma1ConditionOrganismSymptomsMorphologyDiagnosisTreatment2ErythrasmaCorynebacteriumminutissimumOften asymptomatic- pruritus intertriginous areasWoodss light shows coral-red fluorescenceTopical: erythromycin 2, clindamycin 1 or keratolytic agentsOral: erythromycin or clarithromycinIntertrigoCandida albicansErythematous pustules, papules andor plaques - satellite lesions at periphery pruritus paintenderness intertriginous areasKOH examination shows septate hyphae and pseudohyphaeTopical: allylamines, azoles, ciclopirox, nystatinOral: azolesTinea corporisEpidermophyton species,Microsporum species,Trichophyton speciesAnnular scaly erythematous plaques often with central clearingKOH examination shows segmented hyphaeTopicals: allylamines, azoles, ciclopiroxOral: azoles, griseofulvin, terbinafine hcl1Abbreviations: KOH, 10 potassium hydroxide preparation; , present; not present.2This is only a partial therapeutic agentsWOODS LIGHT A Woods lamp generates 360-nm ultraviolet or black light that can be used to aid the evaluation of certain skin disorders. MHSSCET 2009 Normally the skin does not fluorosence or shine under ultraviolet light.The different infections and conditions showing different colors are:DiseaseColor on Woods Lamp 360 nm uV light used1Erythrasma Corynebacterium minutissimumCoral red color2Tinea versicolorGolden yellow3Tinea capitis Microsporum canis or M. audouiniYellow fluorescence4Trichophyton schoenleiniPale green5Microsporum audouinii or M. canisYellow fluorescence6Pseudomonas aeruginosaPale blue Aquagreen1Tuberous sclerosisAsh-leaf-shaped spot8Porphyria cutanea tardaPink to pink-orange9LeprosyBlue white10HypopigmentationPale white11HyperpigmentationPurple brown12Depigmentation - VitiligoTotally white13AlbinismBright white14Pigmented lesions of the epidermis such as frecklesAre accentuated under a Woods light15dermal pigment such as postinflammatory hyperpigmentationFades under a Woods lightAdditional Educational points:Q. Ans.1White dermographismAtopic dermatitis2Dennies line extra fold of skin beneath lower eyelid perioral pallorAtopic dermatitis3Winter itch,Asteatotic eczema4Cradle capSeborrheic dermatitis5Fir tree-like appearancePityriasis rosea6Interface dermatitis, Wickhams striaeLichen planus7Spaghetti and meatballs KOH preparationMalassezia furfur 