Ans. is 'c' i.e. Henoch Schonlein purpura First, what is Leukocytoclastic vasculitisLeukocytoclastic vasculitis- *It is a cutaneous acute vasculitis characterized clinically by palpable purpura especially of the legs and histologically by the presence of leukocytoblast (Leukocytoblast are nuclear debris of neutrophils)This is the definition of leukocytoclastic vasculitis given in Dorland's dictionary, but according to Harrison the term leukocytoclastic vasculitis can be used interchangeably with the term hypersensitivity vasculitis and predominantly cutaneous vasculitis Harrison further adds that none of the term is adequate due to heterogenicity of this group of disorder.Now the causes of leukocytoclastic vasculitis: -Drug induced vasculitis*Henoch Schonlein purpura*Systemic lupus erythematosis*Rheumatoid arthritis*Sjogren's syndrome*Essential mixed cryoglobulinemia*SABE*EBV infectionHIV infectionChronic active hepatitisUlcerative colitisRetro peritoneal fibrosisPrimary biliary cirrhosisSo the answer is obvious, none of the options given in the question cause leukocytoclastic vasculitis except H.S. purpuraMore about leukocytoclastic vasculitis:Pathological features: -Vasculitis of small vessels* (post capillary venules are most commonly involved)Leukocytoclastic is present - (leukocytoblast are nuclear debris remaining from the neutrophils)Immune complex deposition - It is considered to be the immuno pathogenic mechanism* of this type of vasculitisClinical featuresThe hallmark of this group of vasculitis is the predominance of skin involvement. The skin lesions appear asPalpable purpura (M.C. skin involvement)MaculesPapulesVesiclesBullaeOther organ system may also be involved to varying degrees * Laboratory diagnosisNo specific laboratory tests for this group of vasculitis. Only nonspecific features such as mild Leucocytosis with or without eosinophilia and elevated ESR is seen.