<prompt> Heroin abuse causes ?Focal segmental glomerulonephritisCresent glomerulonephritisMembraneus glomerulonephritisDiffuse glomerulonephritis  <response>: Answer- A. Focal segmental glomerulonephritisClinically it presents as nephrotic syndrome.CausesHIV infectionHeroin addictionSickle cell diseaseMassive obesityIgA nephropathyReflux nephropathyIdiopathic 