<prompt> All are true regarding cryptococcal infection, except -Occurs in immunodeficient statesCapsular antigen in CSF is a rapid method of detectionAnticapsular antibody is protectiveUrease ve  <response>: Ans. is c i.e., Anticapsular Antibody is protective CRYPTOCOCCUS NEOFORMANS . The only pathogenic yeast . Four capsular serotypes - A, B, C and D . It has polysaccharide capsule . Most infections in immunocompromized patients are caused by serotype A. . Pigeon droppings commonly contains serotype A and D. . Eucalyptus tree contain serotype B. . It is urease positive. Mode of transmission - By inhalation of the fungus into the lung most common - Through skin or mucosa some times. Laboratory diagnosis -Lumbar puncture is the single most useful diagnositc test Laboratory diagnosis Direct microscopy . Unstained wet preperations of CSF mixed with drop of India ink or nigrosine demonstrate the capsule as a clear halo Methenamine silver or periodic acid-Schiff are used for staining a tissue sample. Culture . Can be easily cultured from CSF on sabourouds agar Serology . The most useful serological test is LPA test Latex agglutination test for the detection of cryptococcal polysaccharide capsular antigen . This is highly specific and sensitive; and gives better results than direct microscopy and cultures. Culture . Can be easily cultured from CSF on sabourouds agar 