Which of the following stains positive with modified AFB stain?: (A) Bacilus anthrax, (B) Corynebacterium diphtheriae, (C) Cryptosporidium parvum, (D) Actinomycetes
Answer is C. Ans. c (Cryptosporidium parvum) (Ref. Ananthanarayan microbiology 6th ed. 371; Harsh Mohan Pathology 4th ed., 32)ACID FAST STAINING IS POSITIVE WITH-# Mycobacterium tuberculosis# Mycobacterium leprae# Nocardia# Cyclospora# Cryptosporidium parvum (Modified AFB stain)# Isospora (Modified AFB stain)# Bacterial spores# Lipofuschin pigment# Rodococcus equi- Lipofuschin is wear and tear lipid pigment in cells and can be stained by fat stains but differs from other lipids in being fluorescent and acid fast.- Acid fastness of tubercle bacillus is a scribed to the presence in the bacillus of an unsaponifiable wax (Mycolic add) or to a semi-permeable membrane around the cell. It is related to integrity of the cell and appears to be a property of lipid-rich waxy cell wall.