<prompt> A patient with AIDS returned from Haiti with acute diarrhea. The stool revealed an oval organism 8 to 9 um in diameter that was acid-fast and fluoresced blue under ultraviolet light. The most likely identification of this organism isCyclosporaGiardiaCryptosporidiumEnterocytozoon  <response>: Coccidian-like bodies have been identified in stools of some patients with diarrhea. These organisms appear to be similar to blue-green algae and were referred to as Cyanobacterium-like until they were recently reclassified as Cyclospora. They are larger than the microsporidia and resemble neither Giardia nor Prototheca nor other algae-like organisms. Unlike Cryptosporidium, these organisms fluoresce under ultraviolet light Reference: Ananthanarayan and Paniker;s Textbook of Microbiology Tenth edition 