Severe gastrointestinal cryptosporidiosis three years after multi-visceral transplantation

Background: Cryptosporidia are known to cause opportunistic gastrointestinal tract infections with variable severity. Such infections can be life-threatening in transplant recipients. We report the evolution of cryptosporidiosis in a multi-visceral transplant recipient with repeated endoscopic biopsies until specific therapy was instituted. Case description: A 40-year-old woman with a history of multi-visceral (stomach, duodenum, small bowel, liver, and pancreas) transplantation presented with severe acute diarrhea three years after transplantation. Endoscopic biopsies of the stomach, duodenum, and lower small bowel were performed and submitted for histologic examination to assess the possibility of rejection. Microscopic examination of the lower small bowel biopsy specimens revealed mild to moderate inflammation and the presence of microorganisms with features of Cryptosporidia in the intestinal crypts. No evidence of rejection was found. While waiting for the availability of nitazoxanide, the patient was initiated on metronidazole, but her diarrhea worsened. Eleven days later, new biopsies were obtained, revealing abundant Cryptosporidia in the lower small bowel and duodenal specimens and few Cryptosporidia in the gastric biopsy specimen. Nitazoxanide was soon administered, leading to clinical improvement. Six weeks later, new biopsies showed complete resolution of inflammation and the absence of microorganisms. Conclusion: Histological examination of biopsy specimens is crucial for the diagnosis of cryptosporidiosis, which can threaten the life of immunocompromised individuals. The importance of specific antiprotozoal treatment must be emphasized.