A case report of severe diarrhea due to cytomegalovirus infection after living donor liver transplantation: successful treatment with butyrate-producing bacteria, immunosuppressive adjustments, and anti-cytomegalovirus therapy.

Purpose: In recent years, the benefits of probiotics for perioperative management have been recognized, and butyrate-producing bacteria are attracting attention as new beneficial intestinal bacteria. The present study reports a case of cytomegalovirus (CMV) infection and frequent watery diarrhea caused by immunosuppressants after living donor liver transplantation, wherein administration of butyrate-producing bacteria was considered effective. Case: The patient was a 75-year-old woman presenting with the chief complaints of weight loss and generalized muscle weakness. History of present illness: Seven years ago, the patient underwent living donor liver transplantation with her daughter as the donor at University Hospital A for liver cancer concurrent with cirrhosis. Following the postoperative outpatient visit, the patient was admitted to a local geriatric care facility because of her advanced age; however, she was urgently rehospitalized at the same university hospital for acute renal failure caused by decreased food intake and diarrhea. Although intensive care saved her life, she was admitted to our hospital for nutritional management and rehabilitation because of considerable weight loss and generalized muscle weakness caused by disuse syndrome resulting from prolonged bed rest. At admission, she was 142 cm tall, weighed 39.5 kg, and had a body mass index 19.6. She was unable to stand up unassisted or transfer to a wheelchair and remained in bed. After admission, central venous nutrition and rehabilitation therapy were initiated. However, on day 10 of admission, she abruptly developed watery diarrhea that occurred 12 times/day, with a blood test showing strong positive results for CMV antigen. Consequently, immunosuppressive drugs were reduced, valganciclovir was administered as an anti-CMV drug, and butyrate-producing bacteria were administered as a probiotic. Subsequently, the watery stools improved, and the frequency of defecation decreased to 4 times/day within 3 weeks after treatment initiation. One month later, she had normal stools twice daily, and CMV antigen results were negative. After her nutritional status improved, the patient was transferred to a different hospital. Conclusion: We experienced a case in which butyrate-producing bacteria effectively treated a patient with watery diarrhea following liver transplantation.