Diarrhea in solid organ transplant recipients in the South Asian Region - Expert group opinion for diagnosis and management

Diarrhea after solid organ transplantation is a common problem. Posttransplant diarrhea can lead to dehydration, weight loss, graft dysfunction, frequent hospitalization and increased mortality. Posttransplant diarrhea is seen in 20%–25% of patients within 2 years of transplantation and it can be both due to infections and the drugs. The most common cause of drug causing diarrhea is mycophenolate mofetil, and tacrolimus. The common infective causes of diarrhea in posttransplant recipients include viral infections (norovirus, sapovirus, cytomegalovirus [CMV]), bacterial infections (Salmonella, Clostridium difficile, Aeromonas, Campylobactor, Enterotoxigenic, and Enterohemorrhagic Escherichia coli) and parasitic infections (Cryptosporidium, Giardia lamblia, Microsporidia Cyclospora, Strongyloidiasis etc.). Because of overall poor hygienic conditions, infective diarrhea is common in South Asian region. Since most cases of acute diarrhea are infective, and many with viral etiologies, conservative management using oral rehydration solution, antidiarrheal drugs, and where appropriate, a short course of antibiotics helps in the resolution of most cases. A detailed evaluation should be performed in patients with chronic diarrhea, recurrent diarrhea, and those with graft dysfunction. The evaluation of diarrhea should include stool microscopy for ova and cysts, special stains for opportunistic parasitic infection, and molecular diagnostic tools like multiplex Polymerase chain reaction. Colonoscopic and upper gastrointestinal endoscopic examination with biopsies are required to investigate for CMV infection, malabsorption syndrome, inflammatory bowel diseases and posttransplant lymphoproliferative disorder. Although the causes of diarrhea are numerous, an algorithmic approach should be followed both for the diagnosis and the treatment of diarrhea in an organ transplant recipient.