This report refers to a patient of unknown age enrolled in a study. The aim of this study was to describe the effects of rotavirus vaccination on weight again and gastrointestinal losses in infants with functional short gut syndrome secondary to an ileostomy. A retrospective review of all infants with an ileostomy who received ROTATEQ while hospitalized from 2007 and 2009 was done. Infants with an ileostomy were considered eligible if they received ROTATEQ, Oral before discharge from the Neonatal Unit (NNU). As a result from the study, nine infants received full enteral feeds and were vaccinated with ROTATEQ, Oral during their admission. Of these infants, seven were born extremely preterm and required an ileostomy after developing necrotising enterocolitis. All infants were cardiovascularly stable prior to vaccination and fully enterally fed. The ileostomy was fashioned at a median (range) age of 19 (2, 67) days. The first dose of ROTATEQ, Oral was administered at 65 (61, 99) days. Three infants (Infant 1, 3 and 7) developed higher ileostomy fluid losses on the day of, or shortly after, vaccination and persisted into the second week. The stoma was closed in infant 79 days after vaccination because of ongoing excessive fluid losses. The infant had necrotising enterocolitis and 2 cm of his terminal ileum was resected, surgery performed at 9 days old. Patient was fed with alfare and oral rehydration solution. He received two oral ROTATEQ vaccinations. After the first vaccination, (first dose was given at 99 days old) he developed a brief period of severe ileostomy losses requiring fluid resuscitation. His ileostomy losses were 76 mL/kg/day in the 24 h after vaccination but rapidly normalised after fasting for the remainder of the 2 weeks postvaccination. On the day of his first vaccination, his temperature was greater than 38 degrees C. Blood culture performed at that time was sterile. After the second dose of oral ROTATEQ, his stomal losses transiently increased by 20 mL/kg/day on days 7 and 8. Oral ROTATEQ was isolated in his stool 7 days after the second vaccination. This infant was subsequently discharged home with an ileostomy. The response of infant 3 highlights the potential risks with ROTATEQ vaccination. We therefore suggest that infants with short gut syndrome be vaccinated in a secondary or tertiary neonatal unit. Infant 3 was vaccinated twice during the audit period. This infant was also the least tolerant to ROTATEQ overall. After both vaccinations, he developed transient very high ileostomy losses. Interestingly, rotavirus was isolated from his stool. The virus isolated may be vaccine related. Molecular typing to differentiate between a vaccine or wild-type rotavirus strain was not performed. No other infants in the nursery developed diarrhoea or vomiting around the same time, and as such, stool testing on other infants was not performed. Faecal shedding of rotavirus vaccine virus has been documented in large international trials. Vaccine virus was detected in approximately 9% of ROTATEQ recipients after first dose and rarely after subsequent doses. Shedding of virus occurred between day 1 and day 15 after vaccination. The authors discussed oral ROTATEQ contains five live human-bovine rotavirus reassortant with human serotypes G1-4 and P1 and bovine serotypes G6 and P7. Although the absolute number of infants with an ileostomy was comparatively few, they were at risk of major complications because of infective diarrhoea. In our small case series, oral rotavirus vaccination was well tolerated in most infants. The potential for significant intestinal fluid losses cannot be discounted after rotavirus vaccination and suggests that vaccination requires close monitoring in this population. This is one of several reports from the same source (MARRS# 1207AUS005018, MARRS# 1207AUS007132). Additional information has been requested.