Rotavirus Gastroenteritis Leading to Secondary Bacteremia in Previously Healthy Infants: In Reply

To the Editor.—We read with interest the article “Secondary Bacteremia After Rotavirus Gastroenteritis in Infancy,”1 in which Lowenthal et al described 4 cases of confirmed rotavirus gastroenteritis complicated by secondary enterobacterial bacteremia in previously healthy infants aged from 2 weeks to 13 months. Rotavirus is the single most important cause of severe, dehydrating gastroenteritis in infants and young children worldwide and is associated with high morbidity and mortality, especially in developing countries. Despite an estimated annual incidence of ∼130 million cases,2 secondary bacteremia after rotavirus gastroenteritis has seldom been reported.1,3,4 We aim to describe the prevalence rate and clinical characteristics of rotavirus gastroenteritis with secondary bacteremia in infants and toddlers in our setting.We conducted a retrospective analysis on all children admitted to the Hospital Sant Joan de Déu (Barcelona, Spain) with rotavirus gastroenteritis from January 1997 to March 2006. Cases of secondary bacteremia were considered according to the following inclusion criteria: (1) previously healthy children aged from 29 days to 5 years; (2) negative blood, urine, and/or stool cultures and positive for fecal rotavirus antigen (Rota-strip; Coris Bioconcept, Gembloux, Belgium) at admission; and (3) ulterior positive blood culture for occurrence of bacteremia.Overall, 891 cases of rotavirus gastroenteritis were identified during the study period (female gender: 39.8%; median age at admission: 8 months [range: 1–59 months]). Only 2 of these patients fulfilled the stringent inclusion criteria (prevalence rate: 0.22%; 95% confidence interval: 0%–0.54%). Patient 1 was a 6-week-old male infant referred because of 1 day of fever and watery diarrhea without blood or mucus. Physical examination only disclosed mild dehydration. Blood, urine, and stool cultures at admission were negative; rotavirus antigen was detected in his stool. The infant remained afebrile, and his general condition improved rapidly after intravenous rehydration. Three days later, his fever rose to 39.3°C. Blood, urine, and cerebrospinal fluid cultures were obtained, and 2 blood-culture bottles yielded Streptococcus viridans. A 7-day treatment with intravenous cefotaxime was administered, with complete recovery. Patient 2 was a 10-month-old male infant referred because of loss of appetite and diarrhea starting 1 week before presentation. At admission, the patient appeared moderately dehydrated, with a swollen abdomen and increased peristalsis. Stool was free of blood and mucus and tested positive for rotavirus antigen. Initial laboratory data revealed normal blood count and C-reactive protein and electrolyte levels and mild metabolic acidosis; blood and stool cultures were negative. Intravenous fluids were started, and improvement of his hydration status was observed. At hospitalization day 5, his fever rose to 38.3°C and blood culture grew Enterobacter cloacae. The infant was treated with a 14-day course of intravenous piperacillin-tazobactam, with an uneventful recovery.Only 8 cases of secondary bacteremia after rotavirus gastroenteritis have been described in the literature.1,3,4 As stated by Lowenthal et al,1 its clinical course is typical of secondary bacterial complications after other viral infections and usually caused by endogenous bacterial flora from the small intestine. Most patients are under the age of 12 months and recover fully after intravenous antibiotic treatment. In our opinion, the low prevalence rate we report (0.22%) supports the hypothesis that this condition probably remains underdiagnosed because blood cultures are not obtained when recrudescent fever, thought to be caused by rotavirus infection, occurs. Pediatricians should be aware of this threatening complication of rotavirus gastroenteritis.