Risk factors for intussusception in infants in Vietnam and Australia: adenovirus implicated, but not rotavirus.

OBJECTIVE: This study aimed to investigate risk factors for the development of intussusception in infants in a developing country with a suspected high incidence and in a developed country with a low incidence. STUDY DESIGN: A prospective case-control study of infants <2 years of age with idiopathic intussusception confirmed by air enema or surgery was conducted at the National Hospital of Paediatrics (NHP), Vietnam (n = 533) and the Royal Children's Hospital (RCH), Australia (n = 51). Diagnosis was validated in a subset (84% NHP; 67% RCH) by an independent blinded radiologist. Risk factor assessment was performed using a standardized questionnaire. Stool specimens were assayed for bacterial, viral, and parasitic agents. RESULTS: The incidence of intussusception in Vietnam was 302/100,000 in infants <1 year of age (95% CI: 258-352), substantially higher than in Australia (71/100,000). A strong association with adenovirus infection was observed at both sites (cases positive at NHP: 34%, OR 8.2; cases positive at RCH: 40%, OR 44). No association was identified between intussusception and rotavirus, other enteric pathogens, oral polio vaccine, feeding practices, or living conditions. CONCLUSIONS: The incidence of intussusception in infants was markedly higher in Vietnam than in Australia. A strong association between adenovirus infection and intussusception was identified at both sites suggesting that adenovirus may play a role in the etiology of intussusception.

Energy metabolism in infants with cystic fibrosis.

OBJECTIVE: To determine whether a defect in energy metabolism exists in infants with cystic fibrosis (CF). DESIGN: Unselected, newly-diagnosed subjects with CF (n = 46) and 24 healthy infants aged <20 weeks had measurements of resting energy expenditure (REE), total energy expenditure (TEE) (n = 25), and body composition. Metabolizable energy intake (MEI) was calculated. Genotype, energy intake, and pancreatic status was determined in all subjects with CF, and 24 underwent bronchial lavage. RESULTS: At diagnosis, infants with CF detected by newborn screening had significant anthropometric deficits (mean [SD] z-weight = 0.5 [1.0], z-length = 0.7 [1.3]) associated with pancreatic insufficiency. Their REE, TEE, or MEI (absolute measurements, per unit body weight or fat-free mass) were not increased. No relationship between REE, TEE, or MEI and Delta F(508) genotype, and no proportional differences in individual components of MEI between subjects with CF and controls, or between subjects with CF who were homozygotes or compound heterozygotes for Delta F(508) were observed. REE and TEE were not correlated with bronchial infection or inflammation. CONCLUSION: Growth impairment during the first weeks of life in infants with CF is associated with pancreatic insufficiency. However, there is no evidence for a defect of energy metabolism related to Delta F(508), and in infants with CF, minimal lung disease is unaccompanied by increased energy expenditure.