Mitochondrial disorders among infants exposed to HIV and antiretroviral therapy.

Although antiretroviral therapy (ART) is critical for preventing mother-to-child transmission of HIV, concern has been raised about the possibility that it may cause mitochondrial dysfunction in infants. There is adequate evidence for a mechanism by which exposure to nucleoside reverse transcriptase inhibitors (NRTIs) could lead to mitochondrial dysfunction; animal studies have shown evidence of mitochondrial dysfunction in the offspring of animals treated with NRTIs and mitochondrial disorders occur in adults treated with NRTIs. This systematic review synthesises the published research on mitochondrial dysfunction and disorders in infants exposed to HIV and antiretrovirals. We found conflicting evidence regarding the possible association of in utero ART exposure with mortality and morbidity due to mitochondrial dysfunction. ART exposure in utero or postpartum was associated with persistent decreases in lymphocytes, neutrophils and platelets as well as an increased risk of transient lactic acidaemia, anaemia and mitochondrial DNA depletion, although these laboratory findings were generally not associated with clinical symptoms. We conclude that large, prospective studies of HIV-exposed infants are needed to resolve the discrepant results regarding morbidity and mortality related to mitochondrial disorders, to ascertain the clinical significance of effects on laboratory values, to determine whether or not the incidence of mitochondrial disorders differs by regimen and to develop predictive models that might identify which infants are at the greatest risk. The challenges that remain to be addressed include the development of a sensitive but affordable screening algorithm in combination with specific diagnostic criteria; consistent collection of data on ART exposure and other risk factors, long-term follow-up of HIV-exposed but uninfected children and implementation in resource-limited settings.

Resource utilization associated with irritable bowel syndrome in the United States 1987-1997.

This study uses national databases to examine the impact of irritable bowel syndrome (IBS) on resource utilization in the United States. Approximately 1.5-2.7 million physician visits (599-1,043 per 100,000) yearly were related to IBS, with 45.3% seen by gastroenterologists, and 89% prescribed medications. Rates of physician visits by women were approximately 2.4-3.3 times higher than that for men. The average number of medication prescribed per visit was 1.83. Approximately 89% of the visits were prescribed with medications. The rate of hospitalization (5.1 per 100,000 in 1997) decreased by 60% and length of stay decreased from 5.5 to 3.1 days in the past decade. The average charges of IBS-related hospitalization were US$7,882. Our study found an apparent decreasing trend of IBS-related hospitalizations and no marked increase in office consultations in the past decade. However, a better case identification criterion is necessary to estimate the true disease burden.