Increased plasma tryptophan in HIV-infected patients treated with pharmacologic doses of nicotinamide

OBJECTIVE

Decreased plasma tryptophan in persons infected with human immunodeficiency virus (HIV) was first reported over a decade ago, and this observation has since been confirmed by many groups. Before this study, only zidovudine (an antiviral medication) had been reported to reverse plasma tryptophan depletion in HIV-infected persons. Starting with the hypothesis that HIV induces a pellagra-like state and that plasma tryptophan in HIV-infected patients is decreased as a known biochemical correlate of pellagra, we predicted that niacin therapy would reverse plasma tryptophan depletion as it does in pellagra.

METHODS

After receiving approval from the institutional review board, we treated HIV-infected patients for 2 mo with high-dose niacin in the form of oral nicotinamide.

RESULTS

There was an average 40% increase in plasma tryptophan (P = 0.01) in the four HIV-infected individuals who completed the 2-mo protocol. This finding was specific in that four other amino acids, which have been shown to have significant plasma concentration alterations during HIV infection (i.e., cystine, methionine, taurine, and lysine), showed no significant change with nicotinamide therapy.

CONCLUSIONS

There were no adverse side effects attributable to this treatment. The effects of high-dose nicotinamide treatment on morbidity or mortality in HIV-infected persons are yet to be determined. This report marks the first successful use of a vitamin to reverse this HIV-induced metabolic abnormality.

Reporting of MMR evidence in professional publications: 1988-2007

OBJECTIVE

To examine how journals and magazines disseminate research evidence and guidance on best practice to health professionals by aligning commentaries on measles, mumps, and rubella vaccine (MMR) evidence in journals with key events in the MMR controversy.

DESIGN

Content analysis.

DATA SOURCES

Comment articles in six commonly read UK publications.

MAIN OUTCOME MEASURES

Number of comment pieces by publication, year and article type; trends in the focus, tone and inclusion of recommendations on MMR.

RESULTS

860 articles met the inclusion criteria (BMJ n = 104, Community Practitioner n = 45, Health Visitor n = 24, Practice Nurse n = 61, Nursing Standard n = 61 and Pulse n = 565). Of these 860 comment pieces, 264 made some reference to evidence endorsing the safety of MMR. Around one in 10 were rated as negative (10.9%, n = 29) or neutral (11.3%, n = 30) in relation to MMR safety, and nearly a quarter (22.7%, n = 60) were rated as mixed. Following the publication of Wakefield et al's 1998 paper there was a period of neutrality. In 2000, despite growing public concerns and widespread media coverage, fewer than 20 comment pieces were published. Less than a quarter of comment pieces (n = 196, 22.7%) included recommendations.

CONCLUSION

While a period of neutrality may reflect a professional response to uncertainty by holding back until consensus emerges, it may also represent a missed opportunity to promote evidence-based practice.

Neonatal Abdominal Aortic Thrombus

Umbilical artery catheterization is considered the standard of care for arterial access in neonates. Studies have shown, however, that umbilical artery catheterization carries a high risk of aortic thrombosis, which can be fatal. Neonatal aortic thrombosis can be difficult to treat appropriately, in part because of the absence of reliable data for this patient population and nonstandardized reporting of the condition. Sonography of the abdominal aorta in neonates provides a noninvasive means of diagnosing the presence and extent of aortic thrombus, which assists in managing the patient’s plan of care. An important case also has been made for long-term follow-up studies using sonography as the diagnostic tool in patients who received umbilical artery catheters as infants.