May 2018 News of Possible Interest

Doc Gumshoe with news on antibiotics, prostate cancer, and migraines

No, these bits won’t be about Melania’s kidney ailment nor yet about what Meghan wore for The Wedding.   I wish them both luck – they’ll need it!. However, there continue to be developments on the medical and health-care fronts that may matter to us a good deal more than the doings of those ladies.   

The first one is especially interesting in that it poses the need to balance considerations that have potential impact on the lives of millions.   Here’s the story.

Antibiotics given prophylactically save the lives of children in poor regions

This was based on a study in three African nations – Malawi, Niger, and Tanzania.   (Keenan JD et al.   “Azithromycin to reduce childhood mortality in sub-Saharan Africa,” N Engl J Med 2018;378:1583-1592)  A total of 1,533 communities in those three nations were randomized such that young children in these communities received either four twice-yearly single doses of azithromycin or placebo.   All-cause mortality in these children was the single outcome measure. Children were not followed as individuals; the comparisons were between communities as a whole. The total number of children up to 5 years of age in those communities was 190,238, of which approximately 90% participated in the trial.    

The single azithromycin dose was approximately 20 mg per kilogram of body weight.   The usual starting dose of azithromycin is 500 mg, followed by 250 mg per day for four more days.   At the 20 mg per kilogram of body weight used in the study, 500 mg would be the dose for a child weighing 25 kilograms, or about 55 pounds.    I would judge that the dosage was quite robust for a single prophylactic dose, especially for the younger children in the study.

Overall mortality was 13.5% lower in children in the communities that received azithromycin compared with children in communities that received placebo; this was a highly significant difference (P < 0.001).   The rate was 5.7% lower in Malawi, 18.1% lower in Niger, and 3.4% lower in Tanzania.   

The overall difference was especially notable in children in the age group of 1 to 5 months.   In those children, the mortality rate was 24.9% lower in the communities that received azithromycin compared with communities that received placebo.

Azithromycin, (Zithromax, from Pfizer) is an antibiotic in the macrolides class, which includes clarithromycin, erythromycin, and others.   Like many antibiotics, it was developed based on a soil-dwelling bacterium. Macrolides, including azithromycin, are effective against a broad range of gram-positive pathogens, including many that cause upper- and lower-respiratory illnesses (e.g., Streptococcus pneumoniae) and also some gram-negative pathogens.   They are highly valuable drugs. Azithromycin in particular is valued because, unlike many other antibiotics, the usual course of treatment is only 5 days, which reinforces patient adherence to treatment and minimizes the development of resistance.   Patients are more likely to complete a shorter course