The Effect of Antihelminthic Treatment on Subjects with Asthma from an Endemic Area of Schistosomiasis: A Randomized, Double-Blinded, and Placebo-Controlled Trial

Abstract

This is a prospective, double-blinded, and placebo-controlled trial evaluating the influence of antihelminthic treatments on asthma severity in individuals living in an endemic area of schistosomiasis. Patients from group 1 received placebo of Albendazole or of Praziquantel and from group 2 received Albendazole and Praziquantel. Asthma severity was assessed by clinical scores and by pulmonary function test. There was no significant difference in the asthma scores from D0 to D1–D7 after Albendazole or Praziquantel and from D0 to D30–90 after Albendazole or Praziquantel in both, group 1 and 2. It was observed, however, a clinical worsening of the overall studied population after 6 months and 12 months of antihelminthic treatments. Additionally, we observed increased frequency of forced expiratory volume in 1 second (FEV1) <80% on 12 and 18 months after treatment. The worsening of asthma severity after repeated antihelminthic treatments is consistent with the hypothesis of the protective role conferred by helminths in atopic diseases.

Association between gastrointestinal tract infections and glycated hemoglobin in school children of poor neighborhoods in Port Elizabeth, South Africa

“…After deworming, which triggers several hyper-inflammatory processes and shifts immune responses from Th2 to Th1, groups of children treated with either albendazole or mebendazole (against soil-transmitted helminthiasis) or praziquantel (against schistosomiasis) had a higher positive response to the skin-prick test and allergy related symptoms [ 49 , 50 ]. Nevertheless, other studies emphasized that anthelmintic treatment did not have an effect on clinical eczema and asthmatic severity scores [ 51 , 52 ].…”

The Hygiene Hypothesis and Its Inconvenient Truths about Helminth Infections

“…Studies using anthelminthic treatment in patients with asthma have been met with conflicting results as well. A prospective study of albendazole or praziquantel in a schistosomiasis-endemic area of Brazil did not show any respiratory benefit in children with asthma but led to overall worsening of asthma severity after repeated anthelminthic administration [ 24 ]. Conversely, the use of anthelminthic therapy, albendazole, in a cohort of asthmatic patients in an Ascaris -endemic region of Venezuela resulted in reductions in inhaled maintenance and rescue therapy as well as a reduction in asthma exacerbations [ 25 ].…”

Association between allergic responses and Schistosoma mansoni infection in residents in a low-endemic setting in Brazil

“…For instance, IL-10 can inhibit the release of histamine and other mast cell mediators. Because infection with S. mansoni is associated with increased IL-10 production, this may be the main mechanism by which allergic response is suppressed in infected individuals 16 .…”