Toxocariasis associated with chronic cough in childhood: a longitudinal study in Hungary

Abstract

Chronic cough lasting 8 weeks or more often seems to be an intractable problem in childhood. Toxocara infection is associated with an increased prevalence of airway symptoms and may be the possible aetiological agent of chronic cough. Of 425 children aged 2-17 years with chronic cough who were investigated for toxocariasis and the distribution of bronchial asthma (BA), cough variant asthma (CVA) and non-asthmatic eosinophilic bronchitis (NAEB), 136 (32%) were seropositive for Toxocara canis antigens. Ninety-three of the 136 were adequately assessed, diagnosed and followed up during 1 year. BA was diagnosed in 40%, CVA in 27% and NAEB in 33% of the children. The eosinophil cell count, serum T. canis IgG levels and symptoms are predictors of the improvement or the decline of the condition. Presuming the aetiopathogenetic role of T. canis in the inflammatory process of chronic cough, we treated the children not only with inhaled corticosteroid (ICS), but also with a 1-week course of anthelminthics. We could significantly decrease the dose of ICS in 23 (62%) of the 37 with BA. The administration of anthelminthics and the avoidance of sensitizers were sufficient for those with NAEB; none needed ICS. ICS therapy could be stopped 2-3 months later in 17 (68%) of the 25 with CVA. We found that 8 of the 25 with CVA (32%) presented asthmatic symptoms at the end of the 1-year period. In Hungary, T. canis may be a potential sensitizer for chronic cough in seropositive children. Deworming therapy will then alleviate the airway symptoms without exacerbation in patients with BA, and have a positive effect on those with NAEB and the majority of those with CVA.

Cerebral Toxocariasis: Silent Progression to Neurodegenerative Disorders?

“…Infected children may present with a persistent cough which can be treated with anthelminthics (88). However, most pathology associated with VLM occurs in the liver.…”

Analysis of serum cytokine levels in children with chronic cough associated with Toxocara canis infection

“…In contrast with the helminth burden in endemic areas, the occurrence of toxocariasis in Hungary is mild and/or sporadic . The majority of our patients with chronic cough came from rural areas.…”

“…The prevalence of toxocariasis in children living in urban areas is estimated to be 10·2% , whereas in developing countries, the seroprevalence is 86% among children living in poor circumstances . An earlier estimate of the seroprevalence for Toxocara in healthy Hungarian children was 17%, as compared with 32% in children with chronic cough .…”

Toxocariasis: Visceral and Ocular Larva Migrans

“…However, other studies failed to demonstrate an association between Toxocara seropositivity and asthma; one study suggested that this association may be attributed to cross-reactivity. There was also some evidence that treatment of chronic cough with both asthma therapy and anthelminthic may be beneficial (Bede et al, 2008).…”