The role of IgG and its subclasses in byssinosis.

Abstract

A case control study was performed in 6 cotton mills in KwaZulu-Natal, South Africa. The study used questionnaire and pulmonary function testing results to categorise respiratory symptoms in 52 exposed symptomatic, 30 exposed asymptomatic and 46 unexposed control subjects. These categorisation results were used to explore the relationship between serum IgG subclasses and cotton-specific IgG to byssinosis. No definitive relationships between the serum IgG subclasses and clinical and functional symptoms of byssinosis were found . Whereas, exposed symptomatic (22.72 mg All) subjects had significantly higher (P = 0.01) mean specific IgG concentrations than exposed asymptomatic (15.02 mg All) or unexposed control (13.08 mg All) subjects. A pathoaetiological or marker-aetiological role is indicated for specific IgG in the development of byssinosis. The findings of this research challenged the status quo in terms of the accepted aetiological pathways of byssinosis. In turn the acceptance of a different aetiological pathway provided a possible answer to the varying presentation of the disease and by implication contested the current definition of byssinosis.