Correlation of Clinical Severity of Trachomatous Inflammation and Chlamydia trachomatis Bacterial Load

The purpose of this study was to investigate the correlation between bacterial load of Chlamydia trachomatis as measured from quantitative polymerase chain reaction (qPCR) and the relative clinical severity of trachomatous inflammation. Individuals with trachoma from rural communities in Ethiopia had photographs taken as well as swabs obtained of the upper tarsal conjunctivas. Conjunctival swabs were processed with PCR assay, which provided quantitative results of ocular chlamydial load. A series of 125 conjunctival photographs were ranked from least to most severe according to clinical severity for follicular and papillary conjunctivitis. Higher intensity rankings of trachomatous inflammation were associated with higher chlamydial load for both follicular inflammation (Spearman's ρ = 0.43; P <0.001) and papillary inflammation (Spearman's ρ = 0.50; P <0.001). Rankings of trachomatous inflammation may be a clinically meaningful indicator of trachoma.