Abstract
Purpose: :
The association of Leptospiral Lru A and B gene with uveitis was reported by demonstration of antibodies against the proteins coded by these genes in uveitic patients. The present study was done to detect these genes by the application of Polymerase chain reaction (PCR) in the aspirated anterior chamber (AC tap) fluids.
Methods: :
PCR primers targeting LruA and B gene of pathogenic strains of Leptospira interrogans were designed using primer premier software. The primers were tested for analystical specificty against DNA extracted from clinically important bacteria, fungi and viruses. The analytical sensitivity was estimated with 10 fold dilutions of DNA extracted from Leptospira interrogenas serovar australis obtained from Leptospira reference center (Tamil Nadu University of Veterinary and Animal Sciences, Madhavaram, Chennai, India). PCRs were applied onto 90 intraocular specimens collected from 90 patients with uveitis. Twenty intraocular specimens with proven infectious endophthalmitis by culture and 20 others from patients undergoing cataract surgery were included as controls.
Results: :
The primers were specific for Leptospira interrogans. Both the sets of primers were sensitive enough to detect a DNA concentration of 2 fg. Among the 90 specimens 20 (22.22%) showed the presence of either LruA or LruB genes of Leptospira interrogans. Among these, seventeen were positive for LruB gene and two were positive for LruA gene and one showed presence of both. Four among the twenty were also positive for HSV -1 DNA. While the controls remained negative. The PCR amplified products were further confirmed by PCR-DNA sequencing as Leptospira interrogans.The 20 patients in whom LruA or B gene was detected had a diagnosis of recurrent uveitis (6), Hypopyon pan uveitis (1), granulomatous anterior uveitis (3), Fuch's heterochromic cyclitis(1), Anterior uveitis(1), peripallilary GHPLC (1), subretinal abscesss (1), Macular GHPLC (1), Pan uveitis (2), viral retinitis(1), atytical retinochoroiditis (2),
Conclusions: :
The absence of LruA and B gene in control AC tap aspirates and their presence in AC tap specimens of uveitic patients further strengthens view on the association these genes with Leptospira uveitis and these PCR tests may be included as part of investigation of uveitis patients to detect association of leptospira infection.
Keywords: aqueous • inflammation • uveitis-clinical/animal model