[Effect of mustard gas exposure on lid margin flora in chronic blepharitis: a case control study]

ABSTRACT

To evaluate the microbiological characteristics of lid margin flora in chronic blepharitis in individuals exposed to mustard gas in comparison to nonexposed patients. In this case-control study, among 289 patients with documented ocular manifestations of mustard gas, 150 patients with clinical sings of blepharitis served as the case group. Microbiologic evaluation was conducted in these patients and compared to that of 100 unexposed patients with chronic blepharitis. In 150 patients with mustard gas exposure and chronic blepharitis, staphylococcus epidermidis [78%] and staphylococcus aureus [57%] were significantly higher than control group [P< 0.01]. Moreover, staphylococcus aureus had more resistance to common antibiotics in the case group. Fungi were isolated more frequently in cases compared with controls [30% vs. 4%, P<0.01]. Cladosporium and Candida were the most common species. Microbiological evaluation in patients with chronic blepharitis associated with mustard gas is significantly different from other patients. Staphylococcus spp, including strains resistant to Methicillin, and fungi were more frequently isolated in exposed patients. The relationship between microbial culture and the severity of ocular manifestations in mustard gas exposed cases warrants further investigation