ENDOGENOUS ENDOPHTHALMITIS ASSOCIATED WITH INJECTION DRUG USE COMPARED WITH OTHER ETIOLOGIES

To compare features of endogenous endophthalmitis associated with injection drug use (IDU) to endogenous endophthalmitis from other etiologies.

The authors retrospectively collected data on patients with endogenous endophthalmitis due to IDU or other causes from three academic tertiary care centers over a six-year period. Differences in presenting characteristics, culture results, treatment, and visual acuity were compared between groups.

Thirty-eight patients (34%) had IDU-associated endogenous endophthalmitis while 75 patients (67%) had endogenous endophthalmitis from other causes. Compared with patients in the non-IDU group, IDU patients were significantly younger, more frequently male, had longer duration of symptoms at diagnosis, and were less likely to have bilateral disease ( P < 0.05 for all). Injection drug use patients were less likely to have a systemic infection source identified (29% vs. 71%, P < 0.001) or have positive cultures (47% vs. 80%, P < 0.001). The IDU group was less likely to be admitted to the hospital (71% vs. 92%, P = 0.005) and less likely to receive treatment with intravenous antimicrobials (55% vs. 83%, P = 0.003). Visual acuity did not significantly differ between groups.

Endophthalmitis related to IDU presents in younger patients with less comorbidities and frequently without positive cultures or an identifiable systemic source; therefore, a high index of suspicion is needed to identify this disease.