Ocular Manifestations of Scrub Typhus and Their Association with In-Hospital Mortality

Scrub typhus, caused by Orientia tsutsugamushi, is a major cause of acute febrile illness in Asia and is associated with significant morbidity and mortality. A prospective observational study (July 2021 to October 2022) was conducted at a tertiary referral center in Northern India to determine the incidence of ocular manifestations and their association with in-hospital mortality. Patients aged ≥12 years with laboratory-confirmed scrub typhus were enrolled. Ocular examinations were performed within 24 hours of admission by a trained emergency physician and independently validated by an ophthalmologist. Clinical, laboratory, and outcome data were collected, and patients with ocular findings were re-examined at 3 months. Multivariable logistic regression was used to assess factors associated with in-hospital mortality. Of 250 screened patients with acute febrile illness, 89 met the inclusion criteria for scrub typhus. The mean age was 35 years, and 54% were female. Ocular manifestations were identified in 24 patients (27%), most commonly retinal hemorrhages (25%) and optic disc edema (17%); bilateral involvement occurred in 54%. At 3-month follow-up, 58% of ocular abnormalities were resolved, whereas in-hospital mortality was 9% (8/89). Mortality was significantly higher among patients with ocular involvement (25% versus 3%; P = 0.004). In adjusted analysis, ocular manifestations were independently associated with in-hospital mortality (odds ratio: 9.07; 95% CI: 1.69-76.8; P = 0.018). Ocular involvement is common in scrub typhus and may serve as a simple, noninvasive marker of disease severity in resource-limited settings.