Incidence and Clinical Characteristics of Infantile Conjunctivitis in a Western Population.

OBJECTIVE

To describe the incidence and clinical characteristics of conjunctivitis in the first year of life.

DESIGN

Population-based cohort study.

PARTICIPANTS

All infant (≤12 months of age) residents of Olmsted County, Minnesota, diagnosed with conjunctivitis from January 1, 2005, through December 31, 2014.

METHODS

The medical records of all potential cases identified by the Rochester Epidemiology Project database were reviewed.

MAIN OUTCOME MEASURES: Incidence rate and clinical features of infantile conjunctivitis.

RESULTS

A total of 2175 infants were diagnosed during the 10-year period, yielding an incidence of 10,422 per 100,000 children or approximately 1 in 10 infants by 1 year of age. The mean age at diagnosis was 4.9 months (range, 1 day-12 months), and 1001 (46.0%) were female. Both eyes were involved in 1180 (54.3%), the right eye alone in 506 (23.3%), and 489 (22.5%) in the left. Five hundred seventy-six (26.5%) of the 2175 were diagnosed at ≤30 days of life, from which topical cultures were obtained in 111 (19.7%). Only 36 (32.4%) of the cultures showed bacterial agents, with Chlamydia present in 3. Treatment for infantile conjunctivitis, where recorded, included topical antibiotics in 523 (90.8%) and simple observation in 47 (8.2%).

CONCLUSIONS

Conjunctivitis in the first year of life occurred in approximately 10% of infants in this population-based cohort. More than half involved both eyes, one-quarter were identified in the first 30 days of life, and sight-threatening infectious agents were rare.