Comparison of Congenital Rubella Syndrome Cases at a Philippine Tertiary Hospital from 2009-2012 to 2019-2022.

Background and objective: The Philippines does not have a national congenital rubella syndrome (CRS) surveillance or registry. Regular monitoring of CRS cases in hospitals, including in a Philippine tertiary hospital, helped in the past to provide clinico-epidemiologic data on CRS. This study aimed to continue providing clinico-epidemiologic data on CRS cases seen in the Philippine tertiary hospital from 2009-2012 and 2019-2022 and compare the cases seen from said timelines.

Methods: A cross-sectional study was used, employing chart review of patients newly diagnosed with CRS from 2009-2012 and 2019-2022 in the Department of Ophthalmology and Visual Sciences at the Philippine tertiary hospital.

Results: Forty-two patients newly diagnosed with CRS from 2009-2012 and 2019-2022 were included. Only 14 (33%) were serologically-confirmed cases (albeit qualitatively). Median age (first and third interquartile ranges) at consult was 1 year (0.4, 2.5). Twenty-four (57%) patients had maternal history of rashes and/or fever. Trimester of pregnancy when mother became symptomatic was not significantly correlated with chief complaint (p=0.20) and numbers of ophthalmic (p=0.68) and systemic manifestations (p=0.32). Cataract was the most common ophthalmic manifestation present in 40 (95%) patients. Twenty-six (62%) patients had other associated systemic findings of which hearing loss was the most common. Only 29 of 40 patients with cataract underwent lensectomy, with 23 patients having poor visual prognosis prior to surgery (5 with nystagmus alone, 10 with nystagmus and strabismus, and 8 with strabismus alone).

Discussion: Using ophthalmic manifestations as primary indicator, this study provided an update on the CRS cases in the country. Laboratory confirmation remains a challenge in diagnosing CRS as the tests are costly and not widely available. There was increase from 2009-2012 compared to 2019-2022 in number of patients who underwent surgical treatment for cataract but visual outcomes were suboptimal due to delay in consultation. Although there was a decrease in number of CRS cases seen in the Philippine tertiary hospital, this cannot be attributed to increased rubella-containing vaccine (RCV) coverage alone.

Conclusion: Provision of data from individual hospital-based studies similar to this highlights the need for a national CRS surveillance system or registry. This can better gauge the burden of CRS and identify the gap in RCV coverage.