Incidence and outcomes of microbial keratitis after cyclophotocoagulation to treat childhood refractory glaucoma

To report the incidence and outcomes of microbial keratitis (MK) following cyclophotocoagulation (CPC) for treatment of refractory childhood glaucoma (CG) at a single center over a period of 6 years. In this cohort study, the medical records of children with CG who underwent CPC and subsequently presented with MK from 2014 to 2020 were reviewed retrospectively. Data were collected on age, type of glaucoma, surgeries before MK, CPC parameters, interval between CPC and MK, presenting symptoms of MK, infiltrate location, bacterial isolates, MK treatment, and outcomes. Among the 312 children who underwent CPC during the study period, 37 eyes of 33 children had MK, with an incidence of 1.8% (95% CI, 0.3-3.2). The median interval between CPC and MK was 4 years (IQR, 2.7-7.4). CPC was repeated once in 20 eyes (54%) and twice in 4 (11%). In 20 eyes, there was no pain at MK onset. The primary isolates were Streptococcus pneumoniae (12/27 [22%]) and Staphylococcus epidermis (8/27 [30%]). MK resolved in 17 eyes (46%) after treatment; 8 eyes (22%) underwent evisceration or had phthisis, and keratoplasty failed in 6 eyes (16%). The absence of pain at presentation with MK was negatively associated with resolution (OR = 5.0 [95% CI, 1.1-23.8]; P = 0.04). The absence of pain at MK onset may be a proxy for neurotrophic keratitis after CPC and is linked to poor response to management.