Document resource
Background Postoperative microbial keratitis (MK) can cause graft failure and vision loss following keratoplasty for corneal endothelial decompensation. Many previous studies found penetrating keratoplasty (PK) to result in a higher incidence of MK than Descemet’s membrane endothelial keratoplasty (DMEK) or Descemet’s stripping automated endothelial keratoplasty (DSAEK); however, findings vary. Recently, there has been a shift towards selective transplant procedures, with DMEK becoming mainstream over PK for endothelial decompensation globally around 2017. This systematic review therefore aims to determine the incidence of MK following DMEK, DSAEK and PK for endothelial decompensation from 2017 to 2025 and to assess variation by follow-up duration, socioeconomic status, microbe type, patient age, contact lens wear and time after surgery.Methods Multiple databases were systematically searched during 2017–2025. The Newcastle-Ottawa scale evaluated bias. Random-effects meta-analyses with logit transformation were performed; heterogeneity was assessed using the I 2 statistic. Sensitivity analyses confirmed robustness.Results Pooled MK incidence was highest following PK (4.84%; 95% CI 3.25% to 7.15%; I 2=97.7%), followed by DMEK (0.71%; 95% CI 0.18% to 2.86%; I2=83.5%), then DSAEK (0.27%; 95% CI 0.19% to 0.38%; I2=0%). Subgroup analyses showed variation but few significant differences. Trends suggested significantly higher MK incidence following PK in studies with longer follow-up. Bacterial keratitis was the most common overall; however, DMEK showed a more even distribution across microbe types.Conclusion MK incidence was highest following PK. High heterogeneity and limited DMEK/DSAEK data warrant cautious interpretation.PROSPERO registration number CRD420251179122.