Contact lens-associated infectious keratitis: microbiological profile, management, and hygiene behaviors in a tertiary eye hospital

Int Ophthalmol. 2026 Jun 1;46(1):247. doi: 10.1007/s10792-026-04111-w.

Abstract

Purpose: To evaluate the microbial spectrum and management of contact lens-associated infectious keratitis (CL-AIK), with an emphasis on behavioral risk factors.

Methods: This retrospective study was conducted between 2021 and 2023 and involved seventy-four eyes of 70 consecutive diagnosed with CL-AIK at a tertiary care eye hospital. The hygiene practices, clinical and diagnostic findings, including corneal smear and culture, in vivo confocal microscopy (IVCM), and polymerase chain reaction (PCR), were analyzed. The associations between risk behaviors and clinical outcomes were examined.

Results: A total of 74 eyes from 70 patients (47 females, 63.5%; mean age: 31.24 ± 10.08 years) were reviewed for cases of CL-AIK. The initial best-corrected visual acuity (BCVA) was 1.28 ± 1.27 LogMAR. Diagnostic confirmation was obtained using multiple methods: chocolate agar culture (97.3% usage, 37 (51.4%) positivity), non-nutrient agar with Escherichia coli culture (79.7% usage, 7(11.86%) positivity), PCR testing (79.7% usage, 15 (25.4%) positivity), and IVCM (81.1% usage,18 (29.3%) positivity for Acanthamoeba spp.). Among the 70 patients, 24 (32.4%) rinsed their lenses with tap water, 22 (29.7%) wore lenses overnight, and 14 (18.9%) had exposed to water during showering or swimming. Exposure to water while wearing contact lenses was significantly more common in patients with fungal keratitis (3/4,75%, p = 0.002). The use of expired lenses (3/23, 13.04%; p = 0.008) and prolonged wear (> 12 h; 14/23, 60.8%; p = 0.04) were significantly higher in Acanthamoeba keratitis (AK).

Conclusion: Although many individuals reported good hygiene practices, high-risk behaviors such as swimming or showering while wearing contact lenses and prolonged daily use (> 12 h) remain important contributors to ocular complications. Prevention strategies should focus not only on general hygiene practices but also on addressing these high-risk behaviors. Additionally, the routine use of multimodal diagnostic techniques has dramatically improved the detection of atypical microorganisms, particularly Acanthamoeba spp.

Keywords: Acanthamoeba; Contact lens; Invivo confocal microscopy; Polymerase chain reaction; Pseudomonas aeruginosa.

MeSH terms

  • Acanthamoeba Keratitis
  • Adolescent
  • Adult
  • Bacteria / isolation & purification
  • Contact Lenses* / adverse effects
  • Contact Lenses* / microbiology
  • Cornea / microbiology
  • Eye Infections, Bacterial* / diagnosis
  • Eye Infections, Bacterial* / microbiology
  • Eye Infections, Bacterial* / therapy
  • Female
  • Humans
  • Hygiene*
  • Keratitis* / diagnosis
  • Keratitis* / microbiology
  • Keratitis* / therapy
  • Male
  • Microscopy, Confocal
  • Middle Aged
  • Polymerase Chain Reaction
  • Retrospective Studies
  • Risk Factors
  • Tertiary Care Centers / statistics & numerical data
  • Visual Acuity
  • Young Adult