Incidence Of Infectious Keratitis Research Articles

Infectious keratitis after photorefractive keratectomy, femtosecond-LASIK and lenticule extraction in a 100,000-eye case series

This study evaluates the incidence and outcome of infectious keratitis after laser vision correction by photorefractive keratectomy (PRK), femtosecond LASIK, and keratorefractive lenticule extraction (KLEx) in a retrospective, consecutive, single-institute series. Patients with presumed infectious keratitis between 2011 and 2023 were analyzed. In PRK, manual deepithelialization was done, and mitomycin C was used with spherical equivalents greater than 3 diopters. Femtosecond LASIK and KLEx were performed with an LDV Ziemer laser; the interface was rinsed in both techniques. All treatments received post-operative netilmicin eyedrops. Finally, 106269 eyes of 54278 patients were included; 6 eyes of 6 patients were identified as having infectious keratitis (3 by staphylococci, 3 culture-negative). The overall incidence of infectious keratitis was 0.0056% (0.0164% after PRK, 0.0023% after femtosecond LASIK, 0.1366% after KLEx; Chi2 p<0.00001). The odds ratio for PRK compared to LASIK was 7.2 (p=0.0307); for KLEx compared to LASIK 59.7 (p=0.0008). Presentation after KLEx (2 days) was earlier than after PRK (5, 4, and 5 days) and LASIK (6 and 4 days). In all cases, hourly fortified cefazolin and tobramycin eyedrops were used, with a good response: 3 eyes maintained a 20/20 uncorrected visual acuity; 2 eyes 20/20 with myopic astigmatism; 1 eye ended 20/25 with correction because of irregular astigmatism. In conclusion, infectious keratitis was a rare complication, more common after KLEx and less common after femtosecond-LASIK. Only 3/6 cases had a positive culture. All the cases in our series had a favorable outcome.

Comparison of the efficacy and safety of removing bandage contact lenses on the fourth and seventh postoperative day after transepithelial photorefractive keratectomy

PurposeTo compare the differences in the removal of bandage contact lenses (BCLs) at 4 and 7 days after transepithelial photorefractive keratectomy (TransPRK) in term of visual rehabilitation, eye discomfort, and postoperative complications. MethodsThis retrospective cohort study included patients with myopia undergoing TransPRK; in Group 1, the BCLs were removed on the 4th postoperative day, while in Group 2, the BCLs were removed on the 7th postoperative day. All patients underwent a 6-month follow-up, including slit-lamp examination and visual acuity assessment. Subjective evaluations of pain and eye discomfort were recorded after the BCLs removal. ResultsIn total, 376 eyes of 191 patients in Group 1 and 346 eyes of 177 patients in Group 2 were enrolled. The two groups were matched for sex, age, preoperative corrected distance visual acuity, and tear film break-up time. Patients in Group 1 exhibited slightly lower levels of myopia, resulting in a shallower ablation depth and shorter ablation time than those in Group 2. No statistically significant differences in visual acuity recovery, haze severity, and incidence of infectious keratitis were observed within 6 months after surgery between the two groups. However, patients in Group 2 experienced significantly fewer discomfort symptoms (discharge, foreign body sensation, and blurred vision) after BCLs removal than patients in Group 1 and had fewer postoperative complications (recurrent corneal epithelial erosion). ConclusionDelayed removal of the BCLs one week after TransPRK effectively alleviated early discomfort symptoms and reduced the risk of recurrent corneal epithelial erosion without increasing the likelihood of infectious keratitis.

A Case Series of Infectious Keratitis After Corneal Cross-linking.

To present the 7-year experience of a tertiary eye hospital while exploring possible risk factors and incidence of infectious keratitis in patients undergoing standard corneal cross-linking (CXL). This retrospective cohort study included patients with progressive keratoconus undergoing standard CXL in the Farabi Eye Hospital and all other patients who had undergone CXL in other facilities and were diagnosed as having infectious keratitis in the 7-year period of the study. Among the total of 4,863 eyes that underwent CXL, 6 eyes developed infectious keratitis, yielding an incidence rate of 0.12%. Additionally, 13 eyes from 10 patients with a CXL history in other facilities who developed infectious keratitis were included. The mean age was 23.75 years, and 75% of patients were men and 25% were women. Gram-positive bacteria and Staphylococcus aureus were the most prevalent pathogens. Meibomian gland dysfunction, dry eye disease, or blepharitis were present in 12 patients. Medical treatment did not arrest the disease progress in 5 patients, which eventually required cases to undergo keratoplasty. This study supports the need for proper patient selection by using a comprehensive medical history. It also highlights the imperative role of rigorous patient education and follow-up, particularly in the first postoperative week. Finally, the study emphasizes aggressive early therapy for patients with suspicious findings. [J Refract Surg. 2023;39(8):564-572.].

The Nasopharyngeal Carcinoma and Its Effect on the Infectious Eye Disease: A Nationwide Cohort Study.

The purpose of this study is to investigate the potential correlation between nasopharyngeal carcinoma (NPC) and both infectious keratitis and orbital cellulitis. The retrospective cohort study used the National Health Insurance Research Database (NHIRD) as a data source. A total number of 4184 patients with NPC diagnosis were selected and matched to 16,736 non-NPC patients via the propensity-score matching (PSM). The main outcomes are the development of infectious keratitis and orbital cellulitis according to diagnostic codes and related medications. The Cox proportional hazard regression was adopted to estimate the adjusted hazard ratio (aHR) and 95% confidence interval (CI) of outcomes between the two groups. A total of 35 and 19 episodes of orbital cellulitis occurred in the NPC and non-NPC groups and the aHR was significantly higher in the NPC group (aHR: 1.34, 95% CI: 1.23−1.46, p = 0.0024). There were 2185 and 659 events of infectious keratitis in the NPC and non-NPC groups, and the NPC group revealed a significantly higher aHR than non-NPC group (aHR: 1.34, 95% CI: 1.23−1.46, p < 0.0001). Besides, the cumulative probability of infectious keratitis was significantly higher in the NPC group than the non-NPC group (p < 0.0001). The other risk factors of infectious keratitis include age from 20 to 30 years old, allergic respiratory diseases, allergic dermatological diseases, and external eye diseases (all p < 0.0001). In subgroup analyses, both the incidences of infectious keratitis (aHR: 1.33, 95% CI: 1.21−1.47) and orbital cellulitis (aHR: 2.36, 95% CI: 1.27−4.39) were significantly higher than the non-NPC group. The incidence of infectious keratitis was significantly higher in NPC patients without radiotherapy (aHR: 1.40, 95% CI: 1.26−1.55) compared to non-NPC population, while the rate of orbital cellulitis was similar between the NPC patients without radiotherapy (aHR: 0.76, 95% CI: 0.27−2.14) and non-NPC population. In conclusion, the existence of NPC associates with higher incidence of infectious keratitis which increases with NPC period, and the radiotherapy may be account for the higher rate of orbital cellulitis in NPC population.

Seasonal patterns of incidence, demographic factors and microbiological profiles of infectious keratitis: the Nottingham Infectious Keratitis Study.

The purpose of this study is to examine the seasonal patterns of incidence, demographic factors and microbiological profiles of infectious keratitis (IK) in Nottingham, UK. A retrospective study of all patients who were diagnosed with IK and underwent corneal scraping during 2008-2019 at a UK tertiary referral centre. Seasonal patterns of incidence (in per 100,000 population-year), demographic factors, culture positivity rate and microbiological profiles of IK were analysed. A total of 1272 IK cases were included. The overall incidence of IK was highest during summer (37.7, 95% confidence interval (CI): 31.3-44.1), followed by autumn (36.7, 95% CI: 31.0-42.4), winter (36.4, 95% CI: 32.1-40.8) and spring (30.6, 95% CI: 26.8-34.3), though not statistically significant (p = 0.14). The incidence of IK during summer increased significantly over the 12 years of study (r = 0.58, p = 0.049), but the incidence of IK in other seasons remained relatively stable throughout the study period. Significant seasonal variations were observed in patients' age (younger age in summer) and causative organisms, including Pseudomonas aeruginosa (32.9% in summer vs. 14.8% in winter; p < 0.001) and gram-positive bacilli (16.1% in summer vs. 4.7% in winter; p = 0.014). The incidence of IK in Nottingham was similar among four seasons. No temporal trend in the annual incidence of IK was observed, as reported previously, but there was a significant yearly increase in the incidence of IK during summer in Nottingham over the past decade. The association of younger age, P. aeruginosa and gram-positive bacilli infection with summer was likely attributed to contact lens wear, increased outdoor/water activity and warmer temperature conducive for microbial growth.

Infectious keratitis after laser vision correction: Incidence and risk factors

To describe the incidence and risk factors associated with microbial keratitis in a large population of laser vision correction (LVC) patients. Optical Express centers, Glasgow, United Kingdom. Retrospective case series. Records were searched to identify all cases of presumed microbial keratitis after LVC between January 1, 2008, and April 1, 2015. Consecutive patients having primary or enhancement LVC during that time served as controls. Data on preoperative age, sex, refraction, procedure, and surgery specifics were collected. A multivariate Cox proportional hazards model was used, and hazard ratios were calculated. Definite or probable microbial keratitis occurred in 26 of 564 165 eyes after laser in situ keratomileusis (LASIK) and in 11 of 81 792 eyes after photorefractive keratectomy (PRK) during the study period, for an overall incidence of 0.0046% (1 case per 21 697 procedures) after LASIK and 0.0013% (1 case per 7434 procedures) after PRK. A multivariate analysis found that those having PRK had a significantly higher incidence of microbial keratitis than those having LASIK (hazard ratio, 2.92; 95% confidence interval, 1.42-6.00; P=.004). No other analyzed factors were significant. Although the incidence of infectious keratitis was higher after PRK, the overall risk after any LVC procedure was very low.

Incidence of Infectious Corneal Ulcers, Portsmouth Study, UK

Aim: To identify the incidence of infectious keratitis in a population based in southern England.Methods: A retrospective review between January 1997 and December 2003 and a prospective study between January and December 2006 were undertaken at the eye casualty department of Queen Alexandra Hospital (QAH), Portsmouth, UK to identify the incidence of infectious keratitis.Results: QAH is a tertiary teaching hospital that serves Portsmouth and the catchment area of the county of Hampshire with an average population of 489,391 in the 7 year period of the retrospective study and 499100 in the one year prospective study. Infectious keratitis occurred in 1,786 patients in the retrospective study with an average of 255 patients per year and in 201 patients in the one year prospective study. The annual incidence of infectious keratitis was 52.1 and 40.3 per 100,000 persons in the retrospective and prospective studies respectively. The rate of bacterial and viral ulcers was lower in the prospective study than the average of either ulcer type in the retrospective study. A significant trend over time was found in the retrospective study that was mainly made by bacterial rather than viral ulcers. The rate of viral ulcers showed initial steady increase between 1997 and 2000 followed by continuous decline over the next three years of the retrospective study and maintained in the prospective study.Conclusions: Despite widely accepted views of the predominance of viral keratitis in the developed countries, these are decreasing in the population studied and contact lens-related bacterial corneal ulcers are more frequent than viral ulcers.

Infectious keratitis in 18 651 laser surface ablation procedures

To evaluate the incidence, culture results, risk factors, treatment strategies, and visual outcomes of infectious keratitis after surface ablation. Multicenter study in Spain. Case series. The medical records of patients who had surface ablation between January 2003 and December 2009 were reviewed to identify cases of infectious keratitis. The incidence, risk factors, clinical course, days to diagnosis, medical and surgical treatment, and visual outcome were recorded. Main outcome measures were incidence of infectious keratitis after surface ablation, culture results, response to treatment, and visual outcomes. The study reviewed the records of 9794 patients (18,651 eyes). Infectious keratitis after surface ablation was diagnosed in 39 eyes of 38 patients. The onset of infection was early (within 7 days after surgery) in 28 cases (71.79%). Cultures were positive in 13 of 27 cases in which samples were taken. The most frequently isolated microorganism was Staphylococcus species (9 cases). The final corrected distance visual acuity (CDVA) was 20/20 or better in 23 cases (58.97%), 20/40 or better in 36 cases (92.30%), and worse than 20/40 in 3 cases (7.69%). The incidence of infectious keratitis after surface ablation was 0.20%. Infectious keratitis is a potentially vision-threatening complication. Prompt and aggressive management with an intensive regimen of fortified antibiotic agents is strongly recommended. Proper management can preserve useful vision in most cases. No author has a financial or proprietary interest in any material or method mentioned.

Microbial keratitis following lamellar keratoplasty.

To determine the predisposing factors, etiologic agents, and clinical and visual outcomes in infectious keratitis following lamellar keratoplasty (LK). One hundred thirty-five eyes (135 patients) that had undergone LK were retrospectively analyzed for the occurrence of infectious keratitis following LK. The parameters evaluated were predisposing factors, seasonal variation, indications and type of LK, time interval between LK and infection, site and depth of infection, etiologic organisms, type of treatment, outcome in terms of graft status, secondary surgery, visual acuity, and the donor tissue profile. The incidence of infectious keratitis following LK was 11.11%. The most significant predisposing factor was persistent epithelial defect (3 eyes) and suture abscesses (3 eyes). Most cases occurred between May and August (9/15). Twelve cases developed infection within 2 weeks of surgery (80%). Seven cases (7/15) occurred with onlay grafts, 6 with inlay grafts, and 2 with large-diameter LK. Cultures of corneal scrapings were positive in 11 eyes (73.3%), and the most common isolated organism was coagulase-negative Staphylococcus (CNS). Only 2 eyes responded to medical therapy, and graft sloughing occurred in 9 cases. Six eyes underwent penetrating keratoplasty to either salvage the integrity of globe or for visual rehabilitation of cases where infection resulted in corneal opacity. Infections after LK may not be amenable to antimicrobial therapy and may necessitate the removal of the graft or a therapeutic penetrating keratoplasty.