Procedures, Visits, and Procedure Costs in the Management of Microbial Keratitis

Infectious keratitis in Western New York: a 10-year review of patient demographics, clinical management, and treatment failure

Background

Infectious keratitis (IK) is a blinding disease and an important cause of ocular morbidity. Understanding regional trends in IK are important to understand the epidemiology and clinical outcomes of this disease.

Methods

In this 10-year retrospective review, patient characteristics including sociodemographic factors, medical history, and ocular history were collected as well as the clinical course and outcomes. This study particularly focused on these characteristics as it relates to treatment failure in IK, as defined as requiring more than 2 weeks to heal or surgical intervention, likelihood of having microbiology cultures collected, surgical intervention, and presenting disease severity.

Results

935 cases of IK were identified at the University of Rochester. Age (p=0.004), history of prior corneal transplant (p=0.009), severe vision loss on presentation (p<0.001), large ulcer size (p=0.001), and fungal (p=0.001) or protozoan (p=0.009) infections were all significantly associated with treatment failure. Both ulcer size (p<0.001) and severity of vision loss (p<0.001) were associated with a higher likelihood of having microbiology cultures as well as surgical intervention. Patients' whose home address was greater than 60 miles from the University were also more likely to present with a more severe ulcer (p<0.001) and undergo a surgical intervention (p=0.05). In studying the impact of race and ethnicity, Black patients were less likely to receive corneal cultures compared to White patients (p=0.02).

Conclusions

This study defined the patient characteristics and clinical course of patients with IK over 10 years at the University of Rochester providing insight into regional trends of the patient population as well as clinical outcomes.

Direct Cost Analysis of Microbial Keratitis in North China: A Hospital-Based Retrospective Study

Microbial keratitis (MK) is the fourth leading cause of blindness globally, imposing a substantial burden on the healthcare system. This study aims to determine the cost composition of MK patients and explore factors influencing these expenses. We analyzed the demographics, clinical features, and costs of 602 MK patients treated at Beijing Tongren Hospital from June 2021 to October 2023. The analysis revealed the average total cost of treating MK was USD 1646.8, with a median of USD 550.3 (IQR: 333.3-1239.1). Patients with Acanthamoeba keratitis (AK) incurred the highest median total costs at USD 706.2 (IQR: 399.2-3370.2). Additionally, AK patients faced the highest costs for ophthalmic exams and laboratory tests (both p < 0.001), while patients with fungal keratitis (FK) and viral keratitis (VK) experienced higher medication costs. Costs varied significantly with the severity of MK, especially for outpatients at severity level 4, which was markedly higher than levels 1-3 (USD 1520.1 vs. USD 401.0, p < 0.001). Delayed presentation also resulted in increased costs (USD 385.2 vs. USD 600.3, p < 0.001). Our study highlights the financial burden associated with MK treatment and underscores the importance of timely and accurate diagnosis and intervention.

Clinical characteristics, predisposing factors, and management of moraxella keratitis in a tertiary eye hospital

PURPOSE

The Moraxella species is a very uncommon pathogen that leads to microbial keratitis (MK). This study aimed to evaluate the clinical features, predisposing factors, and outcomes of Moraxella keratitis in patients of a tertiary eye hospital.

METHODS

This retrospective study was conducted from 2015 to 2022, on patients who were admitted with the diagnosis of Moraxella keratitis confirmed by positive culture in a referral eye hospital. Demographics, predisposing factors, best-corrected visual acuity (BCVA), and prognosis were assessed.

RESULTS

A total of 106 individuals diagnosed with Moraxella keratitis, were analyzed. The mean age was 54.42 ± 19.43 years. The mean baseline BCVA of the patients was 2.28 ± 0.6 LogMAR, while this amount reached 1.49 ± 0.81 in the 6-month follow-up (P-value = 0.02). The mean BCVA in the six-month follow-up of the patients who needed surgical interventions was significantly lower than the patients who received only medical treatment (2.15 ± 0.65 vs. 1.29 ± 0.75 LogMAR, P-value = 0.02). Patients with diabetes and those without diabetes did not substantially vary in the prevalence of corneal perforation (P-value = 0.515). Three predisposing factors including corneal perforation (odds ratio = 19.27, P-value = 0.001), hypertension (HTN) (odds ratio = 3.62, P-value = 0.03), and older age (odds ratio = 1.03, P-value = 0.008) were significantly associated with more need for surgical interventions.

CONCLUSION

In this cohort, poor prognosis necessitating surgical interventions in Moraxella keratitis was found to be associated with corneal perforation, HTN, and older age.

Infectious keratitis associated with contact lens wear: REGINFECOR multicenter study

This 32-centre multicentre study addresses the lack of knowledge about the prevalence and significance of microbial keratitis (MK) associated with contact lens (CL) wear in Spain. A total of 304 cases recruited from 32 hospitals were studied and showed that infectious keratitis associated with contact lens wear mainly affects young women during the summer months. In this study, soft lenses with monthly replacement and single solution cleaning were most commonly used, purchased and fitted in opticians' shops. Common risk factors were identified among users, such as topping off solutions, prolonging the life of lenses, and frequently sleeping, swimming and showering with lenses. Overnight lens wear was significantly associated with a higher incidence of corneal opacities, and the presence of Pseudomonas aeruginosa in bacterial cultures was associated with more severe sequelae and a greater need for corneal transplantation. Although most cases were benign, the time taken to heal was long, which poses a problem for working patients. This study provides valuable epidemiological, microbiological and risk factor information and estimates the incidence of CL related MK in Spain to be approximately 1 case per 30,000 inhabitants per year.

Microbial keratitis and its management at a rural centre: achieving success with limited resources

PURPOSE

Microbial keratitis is a sight-threatening condition with a higher incidence in agrarian populations. In countries with a high indigent population, due to financial and other constraints, patients prefer to seek therapy locally rather than travel to advanced centres. The aim of this study is to describe the epidemiology, clinical characteristics, and outcomes of 60 consecutive patients with microbial keratitis managed at a rural centre.

METHODS

Descriptive case series. All patients clinically diagnosed with infectious keratitis were included. Corneal scrapings were obtained and microbiological identification was done by Gram stain. Anti-microbial therapy was commenced based on smear findings and the patients were followed up till disease resolution.

RESULTS

Sixty eyes of 60 patients were diagnosed with microbial keratitis in the study period. The mean age was 47.43 ± 18.69 years. Male:female ratio was 47:53. Risk factors included ocular trauma in the majority of patients (46/60; 76.7%). Microorganisms were identified on 75.6% of smears, with fungal filaments (65.4%) being the most common. Ulcers were central in over half (32/60; 53.3%), and > 3 mm in diameter in over three-fourths (81.6%) of patients. Forty-four patients (73.3%) achieved treatment success whereas 16/60 (26.6%) required referral to our tertiary-eye care facility for management. The median time to resolution was 14 days (IQR 10-26 days).

CONCLUSION

Our series demonstrates the feasibility of microbiology-guided therapy in microbial keratitis by ophthalmologists at the secondary rural eye-care level. Two-thirds of the patients could be successfully managed at the rural centre and only severe cases needed a referral to tertiary centres.

Sociodemographic and Clinical Predictors of Prolonged Length of Corneal Ulcer Hospitalizations

Importance

The length of stay (LOS) of hospitalizations may be a useful indicator of the burden of disease of corneal ulcers. Identifying variables associated with longer LOS may help to enhance delivery of care for high-risk patients.

Objective

To investigate the sociodemographic, social, and clinical factors associated with LOS in hospitalizations for corneal ulcers in the US.

Design, Setting, and Participants

This was a retrospective cross-sectional study of adult patients (aged >18 years) admitted with a primary diagnosis of corneal ulcer between quarter 4 of 2015 through 2020 and conducted using data from the National Inpatient Sample (NIS). Patients were stratified into 2 even cohorts based on LOS: LOS of 4 days or less and LOS greater than 4 days. Individual-level sociodemographic, social risk factors, and medical comorbidities associated with longer LOS were examined by multivariable regression. Data were analyzed from October 2015 to December 2020.

Exposure

Potential sociodemographics or medical comorbidities at hospital admission.

Main Outcome and Measure

The primary outcome of interest was factors associated with extended length of stay. The hypothesis being tested was formulated during data collection.

Results

A total of 1187 patients (mean [SD] age, 53.5 [20.9] years; 602 female [50.7%]) were included for analysis. The cohort with LOS greater than 4 days had higher total charges than the cohort with LOS of 4 days or less (mean [SD] charges, $79 504 [$86 719] vs $26 474 [$20 743]; P < .001). Sociodemographic variables associated with LOS greater than 4 days were Black race (adjusted odds ratio [aOR], 1.41; 95% CI, 1.03-1.92; P = .03), Medicare insurance (aOR, 1.42; 95% CI, 1.09-1.85; P = .009), and housing insecurity (aOR, 1.99; 95% CI, 1.29-3.06; P = .002). Medical comorbidities associated with LOS greater than 4 days were alcohol use (aOR, 1.50; 95% CI, 1.00-2.26; P = .05), dementia (aOR, 2.35; 95% CI, 1.36-4.07; P = .002), complicated diabetes (aOR, 1.75; 95% CI, 1.21-2.53; P = .003), uncomplicated diabetes (aOR, 1.57; 95% CI, 1.02-2.42; P = .04), drug misuse (aOR, 1.66; 95% CI, 1.08-2.57; P = .02), and legal blindness (aOR, 3.42; 95% CI, 1.19-9.82; P = .02). Based on NIS national estimates, corneal ulcers were estimated to have a direct annual health care expenditure of $35 819 590 in the US.

Conclusion and Relevance

Corneal ulcer hospitalizations represent a significant burden of disease for patients and health care systems. This study highlights sociodemographic and clinical factors that may help clinicians identify high-risk patients vulnerable to complications and morbidity due to corneal ulcers.

Corneal Specialists' Confidence in Identifying Causal Organisms of Microbial Keratitis

PURPOSE

Microbial keratitis (MK) is a potentially blinding corneal disease caused by an array of microbial etiologies. However, the lack of early organism identification is a barrier to optimal care. We investigated clinician confidence in their diagnosis of organism type on initial presentation and the relationship between confidence and presenting features.

METHODS

This research presents secondary data analysis of 72 patients from the Automated Quantitative Ulcer Analysis (AQUA) study. Cornea specialists reported their confidence in organism identification. Presenting sample characteristics were recorded including patient demographics, health history, infection morphology, symptoms, and circumstances of infection. The association between confidence and presenting characteristics was investigated with 2-sample t-tests, Wilcoxon tests, and Chi-square or Fisher's exact tests.

RESULTS

Clinicians reported being "confident or very confident" in their diagnosis of the causal organism in MK infections for 39 patients (54%) and "not confident" for 33 patients (46%). Confidence was not significantly associated with patient demographics, morphologic features, or symptoms related to MK. MK cases where clinicians reported they were confident, versus not confident in their diagnosis, showed significantly smaller percentages of previous corneal disease (0% versus 15%, p = 0.017), were not seen by an outside provider first (69% versus 94%, p = 0.015), or had no prior labs drawn (8% versus 33%, p = 0.046), and a significantly larger percentage of cases wore contact lenses (54% versus 28%, p = 0.029).

CONCLUSION

In almost half of MK cases, cornea specialists reported lack of confidence in identifying the infection type. Confidence was related to ocular history and circumstances of infection but not by observable signs and symptoms or patient demographics. Tools are needed to assist clinicians with early diagnosis of MK infection type to expedite care and healing.

Social Risk Factor Associations With Presenting Visual Acuity in Patients With Microbial Keratitis

Importance

Neighborhood-level social risk factors may contribute to health disparities in microbial keratitis (MK) disease presentation. Understanding neighborhood-level factors may identify areas for revised health policies to address inequities that impact eye health.

Objective

To investigate if social risk factors were associated with presenting best-corrected visual acuity (BCVA) for patients with MK.

Design, Setting, and Participants

This was a cross-sectional study of patients with a diagnosis of MK. Patients presenting to the University of Michigan with a diagnosis of MK between August 1, 2012, and February 28, 2021, were included in the study. Patient data were obtained from the University of Michigan electronic health record.

Main Outcomes and Measures

Individual-level characteristics (age, self-reported sex, self-reported race and ethnicity), presenting log of the minimum angle of resolution (logMAR) BCVA, and neighborhood-level factors, including measures on deprivation, inequity, housing burden, and transportation at the census block group, were obtained. Univariate associations of presenting BCVA (< 20/40 vs ≥20/40) with individual-level characteristics were assessed with 2-sample t, Wilcoxon, and χ2 tests. Logistic regression was used to test associations of neighborhood-level characteristics with the probability of presenting BCVA worse than 20/40 after adjustment for patient demographics.

Results

A total of 2990 patients with MK were identified and included in the study. Patients had a mean (SD) age of 48.6 (21.3) years, and 1723 were female (57.6%). Patients self-identified with the following race and ethnicity categories: 132 Asian (4.5%), 228 Black (7.8%), 99 Hispanic (3.5%), 2763 non-Hispanic (96.5%), 2463 White (84.4%), and 95 other (3.3%; included any race not previously listed). Presenting BCVA had a median (IQR) value of 0.40 (0.10-1.48) logMAR units (Snellen equivalent, 20/50 [20/25-20/600]), and 1508 of 2798 patients (53.9%) presented with BCVA worse than 20/40. Patients presenting with logMAR BCVA less than 20/40 were older than those who presented with 20/40 or higher (mean difference, 14.7 years; 95% CI, 13.3-16.1; P < .001). Furthermore, a larger percentage of male vs female sex patients presented with logMAR BCVA less than 20/40 (difference, 5.2%; 95% CI, 1.5-8.9; P = .04), as well as Black race (difference, 25.7%; 95% CI, 15.0%-36.5%;P < .001) and White race (difference, 22.6%; 95% CI, 13.9%-31.3%; P < .001) vs Asian race, and non-Hispanic vs Hispanic ethnicity (difference, 14.6%; 95% CI, 4.5%-24.8%; P = .04). After adjusting for age, self-reported sex, and self-reported race and ethnicity, worse Area Deprivation Index (odds ratio [OR], 1.30 per 10-unit increase; 95% CI, 1.25-1.35; P < .001), increased segregation (OR, 1.44 per 0.1-unit increase in Theil H index; 95% CI, 1.30-1.61; P < .001), higher percentage of households with no car (OR, 1.25 per 1 percentage point increase; 95% CI, 1.12-1.40; P = .001), and lower average number of cars per household (OR, 1.56 per 1 less car; 95% CI, 1.21-2.02; P = .003) were associated with increased odds of presenting BCVA worse than 20/40.

Conclusion and Relevance

Findings of this cross-sectional study suggest that in a sample of patients with MK, patient characteristics and where they live were associated with disease severity at presentation. These findings may inform future research on social risk factors and patients with MK.

Spectrum and resistance in bacterial infections of the ocular surface in a German tertiary referral center 2009-2019

PURPOSE

Aim of this study was to evaluate the frequencies, trends, and antibiotic resistance of bacteria collected from ocular surface or contact lens material in a German tertiary referral center from 2009 to 2019.

METHODS

Microbiological data from 2009 to 2019 was analyzed. Culture-dependent microbial identification and analysis of antibiotic sensitivity was completed by the Institute of Microbiology. Statistical analysis of age- and sex-specific differences as well as changes in the microbial spectrum and resistance over the study period was performed with GraphPad Prism 9.0 applying nonparametric tests (level of significance: p ≦ 0.05).

RESULTS

A total of 6361 specimens were analyzed. Positivity rate was 18.6%. Sixty-three percent (n = 680) of the bacterial isolates were derived from ocular surface and 37% (n = 399) from contact lens material. The ratio of gram-negative bacteria was significantly higher in contact lens material. Multiresistant bacteria showed a significant increase with patient age (p < 0.0001). An overall increase in resistance to levofloxacin (p = 0.0239) was detected. Only 2.4% and 3.1% isolates were resistant to a combination of moxifloxacin and gentamicin, respectively, levofloxacin and gentamicin.

CONCLUSIONS

The reported bacterial spectrum is similar to comparable centers. Our data show that it should not be assumed that the newest classes of antibiotics have the best efficacy or lowest resistance levels. In suspected bacterial conjunctivitis, we propose using gentamicin as first-line therapy. In therapy refractive cases and in involvement of the cornea, we recommend a combination of gentamicin and ofloxacin or moxifloxacin. Overall, the evaluated organisms showed good sensitivity to the regularly used antibiotics.