A ten-year report of microbial keratitis in pediatric population under five years in a tertiary eye center

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 in pediatric population aged less than two years: a tertiary eye institute experience

BACKGROUND

Infectious keratitis is a serious ocular condition, which can lead to corneal scarring, vision loss, and even blindness. Pediatric infectious keratitis accounts for about 13% of all cases, although there is a lack of comprehensive data regarding keratitis in less than two years of age population group. This study was aimed to determine predisposing factors, clinical characteristics, microbial profile, and management of infectious keratitis in a population of children aged less than two years.

MATERIALS AND METHODS

A retrospective study was carried out in a tertiary eye institute over a period of 18 years from July 2005 to December 2022. Collected data was analyzed for demographics, predisposing factors, clinical features, and treatment methods.

RESULTS

Fifty-seven cases of keratitis were identified. Age of the patients ranged from 1 to 24 months (Median: 6, interquartile range: 2-10). Thirty cases were male (52.6%). Predisposing factors were identified in 39 cases (68.4%): consisting of prior ocular trauma (n = 15), previous intraocular surgery (n = 11), ocular surface disease (n = 10), nasolacrimal duct obstruction (n = 4), prematurity (n = 3), developmental delay (n = 2), TORCH infection (n = 1), and contact lens (n = 1). Corneal thinning was observed in 29 eyes (50.9%), which progressed to perforation in 13 eyes (22.8%). Three patients developed endophthalmitis (95% CI, 1.5-13.4%). Most eyes had negative smear (60.4%) and culture (59.6%) results. Pseudomonas aeruginosa was the most common microorganism (11 of 21). Candida albicans was isolated in one case. In vitro susceptibility results showed good coverage of the combined ceftazidime and vancomycin regimen (100%). Surgical procedures were carried out in 35 eyes (61.4%) and 15 eyes required tectonic procedures (26.3%).

CONCLUSION

Despite good coverage of medical treatment over cultured isolates, surgical tectonic intervention was required in nearly a quarter of cases to resolve the corneal infection. This finding indicates the necessity of prompt patient referring, corneal sampling and initiation of the treatment.

Incidence and clinical characteristics of paediatric keratitis

BACKGROUND/AIMS

To report the incidence and clinical characteristics of paediatric keratitis diagnosed over a 10-year period in a well-defined population.

DESIGN

Retrospective, population-based study.

METHODS

Setting: multicentre.

POPULATION

patients (<19 years) diagnosed with keratitis as residents of Olmsted County from 1 January 2000, through 31 December 2009.

MAIN OUTCOME MEASURES

calculated annual age-specific and gender-specific incidence rates, demographic information and initial and final visual acuity.

RESULTS

A total of 294 diagnoses of keratitis occurred in 285 children during the 10-year period, yielding an incidence of 78.0 per 100 000 younger than 19 years (95% CI 69.0 to 87.1) or approximately 1 in 1282 children. The incidence increased throughout the 10-year study period (p<0.001). The mean age at diagnosis was 15.3 years (range, 0.2-18.9) and 172 (60.4%) were women. The observed forms included keratitis due to contact lens wear in 134 (45.6%), infectious keratitis in 72 (24.5%), keratitis not otherwise specified in 65 (22.1%) and keratitis sicca in 23 (7.8%). The visual acuity was reduced to ≤20/40 in 61 (21.4) of the 285 patients at the initial examination and in 24 (8.4%) at the final examination. Children with infectious keratitis had the poorest presenting vision and the best final vision, whereas the reverse was true for those with keratitis sicca.

CONCLUSIONS

Keratitis, regardless of aetiology, was observed in approximately 1 in 1300 children by 19 years of age in this population-based cohort. Nearly half were related to contact lens wear and a decrease in vision to ≤ 20/40 occurred in 1 in 12 patients.

Update on Pediatric Corneal Diseases and Keratoplasty

Managing pediatric corneal disorders is challenging as the prognosis of pediatric keratoplasty depends on several factors. Advancements in the genetic basis of congenital corneal diseases and investigations in congenital corneal conditions provide a better understanding of pediatric corneal conditions. Surgeons performing keratoplasty in children now have a choice of various techniques. Evolving surgical techniques of anterior lamellar and endothelial keratoplasties has expanded the management interventions in these pediatric corneal morbidity conditions; however, considerable concerns still exist in association with corneal transplantation in infants and children. Outcomes in pediatric keratoplasty depend upon the preoperative indications, the timing of surgical intervention, intraoperative and postoperative factors including the patient/care givers' compliance. Factors such as low scleral rigidity, higher rate of graft failure, need for frequent examinations under anesthesia, and difficulty in optimal visual acuity assessment still remain a considerable challenge in pediatric scenarios. In children, deprivation amblyopia as a result of the corneal opacification can adversely affect visual development, causing dense amblyopia. Outcomes to surgical interventions for management of corneal opacification in children is further compromised by the pre-existing amblyopia apart from the concerns of refractive outcome of the graft. Graft rejection, graft infection, amblyopia, and glaucoma continue to be serious concerns. In recent years both anterior and posterior lamellar keratoplasty techniques are being increasingly performed in pediatric eyes, which offer advantages in the form of lower risk of graft rejection. The timing of surgery, careful case selection, cautious intraoperative approach, and optimal postoperative management can improve the anatomical and functional outcome in difficult cases.

Spectrum of bacterial keratitis in North India: A retrospective analysis of six years at a tertiary care eye center

Purpose

To analyze the pattern of bacterial pathogens causing infective keratitis and their resistance to the recommended antibiotics over six years.

Methods

It was a retrospective study of 9,357 cases of bacterial keratitis from January 2015 to December 2020, at a tertiary care ophthalmic center. A total of 9,547 corneal specimens were obtained from the study subjects. Demographic details of the patients, pathogenic bacteria isolated, and their antimicrobial susceptibility were noted and analyzed.

Results

Bacterial pathogens were identified in 23.52% of the specimens. The most common isolates were coagulase-negative Staphylococci (60.75%), followed by Pseudomonas aeruginosa (14.23%), Staphylococcus aureus (13.92%), gram negative bacilli of the family Enterobacterales (8.64%), Streptococcus spp. (1.72%), Acinetobacter spp. (0.13%), and other non-fermenting gram-negative bacilli (0.57%). In Staphylococci, 55-80% of isolates were resistant to erythromycin, and 40-70% to fluoroquinolones, while no resistance was observed against vancomycin. 40-60% of isolates of P. aeruginosa were resistant to cephalosporins, 40-55% to fluoroquinolones, and 30-60% to aminoglycosides. Also, 40-80% of isolates of Enterobacterales were resistant to cephalosporins, and 50-60% to fluoroquinolones. Most gram-negative isolates were susceptible to carbapenems and polymyxin B.

Conclusion

To the best of our knowledge, our study is the largest compilation of microbiological profile of bacterial keratitis from North India. It highlights the current trend of the bacterial pathogens that cause infectious keratitis. Staphylococci and Pseudomonas were found to be the most common pathogens. Increased resistance was seen against some of the commonly prescribed empirical antibiotics. Such evidence is useful for restructuring the empirical prescription practices from time to time.

Cyclodextrins Allow the Combination of Incompatible Vancomycin and Ceftazidime into an Ophthalmic Formulation for the Treatment of Bacterial Keratitis

Ceftazidime (CZ) and vancomycin (VA) are two antibiotics used to treat bacterial keratitis. Due to their physical incompatibility (formation of a precipitate), it is not currently possible to associate both molecules in a single container for ophthalmic administration. We firstly characterized the incompatibility then investigated if 2-hydroxypropyl-beta (HPβCD) and 2-hydroxypropyl-gamma cyclodextrins (HPγCD) could prevent this incompatibility. The impact of pH on the precipitation phenomena was investigated by analysing the supernatant solution of the mixture using high performance liquid chromatography. A characterization of the inclusion of CZ with HPγCD using ¹H nuclear magnetic resonance (NMR), and VA with HPβCD using ¹H-NMR and a solubility diagram was performed. A design of experiment was built to determine the optimal conditions to obtain a formulation that had the lowest turbidity and particle count. Our results showed that VA and CZ form an equimolar precipitate below pH 7.3. The best formulation obtained underwent an in-vitro evaluation of its antibacterial activity. The impact of HPCDs on incompatibility has been demonstrated through the inclusion of antibiotics and especially VA. The formulation has been shown to be able to inhibit the incompatibility for pH higher than 7.3 and to possess unaltered antibacterial activity.