Non-viral microbial keratitis in children

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.

Pediatric Non-Viral Microbial Keratitis: Predisposing Factors, Microbiological Profile, Treatment Modalities, and Visual Outcome

Purpose

To describe the predisposing factors, causative organisms, treatment modalities, and visual outcomes of childhood non-viral microbial keratitis in our region.

Patients and Methods

All cases with the clinical or microbiological diagnosis of non-viral microbial keratitis in patients ≤18 years presenting to Dhahran Eye specialist Hospital, a tertiary eye care hospital in Dhahran, Eastern Province, Saudi Arabia, between 2010 and 2020 were included. A retrospective chart review was conducted. Demographic data, predisposing factors, clinical characteristics, isolated microorganisms, and visual outcomes were recorded.

Results

Fifty-nine patients were included in this study, of which three cases were bilateral. The mean age was 9.3 ± 6.3 years (range: 14 days - 18 years). Predisposing factors were identified in 89.8% (n=53) of cases. Contact lens wear was the leading cause 35.6% (n=21), followed by trauma 27.1% (n=16), ocular diseases 11.9% (n=7), systemic diseases 10.2% (n=6), and ocular surgery 5.1% (n=3). Out of all cases, 66.1% (n=39) have undergone corneal scraping, out of which 43.6% (n=17) showed positive growth. Gram-negative organisms accounted for 47.1% (n=8) isolates of all culture-positive cases. Pseudomonas aeruginosa was the most common pure isolate, which accounted for 41.2% (n=7) of culture-positive cases, followed by Staphylococcus aureus 11.8% (n=2). The most common complication was corneal scar in 71.2% (n=42). Nineteen (32.2%) patients had poor outcome. Seven patients (11.9%) required further intervention, these included penetrating keratoplasty (n=1), deep lamellar keratoplasty (n=3), Photorefractive keratectomy (n=2), and Phototherapeutic keratectomy (n=1).

Conclusion

Childhood non-viral microbial keratitis is uncommon; however, it carries significant risks. Most cases were associated with preventable risk factors, with contact lens wear being the leading cause. Early detection and management are mandatory to reduce the risk of vision-threatening complications. The difficulty in assessment should not jeopardize proper evaluation and management of suspected cases.

A global perspective of pediatric non-viral keratitis: literature review

PURPOSE

This focused review aims to explore pediatric non-viral keratitis and to compare associated risk factors, etiologies, antibiotic susceptibilities, empiric treatments and outcomes.

METHODS

The authors performed a literature research for articles, published on PubMed, Google Scholar, Scopus and Embase online library, relevant to pediatric keratitis etiology, risk factors, antibiotic susceptibilities, treatment and outcomes. From the bibliography of selected articles, additional relevant articles were also considered. Of 34 articles identified, 21 were suitable for the purpose of this review.

RESULTS

Several risk factors are noted in the field of pediatric keratitis. Trauma is the most common in developing countries, while contact lenses wear is seen in developed economies. Previous ocular conditions and systemic diseases also contribute. Associated malnourishment and vitamin A deficit are fraught with a catastrophic prognosis. Among causative organisms, bacteria are more common than fungi and protozoa. Gram-positive organisms are predominant where contact lenses use is infrequent. Pseudomonas aeruginosa is often the leading pathogen in developed countries and is strongly associated with contact lens wear or malnourishment. Fungi are common in the tropics and associated with trauma. Levofloxacin seems the more effective empirical treatment when bacteria are suspected, but there is no agreement on a standard of care.

CONCLUSION

There are differences in etiologic patterns between developing and developed countries and different regions globally. Risk factors follow the same trend; however, there is no standard regimen being followed for empirical treatment of pediatric infectious keratitis. Associated malnourishment and vitamin A deficiency result in poorer outcomes.

Use of topical ocular antibiotics in young children: a Scandinavian drug utilization study

PURPOSE

Acute infectious conjunctivitis is a common disease. While usually self-limiting, children often receive treatment to be accepted back into nursery, day care or school. We aimed to describe trends in the utilization of topical ocular antibiotics in young children aged 0-4 years in Denmark, Norway and Sweden.

METHODS

Using individual-level data from the Danish National Prescription Registry (2000-2015), we provided detailed descriptions of treatment patterns at the individual level, stratified by age (0-1 years, 2-4 years) and antibiotic substance. Aggregate-level data for Danish, Norwegian and Swedish children (0-4 years) were obtained from publicly available data sources (2000-2016).

RESULTS

We identified 107 581 Danish children aged 0-4 years receiving 271 980 treatment episodes. The incidence rate was relatively stable between 2000 and 2010 (on average, 637 and 283/1000 person-years for 0- to 1- and 2- to 4-year-olds, respectively), after which it dropped by 37% until 2015. In the aggregated data, a markedly higher use was seen in Denmark (211/1000 children in 2016) compared with Sweden (42) and Norway (151). The decrease from 2010 onwards was observed in all three countries. Chloramphenicol and fusidic acid were the most commonly used topical ocular antibiotics across Scandinavia. Tobramycin was rarely used in Norway and Sweden (≤1/1000 children in 2016) compared with Denmark (24/1000 children).

CONCLUSION

Considerable variation is seen in the utilization of topical ocular antibiotics among children in Scandinavia, with Denmark having the highest use. Across the Scandinavian countries, however, a decline was noted from 2010 onwards.

Effect of acacia honey on cultured rabbit corneal keratocytes

BACKGROUND

Acacia honey is a natural product which has proven to have therapeutic effects on skin wound healing, but its potential healing effects in corneal wound healing have not been studied. This study aimed to explore the effects of Acacia honey (AH) on corneal keratocytes morphology, proliferative capacity, cell cycle, gene and protein analyses. Keratocytes from the corneal stroma of six New Zealand white rabbits were isolated and cultured until passage 1. The optimal dose of AH in the basal medium (FD) and medium containing serum (FDS) for keratocytes proliferation was identified using MTT assay. The morphological changes, gene and protein expressions of aldehyde dehydrogenase (ALDH), marker for quiescent keratocytes and vimentin, marker for fibroblasts were detected using q-RTPCR and immunocytochemistry respectively. Flowcytometry was performed to evaluate the cell cycle analysis of corneal keratocytes.

RESULTS

Cultured keratocytes supplemented with AH showed no morphological changes compared to control. Keratocytes cultured in FD and FDS media supplemented with 0.025% AH showed optimal proliferative potential compared with FD and FDS media, respectively. Gene expressions of ADLH and vimentin were increased in keratocytes cultured with AH enriched media. All proteins were expressed in keratocytes cultured in all media in accordance to the gene expression findings. No chromosomal changes were detected in keratocytes in AH enriched media.

CONCLUSION

Corneal keratocytes cultured in media supplemented with 0.025% AH showed an increase in proliferative capacity while retaining their morphology, gene and protein expressions with normal cell cycle. The results of the present study show promising role of AH role in accelerating the initial stage of corneal wound healing.