Equine infectious keratitis in Finland: Associated microbial isolates and susceptibility profiles.
Abstract: To retrospectively describe laboratory findings, treatment, and outcome associated with equine infectious keratitis in Finland. Unassigned: Medical records of horses diagnosed with infectious keratitis in University of Helsinki Equine Hospital from January 2007 to June 2018 were reviewed. Results: Forty-seven cases were included. Keratomycosis was diagnosed in 27 eyes and bacterial keratitis in 20 eyes. Aspergillus flavus was the most frequent fungal isolate (9/17, 53%), followed by Cylindrocarpon sp. (3/17, 18%) and Aspergillus fumigatus (2/17, 12%). Susceptibility was tested for 10/11 Aspergillus sp. isolates; all were susceptible to voriconazole while only two were susceptible to amphotericin B. Cylindrocarpon sp. isolates were resistant to both agents. Streptococcus equi subsp. zooepidemicus was the most frequent bacterial isolate (9/19, 47%), followed by other streptococci (4/19, 21%). All 13 Streptococcus sp. isolates were susceptible to penicillin, and all tested isolates (n = 11) were also susceptible to chloramphenicol. Mean duration of medical treatment was longer in fungal keratitis (38 days) than in bacterial keratitis (25 days) (P < .001). Twenty-six of the eyes underwent globe-sparing surgery in addition to medical therapy. Recovery was achieved in 66% (31/47) of all cases and in 59% (16/27) and 75% (15/20) (P = .264) of cases with keratomycosis and bacterial keratitis, respectively. Conclusions: Although Aspergillus sp. and S zooepidemicus were the most frequently encountered isolates, cytology, culture, and susceptibility testing are essential to differentiate bacterial and fungal keratitis and guide the clinician to choose the most efficient treatment.
© 2019 The Authors. Veterinary Ophthalmology published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Ophthalmologists.
Publication Date: 2019-07-31 PubMed ID: 31364808PubMed Central: PMC7004187DOI: 10.1111/vop.12701Google Scholar: Lookup
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Summary
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The research is a retrospective study on the laboratory findings, treatments, and outcomes related to equine infectious keratitis in Finland, utilizing medical records of diagnosed cases from 2007 to 2018 at the University of Helsinki Equine Hospital.
Study Design and Dataset
- The research was a retrospective study using medical records from the University of Helsinki Equine Hospital.
- The timespan of the studied records was from January 2007 to June 2018.
- The study examined 47 cases of equine infectious keratitis.
Findings and Implications
- Out of the 47 cases studied, 27 were diagnosed with keratomycosis (fungal infection of the eye) and 20 with bacterial keratitis.
- The most common fungal isolate was Aspergillus flavus, found in 53% of the samples, followed by Cylindrocarpon sp. (18%) and Aspergillus fumigatus (12%).
- All of the 10 Aspergillus sp. were susceptible to voriconazole, a treatment for fungal infections. Only two were susceptible to a second treatment, amphotericin B. In contrast, Cylindrocarpon sp. was resistant to both treatments.
- Streptococcus equi subsp. zooepidemicus was the most common bacterial isolate (47%), followed by other streptococci (21%).
- All 13 Streptococcus sp. isolates tested were susceptible to the antibiotics penicillin and chloramphenicol.
- Length of treatment was longer for fungal keratitis (38 days) than for bacterial keratitis (25 days).
- In addition to medical therapy, 26 eyes went through globe-sparing surgery.
- The recovery rate was 66% for all cases. Breakdown by condition showed a 59% recovery rate for keratomycosis and a 75% rate for bacterial keratitis.
Conclusion of the Research
- The study indicates that while Aspergillus sp. and Streptococcus zooepidemicus were the most frequently identified isolates, cytology, culture, and susceptibility testing are crucial to differentiate between bacterial and fungal keratitis.
- This differentiation is vital in helping clinicians choose the most effective treatment for each case, which can lead to better outcomes for the affected horses.
Cite This Article
APA
Mustikka MP, Grönthal TSC, Pietilä EM.
(2019).
Equine infectious keratitis in Finland: Associated microbial isolates and susceptibility profiles.
Vet Ophthalmol, 23(1), 148-159.
https://doi.org/10.1111/vop.12701 Publication
Researcher Affiliations
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland.
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland.
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland.
MeSH Terms
- Animals
- Anti-Bacterial Agents
- Bacteria / drug effects
- Bacterial Infections / epidemiology
- Bacterial Infections / microbiology
- Bacterial Infections / veterinary
- Drug Resistance, Bacterial
- Female
- Finland / epidemiology
- Horse Diseases / epidemiology
- Horse Diseases / microbiology
- Horses
- Keratitis / epidemiology
- Keratitis / microbiology
- Keratitis / veterinary
- Male
- Retrospective Studies
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