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Mironovich MA, Carter R, Chun Y, Foote BC, Van Horn Hendrix D, Lewin AC, Liu CC, Rogers C, Scott EM, Telle MR. Risk factors for corneal conjunctival grafting failure in dogs at four referral centers in the southern United States (203 patients): 2015-2021. Vet Ophthalmol 2024. [PMID: 38439580 DOI: 10.1111/vop.13204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/14/2024] [Accepted: 02/24/2024] [Indexed: 03/06/2024]
Abstract
OBJECTIVE To report risk factors associated with conjunctival graft failure in dogs at four referral specialty centers. PROCEDURES Records of 203 dogs (229 eyes) undergoing conjunctival graft repair of ulcerative keratitis at four hospitals from 2015 to 2021 were reviewed. Success was defined as full graft integration with globe retention at the last postoperative evaluation; vision status was reported separately. Factors assessed included patient signalment, ophthalmic examination findings, surgical factors, and follow-up information. RESULTS Conjunctival graft failure occurred in 11% (25/229) of eyes and was significantly associated with ulcer depth, with corneal perforations having increased odds of graft failure compared with descemetoceles (odds ratio [OR] = 3.22, 95% confidence interval [CI] 1.11-9.32; p = .03) and stromal ulcers (OR = 10.89 [95% CI 1.38-86.18], p = .02). Brachycephalic dogs were significantly more likely than non-brachycephalic dogs to experience graft failure (OR = 5.02 [95% CI 1.42-17.74], p < .01). Surgery on the opposite eye relative to surgeon handedness was significantly associated with an increased risk of graft failure (OR 4.28 [95% CI 1.53-11.94], p < .01). The use of 7-0 and 8-0 suture versus 9-0 (p = .03) and the use of a combined simple continuous and interrupted pattern (p = .03) were significantly associated with an increased risk of graft failure. At the last follow-up, (median 61.5 days), 87% of dogs were visual. CONCLUSIONS Corneal perforations, surgery on the opposite eye relative to surgeon handedness, suture size and pattern, and brachycephalic conformation were significantly associated with an increased risk of graft failure in this study. These characteristics can be considered when determining prognosis for ulcerative keratitis requiring surgical intervention.
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Affiliation(s)
- Melanie A Mironovich
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Renee Carter
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Yeji Chun
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Braidee C Foote
- College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA
| | | | - Andrew C Lewin
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Chin-Chi Liu
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Callie Rogers
- Department of Small Animal Clinical Sciences, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Erin M Scott
- Department of Small Animal Clinical Sciences, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Mary R Telle
- Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, USA
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Gafen HB, Liu CC, Ineck NE, Scully CM, Mironovich MA, Taylor CM, Luo M, Leis ML, Scott EM, Carter RT, Hernke DM, Paul NC, Lewin AC. Alterations to the bovine bacterial ocular surface microbiome in the context of infectious bovine keratoconjunctivitis. Anim Microbiome 2023; 5:60. [PMID: 37996960 PMCID: PMC10668498 DOI: 10.1186/s42523-023-00282-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 11/16/2023] [Indexed: 11/25/2023] Open
Abstract
BACKGROUND Infectious bovine keratoconjunctivitis (IBK) is a common cause of morbidity in cattle, resulting in significant economic losses. This study aimed to characterize the bovine bacterial ocular surface microbiome (OSM) through conjunctival swab samples from Normal eyes and eyes with naturally acquired, active IBK across populations of cattle using a three-part approach, including bacterial culture, relative abundance (RA, 16 S rRNA gene sequencing), and semi-quantitative random forest modeling (real-time polymerase chain reaction (RT-PCR)). RESULTS Conjunctival swab samples were obtained from eyes individually classified as Normal (n = 376) or IBK (n = 228) based on clinical signs. Cattle unaffected by IBK and the unaffected eye in cattle with contralateral IBK were used to obtain Normal eye samples. Moraxella bovis was cultured from similar proportions of IBK (7/228, 3.07%) and Normal eyes (1/159, 0.63%) (p = 0.1481). Moraxella bovoculi was cultured more frequently (p < 0.0001) in IBK (59/228, 25.88%) than Normal (7/159, 4.40%) eyes. RA (via 16 S rRNA gene sequencing) of Actinobacteriota was significantly higher in Normal eyes (p = 0.0045). Corynebacterium variabile and Corynebacterium stationis (Actinobacteriota) were detected at significantly higher RA (p = 0.0008, p = 0.0025 respectively) in Normal eyes. Rothia nasimurium (Actinobacteriota) was detected at significantly higher RA in IBK eyes (p < 0.0001). Alpha-diversity index was not significantly different between IBK and Normal eyes (p > 0.05). Alpha-diversity indices for geographic location (p < 0.001), age (p < 0.0001), sex (p < 0.05) and breed (p < 0.01) and beta-diversity indices for geographic location (p < 0.001), disease status (p < 0.01), age (p < 0.001), sex (p < 0.001) and breed (p < 0.001) were significantly different between groups. Modeling of RT-PCR values reliably categorized the microbiome of IBK and Normal eyes; primers for Moraxella bovoculi, Moraxella bovis, and Staphylococcus spp. were consistently the most significant canonical variables in these models. CONCLUSIONS The results provide further evidence that multiple elements of the bovine bacterial OSM are altered in the context of IBK, indicating the involvement of a variety of bacteria in addition to Moraxella bovis, including Moraxella bovoculi and R. nasimurium, among others. Actinobacteriota RA is altered in IBK, providing possible opportunities for novel therapeutic interventions. While RT-PCR modeling provided limited further support for the involvement of Moraxella bovis in IBK, this was not overtly reflected in culture or RA results. Results also highlight the influence of geographic location and breed type (dairy or beef) on the bovine bacterial OSM. RT-PCR modeling reliably categorized samples as IBK or Normal.
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Affiliation(s)
- Hannah B Gafen
- Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA, 70803, USA
| | - Chin-Chi Liu
- Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA, 70803, USA
| | - Nikole E Ineck
- Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA, 70803, USA
| | - Clare M Scully
- Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA, 70803, USA
| | - Melanie A Mironovich
- Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA, 70803, USA
| | - Christopher M Taylor
- Department of Microbiology, Immunology, and Parasitology, School of Medicine, Louisiana State University, 2020 Gravier St, New Orleans, LA, 70112, USA
| | - Meng Luo
- Department of Microbiology, Immunology, and Parasitology, School of Medicine, Louisiana State University, 2020 Gravier St, New Orleans, LA, 70112, USA
| | - Marina L Leis
- Department of Small Animal Clinical Sciences, Western College of Veterinary Medicine, 52 Campus Dr, Saskatoon, SK, S7N 5B4, Canada
| | - Erin M Scott
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, 602 Tower Rd, Ithaca, NY, 14853, USA
| | - Renee T Carter
- Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA, 70803, USA
| | - David M Hernke
- Department of Ambulatory Medicine and Theriogenology, Cummings School of Veterinary Medicine, Tufts University, 200 Westboro Rd, North Grafton, MA, 01536, USA
| | - Narayan C Paul
- Texas A&M Veterinary Medical Diagnostic Laboratory, Texas A&M University, 483 Agronomy Rd, College Station, TX, 77843, USA
| | - Andrew C Lewin
- Department of Veterinary Clinical Sciences, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA, 70803, USA.
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Mills EP, Liu CC, Mironovich MA, Taylor CM, Luo M, Emelogu U, Scott EM, Leis ML, Carter RT, Camacho-Luna P, Lewin AC. Relationship between the bacterial ocular surface microbiota and outcomes for cats with feline herpesvirus type 1 ocular surface disease. Vet Ophthalmol 2023. [PMID: 37876296 DOI: 10.1111/vop.13157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 10/12/2023] [Accepted: 10/18/2023] [Indexed: 10/26/2023]
Abstract
OBJECTIVE Feline herpesvirus 1 (FHV-1) causes ocular surface disease in domestic cats. The purpose of this study was to assess the relationship between bacterial ocular surface microbiota and outcomes for cats with FHV-1 ocular surface disease. ANIMALS STUDIED Twenty-two shelter-housed cats with confirmed FHV-1 ocular surface disease. PROCEDURES Animals were grouped according to FHV-1 shedding and ocular clinical scores following intervention: worsened outcome (WorOut, n = 11) or improved outcome (ImpOut, n = 11). Scoring and conjunctival sampling were completed on Days 1 and 8 of twice daily antiviral treatment. Bacterial DNA was extracted and submitted for 16S rRNA gene sequencing. Real-time polymerase chain reaction was performed for selected bacterial species. Overall DNA concentration between groups was assessed. RESULTS Bacterial microbiota relative abundance composition was significantly different between ImpOut and WorOut groups (weighted UniFrac p = .006). Alpha diversity was significantly higher in the ImpOut group compared with the WorOut group (Shannon p = .042, Simpson's p = .022, Pielou's p = .037). Differences in the relative abundance of various phyla and species were detected between groups. Total DNA concentration was higher in the WorOut group compared with the ImpOut group (p = .04). Feline GAPDH (p = .001) and Bilophila wadsworthia (p = .024) copy number was significantly higher in the ImpOut group compared with the WorOut group. CONCLUSIONS The results highlight the important relationship between the bacterial ocular surface microbiota and FHV-1 infection outcomes in cats treated with antiviral medications. Low bacterial species diversity, higher overall DNA (presumed predominantly bacterial) load, and certain bacterial phyla/species were associated with poor outcomes for cats with FHV-1 ocular disease.
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Affiliation(s)
- Erinn P Mills
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Chin-Chi Liu
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Melanie A Mironovich
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Christopher M Taylor
- Department of Microbiology, Immunology, and Parasitology, Health Sciences Center, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Meng Luo
- Department of Microbiology, Immunology, and Parasitology, Health Sciences Center, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Ugochi Emelogu
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Erin M Scott
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Marina L Leis
- Department of Small Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Renee T Carter
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Pilar Camacho-Luna
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Andrew C Lewin
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
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Gafen HB, Liu CC, Ineck NE, Scully CM, Mironovich MA, Guarneri L, Taylor CM, Luo M, Leis ML, Scott EM, Carter RT, Lewin AC. Relative and Quantitative Characterization of the Bovine Bacterial Ocular Surface Microbiome in the Context of Suspected Ocular Squamous Cell Carcinoma. Animals (Basel) 2023; 13:1976. [PMID: 37370486 DOI: 10.3390/ani13121976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/31/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
The ocular surface microbiome is altered in certain disease states. The aim of this study was to characterize the bovine bacterial ocular surface microbiome (BBOSM) in the context of ocular squamous cell carcinoma (OSCC). The conjunctiva of normal (n = 28) and OSCC (n = 10) eyes of cows aged 2 to 13 years from two farms in Louisiana and Wyoming were sampled using individual sterile swabs. DNA extraction followed by 16S ribosomal ribonucleic acid (rRNA) gene sequencing and real-time polymerase chain reaction (RT-PCR) were performed to, respectively, assess the relative and absolute BBOSM. Discriminant analysis (DA) was performed using RT-PCR data, and relative abundance analysis was performed using 16S rRNA gene sequencing data. The 11 most abundant phyla in both normal and OSCC-affected cows were identified using 16S rRNA gene sequencing analysis. The relative abundance of Euryarchaeota was found to be significantly lower (p = 0.0372) in OSCC eyes compared to normal eyes. Relative abundance differences within and between geographic locations were also identified. Quadratic DA categorized samples as OSCC or normal with 100% sensitivity and 83.3-100% specificity. Relative abundance analysis identified relative BBOSM phylum alterations in OSCC. Quadratic DA can be used to accurately categorize BBOSM from normal and OSCC ocular surface samples.
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Affiliation(s)
- Hannah B Gafen
- Department of Veterinary Clinical Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Chin-Chi Liu
- Department of Veterinary Clinical Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Nikole E Ineck
- Department of Veterinary Clinical Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Clare M Scully
- Department of Veterinary Clinical Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Melanie A Mironovich
- Department of Veterinary Clinical Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Lauren Guarneri
- Department of Pathobiological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Christopher M Taylor
- Department of Microbiology, Immunology, and Parasitology, School of Medicine, Louisiana State University, New Orleans, LA 70112, USA
| | - Meng Luo
- Department of Microbiology, Immunology, and Parasitology, School of Medicine, Louisiana State University, New Orleans, LA 70112, USA
| | - Marina L Leis
- Department of Small Animal Clinical Sciences, Western College of Veterinary Medicine, Saskatoon, SK S7N 5B4, Canada
| | - Erin M Scott
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Renee T Carter
- Department of Veterinary Clinical Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Andrew C Lewin
- Department of Veterinary Clinical Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
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Lewin AC, Ineck NE, Mironovich MA, Marino ME, Liu CC, Emelogu U, Mills EP, Camacho-Luna P, Carter RT. Surveillance for feline herpesvirus type 1 mutation and development of resistance in cats treated with antiviral medications. Front Vet Sci 2023; 10:1197249. [PMID: 37275610 PMCID: PMC10232796 DOI: 10.3389/fvets.2023.1197249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 05/02/2023] [Indexed: 06/07/2023] Open
Abstract
Feline herpesvirus type 1 (FHV-1) commonly causes ocular surface disease in cats and is treated with antiviral medications targeting viral DNA polymerase (UL30/42). Herein, we describe a method to assess the FHV-1 genome for mutation development and to assess the functional impact of mutations, if present. Fourteen shelter-housed domestic cats with FHV-1 ocular surface disease were assigned to one of four treatment groups: placebo (n = 3), cidofovir 0.5% ophthalmic solution (n = 3), famciclovir oral solution (n = 5), or ganciclovir 0.15% ophthalmic solution (n = 3). Swabs were collected before (day 1) and after (day 8) 1 week of twice-daily treatments to isolate viable FHV-1. Viral DNA was extracted for sequencing using Illumina MiSeq with subsequent genomic variant detection between paired day 1 and day 8 isolates. Plaque reduction assay was performed on paired isolates demonstrating non-synonymous variants. A total of 171 synonymous and 3 non-synonymous variants were identified in day 8 isolates. No variants were detected in viral UL23, UL30, or UL42 genes. Variant totals were not statistically different in animals receiving antiviral or placebo (p = 0.4997). A day 8 isolate from each antiviral treatment group contained a single non-synonymous variant in ICP4 (transcriptional regulator). These 3 isolates demonstrated no evidence of functional antiviral resistance when IC50 was assessed. Most (10/14 pairs) day 1 and 8 viral isolate pairs from the same host animal were near-identical. While functional variants were not detected in this small sample, these techniques can be replicated to assess FHV-1 isolates suspected of having developed resistance to antiviral medications.
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Mironovich MA, Yoon A, Marino ME, Ineck NE, Liu CC, Carter RT, Lewin AC. Evaluation of compounded cidofovir, famciclovir, and ganciclovir for the treatment of feline herpesvirus ocular surface disease in shelter-housed cats. Vet Ophthalmol 2022; 26 Suppl 1:143-153. [PMID: 36261852 DOI: 10.1111/vop.13031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 08/20/2022] [Accepted: 10/04/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To assess the efficacy of compounded cidofovir, famciclovir, and ganciclovir for the treatment of feline herpesvirus type 1 (FHV-1) ocular surface disease. ANIMALS STUDIED 132 shelter-housed cats qPCR positive for FHV-1. PROCEDURES A masked placebo-controlled study design was utilized. Animals were enrolled in one of four treatment groups: topical ocular placebo + oral placebo (n = 32), compounded cidofovir 0.5% ophthalmic solution + oral placebo (n = 32), compounded famciclovir oral solution (90 mg/kg) + topical ocular placebo (n = 32), and compounded ganciclovir 0.15% ophthalmic solution + oral placebo (n = 36). Cats were treated with each medication twice daily for 7 days and were evaluated on Day 1 and Day 8 using an ocular scoring system, body weight, and qPCR for FHV-1 viral load. RESULTS Cidofovir significantly decreased viral load from Day 1 to Day 8 compared with placebo (p = .024). Neither famciclovir nor ganciclovir decreased viral load compared with placebo (p = .14, p = .41). There was no significant improvement of ocular scores for any drug group compared with placebo (p = .62). In all groups, 65%-75% of cats improved from Day 1 to Day 8. Juvenile cats had a significant increase in weight gain compared with placebo for cidofovir (p = .025) and ganciclovir (p = .023). All corneal ulcers in placebo animals failed to heal whereas 77% of ulcers in antiviral group animals healed. CONCLUSIONS Topical ophthalmic cidofovir significantly decreased ocular FHV-1 viral shedding and increased weight gain in juvenile cats. Ganciclovir increased weight gain in juvenile cats. Compounded famciclovir demonstrated limited efficacy for the treatment of FHV-1 ocular surface disease in shelter-housed cats.
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Affiliation(s)
- Melanie A Mironovich
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Angela Yoon
- Department of Small Animal Clinical Sciences, Veterinary Medicine and Biomedical Sciences, Texas A&M University, Texas, USA
| | - Morgan E Marino
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Nikole E Ineck
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Chin-Chi Liu
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Renee T Carter
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Andrew C Lewin
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA
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Mironovich MA, Mitchell MS, Liu CC, Carter RT, Lewin AC. The effect of topical ophthalmic proparacaine, fluorescein, and tropicamide on subsequent bacterial cultures in healthy dogs. Vet Ophthalmol 2021; 25:44-51. [PMID: 34142756 DOI: 10.1111/vop.12914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/01/2021] [Accepted: 06/05/2021] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To determine whether tropicamide, fluorescein, and proparacaine applied topically before sample collection affect the quantity or species of bacteria isolated via aerobic culture. ANIMALS STUDIED 12 female adult research beagle cross-breed dogs. PROCEDURES A conjunctival swab was taken before and after the sequential application of proparacaine, tropicamide, and fluorescein to the same eye (P/T/F) with a five-minute gap between medications. Paired swabs were submitted for aerobic culture. Bacterial enumeration was performed using the spread plate method. Following a one-week washout period, the procedure was repeated using balanced salt solution (BSS). Following a second one-week washout period, the experiment was repeated using ofloxacin 0.3% solution. Colony counts were compared using one-way ANOVA and Tukey post hoc comparison. Bacterial species reduction was compared using a Friedman rank test and Dunn's method. RESULTS The bacterial colony count for P/T/F and BSS was significantly higher than the ofloxacin group (p = 0.0052, p = 0.0022). There was no significant difference for colony counts between P/T/F and BSS (p = 0.9295). The most frequently isolated bacteria included: Psychrobacter spp., Staphylococcus spp., Corynebacterium spp., and Streptococcus spp. The bacterial species reduction for P/T/F and BSS was significantly lower than for ofloxacin (p < 0.0001, p = 0.0160). There was no significant difference for species reduction between P/T/F and BSS (p = 0.3749). CONCLUSIONS The application of proparacaine, tropicamide, and fluorescein did not significantly decrease the amount or species of bacteria isolated from the conjunctiva in this canine population. The application of these solutions prior to ocular swab collection in healthy dogs is unlikely to affect subsequent culture results.
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Affiliation(s)
- Melanie A Mironovich
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA
| | - Maria S Mitchell
- Louisiana Animal Disease Diagnostic Laboratory, Louisiana State University, Baton Rouge, LA, USA
| | - Chin-Chi Liu
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA
| | - Renee T Carter
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA
| | - Andrew C Lewin
- Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA
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