Prevalence of Bacterial Pathogens Isolated from Canines with Pyoderma and Otitis Externa in Korea: A Systematic Review and Meta-Analysis

Abstract

Bacterial skin infections, particularly pyoderma and otitis externa, are widespread in dogs, primarily caused by Staphylococcus and Pseudomonas species. This study evaluates the prevalence and types of bacterial pathogens in affected dogs in South Korea using a meta-analytical approach. Following the PRISMA guidelines, five electronic databases were searched for relevant studies published between 1990 and 2024. Three researchers independently performed data extraction and quality assessment. A subgroup analysis explored the variability in pathogen prevalence across studies based on bacterial genus, bacterial species, publication year, sampling year, sampling location, infection type, diagnostic method, and sample size. Publication bias was evaluated using funnel plots and Egger's regression test, with all analyses conducted using the R program. Of the 944 articles, 29 met the eligibility criteria. The pooled bacterial prevalence among infected dogs was 99.95% (95%CI: 99.85-100). Staphylococcus was the most prevalent genus (95.93%), followed by Pseudomonas (48.43%), Enterococcus (20.32%), and Escherichia (17.63%). The most common species were Staphylococcus pseudintermedius (78.89%), Staphylococcus intermedius (71.43%), and Pseudomonas aeruginosa (46.13%). This study underscores the need for comprehensive treatment strategies targeting Gram-negative and Gram-positive bacteria, emphasizing further research on antimicrobial resistance patterns and treatment efficacy to enhance canine health outcomes in South Korea.

Keywords: bacterial pathogens; dog; meta-analysis; otitis externa; pyoderma; systematic review.

Figure 1

Study selection process for the systematic review and meta-analysis (PRISMA flow chart).

Figure 2

The sampling locations of canine patients with the reported prevalence of diagnosed bacteria (n represents the number of studies).

Figure 3

Forest plot illustrating the meta-analysis of 29 studies on the prevalence of bacterial pathogens in dogs infected with pyoderma and otitis externa. (Detailed information on the studies included in this figure is provided in Table S3).

Figure 4

Forest plot illustrating the meta-analysis of 12 studies on the prevalence of methicillin-resistant Staphylococcus pseudintermedius (MRSP) in dogs infected with pyoderma and otitis externa. (Detailed information on the studies included in this figure is provided in Table S4).

Figure 5

Meta-regression of study trials on the prevalence of bacterial pathogens in dogs infected with pyoderma and otitis externa based on bacterial genus (a) and species (b). The solid lines (blue) represent the regression illustrating the relationship between the bacterial genus/species and prevalence estimates, while the dashed lines (red) indicate the 95% confidence intervals (CIs) of the regression model. The circles represent individual study trials in the meta-regression, with their size indicating their weight.

Figure 6

Funnel plot showing publication bias in the prevalence of bacterial pathogens in dogs with pyoderma and otitis externa. Black circles represent the studies included in this meta-analysis, while red circles indicate the studies imputed using the trim-and-fill method.