Antimicrobial resistance patterns of Staphylococcus species isolated from cats presented at a veterinary academic hospital in South Africa

Staphylococci isolated from cats in Italy with superficial pyoderma and allergic dermatitis: Characterisation of isolates and their resistance to antimicrobials

BACKGROUND

In cats, superficial pyoderma traditionally is considered rare and few reports are available. There is a particular lack of studies concerning Staphylococcus species associated with pyoderma in subjects affected by allergic skin diseases.

HYPOTHESIS/OBJECTIVES

(i) To evaluate the association between Staphylococcus spp. and superficial pyoderma in allergic cats and (ii) to characterise isolated staphylococci and analyse their antimicrobial resistance patterns.

ANIMALS

Forty-one cats with allergic dermatitis and superficial pyoderma in Italy.

MATERIALS AND METHODS

Skin swabs were cultured for the isolation of Staphylococcus spp. Species identification was performed by matrix-assisted laser desorption/ionisation time of flight mass spectrometry and 16S-rRNA sequencing. Staphylococcus aureus isolates were further characterised by staphylococcal protein A gene-typing. Antimicrobial susceptibility was performed by the disk diffusion method.

RESULTS

Staphylococci were isolated from 36/41 cats sampled and 39 different isolates were identified. Uneven distribution of staphylococcal species was observed among different body locations. The 39 isolates were S. aureus (n = 15), S. felis (n = 10), S. pseudintermedius (n = 8) and other staphylococci (n = 6). Eight different S. aureus spa-types associated with human clonal complexes were identified. Antimicrobial resistance was observed to penicillin (56.4%), tetracycline (46.2%), enrofloxacin (33.3%), erythromycin (28.2%), amikacin (25.6%), clindamycin (23.1%), marbofloxacin (15.4%), gentamicin (12.8%), trimethoprim-sulfamethoxazole (10.3%), chloramphenicol (7.7%) and cefoxitin/oxacillin (5.1%). Fifteen isolates (38.4%) were multidrug-resistant while meticillin resistance was associated only with S. pseudintermedius.

CONCLUSIONS AND CLINICAL RELEVANCE

These results confirm that S. aureus, S. pseudintermedius, and S. felis are frequently associated with superficial pyoderma in allergic cats. Semi-synthetic penicillins remain a suitable first-line treatment in this study, yet the high prevalence of antimicrobial resistant isolates suggests that antimicrobial susceptibility testing should be performed routinely.

Genetic diversity and antimicrobial resistance profiles of Staphylococcus pseudintermedius associated with skin and soft-tissue infections in companion animals in Lisbon, Portugal

Staphylococcus pseudintermedius is the main bacterial pathogen of skin and soft-tissue infections (SSTIs) in companion animals. Antimicrobial resistance in this species is a growing public health concern. This study aims to characterize a collection of S. pseudintermedius causing SSTIs in companion animals, establishing the main clonal lineages and antimicrobial resistance traits. The collection corresponded to all S. pseudintermedius (n = 155) causing SSTIs in companion animals (dogs, cats and one rabbit) collected between 2014 and 2018 at two laboratories in Lisbon, Portugal. Susceptibility patterns were established by disk diffusion for 28 antimicrobials (15 classes). For antimicrobials without clinical breakpoints available, a cut-off value (CO_WT) was estimated, based on the distribution of the zones of inhibition. The blaZ and mecA genes were screened for the entire collection. Other resistance genes (e.g., erm, tet, aadD, vga(C), dfrA(S1)) were searched only for those isolates showing an intermediate/resistance phenotype. For fluoroquinolone resistance, we determined the chromosomal mutations in the target genes grlA and gyrA. All the isolates were typed by PFGE following SmaI macrorestriction and isolates representative of each PFGE type were further typed by MLST. Forty-eight out of the 155  S. pseudintermedius isolates (31.0%) were methicillin-resistant (mecA ⁺, MRSP). Multidrug-resistant (MDR) phenotypes were detected for 95.8% of the MRSP and 22.4% of the methicillin-susceptible (MSSP) isolates. Of particular concern, only 19 isolates (12.3%) were susceptible to all antimicrobials tested. In total, 43 different antimicrobial resistance profiles were detected, mostly associated with the carriage of blaZ, mecA, erm(B), aph3-IIIa, aacA-aphD, cat _pC221, tet(M) and dfr(G) genes. The 155 isolates were distributed within 129 PFGE clusters, grouped by MLST in 42 clonal lineages, 25 of which correspond to new sequence types (STs). While ST71 remains the most frequent S. pseudintermedius lineage, other lineages that have been replacing ST71 in other countries were detected, including ST258, described for the first time in Portugal. This study revealed a high frequency of MRSP and MDR profiles among S. pseudintermedius associated with SSTIs in companion animals in our setting. Additionally, several clonal lineages with different resistance profiles were described, evidencing the importance of a correct diagnosis and selection of the therapy.

Epidemiology and antimicrobial resistance of staphylococci other than Staphylococcus aureus from domestic animals and livestock in Africa: a systematic review

Introduction

Staphylococci other than Staphylococcus aureus (SOSA) in animals are becoming more pathogenic and antibiotic resistant and can potentially disseminate to humans. However, there is little synthesized information regarding SOSA from animals in Africa. This systematic review provides a comprehensive overview of the epidemiology and antimicrobial resistance of SOSA in companion animals (pets) and livestock in Africa.

Method

This systematic review (PROSPERO-CRD42021252303) was conducted according to the PRISMA guidelines, and 75 eligible studies from 13 countries were identified until August 2022. Three electronic databases (Pubmed, Scopus and Web of Science) were employed.

Results

The frequently isolated SOSA were S. epidermidis, S. intermedius, S. pseudintermedius, S. xylosus, S. chromogenes, S. hyicus, M. sciuri, S. hominis, and S. haemolyticus. Thirty (40%) studies performed antibiotic susceptibility testing (AST). Penicillin (58%) and tetracycline (28%) resistance were most common across all SOSA with high rates of resistance to aminoglycosides, fluoroquinolones, and macrolides in some species. Resistance to last-resort antibiotics such as linezolid and fusidic acid were also reported. Limited data on strain typing and molecular resistance mechanisms precluded analysis of the clonal diversity of SOSA on the continent.

Conclusion

The findings of this review indicate that research on livestock-associated SOSA in Africa is lacking in some regions such as Central and Western Africa, furthermore, research on companion animals and more advanced methods for identification and strain typing of SOSA need to be encouraged.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42021252303.

Bacteriuria in Cystocentesis Samples from Cats in the United Kingdom: Prevalence, Bacterial Isolates, and Antimicrobial Susceptibilities

Bacterial urinary tract infections (UTIs) have historically been reported to be uncommon in cats; however, recent studies showed a higher prevalence. Bacterial UTIs are one of the most common reasons for the use of antimicrobial drugs in veterinary medicine. Our aim was to investigate the prevalence of positive cultures in urine samples submitted to a UK laboratory for testing, as well as prevalence of bacterial species and their antimicrobial susceptibility to commonly used antibiotics. This was a retrospective analysis of positive cultures from feline urine samples collected by cystocentesis submitted over 14 months (January 2018-February 2019). A total of 2712 samples were reviewed, of which 425 documented a positive culture (15.7%) with a total of 444 bacterial isolates. E. coli (43.7%), other Enterobacterales (26.4%), Enterococcus species (14.9%) and Staphylococcus species (9.2%) were the most commonly isolated bacteria. E. coli most commonly showed resistance to cephalexin (20.7%) and amoxicillin (16.7%). Resistance was most commonly seen against amoxicillin (64.1%) and cephalexin (52.2%) in Enterobacterales. Enterococcus species most commonly showed resistance to trimethoprim/sulfamethoxazole (94.3%). Staphylococcus species most commonly showed resistance to amoxicillin (20%). This study showed significant resistance of bacteria found in feline urine samples in the UK to frequently used antibiotics.

Prevalence of antibiotic-resistant bacteria amongst dogs in Africa: A meta-analysis review

Antimicrobial resistance (AMR) is a global public health threat for both human and veterinary medicine. Increasing evidence suggests that animals are important sources of AMR to humans; however, most of these studies focus on production animals. In order to determine the pattern of AMR in pets, mainly in dogs in Africa, a meta-analysis was performed with AMR studies conducted in African countries and published between January 2000 and January 2021 in four databases: Medline (PubMed), Scopus, Cab abstract and Google Scholar. Seven bacterial strains, namely Staphylococcus aureus, Escherichia coli, Salmonella spp., Pseudomonas aeruginosa, Streptococcus pyogenes, coagulase-negative Staphylococcus (SNC) and Staphylococcus pseudintermedius were included in this study. A total of 18 out of 234 indexed articles met the study criteria. The results revealed that multiple bacteria were resistant to various commonly used antibiotics including enrofloxacin, ciprofloxacin, gentamicin, amoxicillin, clavulanic acid, cotrimoxazole, streptomycin, tetracycline and chloramphenicol. Concerning multidrug resistance, E. coli strains came first with the highest prevalence of 98%, followed by P. aeroginosa (92%) and Salmonella spp. (53%). In contrast, the overall prevalence of multidrug resistance was low for S. aureus (18%) and S. pseudintermedius (25%). It is therefore urgent to find, as soon as possible, alternatives to replace these antibiotics, which have become ineffective in controlling these bacteria in dogs in Africa. Moreover, further metagenomic studies are needed to describe the full resistome and mobilome in dogs regardless of the bacteria.

Staphylococcus pseudintermedius: Is it a real threat to human health?

Staphylococcus Intermedius Group (SIG) staphylococci, especially Staphylococcus pseudintermedius (S. pseudintermedius), share many features with the common human Staphylococcus aureus. The similarities concern both the phenotypic characteristics and virulence of the bacteria. It is a cause of difficulties in identifying the species of isolated staphylococci. Until now, S. pseudintermedius was considered a typically animal species, of marginal importance for humans. However, it is likely that the incidence of this staphylococcus in humans is underestimated due to the misidentification of S. pseudintermedius strains as S. aureus. The cases of infections caused by S. pseudintermedius both in humans and animals described so far in the literature show that these bacteria have a similar pathogenic potential. S. pseudintermedius also produces virulence factors that favor colonization of various body regions and infections, and may affect the species composition of the natural microbiota and the host’s immune response mechanisms. Also, S. pseudintermedius may show the ability to grow in the form of a biofilm, which significantly impedes effective antibiotic therapy in clinical practice. Due to its zoonotic potential, S. pseudintermedius deserves the attention of physicians and animal owners.

Efficacy Profiles of Antimicrobials Evaluated against Staphylococcus Species Isolated from Canine Clinical Specimens

Simple Summary

Clinical cases associated with staphylococci infections are common among dogs and cats. There is evidence to suggest that staphylococci infections are increasingly becoming unresponsive to commonly used antimicrobials. This negatively impacts the ability of these infections to be treated successfully. Although resistance among these organisms has been linked to several factors, including sharing the same mechanism of action or belonging to the same group, there is evidence to suggest that cross resistance can occur between unrelated antimicrobials. The findings of this study not only confirm that antimicrobials that belong to the same group share the same mechanism of resistance and similar antimicrobial efficacy against staphylococcal infections, but also show that cross resistance occurs between unrelated antimicrobials. This should be taken into consideration when selecting antimicrobials for inclusion in the susceptibility testing panel as well as for the treatment of staphylococci infections.

Abstract

Cross-resistance occurs between antimicrobials with either similar mechanisms of action and/or similar chemical structures, or even between unrelated antimicrobials. This study employed a multivariate approach to investigate the associations between the efficacy profile of antimicrobials and the clustering of eleven different antimicrobial agents based on their efficacy profile. Records of the susceptibility of 382 confirmed Staphylococcus species isolates against 15 antimicrobials based on the disc diffusion method were included in this study. Tetrachoric correlation coefficients were computed to assess the correlations of antimicrobial efficacy profiles against Staphylococcus aureus. Principal components analysis and factor analysis were used to assess the clustering of antimicrobial susceptibility profiles. Strong correlations were observed among aminoglycosides, penicillins, fluroquinolones, and lincosamides. Three main factors were extracted, with Factor 1 dominated by the susceptibility profile of enrofloxacin (factor loading (FL) = 0.859), gentamicin (FL = 0.898), tylosin (FL = 0.801), and ampicillin (FL = −0.813). Factor 2, on the other hand, was dominated by the susceptibility profile of clindamycin (FL = 0.927) and lincomycin-spectinomycin (FL = 0.848) and co-trimazole (FL = −0.693). Lastly, Factor 3 was dominated by the susceptibility profile of amoxicillin-clavulanic acid (FL = 0.848) and cephalothin (FL = 0.824). Antimicrobials belonging to the same category or class of antimicrobial, tended to exhibit similar efficacy profiles, therefore, laboratories must choose only one of the antimicrobials in each group to help reduce the cost of antimicrobial susceptibility tests.

Epidemiology of Staphylococcus pseudintermedius in cats in Poland

Staphylococcus pseudintermedius is a well-known coagulase-positive staphylococcus that is mainly associated with the asymptomatic colonization of the skin of pets and mucous membranes. Little is still known about the occurrence of S. pseudintermedius in cats. The current study aimed to characterize the isolates of S. pseudintermedius from sick and healthy cats. This was achieved by examining their antibiotic resistance properties, biofilm formation, and genotype differences. Six hundred and seventy-six cats were swabbed (595 healthy and 81 sick cats). Thirty-five distinct S. pseudintermedius isolates from 27 cats were isolated. The prevalence of S. pseudintermedius in healthy and sick cats was 2.49% and 7.61%, respectively. In comparison, MRSP (methicillin-resistant Staphylococcus pseudintermedius) prevalence was 0.12% and 2.98%, respectively. Cats were more frequently colonized with S. pseudintermedius when kept with dogs, regardless of their health condition, with this result being statistically significant. Multidrug resistance was detected in 50%, and 38.46% of S. pseudintermedius isolates from healthy and sick cats, respectively. In contrast, genetic multidrug resistance was detected in 59% and 46.15% cases, respectively. Seven from eight isolated MRSPs were multidrug-resistant. Multi-locus sequence typing (MLST) assigned isolates to 19 types, of which 16 types submitted for the first time to the PubMLST database. The most frequently detected STs (sequence types) were 551 and 71. ST71 and ST551 were mainly isolated from cats with clinical signs of infection. All were MRSPs, regardless of cats’ health. These isolates were characterized with the most frequent antibiotic resistance at the phenotypic and genotypic level.

Diversity and Risk Factors Associated with Multidrug and Methicillin-Resistant Staphylococci Isolated from Cats Admitted to a Veterinary Clinic in Eastern Province, Saudi Arabia

Understanding the distribution, antimicrobial resistance (AMR), and risk factors associated with multidrug-resistant (MDR) and methicillin-resistant staphylococci (MRS) isolated from cats admitted to veterinary clinics may decrease the risk of MDR and MRS transmission to humans and other cats. As such, the objectives of this study were to investigate the diversity in Staphylococcus spp. recovered from different anatomical locations in healthy and diseased cats and to determine the occurrence of MDR and MRS spp. as well as possible risk factors associated with colonization in these cats. Five swabs were collected from the anus, skin, ear canal, conjunctival sac, and nares of each cat (209 healthy and 191 diseased) admitted to a veterinary clinic in Eastern Province, Saudi Arabia, between January and December 2018. Prior to sample collection, cat owners completed a questionnaire collecting information on cat demographics, health status, management, and antimicrobial usage. In total, 179 Staphylococcus isolates were recovered from healthy (n = 71) and diseased (n = 108) cats, including 94 (52.5%) coagulase-positive staphylococci (CoPS), and 85 (47.5%) coagulase-negative staphylococci (CoNS). Five Staphylococcus spp. were identified, namely, Staphylococcus aureus, Staphylococcus pseudintermedius, Staphylococcus felis, Staphylococcus capitis, and Staphylococcus saprophyticus. Staphylococcus isolates were most commonly resistant to penicillin (56.4%) and ciprofloxacin (25.7%); however, no isolate was resistant to clindamycin. Thirty (16.8%) Staphylococcus spp. (24 S. aureus and 6 S. pseudintermedius) isolates were MDR, with resistance to up to six different antibiotic classes. Only 17 (9.5%) Staphylococcus spp. (15 methicillin-resistant S. aureus and 2 methicillin-resistant S. pseudintermedius) harbored the mecA gene. Risk factor analysis showed that cats with a history of antibiotic therapy, those raised mainly indoors with a child, and those who visit a veterinary clinic for treatment were at higher risk of MDR and MRS colonization. In conclusion, MDR and MRS were common in healthy and diseased cats in Saudi Arabia. Thus, an effective antimicrobial stewardship program and further studies using a One Health approach are required to investigate the role of cats as vectors for AMR transmission to humans.

Prevalence and antimicrobial resistance of Staphylococcus species isolated from cats and dogs

Background:

Methicillin-resistant staphylococci (MRS) are an emerging global problem with serious public health concern.

Aims:

This study investigated the prevalence and antimicrobial susceptibility of commensal Staphylococcus species isolated from healthy and clinical cats and dogs.

Methods:

Nasal swab samples were collected from animals and processed using selective and semi-selective mediums. Presumptive isolates were subjected to biochemical testing and analyzed using the Phoenix automated identification and susceptibility testing system. PCRs protocols were used to screen for mecA and pvl genes.

Results:

In total, 151 pets (103 cats and 48 dogs) were enrolled, of which 14 dogs (29%) and 24 cats (23%) were colonized with various Staphylococcus species mainly originated from healthy animals. A total of 38 staphylococci isolates were collected and distributed between 24 coagulase-negative and 14 coagulase-positive staphylococci. Only 13 staphylococci strains were identified as MRS, out of which only five isolates expressed that the mecA gene exclusively originated from healthy pets.

Conclusion:

This is the first study reporting the prevalence and colonization status of staphylococci species and MRS strains isolated from cats and dogs in Libya. The study reports important information of medical and clinical importance on antimicrobial and multidrug resistance of different staphylococci strains, particularly the coagulase negative species.

Otodectic and bacterial etiology of feline otitis externa in Tripoli, Libya

Background

Feline otitis externa is a dermatological disorder with a multifactorial complex etiology.

Aim

This study aimed to investigate the prevalence of different etiological agents, particularly the parasitic and bacterial, responsible for the cases of feline otitis externa in Tripoli, Libya, and to assess the antimicrobial susceptibility of the bacterial isolates from those cases.

Methods

Cerumen and otic discharges of the suspected cats were collected for parasite detection and bacterial culture. Kirby-Bauer's disk diffusion method was used for antimicrobial susceptibility testing.

Results

The results showed that otodectic mites and bacterial causes were equally the most prevalent in those cases, with a prevalence of 47.1% each. Otodectes cynotis infestation was more frequently bilateral and severe. Staphylococcus spp. were the most prevalent among bacterial causes (75%), followed by Proteus spp. (16.6%) and Pseudomonas spp. (8.4%). Norfloxacin and gentamicin were the most effective antimicrobials against bacterial isolates, as they were effective against 83.3% and 70.8% of isolates, respectively.

Conclusion

Otodectes cynotis infestation and staphylococcal infections constituted the most common etiology of feline otitis externa in Tripoli, Libya, and norfloxacin represented a cogent antibacterial for the treatment of otitis externa.

Distribution and antimicrobial resistance profiles of bacterial species in stray cats, hospital-admitted cats, and veterinary staff in South Korea

BACKGROUND

Antimicrobial resistance is becoming increasingly important in both human and veterinary medicine. According to the One Health concept, an important step is to monitor the resistance patterns of pathogenic bacteria. In this study, the antimicrobial susceptibility patterns and trends of bacteria isolated from stray cats, hospital-admitted cats, and veterinary staff in South Korea between 2017 and 2018 were investigated.

RESULTS

The minimum inhibitory concentrations of different antibiotics for Staphylococcus spp., Enterobacteriaceae, and Enterococcus spp. were determined to establish representatives of different antibiotic classes relevant for treatment or surveillance. For Coagulase-positive and Coagulase-negative Staphylococci, resistance to fluoroquinolones was below 13%, but resistance to ampicillin and penicillin was high (20-88%). A total of 9.5, 12.1, and 40.3% of staphylococcal isolates from stray cats, hospital-admitted cats, and veterinary staff, respectively, were confirmed to be mecA positive. For Enterobacteriaceae, resistance to carbapenems, fluoroquinolones, and 3rd generation cephalosporins was low (0-11.1%). The Enterococcus spp. isolates showed no resistance to vancomycin. The antimicrobial resistance rates of the Staphylococcus spp. and Enterobacteriaceae isolates from stray cats were usually lower than those of isolates from hospital-admitted cats and veterinary staff, but the Enterococcus spp. isolates revealed the opposite. Thus, the antimicrobial resistance varied across bacterial species according to the source from which they were isolated.

CONCLUSIONS

Resistance to critically important compounds were low. However, the presence of antimicrobial resistance in cat isolates is of both public health and animal health concern.

Prevalence of Staphylococcus Species Colonization in Healthy and Sick Cats

Staphylococcus is one of the most frequently isolated genera of opportunistic bacteria in animals and human beings. Staphylococci in mammals mostly inhabit the skin and mucous membranes. The objectives of the study were to investigate the distribution of staphylococcal species in healthy and sick cats in order to find diagnostic markers. The risk factors associated with colonization were also explored. Isolates from healthy (n=520) and sick cats (n=67) were identified at the species level using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). Swabs from conjunctival sacs, nares, skin, anus, and wounds were investigated using this technique. The diversity of the Staphylococcus species was high: 26 and 17 species in healthy and sick cats, respectively, and predominantly coagulase-negative staphylococci (CoNS) were isolated. The most frequently observed were S. felis and S. epidermidis in healthy cats, whereas S. felis and S. haemolyticus were most often found in sick animals. S. aureus strains were only isolated from healthy cats, whereas the only coagulase-positive Staphylococcus (CoPS) which occurred in the sick cats group was S. pseudintermedius. The sick, more frequently than the healthy animals, were colonized with S. pseudintermedius and S. haemolyticus and the relationship was statistically significant. Mostly, regardless of the state of their health, similar Staphylococcus species were isolated from cats; therefore, particular attention should be paid during the interpretation of diagnostic results.