Emergence and genomic chion of Proteus mirabilis harboring blaNDM-1 in Korean companion dogs.

Proteus mirabilis is a commensal bacterium dwelling in the gastrointestinal (GI) tract of humans and animals. Although New Delhi metallo-ß-lactamase 1 (NDM-1) producing P. mirabilis is emerging as a threat, its epidemiology in our society remains largely unknown. LHPm1, the first P. mirabilis isolate harboring NDM-1, was detected from a companion dog that resides with a human owner. The whole-genome study revealed 20 different antimicrobial resistance (AMR) genes against various classes of antimicrobial agents, which corresponded to the MIC results. Genomic regions, including MDR genes, were identified with multiple variations and visualized in a comparative manner. In the whole-genome epidemiological analysis, multiple phylogroups were identified, revealing the genetic relationship of LHPm1 with other P. mirabilis strains carrying various AMR genes. These genetic findings offer comprehensive insights into NDM-1-producing P. mirabilis, underscoring the need for urgent control measures and surveillance programs using a "one health approach".

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.

Isolation, characterization and antibiotic resistance of Proteus mirabilis from Belgian broiler carcasses at retail and human stool.

Proteus mirabilis is an important pathogen involved in human urinary tract infections, and also more isolated from stools of patients with diarrheal disease than from healthy patients. The role of food, especially poultry products as source for human infection and multi-resistant strains remains unclear. As a resident in broilers' intestines, P. mirabilis can contaminate broiler carcasses due to slaughter practices, and be a risk for human infection. The present study evaluated the performance of five isolation media, and subsequently examined the presence of P. mirabilis on broiler carcasses at retail. Additionally, isolates were characterized by the Dienes' test, repetitive element PCR fingerprinting and pulsed-field gel electrophoresis, and their antibiotic resistance profile determined. Using a combined isolation protocol on blood agar, xylose lysine deoxycholate agar and violet red bile glucose agar, P. mirabilis was isolated from 29 out of 80 broiler carcasses (36.25%) with a mean contamination level of 2.25 ± 0.50 log10 CFU/g. A high strain heterogeneity was present in isolates from broilers and human stool. The same strains were not shared, but the antibiotic resistance profiling was similar. A role of poultry products as source for human infection should be taken into account.

Multidrug-resistant Proteus mirabilis isolates carrying blaOXA-1 and blaNDM-1 from wildlife in China: increasing public health risk.

The emergence of multidrug resistance (MDR) in Proteus mirabilis clinical isolates is a growing public health concern and has serious implications for wildlife. What is the role of wildlife has been become one of the hot issues in disseminating antimicrobial resistance. Here, 54 P. mirabilis isolates from 12 different species were identified. Among them, 25 isolates were determined to be MDR by profile of antimicrobial susceptibility; 10 MDR P. mirabilis isolates were subjected to comparative genomic analysis by whole genome sequencing. Comprehensive analysis showed that chromosome of P. mirabilis isolates mainly carries multidrug-resistance complex elements harboring resistance to carbapenem genes blaOXA-1 , blaNDM-1 , and blaTEM-1 . Class I integron is the insertion hotspot of IS26; it can be inserted into type I integron at different sites, thus forming a variety of multiple drug resistance decision sites. At the same time, Tn21, Tn7, and SXT/R391 mobile elements cause widespread spread of these drug resistance genes. In conclusion, P. mirabilis isolates from wildlife showed higher resistance to commonly used clinic drugs comparing to those from human. Therefore, wild animals carrying MDR clinical isolates should be paid attention to by the public health.

Clinical significance of Proteus mirabilis bacteriuria in dogs, risk factors and antimicrobial susceptibility.

The objectives of this study were to describe the in vitro antimicrobial susceptibility and clinical significance of Proteus mirabilis in canine bacteriuria and to identify the risk factors associated with P. mirabilis urinary tract infections. This is a retrospective observational study of 48 P. mirabilis-positive canine urinary cultures. Only 22 of the 48 P. mirabilis isolates (45.8%) were non-susceptible to at least one tested antimicrobial. Most P. mirabilis isolates (98%) were susceptible to enrofloxacin, 93.7% to amoxicillin/clavulanic acid, and 85.4% to ampicillin, cephalothin, and trimethoprim-sulfamethoxazole. Five multidrug-resistant isolates were detected (10.4%). A significant increase in antimicrobial resistance was observed over the study period. Positive P. mirabilis cultures were associated with bacterial cystitis in 36 of 39 dogs (92.3%), pyelonephritis in 2 of 39 dogs (5.1%), and one dog had both bacterial cystitis and pyelonephritis (2.5%). There was no subclinical bacteriuria. Most urinary tract infections were complicated as risk factors were identified in 37 of 39 dogs (94.8%). The most commonly identified risk factors were the presence of a contaminated peri-vulvar area with urine/feces or a hypoplastic vulva. To conclude, P. mirabilis bacteriuria was associated with upper and lower urinary tract infections in this study and was found more frequently in complicated bacterial cystitis. Multidrug-resistant isolates and increased P. mirabilis antimicrobial resistance have been identified over the last 10 years, but most isolates remain susceptible to first-line antimicrobials such as amoxicillin and trimethoprim-sulfamethoxazole.

Cette étude a pour but d'évaluer la sensibilité in vitro aux antibiotiques de Proteus mirabilis lors de bactériurie chez le chien, son importance clinique et les facteurs de risques d'infection urinaire associée à Proteus mirabilis. Il s'agit d'une étude rétrospective, observationnelle reposant sur 48 cultures urinaires positives à Proteus mirabilis chez le chien. Seuls 22 des 48 isolats (45,8 %) n'étaient pas sensibles à au moins un des antibiotiques testés. La majorité des isolats (98 %) étaient sensibles à l'enrofloxacine, 93,7 % à l'amoxicilline/acide clavulanique et 85,4 % à l'ampicilline, céphalothine et trimethoprime-sulfamethoxazole. Cinq isolats multi-résistants ont été détectés (10,4 %). Une augmentation significative de la résistance a été observée sur la période étudiée. Une cystite bactérienne a été diagnostiquée chez 36 des 39 chiens inclus (92,3 %), une pyélonéphrite chez deux chiens (5,1 %) et un chien présentait des signes de cystite bactérienne et de pyélonéphrite (2,5 %). Aucune bactériurie subclinique n'a été identifiée; la plupart des infections urinaires étaient compliquées (94,8 %). Les facteurs de risque les plus rencontrés sont la contamination de la région péri-vulvaire ou la présence d'une vulve hypoplasique. En conclusion, Proteus mirabilis doit être suspecté en cas de cystite bactérienne compliquée. Des isolats multi-résistants ont été identifiés et une hausse de la résistance a été observée au cours des dix dernières années. La plupart reste sensible aux antibiotiques de premières lignes que sont l'amoxicilline et trimethoprime-sulfamethoxazole.(Traduit par les auteurs).

Proteus mirabilis causing cellulitis in broiler chickens.

Given the need to understand the virulence profile of Proteus mirabilis isolates from cellulitis in broiler chickens and their ability to cause lesions, the present study aimed to characterize genotypically and phenotypically the virulence profiles of two strains of P. mirabilis isolated from cellulitis in broilers, as well as to evaluate their ability to experimentally reproduce the lesions in vivo. The strain with the highest virulence potential (LBUEL-A33) possessed mrpA, pmfA, ucaA, atfA (fimbriae), zapA, ptA (proteases), hpmA (hemolysin), and ireA (siderophore) genes, formed a very strong biofilm, and expressed the pattern of aggregative adhesion and cytotoxicity in Vero cells. The strain with the lowest virulence potential (LBUEL-A34) did not present the pmfA and ucaA genes, but expressed the pattern of aggregative adhesion, formed a strong biofilm, and did not show cytotoxicity. Both strains developed cellulitis in an animal model within 24 h post-inoculation (PI), and the degree of lesions was not significantly altered up to 120 h PI. The LBUEL-A33 strain was also inoculated in combination with an avian pathogenic Escherichia coli (APEC 046), and the lesions showed no significant changes from the individual inoculation of these two strains. Histological analysis showed that the LBUEL-A33 strain developed characteristic cellulitis lesions. Thus, both strains of P. mirabilis isolated in our study have several virulence factors and the ability to develop cellulitis in broilers.

Extended-spectrum ß-lactamase-producing Proteus mirabilis with multidrug resistance isolated from raw chicken in Singapore: Genotypic and phenotypic analysis.

OBJECTIVES: Proteus mirabilis is ubiquitous in soil and water. It is an important catheter-associated urinary tract pathogen and has reportedly been associated with antimicrobial-resistant infections. This study reports the draft genome of a multidrug-resistant P. mirabilis isolated from raw retail chicken meat in Singapore. METHODS: The P. mirabilis strain was isolated on BrillianceTM ESBL Agar and was screened for antimicrobial susceptibility against 29 antimicrobial agents using a MicroScan® Neg MIC Panel Type 44. The double-disk synergy test (DDST) was used for confirmation of extended-spectrum ß-lactamase (ESBL) production. Genomic DNA from the pure culture isolate was extracted and was sent for sequencing based on Illumina HiSeq 2500 technology. Further bioinformatics analysis was performed using online tools available at the Center for Genomic Epidemiology. RESULTS: Species identification of the isolate was performed by KmerFinder. Antimicrobial susceptibility testing of the isolate showed multidrug resistance to broad-spectrum ß-lactams, fluoroquinolones and aminoglycosides, among others. ESBL production was confirmed by the DDST. A total of 29 antimicrobial resistance genes were detected by ResFinder. CONCLUSION: To the best of our knowledge, this is the first report of the whole-genome sequence of a multidrug-resistant P. mirabilis producing an ESBL from raw chicken meat in Singapore. This indicates that raw meat in Singapore can be a reservoir for drug-resistant pathogens.

Genotypic and phenotypic profiles of virulence factors and antimicrobial resistance of Proteus mirabilis isolated from chicken carcasses: potential zoonotic risk.

Proteus mirabilis is an opportunistic pathogen often associated with a variety of human infections acquired both in the community and in hospitals. In this context, the present work aimed to evaluate the genotypic and phenotypic characteristics of the virulence factors and antimicrobial resistance determinants of 32 P. mirabilis strains isolated from chicken carcasses in a poultry slaughterhouse in the north of the state of Paraná, Brazil, in order to assess a potential zoonotic risk. The isolates presented a variety of virulence genes that contribute to the development of infection in humans. The mrpA, pmfA, atfA (fimbriae), ireA (siderophores receptor), zapA, ptA (Proteases), and hpmA (hemolysin) genes were found in 32 (100%) isolates and ucaA (fimbriae) in 16 (50%). All isolates showed aggregative adherence in HEp-2 cells and formed biofilms. Of all strains, 27 (84.38%) showed cytotoxic effects in Vero cells. Antimicrobial susceptibility was tested using 20 antimicrobials, in which 25 (78.13%) strains were considered multidrug-resistant. The presence of blaESBL and blaampC genes conferring resistance to ß-lactams and qnr to quinolones were also detected in the isolates after presumption in the phenotypic test, in which 7 (21.88%) isolates contained the CTX-M-2 group, 11 (34.38%) contained CIT group and 19 (59.38%) contained qnrD. Therefore, chicken carcasses contaminated with P. mirabilis may pose a health risk to the consumer, as these isolates have a variety of virulence and antimicrobial resistance characteristics that can be found in P. mirabilis strains isolated from human infections.

Clonal relatedness of Proteus mirabilis strains causing urinary tract infections in companion animals and humans.

Proteus mirabilis is a major cause of urinary tract infection (UTI) in humans and companion animals. This study aimed to evaluate the antimicrobial resistance, virulence and clonal relatedness of P. mirabilis isolated from dogs, cats and humans with UTI. P. mirabilis isolated from companion animals (N = 107) and humans (N = 76) with UTI were compared by PFGE analysis after overnight NotI macro-restriction using Dice/UPGMA with a 1.5% tolerance. Strains were characterized for antimicrobial resistance by disk diffusion. Twenty-four resistance genes and four virulence genes were screened by PCR. Thirty-nine clusters (similarity >80%) and 73 single pulse-types were detected. Nine clusters included P. mirabilis isolated from community and hospital patients, including strains with 100% similarity. A high number of clusters (43.6%, n = 17/39) included strains from companion animals and humans. Similarity between some companion animal and human strains varied between 80-100%. One strain from a dog was 100% similar to one human community-acquired P. mirabilis. One P. mirabilis from a cat was found to be 94.7% and 92.4% similar to community and hospital patient strains, respectively. P. mirabilis CMY-2-producers did not cluster all together. Nevertheless, cluster C36 included five P. mirabilis from companion animals (similarity 85.8%-95.7%), of which, four (80%) were multidrug-resistant CMY-2-producers. This study shows that companion animals and humans become infected with closely related P. mirabilis strains. The high number of clusters containing companion animals and human strains points to the zoonotic nature of P. mirabilis. These results underline the potential role of companion animals as reservoirs and in the dissemination of uropathogenic P. mirabilis to humans and vice versa.

Isolation and characterization of a group of new Proteus bacteriophages.

Four lytic Proteus bacteriophages, PM75, PM85, PM93, and PM116, which are active against multi-drug-resistant strains of P. mirabilis, were isolated from cattle and poultry samples. According to electron microscopy data, all of the investigated phages belonged to the family Podoviridae. They all demonstrated lytic activity against sensitive strains of P. mirabilis, and three of the phages, PM85, PM93, and PM116, are potential candidates for use in antibacterial treatment. The genomes and putative proteins of bacteriophages PM85, PM93, and PM116 were similar to those of Proteus phage vB_PmiP_Pm5460 [KP890822], and the investigated phages formed a distinct clade within the genus Sp6virus, subfamily Autographivirinae. The genome sequence of phage PM75 was similar to that of a previously described Proteus phage, PM16 [KF319020], and both of them demonstrated low nucleotide sequence identity to the genomes of the other most similar phages, namely, Vibrio phage VP93, Pantoea phage LIMElight, and KP34-like bacteriophages. According to cluster analysis of the complete genome sequences and phylogenetic analysis of the proteins essential for their life cycle, phages PM75 and PM16 are distinct from other similar phages from the phiKMV supergroup and should be recognized as constituting a new genus, "Pm16virus", within the subfamily Autographivirinae.

Occurrence of Salmonella genomic island 1 (SGI1) in two African Proteus mirabilis strains isolated from diseased chicken flocks.

Two P. mirabilis strains, PmSHR21 and PmSHR38, were collected from chicken flocks in Sharkia Governorate, Egypt in 2016. The two strains showed multidrug-resistance (MDR) phenotypes and were detected to harbour I) floR and sul1 genes conferring resistance to florfenicol and chloramphenicol, and sulfonamides, respectively, II) a ~1.9 kbp class 1 integron containing aadA2-lnuF genes conferring resistance to spectinomycin and streptomycin, and lincosamides, respectively. Interestingly, the two strains were detected to contain SGI1 variant, SGI1-W and inserted between the 3' end of the chromosomal trmE gene and the hipB/hipA toxin/antitoxin homologue. Fingerprinting by ERIC-PCR of the two poultry strains identified in this study and the two human SGI1-carrying P. mirabilis strains described recently in our study showed identical ERIC-pattern between SGI1-W-carrying poultry and human strains, suggesting that they might be clonally related. The detection of SGI1 and its variants in P. mirabilis isolated from humans and chicken flocks in Egypt clarify the geographical and biological spreading through an inter-transmission pathway. To the best of our knowledge, this is the first study detecting SGI1-positive P. mirabilis isolated from chicken flocks in Africa.

Necrotizing suppurative nephritis in a Japanese black feedlot steer due to Proteus mirabilis infection.

A Japanese black feedlot steer suddenly died after exhibiting astasia and cramping of the extremities. Necropsy of the animal revealed that the right kidney was enlarged and pale with severe nephrolithiasis. The urinary bladder displayed mucosal hemorrhage. Upon bacteriological investigation, Proteus mirabilis was isolated from the liver, spleen, right kidney, lungs and urine. Histopathological examination revealed necrotizing suppurative nephritis with the presence of numerous gram-negative bacilli and fibrinous suppurative cystitis with no bacilli. Immunohistochemical analysis revealed that the bacteria and cytoplasm of the macrophages stained positively with P. mirabilis antiserum. Electron microscopy revealed the presence of numerous bacteria in the renal tubules. To our knowledge, this is the first report describing the histopathological aspects of nephritis caused by P. mirabilis in cattle.

In vitro activity of three commercial bacteriophage cocktails against multidrug-resistant Escherichia coli and Proteus spp. strains of human and non-human origin.

OBJECTIVES: Bacteriophages may represent a therapeutic alternative to treat infections caused by multidrug-resistant (MDR) pathogens. However, studies analysing their activity against MDR Enterobacteriaceae are limited. METHODS: The in vitro lytic activity of three commercial bacteriophage cocktails (PYO, INTESTI and Septaphage) was evaluated against 70 Escherichia coli and 31 Proteus spp. of human and non-human origin. Isolates were characterised by phenotypic and genotypic methods and included 82 MDR strains [44 extended-spectrum-ß-lactamase (ESBL)-producers (18 CTX-M-15-like, including ST131/ST648 E. coli); 27 plasmid-mediated AmpC ß-lactamase (pAmpC)-producers (23 CMY-2-like, including ST131 E. coli); 3 ESBL+pAmpC-producers; and 8 carbapenemase-producers]. Phage susceptibility was determined by the spot test. RESULTS: E. coli susceptibility to PYO, INTESTI and Septaphage was 61%, 67% and 9%, whereas that of Proteus spp. was 29%, 39% and 19%, respectively. For the subgroup of ESBL-producing E. coli/Proteus spp., the following susceptibility rates were recorded: PYO, 57%; INTESTI, 59%; and Septaphage, 11%. With regard to pAmpC-producers, 59%, 70% and 11% were susceptible to PYO, INTESTI and Septaphage, respectively. Five of eight carbapenemase-producers and three of four colistin-resistant E. coli were susceptible to PYO and INTESTI. CONCLUSIONS: This is the first study analysing the activity of the above three cocktails against well-characterised MDR E. coli and Proteus spp. The overall narrow spectrum of activity observed could be related to the absence of specific bacteriophages targeting these contemporary MDR strains that are spreading in different settings. Therefore, bacteriophages targeting emerging MDR pathogens need to be isolated and integrated in such biopreparations.

Effects of astaxanthin and emodin on the growth, stress resistance and disease resistance of yellow catfish (Pelteobagrus fulvidraco).

Yellow catfish (Pelteobagrus fulvidraco) has become a commercially important fish species in China and eastern Asia. High-density aquaculture has led to congestion and excessive stress and contributed to bacterial infection outbreaks that have caused high mortality. We investigated the effects of dietary supplementation with astaxanthin and emodin alone and in combination on the growth and stress resistance of yellow catfish. After 60 days of feeding, each group of fish (control, astaxanthin, emodin, and astaxanthin plus emodin (combination) groups) was exposed to acute crowding stress for 24 h, and a subsample of fish from the four groups was challenged with the bacterial septicemia pathogen Proteus mirabilis after the end of the crowding stress experiment. Compared with the control, the astaxanthin and emodin groups showed increases in serum total protein (TP), hepatic superoxide dismutase (SOD) activity and hepatic heat shock proteins 70 (HSP70) mRNA levels at 12 and 24 h after the initiation of crowding stress. The combination group exhibited increases in alanine aminotransferase (ALT) activity, aspartate aminotransferase (AST) activity, serum TP, hepatic SOD activity and hepatic HSP70 mRNA levels within 24 h after the initiation of crowding stress. However, decreases relative to the control were observed in the serum cortisol and glucose contents in the three treatment groups at 12 and 24 h after the initiation of crowding stress, in ALT and AST activity in the astaxanthin and emodin group at 24 h after the initiation of crowding stress, and in the serum lysozyme activity, serum alkaline phosphatase (ALP) activity, and hepatic catalase (CAT) and malondialdehyde (MDA) activity in the combination group at 24 h after the initiation of crowding stress. Additionally, the cumulative mortality after P. mirabilis infection was lower in all three treatment groups (57.00%-70.33%) than in the control (77.67%). Dietary supplementation with astaxanthin and emodin decreased the specific growth rate (SGR) and weight gain (WG) of healthy yellow catfish, although significant differences in mortality were not observed. These results indicate that dietary supplementation with 80 mg/kg astaxanthin and 150 mg/kg emodin can improve the anti-oxidative capabilities, hepatic HSP70 levels, and resistance to acute crowding stress of yellow catfish. Finally, an appropriate strategy for enhance yellow catfish stress resistance and disease resistance is proposed.

GlpC gene is responsible for biofilm formation and defense against phagocytes and imparts tolerance to pH and organic solvents in Proteus vulgaris.

Biofilm-forming bacteria are highly resistant to antibiotics, host immune defenses, and other external conditions. The formation of biofilms plays a key role in colonization and infection. To explore the mechanism of biofilm formation, mutant strains of Proteus vulgaris XC 2 were generated by Tn5 random transposon insertion. Only one biofilm defective bacterial species was identified from among 500 mutants. Inactivation of the glpC gene coding an anaerobic glycerol-3-phosphate dehydrogenase subunit C was identified by sequence analysis of the biofilm defective strain. Differences were detected in the growth phenotypes of the wild-type and mutant strains under pH, antibiotic, and organic solvent stress conditions. Furthermore, we observed an increase in the phagocytosis of the biofilm defective strain by the mouse macrophage RAW264.7 cell line compared to the wild-type strain. This study shows that the glpC gene plays an important role in biofilm formation, in addition to imparting pH, organic solvent, and antibiotic tolerance, and defense against phagocytosis to Proteus sp. The results further clarified the mechanism of biofilm formation at the genomic level, and indicated the importance of the glpC gene in this process. This data may provide innovative therapeutic measures against P. vulgaris infections; furthermore, as an important crocodile pathogen, this study also has important significance in the protection of Chinese alligators.

Survey of multidrug resistance integrative mobilizable elements SGI1 and PGI1 in Proteus mirabilis in humans and dogs in France, 2010-13.

OBJECTIVES: To characterize MDR genomic islands related to Salmonella genomic island 1 (SGI1) and Proteus genomic island 1 (PGI1) in Proteus mirabilis from human and animal sources in France in light of the previously reported cases. METHODS: A total of 52 and 46 P. mirabilis clinical strains from human and animal sources, respectively, were studied for the period 2010-13. MDR was assessed by antimicrobial susceptibility testing, PCR detection of SGI1 and PGI1 and PCR mapping of the MDR regions. The diversity of the SGI1/PGI1-positive P. mirabilis strains was assessed by PFGE. RESULTS: Twelve P. mirabilis strains (5 humans and 7 dogs) were found to harbour an MDR island related to SGI1 or PGI1. Among them, several SGI1 variants were identified in diverse P. mirabilis genetic backgrounds. The variant SGI1-V, which harbours the ESBL bla VEB-6 gene, was found in closely genetically related human and dog P. mirabilis strains. The recently described PGI1 element was also identified in human and dog strains. Finally, one strain harboured a novel SGI genomic island closely related to SGI1 and SGI2 without an insertion of the MDR region. CONCLUSION: This study reports for the first time, to our knowledge, SGI1-positive and PGI1-positive P. mirabilis strains from dogs in France. The genetic diversity of the strains suggests several independent horizontal acquisitions of these MDR elements. The potential transmission of SGI1/PGI1-positive P. mirabilis strains between animals and humans is of public health concern, notably with regard to the spread of ESBL and carbapenemase genes, i.e. bla VEB-6 and bla NDM-1.

Phenotypic and molecular characterization of antimicrobial resistance in Proteus mirabilis isolates from dogs.

Large-scale monitoring of resistance to 14 antimicrobial agents was performed using 103 Proteus mirabilis strains isolated from dogs in Japan. Resistant strains were analysed to identify their resistance mechanisms. Rates of resistance to chloramphenicol, streptomycin, enrofloxacin, trimethoprim/sulfamethoxazole, kanamycin, ampicillin, ciprofloxacin, cephalothin, gentamicin, cefoxitin and cefotaxime were 20.4, 15.5, 12.6, 10.7, 9.7, 8.7, 5.8, 2.9, 2.9, 1.9 and 1.9%, respectively. No resistance to ceftazidime, aztreonam or imipenem was found. Class 1 and 2 integrases were detected in 2.9 and 11.7% of isolates, respectively. Class 1 integrons contained aadB or aadB-catB-like-blaOXA10-aadA1, whereas those of class 2 contained sat-aadA1, dhfr1-sat-aadA1 or none of the anticipated resistance genes. Of five distinct plasmid-mediated quinolone-resistance (PMQR) genes, only qnrD gene was detected in 1.9% of isolates. Quinolone-resistance determining regions (QRDRs) of gyrA and parC from 13 enrofloxacin-intermediate and -resistant isolates were sequenced. Seven strains had double mutations and three had single mutations. Three of nine ampicillin-resistant isolates harboured AmpC-type ß-lactamases (i.e. blaCMY-2, blaCMY-4 and blaDHA-1). These results suggest that canine Proteus mirabilis deserves continued surveillance as an important reservoir of antimicrobial resistance determinants. This is the first report, to our knowledge, describing integrons, PMQRs and QRDR mutations in Proteus mirabilis isolates from companion animals.

Mucus accumulation and necrosis of the ventral air pouch in a marabou stork (Leptoptilos crumeniferus) with productive rhinitis.

A captive-born marabou stork (Leptoptilos crumeniferus) was presented for swelling of the ventral air pouch of 1 month's duration. The pouch appeared fluid filled, and its distal third wall was markedly inspissated. The thickened distal portion of the pouch wall was removed surgically. During anesthesia, mucous discharge from the nares was evident and the nasal mucosa was hyperemic. Aeromonas and Proteus species were isolated from a nasal culture. Postoperative therapy that consisted of nasal flushing, antimicrobial agents, and nonsteroidal anti-inflammatory drugs was effective in managing the disease. On histologic examination, diffuse hemorrhage, necrosis, and multifocal vasculitis with moderate-to-severe heterophilic inflammation were present within sections of the ventral pouch. To our knowledge this is the first report of a mucus-filled ventral air pouch with associated pathologic changes secondary to a productive infection of the upper respiratory tract in a marabou stork. The unique communication between nasal cavities and the ventral air pouch should be considered in future cases of respiratory infection in marabou storks.