The first case of Pasteurella canis bacteremia: a cirrhotic patient with an open leg wound

Biotypic and genotypic diversity in Pasteurella canis isolated from host animals and humans: differences in trehalose fermentation and nucleotide sequences encoding trehalose-6-phosphate hydrolase (treC)

The biotypic and genotypic features of Pasteurella canis isolated from dogs, cats, and humans were clarified by repetitive sequence-based fingerprinting and nucleotide sequences encoding trehalose-6-phosphate hydrolase (treC). Thirty P. canis and 48 P. multocida isolates were collected from dogs, cats, and humans to perform biotyping. The genotyping of P. canis by fingerprinting was followed by dendrogram construction. The whole-genome sequences (WGSs) were searched for the enzyme-coding nucleotide sequences around the main and adjacent loci constituting the operon. Full-length nucleotide sequences encoding the enzyme were determined using polymerase chain reaction and direct sequencing. Biotypic results were compared to the dendrogram and nucleotide sequence data. We observed a difference in trehalose fermentation with a positivity rate of 46.7%. Two (A-1/A-2) and three (B-1/B-2/B-3) clades were located on the dendrograms generated based on two repetitive sequence-based fingerprinting techniques, showing no association between trehalose fermentation and the clades. Based on the WGSs, two variants of the gene, namely, a 1,641 bp gene treC and a pseudogene (1,335 bp) of treC with its first 306 nucleotides deleted, were observed. Trehalose-positive isolates harbored treC, whereas trehalose-negative isolates lacked treC with or without the pseudogene. Our observations suggest biotypic and genotypic diversity among the P. canis isolates from animal and human hosts, with respect to trehalose fermentation and treC nucleotide sequences. This is the first report on the diversity of treC nucleotide sequences among these isolates.

Nanopore Sequencing Using the Full-Length 16S rRNA Gene for Detection of Blood-Borne Bacteria in Dogs Reveals a Novel Species of Hemotropic Mycoplasma

Dogs across the globe are afflicted by diverse blood- and vector-borne bacteria (VBB), many of which cause severe disease and can be fatal. Diagnosis of VBB infections can be challenging due to the low concentration of bacteria in the blood, the frequent occurrence of coinfections, and the wide range of known, emerging, and potentially novel VBB species encounterable. Therefore, there is a need for diagnostics that address these challenges by being both sensitive and capable of detecting all VBB simultaneously. We detail the first employment of a nanopore-based sequencing methodology conducted on the Oxford Nanopore Technologies (ONT) MinION device to accurately elucidate the "hemobacteriome" from canine blood through sequencing of the full-length 16S rRNA gene. We detected a diverse range of important canine VBB, including Ehrlichia canis, Anaplasma platys, Mycoplasma haemocanis, Bartonella clarridgeiae, "Candidatus Mycoplasma haematoparvum", a novel species of hemotropic mycoplasma, and Wolbachia endosymbionts of filarial worms, indicative of filariasis. Our nanopore-based protocol was equivalent in sensitivity to both quantitative PCR (qPCR) and Illumina sequencing when benchmarked against these methods, achieving high agreement as defined by the kappa statistics (k > 0.81) for three key VBB. Utilizing the ability of the ONT' MinION device to sequence long read lengths provides an excellent alternative diagnostic method by which the hemobacteriome can be accurately characterized to the species level in a way previously unachievable using short reads. We envision our method to be translatable to multiple contexts, such as the detection of VBB in other vertebrate hosts, including humans, while the small size of the MinION device is highly amenable to field use. IMPORTANCE Blood- and vector-borne bacteria (VBB) can cause severe pathology and even be lethal for dogs in many regions across the globe. Accurate characterization of all the bacterial pathogens infecting a canine host is critical, as coinfections are common and emerging and novel pathogens that may go undetected by traditional diagnostics frequently arise. Deep sequencing using devices from Oxford Nanopore Technologies (ONT) provides a solution, as the long read lengths achievable provide species-level taxonomic identification of pathogens that previous short-read technologies could not accomplish. We developed a protocol using ONT' MinION sequencer to accurately detect and classify a wide spectrum of VBB from canine blood at a sensitivity comparable to that of regularly used diagnostics, such as qPCR. This protocol demonstrates great potential for use in biosurveillance and biosecurity operations for the detection of VBB in a range of vertebrate hosts, while the MinION sequencer's portability allows this method to be used easily in the field.

Microbiological Survey of 47 Permanent Makeup Inks Available in the United States

In two previous surveys, the U.S. Food and Drug Administration (FDA) identified microbial contamination in 53 of 112 (47%) unopened tattoo inks and tattoo-ink-related products (e.g., diluents) from 15 manufacturers in the U.S. In this study, we primarily focused our microbiological survey on permanent makeup (PMU) inks. We conducted a survey of 47 unopened PMU inks from nine manufacturers and a comparative species-centric co-occurrence network (SCN) analysis using the survey results. Aerobic plate count and enrichment culture methods using the FDA's Bacteriological Analytical Manual (BAM) Chapter 23 revealed that 9 (19%) inks out of 47, from five manufacturers, were contaminated with microorganisms. The level of microbial contamination was less than 250 CFU/g in eight inks and 980 CFU/g in one ink. We identified 26 bacteria that belong to nine genera and 21 species, including some clinically relevant species, such as Alloiococcus otitis, Dermacoccus nishinomiyaensis, Kocuria rosea, and Pasteurella canis. Among the identified microorganisms, the SCN analysis revealed dominance and a strong co-occurrence relation of spore-forming extreme environment survivors, Bacillus spp., with close phylogenetic/phenotypic relationships. These results provide practical insights into the possible microbial contamination factors and positive selection pressure of PMU inks.

Septic Arthritis and Bacteremia Due to Infection by Pasteurella canis

Pasteurella canis is a Gram-negative coccobacilli from the Pasteurellaceae family. The most common form of transmission to humans is a bite from a dog or a cat. We report a case of a 90-year-old woman who presented with septic arthritis in the right knee and bacteremia two weeks after a cat bite. The patient was treated with arthrocentesis and directed antimicrobial therapy. Human Pasteurella canis infection is a rare occurrence, making this a case of note.

Pasteurella bacteraemia: Impact of comorbidities on outcome, based on a case series and literature review

OBJECTIVES

Pasteurella bacteraemia is rare, but has been associated with a high mortality rate. The aim of this study was to estimate the impact of comorbidities on patients with Pasteurella bacteraemia.

METHODS

All cases of Pasteurella bacteraemia in adults treated in our centre between January 2008 and December 2017 were included retrospectively and compared with cases identified in a systematic review of the literature via MEDLINE covering the years 1951-2017. The epidemiological, bacteriological, and clinical data were collected, as well as the instances of death after 30 days.

RESULTS

Twenty cases of Pasteurella bacteraemia identified in our centre and 99 cases from the literature review were included. A major comorbidity was found in 80/119 (67.2%) patients. The death rate at 30 days was 31.1%. The most common comorbidities were cirrhosis, immunosuppressive therapy, and malignant diseases. Age was not associated with mortality. On multivariate analysis, the only factor associated with mortality was a major comorbidity (odds ratio 2.78, 95% confidence interval 1.01-7.70; p = 0.04).

CONCLUSIONS

This study confirms the high mortality rate and highlights the importance of the host background, independent of age, in Pasteurella bacteraemia. Clinicians should be aware of the comorbidities in cases of Pasteurella infection, due to the poor prognosis of bacteraemia.

Pasteurella canis infective endocarditis in a dog

Infective endocarditis, an infrequent clinical syndrome in dogs, is typically associated with nondescript clinical signs such as fever, malaise and loss of appetite. Although an uncommonly reported infection in dogs, Pasteurella canis is an emerging pathogen with increasing relevance in the human microbiology literature. The goal of this study is to detail the clinical presentation and microbiological findings associated with a novel causative agent of infective endocarditis in the dog. Diagnostic evaluation as well as conventional, automated and molecular microbiological methods are highlighted. The recent literature regarding P. canis and infective endocarditis in companion animals and humans is reviewed. Although an unusual etiologic agent of infective endocarditis, awareness of P. canis as a diagnostic possibility is crucial to accurate microbial surveillance.

Medical and surgical management of Pasteurella canis infectious keratitis

Introduction

We describe a case of refractory Pasteurella Canis keratitis that initially failed antimicrobial treatment but was successfully treated with a conjunctival flap followed by a penetrating keratoplasty.

Case discussion

A 70-year-old male had persistent corneal edema related to previous herpes zoster keratouveitis with visual acuity of 20/400. An endothelial keratoplasty was performed with improvement in vision to 20/25. Several months after this surgery the patient developed a corneal infiltrate and cultures grew Pasturella canis. The infection persisted despite topical treatment with broad spectrum fortified vancomycin, tobramycin and fluoroquinolones. A conjunctival flap combined with corneal cryotherapy was performed to help mitigate symptoms and to allow the ulcer to heal. A penetrating keratoplasty was done several months later.

Discussion

The patient achieved pain relief immediately after the flap was placed. Medications were tapered off in the following few months after the procedure. A penetrating keratoplasty was performed 4 months later. The patient has remained almost entirely symptom free, and the graft remained clear one year after surgery.

Conclusions

A keratitis caused by Pasteurella canis that is resistant to medical therapy can be treated successfully with a conjunctival flap and cryotherapy followed by a penetrating keratoplasty.

Unusual Aetiology of Pasteurella canis Biovar 2 Causing Dacryocystitis in HIV Patient: A Case Report and Review of Literature

Pasteurella species are zoonotic bacterial pathogens implicated very infrequently in various human infections following animal bites or licks usually of dogs and cats. This case report described a rare clinical presentation of dacryocystitis caused by P.canis in a Human Immunodeficiency Virus (HIV) positive young male patient involved in caring of cattle. It advocates the utmost need of recognizing the wide clinical manifestation spectrum of P.canis even without prior penetrating injury. P.canis associated clinical infection is more extensive than had been thought previously especially in immunocompromised patient. Early accurate identification and evidence based anti-microbial therapy may prove crucial in preventing further potential complications.

A Case of Lower Respiratory Tract Infection with Canine-associated Pasteurella canis in a Patient with Chronic Obstructive Pulmonary Disease

This is the report of lower respiratory tract infection with Pasteurella canis in a chronic obstructive pulmonary disease (COPD) patient with history of casual exposure to cats. Pasteurella species are part of the oral and gastrointestinal flora in the canine animals. These organisms are usually implicated in wound infection following animal bites, but can also be associated with a variety of infections including respiratory tract infections.

Deep sternal wound infection due to Pasteurella multocida: the first case report and review of literature

Pasteurella multocida is a Gram-negative bacterium recovered from a wide variety of wild and domestic animals and has mostly been associated with infection following animal bites. We present the first reported case of a patient who developed a postoperative sternal wound infection due to P. multocida complicated by bloodstream infection. The outcome was favorable following surgical debridement and antimicrobial therapy. We also review the literature regarding P. multocida postoperative wound infections.