Pet-related bacterial zoonotic infections: Three cases of severe infections in the immunocompromised host.

Pets can have many positive effects on their owners. However, close contact with pets offers optimal conditions for transmission of micro-organisms. Especially immunocompromised patients are at risk for zoonotic infections. Here we describe the diagnosis, microbiology and treatment of three patients with severe zoonotic infections with Helicobacter canis, Pasteurella multocida and Capnocytophaga canimorsus. With this case report we would like to emphasize the importance of awareness for pet-related zoonotic infections in immunocompromised patients.

Helicobacter canis bacteraemia in a rheumatoid arthritis patient treated with tofacitinib: case report and literature review.

BACKGROUND: Non-Helicobacter pylori species (NHPS) are newly emerging bacteria that naturally inhabit birds and mammals apart from humans and rarely cause diseases in humans. In recent years, a rise in the number of cases associated with NHPS infections in humans has been observed. Among them, infections with Helicobacter (H.) canis are sporadic and challenging to recognise clinically. To date, ten cases of H. canis infections in mainly immunocompromised humans have been reported in the literature. Transmission pathway is most likely zoonotic via the faecal-oral route during close contacts with dogs and cats or may result from a contaminated sheep milk intake. No clear guidelines for successful antibiotic regimen are known. Important additional risk factor for infection might be biologic agents and Janus kinase inhibitors (JAKi) used in the treatment of rheumatoid arthritis (RA) and other conditions. Herein we present the first case of H. canis bacteraemia in a RA patient treated with novel JAKi tofacitinib. CASE PRESENTATION: A 65-year-old female patient with RA and rituximab-induced hypogammaglobulinemia treated with tofacitinib, methotrexate, and methylprednisolone came to a planned visit in our outpatient rheumatology clinic. She presented with a history of back pain that significantly worsened 2 days before visit. She had numbness and tingling sensation in both legs and muscle weakness. Neurological examination was within a normal range. The patient was afebrile, had no chills, and was haemodynamically stable. She was in close contact with her pet dogs. Laboratory examination showed increased markers of inflammation. She was found to have H. canis bacteraemia with underlying multilevel degenerative lumbar spinal stenosis. Identification of H. canis was performed by MALDI-TOF MS and 16 S rRNA gene sequence analysis of isolate from subcultured positive aerobic blood culture bottles. Antimicrobial susceptibility testing showed low minimum inhibitory concentrations to amoxicillin-clavulanate, cefotaxime, ceftriaxone, meropenem, and gentamicin. She was treated with combined antibiotic regimen (ceftriaxone, doxycycline) for 14 days, which resulted in total remission of the infection. CONCLUSIONS: Clinicians should recognise H. canis infection risk in patients with recent pet exposure and predisposing factors such as immunodeficiency disorders or diseases that demand immunosuppressive drug therapy. A minimum of two weeks of antibiotic therapy is suggested.

Helicobacter canis: A Review of Microbiological and Clinical Features.

Helicobacter canis, an enterohepatic Helicobacter, has proven its role in human diseases and has been rediscussed in recent years as its zoonotic potential is increasingly described. Routine microbiological detection of this pathogen is a difficult task as its culture may fail due to fastidious growth. It is therefore supposed that many clinical laboratories under-recognize H. canis infections. A review of all clinical and microbiological literature currently available from previous relevant H. canis human clinical cases, mainly bacteremia, added with a clinical case observed at the Cliniques universitaires Saint-Luc, was performed. Clinical features of H. canis reports show the presence of underlying clinical conditions in 89% of the cases, bacteremia in 83%, associated fever in 58%, and recent close contact with pets in 83%, especially dogs. The observed microbiological trends from 10 cases of bacteremia were a median of 4 days until positive blood culture bottle detection, subcultures showing a thin layer of small colonies under microaerophilic atmosphere at 35-42°C after 3-4 days of growth, and an identification requiring 16S rRNA sequencing given the difficulties observed with MALDI-TOF MS. Low MICs were observed for penicillins, amoxicillin/clavulanic acid, carbapenems, and metronidazole in opposition to high MICs for ciprofloxacin. A frequent association of H. canis and bacteremia in immunocompromised patients with recurrent fever in contact with pets, especially dogs, was identified. Considering the fastidious growing capacities, final identification from blood cultures may not be expected before 7 days. Intravenous ceftriaxone, oral doxycycline, or metronidazole has been suggested as efficient therapeutic choices.

Helicobacter genus in the intestine and liver of stray cats: the molecular, histopathological, and immunohistochemical study.

OBJECTIVES: The study was designed to determine the presence of Helicobacter genus and three species of H. pylori, H. bilis, and H. canis, in the duodenum, ileum, colon, and liver of stray cats. Moreover, the histopathological and immunohistochemical analyses have been performed. METHODS: Samples were taken from the duodenum, ileum, colon, and liver of 30 cats for molecular and histopathological evaluations. Polymerase chain reaction was carried out for the detection of the Helicobacter genus in the mentioned samples. Then, species-specific primers were used in Helicobacter-positive samples. RESULTS: Helicobacter genus prevalence rates in the duodenum, ileum, colon, and liver samples were 50%, 60%, 50%, and 43.3%, respectively. Helicobacter pylori, H. canis, and H. bilis were isolated from at least one tissue of 18 (60%), 13 (43.3%), and 8 (26.7%) of the cats, respectively. Immunohistochemical findings confirmed the presence of bacteria in the intestinal crypt or the mucosal layer of duodenum, ileum, colon, and hepatic sinusoids. CONCLUSION: In the present study, the concurrent infection of duodenum and liver was noticeable. Furthermore, the high prevalence of H. pylori in cats, as a well-known human pathogen, should be considered. High incidence of Helicobacter in gut and liver of Ahvaz stray cats is noticeable. According to the zoonotic importance of Helicobacter, more studies in the field of treatment and prevention are highly recommended.

Helicobacter canis bacteraemia and cellulitis in a patient with end-stage renal disease.

Introduction. Invasive infections by Helicobacter canis are uncommon and occur primarily in immunocompromised patients. Here, we describe a case of H. canis bacteraemia and cellulitis in a patient with end-stage renal disease (ESRD). Case presentation. A 49-year-old male with ESRD on haemodialysis presented to an emergency department with cellulitis overlying his left upper extremity arteriovenous fistula for 3 days without constitutional symptoms. Mild leucocytosis and thrombocytopenia was noted on initial laboratory work up. The patient received a dose of vancomycin initially, and then transitioned to oral doxycycline prior to discharge 3 days later. Blood cultures drawn on admission were positive with curved Gram-negative rods at day 5. Routine sub-cultures initially failed to isolate the organism; however, small, tan colonies were observed on sheep blood agar incubated under microaerobic conditions. H. canis was identified by 16S rRNA sequencing. Antimicrobial-susceptibility testing was not performed due to poor growth and lack of interpretive guidelines. The patient was ultimately treated successfully with amoxicillin/clavulanic acid. Conclusion. This case illustrates the importance of recognizing H. canis infections in immunocompromised patients, especially in those with recent pet exposure. In addition, this case highlights the need for improved laboratory diagnostics for H. canis as isolation and identification of this fastidious organism is challenging.

Evidence of Zoonotic Transmission of Helicobacter canis Between Sheep and Human Contacts.

Helicobacter species are newly emerging bacteria with great public implications but till now its epidemiology is not fully understood; so, this study was conducted to investigate the possible role of ruminants in the epidemiology of these pathogens. For this purpose, fecal samples were collected from 149 animals (76 sheep, 33 goats, 21 cattle, and 19 buffaloes) and stool specimens from 10 animal caretakers in intimate contact with the examined animals. All samples were examined for the presence of Helicobacter species through detection of Helicobacter genus specific 16S rRNA using PCR. Then, all positive Helicobacter spp. amplicons were sequenced to recognize their species through BLAST analysis at GenBank. The overall prevalence of Helicobacter spp. was 14.8% while the distribution among the different animals was 26.3%, 3%, 4.8%, and 0% in sheep, goats, cattle, and buffaloes respectively. Helicobacter canis was the predominant species and detected only in sheep (21%) and goats (3%). Moreover, Helicobacter winghamensis and Helicobacter canadensis were also detected in sheep but not in other animals, whereas the only positive bovine sample was identified as Helicobacter bovis. On the other hand, 4 out of 10 humans were positive for Helicobacter spp. and all sequences were identified as H. canis. The sequences identity matrix and phylogenetic analysis of H. canis sequences from humans and sheep contacts revealed that one human sequence was identical to that of sheep and making sister group clade, which prove the zoonotic transmission of this pathogen between sheep and human contacts. However, our findings highlight sheep as a potential reservoir for H. canis, further researches are needed to address the potential role of sheep in the food-borne transmission of such emerging pathogen.

Helicobacter canis bacteremia in a renal transplant patient.

Here we present a case report of a 41-year-old woman suffering from high fever and bacteremia due to Helicobacter canis, 11 months after kidney transplantation. Identification of H. canis was achieved by 16s rDNA sequence analysis of a positive blood culture. The patient was restored fully to health after antibiotics therapy (cefuroxime and ciprofloxacin). Until now, only 4 human clinical cases have been described with H. canis bacteremia. This study describes for the first time, to our knowledge, an infection with H. canis in a kidney transplant patient.