#9: Diagnosis of Campylobacter upsaliensis and Helicobacter canis by plasma-based Next-Generation Sequencing for Microbial Cell-free DNA in twin brothers with XLA

Background X-linked agammaglobulinemia is a primary immunodeficiency associated with mutations in the B cell tyrosine kinase (BTK) gene leading to failure in B cell maturation and defective antibody production. Campylobacter and closely related Helicobacter species can cause persistent bacteremia, enteritis and cellulitis in patients with XLA and are difficult to diagnose and eradicate. In this context, detection of circulating microbial cell-free DNA (mcfDNA) by next-generation sequencing (NGS) can be used to identify infectious agents in susceptible immunocompromised hosts. Methods We report 4-year-old fraternal twins with XLA presenting with disparate clinical manifestations due to C. upsaliensis and coinfection with C. upsaliensis and H. canis respectively. Results Patient #1 was diagnosed with XLA at 11 months-old and was started on weekly immunoglobulin replacement. At 2.5 yo he developed recurrent fever, abdominal pain and diarrhea. Endoscopy/colonoscopy revealed focal ileocolitis without ulceration or granulomas. Stool infectious workup, including bacterial stool cultures, was negative. At 3 yo he developed gram- rod bacteremia that was not further identified but successfully treated with ceftriaxone. He presented 2 months later with fever and diarrhea; blood cultures were negative, but stool culture grew C. jejuni. His symptoms recrudesced after two months and he was treated for presumed recurrent Campylobacter infection. Intermittent fevers and diarrhea recurred, and repeat stool culture grew C. upsaliensis identified by MALDI-TOF resulting in a 3-month course of azithromycin. Stool PCR remained positive for Campylobacter species after one month of therapy. Fever and diarrhea recurred after completion of therapy and stool culture again grew C. upsaliensis but sensitivities could not be obtained. McfDNA testing confirmed C. upsaliensis and therapy with ertapenem, ciprofloxacin, amoxicillin and doxycycline was initiated. He remained symptom free three months into therapy. Patient #2 was diagnosed with XLA at 1 yo and started weekly immunoglobulin replacement. At 3.5 yo he developed fever, erythema nodosum (EN) and arthritis. Given his twin’s diagnosis of Campylobacter enteritis with likely bacteremia, a presumptive diagnosis of Campylobacter related reactive arthritis and EN was made. Treatment with Naprosyn and 14 days of azithromycin failed to prevent the return of EN post therapy. He had multiple courses of azithromycin each followed by return of EN rash. Following completion of therapy, he presented with high fevers, worsening rash, leukocytosis and elevated ESR. Blood and stool cultures were obtained and returned negative. Despite completion of a 3 month course of azithromycin, stool PCR remained positive for Campylobacter species and his symptoms persisted. The recrudescence of fevers and worsening rash 2 months after completion of therapy prompted repeat blood and stool cultures that returned negative. McfDNA testing was obtained in that context and identified Helicobacter canis and Campylobacter upsaliensis. Treatment with ertapenem, ciprofloxacin, amoxicillin and doxycycline was initiated and he remained symptom free three months into therapy. Conclusions Physicians should be aware of the varied presentations of chronic Campylobacter and Helicobacter infection in XLA patients. Plasma NGS for circulating mcfDNA in immunocompromised patients offers a rapid, non-invasive means of detecting these fastidious organisms that can be difficult to diagnose using more conventional means.

Prevalence and risk factors associated with Campylobacter spp. occurrence in healthy dogs visiting four rural community veterinary clinics in South Africa

Reports on the occurrence of Campylobacter spp. in dogs in South Africa are non-existent. This study investigated the prevalence of Campylobacter spp. in 481 dogs visiting four rural community veterinary clinics in South Africa. Dogs were screened for Campylobacter spp. by culture and polymerase chain reaction (PCR), and logistic regression analysis was performed to assess the association between sex, clinic, breed and age and the occurrence of Campylobacter spp. in dogs. The prevalence of Campylobacter spp. was 41.50% (95% confidence interval [CI], 37.39% – 46.04%). Campylobacter jejuni, C. upsaliensis and C. coli were detected in 29.31% (95% CI, 25.42% – 33.54%), 13.10% (95% CI, 10.37% – 16.42%) and 5.41% (95% CI, 3.71% – 7.82%) of dogs, respectively. Dogs carrying more than one species of Campylobacter spp. accounted for 6.23% (95% CI, 4.40% – 8.78%). Campylobacter upsaliensis and C. jejuni were detected in 3.74% (95% CI, 2.37% – 5.86%), whereas C. coli and C. jejuni were found in 2.49% (95% CI, 1.42% – 4.34%) of dogs. Age and clinic were the risk factors significantly associated with Campylobacter spp. occurrence, while age, breed and clinic were predictors of C. jejuni carriage. Furthermore, age was the only risk factor associated with a higher likelihood of carrying C. upsaliensis. The prevalence of Campylobacter spp. C. jejuni and C. upsaliensis increased significantly as dogs grew older. In addition, the odds of carrying Campylobacter spp. were higher in the Staffordshire bull terrier breed compared to crossbreed dogs. In conclusion, this study shows that dogs visiting rural community veterinary clinics in South Africa are reservoirs of Campylobacter spp. and may be potential sources of Campylobacter spp. for humans living in close proximity of the dog populations under study.

The role of Campylobacter spp. in chronic enteropathy in dogs

The aim of the study was to identify Campylobacter species in a group of patients with chronic gastrointestinal problems and to investigate the relationship between the presence of Campylobacter spp. in stool samples and as well as the severity of chronic enteropathy. Twenty-six dogs with chronic gastrointestinal problems were included in the prospective study. Each research subject had their stomach, duodenum, ileum, and colon examined endoscopically. A histopathological examination of the obtained biopsy samples was then performed, excluding other potential diseases. Stool samples were collected and then examined for the presence of Campylobacter spp. To evaluate the relationship between Campylobacter spp. occurrence and the intensity of chronic enteropathy, patients were divided into two groups; animals in the first group presented with no to mild inflammation whereas research subjects in the second group suffered from moderate to severe inflammation. Subsequently, the patients were divided based on positive or negative test results for Campylobacter spp. cultures. No significant relationship between the presence of Campylobacter spp. in stool samples and chronic enteropathy was found. In contrast to other previously published papers, our study showed a lower occurrence of Campylobacter upsaliensis.

Features of illnesses caused by five species ofCampylobacter, Foodborne Diseases Active Surveillance Network (FoodNet) – 2010–2015

SUMMARYThe Foodborne Diseases Active Surveillance Network (FoodNet) conducts population-based surveillance forCampylobacterinfection. For 2010 through 2015, we compared patients withCampylobacter jejuniwith patients with infections caused by otherCampylobacterspecies.Campylobacter colipatients were more often >40 years of age (OR = 1·4), Asian (OR = 2·3), or Black (OR = 1·7), and more likely to live in an urban area (OR = 1·2), report international travel (OR = 1·5), and have infection in autumn or winter (OR = 1·2).Campylobacter upsaliensispatients were more likely female (OR = 1·6), Hispanic (OR = 1·6), have a blood isolate (OR = 2·8), and have an infection in autumn or winter (OR = 1·7).Campylobacter laripatients were more likely to be >40 years of age (OR = 2·9) and have an infection in autumn or winter (OR = 1·7).Campylobacter fetuspatients were more likely male (OR = 3·1), hospitalized (OR = 3·5), and have a blood isolate (OR = 44·1). International travel was associated with antimicrobial-resistantC. jejuni(OR = 12·5) andC. coli(OR = 12) infections. Species-level data are useful in understanding epidemiology, sources, and resistance of infections.