Severe Colitis with Portal Venous Gas Caused by Brachyspira pilosicoli Infection

Clinical and Pathologic Factors Associated With Colonic Spirochete (Brachyspira pilosicoli and Brachyspira aalborgi) Infection: A Comprehensive Systematic Review and Pooled Analysis

OBJECTIVES

This study aims to determine what pathologic and clinical factors differentiate Brachyspira species that may be useful to clinicians and pathologists.

METHODS

We identified 21 studies of Brachyspira infection with individual patient information (n = 113) and conducted a pooled analysis comparing each species.

RESULTS

There were differences in the pathologic and clinical profiles of each Brachyspira species. Patients infected with Brachyspira pilosicoli infection were more likely to have diarrhea, fever, HIV, and immunocompromised conditions. Those patients infected with Brachyspira aalborgi were more likely to have lamina propria inflammation.

CONCLUSIONS

Our novel data provide potential insights into the pathogenic mechanism(s) and the specific risk factor profile of Brachyspira species. This may be clinically useful when assessing and managing patients.

Human intestinal spirochetosis, a sexually transmissible infection? Review of six cases from two sexually transmitted infection centres in Barcelona

Human intestinal spirochetosis (HIS) is a possible cause of chronic diarrhoea and affects mainly men who have sex with men (MSM) and people living with HIV. Diagnosis is based on colon biopsy, where spirochetes can be observed on the luminal surface, especially with the Warthin-Starry stain or similar silver stains. We conducted a retrospective descriptive study of all HIS cases diagnosed in two sexually transmitted infections (STI) centres in Barcelona from 2009 until 2018. The medical histories were reviewed to gather epidemiological, clinical, and diagnostic variables. Six patients were diagnosed with HIS. All the individuals were MSM, with a median age of 31.5 years (interquartile range [IQR] 29.5;49.25) and half of them were living with HIV. Five patients reported condomless anal intercourse and 4 patients had practised oro-anal sex previously. Concomitantly, two of them had rectal gonorrhoea, one had rectal Chlamydia trachomatis and none of them had syphilis. The predominant clinical symptom was diarrhoea (5 patients). All cases were diagnosed by a Warthin-Starry stain on a colon biopsy specimen, and mild inflammatory changes were found in 5 cases. Five patients were treated with metronidazole and one with benzathine penicillin G. Treatment was successful in all the patients. HIS should be considered in patients with chronic diarrhoea who report risky sexual practices and/or concomitant STI. HIS may also be sexually transmitted according to the context.