P2241 - Clinical Remission in Collagenous Colitis Following Antibiotic Treatment in Seven Patients

Anoja W. Gunaratne, PhD, MSc, Annabel K. Clancy, PhD, Harrison Hamblin, BSc, Robert L. Clancy, PhD, DSc, Thomas J. Borody, PhD, DSc
Centre for Digestive Diseases, Five Dock, New South Wales, Australia

Introduction: Collagenous Colitis (CC) is a subtype of microscopic colitis, which presents with chronic, non-bloody, watery diarrhoea > 3 stools/d. Onset is often gradual, but may be sudden in approximately 40% of patients accompanied by urgency (70%), incontinence (40%), nocturnal episodes (50%), weight loss and abdominal pain. The colon is unremarkable macroscopically with histological changes of microscopic colitis and a thickened collagen layer. Causes of CC remain unknown, however autoimmunity, non-steroidal anti-inflammatory drugs, genetic predisposition and post gastrointestinal infection changes are hypothesised. No curative treatments are available for CC, with treatment focusing on short-term symptomatic relief. In our clinic, we have routinely used antibiotic (ABX) combinations to treat CC patients who had failed prior anti-diarrhoeal, anti-inflammatory or immunosuppressive therapy after we observed a marked improvement in one patient prescribed oral vancomycin. The aim of this review was to assess clinical outcomes of consecutive patients with CC, treated with ABX combinations.

Methods: Medical records of patients diagnosed with CC, who were treated with ABX therapy between November 2008–May 2021, were reviewed. Clinical remission from CC was defined as < 3 stools/d and < 1 watery stool/d. Stool consistency was determined using the Bristol Stool Chart (BSC). Other clinical improvements such as incontinence, urgency and nocturnal diarrhoea were noted.

Results: Seven patients (mean age 70 years, 6 Females, 1 Male) with CC initially with > 6 watery stools/d, including nocturnal incontinence were treated with ABX (Table 1). Six patients used combined ABX including oral vancomycin, rifaximin, metronidazole or tinidazole, achieved clinical remission (< 3 formed stools/d) in 1-8 weeks after commencing treatment which continued for 10-144 months. Absence of associated urgency (75%), incontinence (100%) and overall improvement in Quality of Life (QoL) (100%) were reported. Continuation of the ABX regimes resulted in sustained periods of clinical remission.

Discussion: In this cohort, ABX therapy successfully induced clinical remission in patients with CC lasting for up to 144 months. All patients reported an enhanced QoL and continued to see improvement of symptoms with ongoing use of ABX treatment. Cessation of ABX treatment resulted in a relapse of symptoms consistent with CC, suggesting that CC may be caused by an occult microbiome infection.

Demographics	Pre-Treatment			Treatment		Short Term Treatment Outcomes*		Long Term Outcomes
Patient ID, Age, Gender	BM/Day, BSC Score	Symptoms	Duration of Symptoms (Yrs)	Antibiotic Combination	Duration (Mths)	BM/Day, BSC Score	Symptoms	Duration of Clinical Remission (Mths)
Pt. ID: #1 Age: 75 Gender: F	BM/Day: 6-8 BSC Score: 6-7	Urgency: Y Incontinence: Y	1	Rifaximin 500mgx bd Metronidazole 400mgxbd	84	BM/Day: 1-2 BSC Score: 5	Urgency: N Incontinence: N	84
Pt. ID: #2 Age: 70 Gender: F	BM/Day: 7-30 BSC Score: 7	Urgency: Y Incontinence: Y	11	Vancomycin 500mgx bd Tinidazole 250mgx bd	7	BM/Day: 2 BSC Score: 4-5	Urgency: N Incontinence: N	10
Pt. ID: #3 Age: 85 Gender: F	BM/Day: 12 BSC Score: 7	Urgency: Y Incontinence: Y	1	Vancomycin 250mgx qd Tinidazole 500mgx bd	36	BM/Day: 2 BSC Score: 5	Urgency: Y Incontinence: N	36
Pt. ID: #4 Age: 52 Gender: M	BM/Day: 7-10 BSC Score: 7	Urgency: Y Incontinence: Y	1	Vancomycin 750x bd Metronidazole 400x bd Rifampicin 150mgx bd	144	BM/Day: 1-2 BSC Score: 4	Urgency: N Incontinence: N	144
Pt. ID: #5 Age: 64 Gender: F	BM/Day: 9-10 BSC Score: 7	Urgency: Y Incontinence: Y	3	Vancomycin 500mgx bd	24	BM/Day: 3-4 BSC Score: 5	Urgency: N Incontinence: N	18
Pt. ID: #6 Age: 71 Gender: F	BM/Day: 10 BSC Score: 7	Urgency: Y Incontinence: Y	2	Rifaximin 500mgx bd Tinidazole 500mgx bd	24	BM/Day: 1-2 BSC Score: 4	Urgency: N Incontinence: N	24
Pt. ID: #7 Age: 73 Gender: F	BM/Day: 7-8 BSC Score: 7	Urgency: Y Incontinence: Y	1	Vancomycin 500mgx bd Rifaximin 500mgx bd	60	BM/Day: 2-3 BSC Score: 4	Urgency: N Incontinence: N	60

Table: Table 1: Characteristics of patients with collagenous colitis pre, during and post treatment with combination antibiotics

BM: Bowel Motions; BSC: Bristol Stool Chart; Mths: months; Yrs: Years; Y: yes; N: no; bd: twice a day; qd: once a day; *Assessed 1-8 weeks into abx treatment




Disclosures:
Anoja Gunaratne: Centre for Digestive Diseases – Employee.
Annabel Clancy: Centre for Digestive Diseases – Employee.
Harrison Hamblin: Centre for Digestive Diseases – Employee.
Robert Clancy: Centre for Digestive Diseases – Consultant.
Thomas Borody: Centre for Digestive Diseases – Advisory Committee/Board Member, Consultant, Employee, Grant/Research Support, Patent Holder, Stockholder/Ownership Interest (excluding diversified mutual funds).


Anoja W. Gunaratne, PhD, MSc, Annabel K. Clancy, PhD, Harrison Hamblin, BSc, Robert L. Clancy, PhD, DSc, Thomas J. Borody, PhD, DSc. P2241 - Clinical Remission in Collagenous Colitis Following Antibiotic Treatment in Seven Patients, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.