Medical Science
Volume 24, Issue 104, July - August, 2020
Prevalence and predictive factors of microscopic colitis in patients with chronic watery non-bloody diarrhea: A tertiary center study
Samar K. Darweesh1, Iman M. Hamza1, Mahmoud M. Abouelkhair1, Ahmed N. Eesa2, Abdulbaset A. Moqbel1,3♦
1Hepatogastroenetrology and Endemic Medicine, Cairo University, Cairo, Egypt
2Pathology Department, Cairo University, Cairo, Egypt
3Department of Internal Medicine, Thamar University, Thamar, Yemen
♦Corresponding author
Hepatogastroenetrology and Endemic Medicine, Cairo University, Cairo, Egypt;
Email: alkhamery@yahoo.com
ABSTRACT
Microscopic colitis (MC) is increasingly recognized during colonoscopy and biopsy of normal mucosa in chronic watery non-bloody
diarrhea (CWND) patients. The prevalence and predictive factors of MC among CWND patients with normal colonoscopy were
investigated in this study. 194 patients with CWND of unknown etiology in the period from March 2017 to June 2018 underwent full
colonoscopy and biopsy. A total of 88 with normal colonoscopic findings were enrolled in this study and pathology results analyzed.
The study showed that 8/88 (9.1%) patients with CWND and normal colonoscopy had MC; all of MC patients had lymphocytic colitis
(100%). Predictive factors for MC were the age ≥50 years, frequent diarrhea>7 motions/day, duration of diarrhea ≤6 months,
nocturnal diarrhea, abdominal pain, weight loss, current use of PPI and/or H2 receptors blockers and low serum Na and/or K level.
We have created a diagnostic scoring system for the prediction of MC, with ranging scores from –1 to +10. A cutoff value >3
recognized MC patients with 100% sensitivity and 91% specificity (AUC, 0.99). With scores ˃5 and ˃6, specificity increased to 97%
and 100% while the sensitivity decreased to 75% and 62% respectively (AUC, 0.99). Hence, this study concluded that MC is not
uncommon in CWND patients and normal colonoscopic findings. A biopsy of normal colonic mucosa is emphasized to reach the
definite diagnosis of MC. However, the created scoring system can identify MC patients and lower costs by recognizing unlikely MC
patients.
Keywords: Microscopic colitis, lymphocytic colitis, chronic watery diarrhea, predictive factors, scoring system
Medical Science, 2020, 24(104), 2137-2146
