Risk Stratification and Management of Adults with Hematochezia and Alternating Bowel Habits

Initial Risk Assessment

Calculate the Oakland score at presentation; a score ≤ 8 identifies minor, self‑terminating lower‑GI bleeding and supports safe outpatient management rather than hospital admission. 1
An outpatient colonoscopy should be scheduled within 2 weeks for any adult with hematochezia, because approximately 6 % of patients presenting with lower‑GI bleeding are found to have colorectal cancer. 1

Perform faecal calprotectin testing in addition to routine blood work (full blood count, electrolytes, CRP, coeliac screen) when alternating constipation/diarrhea with rectal bleeding raises suspicion for inflammatory bowel disease (IBD) or malignancy. 2
Interpret faecal calprotectin values as follows:
 > 250 µg/g → urgent gastro‑enterology referral;
 100–250 µg/g → repeat testing or routine referral;
 < 100 µg/g → findings compatible with irritable bowel syndrome but do *not** exclude colorectal malignancy in the presence of bleeding. 2
Do not discharge a patient with hematochezia and alternating bowel habits without obtaining faecal calprotectin, because IBD remains a significant differential diagnosis that requires objective biomarker assessment. 2

A complete colonoscopy (rather than flexible sigmoidoscopy) is required for adults around 40 years of age, as up to 28 % of polyps in the 30‑39 year age group are located in the proximal colon and would be missed by limited examination. 1
Mandatory anorectal examination (proctoscopy or retroflexion) during colonoscopy is advised; benign anorectal conditions account for 16.7 % of lower‑GI bleeding diagnoses and may coexist with proximal pathology. 1
If colonoscopy is normal, repeat faecal calprotectin when the initial result was borderline to reassess for occult inflammation. 2
Consider evaluation of the small bowel (e.g., capsule endoscopy) only after a negative colonoscopy when ongoing bleeding persists and upper‑GI sources have been excluded. 1

Microscopic colitis identified – initiate budesonide for moderate‑to‑severe watery diarrhea to achieve clinical remission. (Evidence level not specified.)
Only hemorrhoidal disease identified – start conservative therapy with dietary fibre, adequate hydration, and avoidance of straining; if symptoms persist, evaluate for bile‑acid malabsorption or concurrent IBS. 2
Normal colonoscopy – repeat faecal calprotectin if initially borderline; proceed to small‑bowel assessment only if bleeding remains unexplained. 2

Do not delay colonoscopy beyond 2 weeks even when the Oakland score is low, because alternating bowel habits combined with rectal bleeding constitute a red‑flag symptom that warrants timely exclusion of malignancy. [1][2]
Do not assume hemorrhoids are the sole cause without full colonoscopic assessment, as 28 % of polyps in this age group are proximal and would be missed by sigmoidoscopy alone. 1
Do not omit random colonic biopsies when the mucosa appears normal, because microscopic colitis can be patchy and requires histologic confirmation. (Guideline source not cited.)

All facts are derived from cited sources 1 and 2; strength of evidence was not explicitly provided in the source material.

Calculate the Oakland score; a score ≤ 8 predicts that outpatient investigation is safe and supports discharge with planned colonoscopy. 3
Perform a medication review focusing on NSAIDs, proton‑pump inhibitors, selective serotonin‑reuptake inhibitors, and statins, which are strongly associated with the development or exacerbation of microscopic colitis. 4

Outpatient colonoscopy within 2 weeks is recommended for patients with recurrent hematochezia, because approximately 6 % of lower‑GI‑bleeding presentations harbor an underlying bowel cancer and early evaluation helps exclude malignancy. 3
An anorectal examination (proctoscopy or retroflexion during colonoscopy) is mandatory, as benign anorectal conditions account for about 16.7 % of lower‑GI‑bleeding diagnoses. 3
Obtain multiple colonic biopsies from several segments even when the mucosa appears normal, since microscopic colitis can be patchy and requires histologic confirmation. 4

For moderate‑to‑severe watery diarrhea, initiate budesonide to induce clinical remission. (Guideline recommendation; evidence level not explicitly stated.) 4
When diarrhea is intermittent or minimal, treatment may be deferred because microscopic colitis does not increase mortality or colorectal‑cancer risk. 4

Begin conservative therapy with dietary fiber supplementation, adequate hydration, and avoidance of straining to control bleeding from hemorrhoids. 3

Patients with minor, self‑terminating bleeding (Oakland score ≤ 8) can be safely managed as outpatients, with colonoscopy scheduled within 2 weeks. 3
Hospital admission is not required unless there is major ongoing bleeding, hemodynamic instability, or other indications for inpatient care. 3
The 2‑week colonoscopy window aligns with guideline recommendations for evaluating unexplained rectal bleeding to rule out malignancy. 3