Blood and Mucus in Stools - Multiple Loose Episodes Per Day

Understanding the Blood Color

• Bright red blood = lower colorectum, rectum, or anus (distal source; rapid transit)
• Dark red/maroon blood = more proximal colon or right colon (slower transit, partial degradation of hemoglobin)
• Both colors in same patient = either disease spanning multiple colonic segments, or variable transit speed during an active flare

Key Differential Diagnosis

1. Inflammatory Bowel Disease (IBD)

"The major symptoms of UC are diarrhea, rectal bleeding, tenesmus, passage of mucus, and crampy abdominal pain."

• Harrison's Principles of Internal Medicine 22E, p. 2599

• Patients with proctitis pass fresh blood or blood-stained mucus, either mixed with stool or streaked on the surface of a normal stool, along with tenesmus (urgent, incomplete defecation).
• When disease extends beyond the rectum, blood is usually mixed with stool or there is grossly bloody diarrhea.
• With severe disease, the patient passes liquid stool containing blood, pus, and fecal matter. Diarrhea is often nocturnal and/or postprandial.

Colonoscopy with acute ulcerative colitis: severe colon inflammation with erythema, friability, and exudates. From Harrison's 22E.

2. Infectious Colitis (must be ruled out first)

"Infections with organisms such as Salmonella, Shigella, Amoeba, Giardia, E. coli O157:H7, and Campylobacter can be accompanied by bloody diarrhea, abdominal cramps, and an endoscopic mucosal appearance identical to that of ulcerative colitis."

• Goldman-Cecil Medicine, p. 1493

3. Ischemic Colitis

• Typically in elderly patients with cardiovascular risk factors (or young patients on vasoconstrictive drugs)
• Blood in stool, but usually less profuse
• Classically affects the "watershed" areas (splenic flexure, sigmoid), and the rectum is typically spared (distinguishing it from UC, which always involves the rectum)
• Yamada's Textbook of Gastroenterology, 7th Edition

4. Colorectal Cancer / Polyps

• Passage of blood clots is unusual in UC; if present, suggests other diagnoses such as tumor
• Chronic dark blood mixed with stool, weight loss, and change in bowel habits - particularly in older adults
• Sleisenger and Fordtran's Gastrointestinal and Liver Disease

5. Other Causes

• Radiation colitis - history of pelvic/abdominal radiotherapy
• Microscopic colitis (collagenous/lymphocytic) - watery diarrhea, usually no visible blood, normal endoscopy
• Diverticular bleeding - usually brisk bright red bleeding without significant mucus or inflammation

Immediate Workup

• Duration of symptoms (acute vs. chronic)
• Travel history, antibiotic use, sexual history
• Prior episodes, family history of IBD or colorectal cancer
• Fever, weight loss, night sweats

• Stool culture (bacterial pathogens: Shigella, Salmonella, Campylobacter, E. coli O157:H7)
• Stool PCR/GI panel (nucleic acid amplification test)
• C. difficile toxin PCR
• Ova and parasites (for Entamoeba histolytica, Giardia)
• Fecal white blood cells or fecal lactoferrin/calprotectin (marker of mucosal inflammation)

• CBC (anaemia, leukocytosis)
• CRP and ESR (inflammatory markers)
• Serum albumin (low in severe IBD)
• U&E/renal function (electrolyte derangement from diarrhea)

• Abdominal X-ray (exclude toxic megacolon: transverse colon diameter >6 cm)
• CT abdomen/pelvis if severe or uncertain

• Colonoscopy is the definitive investigation for IBD and to exclude malignancy
• Should be done after infectious causes are ruled out unless urgently needed
• Biopsies are essential for histopathological diagnosis
• Goldman-Cecil Medicine, p. 1499-1500

Management Overview

If Infectious - treat the cause:

• Shigella, Campylobacter: fluoroquinolone (ciprofloxacin) or azithromycin
• Amoebic dysentery: metronidazole followed by luminal agent (diloxanide furoate)
• C. difficile: oral vancomycin or fidaxomicin

If UC - based on severity:

• Mild-Moderate disease:
  • 5-ASA (mesalamine) oral ± topical (enemas for distal disease)
  • Sulfasalazine 3-6 g/day or mesalamine 2.4-4.8 g/day
  • Topical mesalamine enemas more effective for distal colitis
• Moderate-Severe disease:
  • Oral prednisone 40-60 mg/day
  • IV hydrocortisone 300 mg/day or methylprednisolone 40-60 mg/day for hospitalised patients
  • Budesonide MMX (Uceris) 9 mg/day is an option with fewer systemic effects
• Steroid-refractory/dependent disease:
  • Biologics: anti-TNF agents (infliximab, adalimumab), integrin inhibitors (vedolizumab), IL-12/23 inhibitors (ustekinumab)
  • Thiopurines (azathioprine, 6-MP) for maintenance
• Surgical (colectomy) for refractory disease, toxic megacolon, perforation, or dysplasia/cancer

Red Flag Features Requiring Urgent/Emergency Assessment

• ≥6 bloody stools per day
• Fever >37.5°C
• Tachycardia (pulse >90/min)
• Haemoglobin <10.5 g/dL
• Marked abdominal tenderness or distension (risk of toxic megacolon)
• Signs of peritonitis
• Passage of blood clots (raises concern for tumour or severe haemorrhage)

Disclaimer: This information is for educational purposes. Any patient with these symptoms should be evaluated promptly by a clinician for proper diagnosis and individualised management.

Chronic Course (2 Months) - Revised Clinical Assessment

What 2 Months of Symptoms Tells You

"An important distinction between acute bacterial infections and ulcerative colitis is that the diarrhea in infectious diseases tends to be limited to a period of days to a few weeks, whereas the diarrhea of ulcerative colitis is typically of longer duration."

• Yamada's Textbook of Gastroenterology, 7th Edition

• Most bacterial causes (Shigella, Campylobacter, Salmonella) resolve within 1-3 weeks
• 2 months of persistent symptoms essentially rules out common acute bacterial infections
• Protozoal infections (especially amoeba) and IBD are now the front-runners

Revised Priority Differential

1. Ulcerative Colitis (UC) - Most Likely

• Chronic diarrhea with blood and mucus
• Multiple episodes per day
• Duration >4 weeks with no infectious cause

2. Chronic Intestinal Amoebiasis (Entamoeba histolytica)

• Can cause prolonged illness lasting weeks-to-months
• Bloody diarrhea with mucus, colicky abdominal pain
• Ulcers characteristically in the cecum and ascending colon (covered with yellow exudate), but can be anywhere
• Endoscopy may look similar to IBD
• Critical point: If missed and patient is given steroids for presumed UC, amoebiasis can rapidly disseminate and become life-threatening
• Must be excluded before starting immunosuppression

3. Intestinal Tuberculosis

• Particularly relevant in TB-endemic regions (South Asia, Sub-Saharan Africa)
• Can present with chronic diarrhea, blood in stool, weight loss, night sweats, low-grade fever
• Primarily involves ileocecal region; can closely mimic Crohn's disease
• Must be excluded before starting biologics/immunosuppressants

4. Crohn's Disease (Colonic)

• Less commonly presents with gross rectal bleeding than UC
• Consider if there are: perianal disease (fistulas, skin tags), upper GI symptoms, skip lesions, or weight loss out of proportion

5. Colorectal Cancer

• 2 months of rectal bleeding in adults (especially >40 years) warrants exclusion
• Particularly if there is significant weight loss, family history, or change in stool calibre

Priority Investigation Plan

Step 1 - Bloods (same day)

• CBC - check haemoglobin (anaemia from chronic blood loss), WBC, platelets
• CRP and ESR - elevated in active IBD and infection
• Serum albumin - low in severe/prolonged IBD; nutritional marker
• LFTs, U&E, renal function
• Blood cultures if febrile

Step 2 - Stool Studies (send immediately)

• Stool microscopy for trophozoites of Entamoeba histolytica (3 fresh samples on different days for maximum sensitivity)
• Stool culture - bacterial pathogens
• Stool PCR/GI multiplex panel - covers bacteria, parasites, viruses in one test
• C. difficile toxin PCR
• Fecal calprotectin - highly sensitive marker of mucosal inflammation; elevated in IBD and infectious colitis, helps distinguish from IBS
• Ova and parasites - Giardia antigen

Step 3 - Imaging

• Plain abdominal X-ray - look for toxic megacolon (transverse colon >6 cm), free gas under diaphragm, or faecal loading
• CT abdomen/pelvis with contrast - if severe, to assess extent of colitis, complications, and exclude perforation or abscess

Step 4 - Endoscopy (once infection excluded or as urgent)

• Colonoscopy with biopsy is the definitive investigation
• Biopsies distinguish UC from Crohn's from amoebic colitis from TB from CMV colitis histologically
• Goldman-Cecil Medicine: "Colonoscopy is the initial endoscopic test for patients who present with lower GI symptoms such as diarrhea and hematochezia"

Step 5 - TB Workup (if in endemic region or high suspicion)

• Chest X-ray
• Mantoux/TST or IGRA (QuantiFERON-TB Gold)
• Tissue biopsy PCR for TB from colonoscopy specimens

Management - Once Infectious Causes Excluded

If Amoeba Confirmed:

• Metronidazole 400-800 mg three times daily for 5-10 days (tissue amoebicide)
• Followed by luminal agent: diloxanide furoate 500 mg three times daily for 10 days (to clear intestinal cysts)

If UC Confirmed - Treatment Based on Severity:

• 5-ASA (mesalamine) is first-line
  • Oral mesalamine 2.4-4.8 g/day
  • If distal colitis: add mesalamine enemas (rectal) - combination oral + topical is more effective than either alone
  • Sulfasalazine 3-6 g/day is an alternative (cheaper, but more side effects)

• Oral prednisolone 40-60 mg/day - most require this to induce remission
• Once remission achieved, taper slowly and transition to maintenance with 5-ASA or azathioprine
• Harrison's 22E: "The majority of patients with moderate to severe UC benefit from oral or parenteral glucocorticoids"

• IV methylprednisolone 40-60 mg/day or IV hydrocortisone 300 mg/day
• IV fluids, correct anaemia (blood transfusion if Hb <8 g/dL)
• DVT prophylaxis (IBD patients have elevated thrombotic risk)
• Nutritional support
• If no response in 3-5 days: rescue therapy with infliximab (anti-TNF) or ciclosporin
• If medical therapy fails: urgent colectomy

Maintenance (after remission):

• Mesalamine long-term for UC
• If steroid-dependent: azathioprine or 6-mercaptopurine
• If moderate-severe with biologic need: infliximab, adalimumab, vedolizumab, or ustekinumab
• Goodman & Gilman's: Mesalamine for induction and maintenance of remission in mild-to-moderate UC; combination with glucocorticoids for severe UC

Warning Signs Requiring Same-Day Hospital Admission

• Fever above 38°C
• Pulse >90 beats/minute
• Abdominal distension or severe tenderness
• Passing >6 bloody stools in one day
• Haemoglobin dropping (pallor, breathlessness, dizziness)
• Significant weight loss (>5-10% body weight)
• Signs of dehydration (dry mouth, reduced urine output)

Practical Next Step

1. See a gastroenterologist urgently - do not start corticosteroids empirically without excluding amoeba and TB first
2. Send stool samples (culture, microscopy for amoeba, C. diff PCR, calprotectin)
3. Blood tests today - CBC, CRP, albumin, ESR
4. Colonoscopy with biopsy to be arranged as soon as possible (or urgently if severe)

Disclaimer: This is clinical educational information only. A patient with 2 months of bloody diarrhea needs prompt evaluation by a physician - please seek medical care urgently.

Updated Assessment - Significant Escalation in Severity

Clinical Interpretation of New Symptoms

Dizziness on Standing = Orthostatic Hypotension

• Two months of daily bloody stools = slow but continuous haemorrhage
• The body compensates for gradual blood loss, masking obvious signs of dehydration (mucous membranes may still look normal)
• But when the patient stands, the cardiovascular system cannot maintain perfusion against gravity - hence dizziness
• This is a red flag for haemoglobin likely <8-9 g/dL (moderate-severe anaemia)

"Tachycardia and hypotension may be present secondary to dehydration or anaemia from chronic blood loss."

• Tintinalli's Emergency Medicine

Fever and Chills = Systemic Inflammation / Possible Infection

1. Severe active IBD itself (systemic inflammatory response) - fever is one of the Montreal S3 severity criteria for UC
2. Superimposed infection on top of IBD (e.g. C. difficile flare, CMV colitis)
3. Complication - colonic perforation, abscess formation, or bacteraemia from translocation through a damaged colonic wall

Severe Left-Sided Colicky Pain

• Left-sided abdominal pain in bloody diarrhea = sigmoid colon and descending colon involvement
• This is the classic distribution of ulcerative colitis (starts at rectum, extends proximally - left-sided disease is the most common pattern)
• "Colicky" pain that precedes and is partially relieved by defecation is typical of colonic inflammation
• Severe colicky pain with fever raises concern for:
  • Severe/fulminant colitis
  • Early toxic megacolon (transverse colon dilation >6 cm with fever, abdominal pain, systemic inflammation)
  • Colonic perforation (sudden severe pain, peritoneal signs)

"Toxic megacolon is a complication of severe ulcerative colitis in which large bowel dilation is present on abdominal radiograph or CT in the setting of fever, abdominal pain, and laboratory markers of systemic inflammation. Treatment requires hospital admission."

• Tintinalli's Emergency Medicine

Revised Severity Assessment

Immediate Actions Required

This patient needs hospital admission today. Do not delay.

What Will Happen in Hospital

On Arrival - Emergency Assessment:

1. Vital signs - lying and standing blood pressure (confirm orthostatic drop), pulse rate, temperature, oxygen saturation
2. IV access established immediately
3. Urgent bloods:
   • Full blood count - haemoglobin level (expect low), WBC, platelets
   • CRP and ESR
   • Serum electrolytes (Na, K, Cl, bicarbonate)
   • Renal function (urea, creatinine)
   • Serum albumin
   • Blood cultures (×2 sets, given fever and chills)
   • Coagulation screen
   • Group and screen (for possible transfusion)
4. Stool samples:
   • C. difficile toxin PCR (urgent - superimposed C. diff on IBD is common and worsens outcome)
   • Stool culture
   • Microscopy for Entamoeba histolytica
5. Abdominal X-ray - rule out toxic megacolon (transverse colon >6 cm), free air under diaphragm (perforation)
6. CT abdomen/pelvis with contrast - assess extent of colitis, bowel wall thickening, free fluid, abscess

Inpatient Treatment:

• Blood transfusion

• IV methylprednisolone 40-60 mg/day OR IV hydrocortisone 100 mg four times daily
• IV fluids and electrolyte correction
• Nutritional support (high-protein diet or nasogastric feeding if not tolerating food)
• DVT prophylaxis (IBD carries increased clotting risk)
• Nil by mouth if toxic megacolon is suspected

• Infliximab (anti-TNF biologic) - 5 mg/kg IV
• OR Cyclosporin 2-4 mg/kg IV - effective in 82% of steroid-refractory UC cases
• Harrison's Principles of Internal Medicine 22E

• Emergency surgical consultation
• Urgent colectomy

Critical Rule Before Starting Steroids:

• Exclude C. difficile (stool PCR result needed)
• Exclude amoeba (stool microscopy)
• Exclude CMV colitis if immunocompromised or steroid-refractory (tissue biopsy)
• Giving steroids to someone with active amoebiasis can be fatal

The Overall Picture

Bottom Line

• Symptomatic anaemia (dizziness on standing)
• Systemic infection/inflammation (fever + chills)
• Active colonic disease (severe left-sided colicky pain)

Disclaimer: This is clinical educational information. The symptoms described require immediate in-person medical evaluation and should not be managed based on this information alone.

Diet for IBS (Irritable Bowel Syndrome)

Important note first: Before reading this, the symptoms we discussed earlier - 2 months of bloody mucoid diarrhea, fever, chills, left-sided pain, and dizziness on standing - are NOT consistent with IBS. IBS does not cause blood in stool, fever, or anaemia. Those symptoms require urgent medical investigation. This diet guide applies to confirmed IBS only.

Why Diet Matters in IBS

"Meal-related symptoms are reported by about two thirds of patients and include abdominal pain, bloating, and flatulence, often triggered by larger meals, foods rich in carbohydrates or fats, coffee, alcohol, and spicy foods."

• Goldman-Cecil Medicine

Step 1 - Food and Symptom Diary

• Everything eaten and drunk
• Timing and nature of symptoms
• Stool frequency and consistency (use the Bristol Stool Scale)
• Stress levels

Step 2 - General Dietary Principles (All IBS Subtypes)

Step 3 - The Low-FODMAP Diet (Most Evidence-Based)

"A diet that is low in FODMAPs can improve global IBS symptoms, especially in patients with predominant diarrhea, and also can reduce abdominal pain, abdominal bloating, and abnormal bowel habits. This diet is best explained and supervised by a trained dietitian."

• Goldman-Cecil Medicine

The Low-FODMAP Protocol Has 3 Phases:

High-FODMAP Foods to AVOID (Phase 1):

Low-FODMAP Foods that are SAFE to eat:

Step 4 - Fibre Considerations

• Psyllium husk (Ispaghula) - 5-10 g/day, build up gradually
• Oats
• Bananas, carrots

"Guidelines specifically recommend soluble (e.g., psyllium) but not insoluble fiber (e.g., wheat bran). Fiber may cause abdominal discomfort and gas, so lower doses should be used initially."

• Goldman-Cecil Medicine

Step 5 - Subtype-Specific Adjustments

IBS-D (Diarrhea-Predominant):

• Strict low-FODMAP adherence most important
• Limit caffeine and alcohol strictly
• Avoid raw bran, high-fat meals
• Cooked, low-residue foods are better tolerated
• Probiotics (Lactobacillus, Bifidobacterium strains) may help

IBS-C (Constipation-Predominant):

• Increase soluble fibre gradually
• Ensure adequate fluid intake (dehydration worsens constipation)
• Prune juice (small amounts) or kiwi fruit can help
• Regular physical activity stimulates gut motility

IBS-M (Mixed):

• Start with general principles + low-FODMAP
• Identify specific triggers through food diary
• Adjust fibre based on predominant symptom at any given time

Other Dietary Considerations

What to Avoid Regardless of Subtype

• Chewing gum (contains polyols like sorbitol/xylitol)
• Carbonated drinks (gas and bloating)
• Skipping meals (disrupts gut motility rhythm)
• Eating very late at night
• Ultra-processed foods (additives, emulsifiers can worsen gut barrier function)

Practical Sample Day (Low-FODMAP, IBS-D)

Key Takeaways

1. Low-FODMAP diet is the most evidence-based dietary approach for IBS - works best under dietitian supervision
2. Keep a food diary first to identify personal triggers
3. Soluble fibre helps; insoluble bran worsens symptoms
4. Low-FODMAP is a temporary elimination then reintroduction process - not a lifelong restrictive diet
5. General habits (regular meals, smaller portions, slow eating, adequate water) matter alongside specific food choices
6. Blood in stool, fever, weight loss, or anaemia are never IBS - always investigate these

Diet for Ulcerative Colitis

The Central Principle

"A healthy Mediterranean diet will benefit patients with IBD. No diet has consistently been found to decrease the rate of flares in adults with IBD. A diet low in red and processed meat may reduce ulcerative colitis flares."

• AGA Clinical Practice Update on Diet in IBD, Gastroenterology 2024 (Hashash et al., PMID 38276922)

Phase 1 - During an Active Flare

General Principles During a Flare:

Foods to EAT During a Flare:

• White rice, white bread, plain crackers, rice cakes
• Plain pasta or noodles (white, not wholegrain)
• Boiled or mashed white potato (no skin)
• Oatmeal (plain, well-cooked)
• Cornflakes or rice-based cereals

• Chicken (boiled, baked, without skin)
• Fish (steamed or baked - salmon, white fish)
• Eggs (boiled, poached, scrambled - not fried)
• Tofu
• Well-cooked lentils (small amounts if tolerated)

• Well-boiled carrots, courgette (zucchini), butternut squash
• Peeled cucumber
• Mashed sweet potato (peeled)
• Avoid: broccoli, cauliflower, cabbage, onion, peppers (raw), corn

• Banana (ripe)
• Tinned peaches, pears (in juice, not syrup)
• Cooked apple (peeled, no skin)
• Avoid: high-fibre fruits (apples with skin, pears, berries, dried fruit)

• If lactose-tolerant: natural yogurt (small amounts), hard cheese
• If lactose causes symptoms: use lactose-free milk, lactose-free yogurt, or plant-based alternatives
• Note: lactose intolerance is common during flares even if normally tolerated - temporarily limit dairy

• Water (sip regularly throughout the day)
• Oral rehydration solutions (ORS) if significant diarrhea
• Diluted fruit juice (not apple or pear - high fructose)
• Weak tea (no milk if lactose avoiding)
• Avoid: fizzy drinks, alcohol, caffeine, full-strength fruit juices

Foods to AVOID During a Flare:

Phase 2 - During Remission (When Symptoms Are Controlled)

The Mediterranean Diet - First-Line Recommendation

Foods with Evidence of Reducing UC Flares:

• Omega-3 fatty acids (oily fish: salmon, mackerel, sardines, herring) - anti-inflammatory effect on colonic mucosa
• Fermented foods (natural yogurt, kefir, miso) - support gut microbiome
• Soluble fibre (oats, psyllium, cooked vegetables) - feeds beneficial gut bacteria, produces butyrate which nourishes colonocytes
• Curcumin (turmeric) - some evidence as adjunct to maintain remission in mild-moderate UC; anti-inflammatory

Foods Linked to Increasing UC Flares - LIMIT OR AVOID:

• Red meat and processed meats (bacon, sausages, hot dogs) - AGA advises a diet low in red and processed meat to reduce UC flares
• Ultra-processed foods - emulsifiers (carrageenan, polysorbate-80) disrupt mucosal barrier and alter microbiome
• Refined sugars and sweetened beverages
• High-fat Western diet foods
• Alcohol - directly irritates mucosa and can trigger flares
• NSAIDs (ibuprofen, naproxen) - not food, but a common trigger for UC flares; always tell your doctor before taking

Nutritional Deficiencies Common in UC - Monitor and Supplement

Practical Sample Day (UC in Remission - Mediterranean Style)

Practical Sample Day (UC During Active Flare)

Key Rules to Remember

1. Diet does not replace medication - mesalamine, steroids, and biologics treat the disease; diet supports recovery and overall health
2. Flare phase = low residue, soft, easy-to-digest foods - rest the colon
3. Remission phase = Mediterranean diet - variety of plant foods, oily fish, olive oil, limit processed and red meat
4. Always correct nutritional deficiencies - especially iron (from chronic bleeding), folate (if on sulfasalazine), and vitamin D/calcium (if on steroids)
5. Keep a food and symptom diary - UC triggers are personal; identify your own
6. Work with a registered dietitian - especially for ongoing management; the AGA specifically recommends this
7. Avoid alcohol, NSAIDs, and ultra-processed foods consistently - these are known flare triggers

Disclaimer: This dietary guide is for educational purposes. Nutritional management of UC should be individualised with the help of a gastroenterologist and registered dietitian.