INTRODUCTION:
- An increase in frequency of defecation urgency, or decrease in stool consistency (typically >3loose stools per day) for >4weeks.
- Abnormal stool form is the most important defining factor frequent defecation with normal consistency is termed pseudo diarrhoea.
- Etiologies include osmotic, secretory, malabsorptive, inflammatory, infectious, and hyper motility.
- Infectious causes of chronic diarrhea are uncommon in immunocompetent patients. Parasitic etiologies are more common than bacterial.
STAGES OF DIARRHOEA
- Mild-2-5 times in a day, Sudden onset
- Moderate-10-12 times a day, Gradually
· Severe-More than 12 times in a day ,Sudden &gradually
OSMOTIC DIARRHEOA
Absorption of water in the intestines is dependent on adequate absorption of solutes. If excessive amounts of solutes are retained in the intestinal lumen, water will not be absorbed and diarrhoea will result. Osmotic diarrhoea typically results from one of two situations:
- Ingestion of a poorly absorbed substrate: The offending molecule is usually a carbohydrate or divalent ion. Common examples include mannitol or sorbitol, Epson salt (MgSO4) and some antacids (MgOH2).
- Malabsorption: Inability to absorb certain carbohydrates is the most common deficit in this category of diarrhoea, but it can result virtually any type of malabsorption. A common example of malabsorption, afflicting many adults humans and pets is lactose intolerance resulting from a deficiency in the brush border enzyme lactase. In such cases, a moderate quantity of lactose is consumed (usually as milk), but the intestinal epithelium is deficient in lactase, and lactose cannot be effectively hydrolysed into glucose and galactose for absorption. The osmotically-active lactose is retained in the intestinal lumen, where it “holds” water. To add insult to injury, the unabsorbed lactose passes into the large intestine where it is fermented by colonic bacteria, resulting in production of excessive gas.
SECRETORY DIARRHEOA
Large volumes of water are normally secreted into the small intestinal lumen, but a large majority of this water is efficiently absorbed before reaching the large intestine. Diarrhoea occurs when secretion of water into the intestinal lumen exceeds absorption.
Many millions of people have died of the secretory diarrhoea associated with cholera. The responsible organism, Vibrio cholera, produces cholera toxin, which strongly activates adenylyl cyclase, causing a prolonged increase in intracellular concentration of cyclic AMP within crypt enterocytes. This change results in prolonged opening of the chloride channels that are instrumental in secretion of water from the crypts, allowing uncontrolled secretion of water. Additionally, cholera toxin affects the enteric nervous system, resulting in an independent stimulus of secretion.
Exposure to toxins from several other types of bacteria (e.g. E. coli heat-labile toxin) induce the same series of steps and massive secretory diarrhoea that is often lethal unless the person or animal is aggressively treated to maintain hydration.
TYPES OF DIARRHOEA
ACUTE DIARRHOEA: The most common, acute diarrhoea is loose watery diarrhoea that lasts one to two days. This type doesn’t need treatment and it usually goes away after a few days.
CAUSES:
- Viral infections. Many viruses cause diarrhoea, including norovirus. Viral gastroenteritis is a common cause of acute diarrhoea.
- Bacterial infections. Several types of bacteria can enter body through contaminated food or water and cause diarrhoea. Common bacteria that cause diarrhoea include Campylobacter, Escherichia coli.
- Parasitic infections. Parasites can enter your body through food or water and settle digestive tract. Parasites that cause diarrhoea include Cryptosporidium enteritis, Endamoeba histolytica, and Giardia lamblia, Cyclospora&Isosopra
TREATMENT:
Diet: Patient takes adequate oral fluids containing carbohydrates &electrolytes.
Patients find it more comfortable to rest the bowel by avoiding high fibre foods ,fats, milk products ,caffeine and alcohol.
Rehydration: Severe diarrhoea ,dehydration can occur quickly, especially in children and older adults.Oral rehydration with fluids containing glucose,Na+,K+,CL-
Antibiotic Therapy
Empiric Treatment-Ciprofloxacin 500mg OD for 3days
Ofloxacin 400mg OD
CHRONIC DIARRHOEA:
Diarrhoea that lasts for more than four weeks or comes and goes regularly over a long period of time is called chronic diarrhoea.
CAUSES:
Viruses– Norwalk virus, enteric adenoviruses, Arbovirus, cytomegalovirus and viral hepatitis. Rotavirus is a common cause of childhood diarrhoea.
Bacteria and parasites. E. coli or parasites through contaminated food or water, leads to diarrhoea. When traveling in developing countries, diarrhoea caused by bacteria and parasites is often called traveller’s diarrhoea.
- Medications. Antibiotics, can cause diarrhoea called Pseudomembranous colitis Antibiotics alleviate infections by killing bad bacteria, but they also kill good bacteria. This disturbs the natural balance of bacteria in intestines, leading to diarrhoea. Other drugs that cause diarrhoea are anti-cancer drugs and antacids with magnesium.
- Lactose intolerance. Lactose is a sugar found in milk. People who have difficulty digesting lactose have diarrhoea after eating dairy products.
- Fructose. Fructose is a sugar found naturally in fruits and honey. It’s sometimes added as a sweetener to certain beverages. Fructose can lead to diarrhoea in people who have trouble digesting it.
- Artificial sweeteners. Sorbitol, erythritol and mannitol artificial sweeteners are nonabsorbable sugars found in chewing gum and other sugar-free products can cause diarrhoea in some otherwise healthy people.
- Surgery. Partial intestine or gallbladder removal surgeries can sometimes cause diarrhoea.
Digestive disorders. Irritable bowel syndrome, Crohn’s disease, ulcerative colitis, celiac disease, microscopic colitis and small intestinal bacterial overgrowth (SIBO).
SIGNS&SYMPTOMS
SIGNS
- Sunken eye ball
- Dry tongue& mucosa
- Poor skin turgor
- Low blood pressure
- Lethargy
- Weight loss
SYMPTOMS
- Passage of loose stool
- Increased frequency of passage of stool
- Loose, watery consistency of stool
- Low urine output
- Increased volume of stool
- Vomiting
RISK FACTORS:
1.Osmotic
- Excess ingestion of non-absorbable carbohydrates, lactose intolerance & celiac disease
2.Secretory
- -Post surgical: extensive small bowel resection/ileal surgery, vagotomy, bile acid malabsorption.
- History of neuroendocrine disease
- History of stimulant laxative abuse
- Dysmotility syndromes.
3.Malabsorptive
- Chronic alcohol abuse
- Chronic pancreatitis
- Celiac disease
4.Inflammatory
- IBD, NSAID use
- Thoracoabdominal radiation, HIV/AIDS
- Antibiotic use
5.Hypermotility
- Psychosocial stress
- Preceding infection
COMPLICATIONS:
- Fluid and electrolyte abnormalities, Acute kidney injury
- Malnutrition, anaemia, unintentional weight loss
- Malignancy (colon cancer in IBD,small bowel cancer in celiac disease)
- Infection with immunomodular, biologic and corticosteroid therapies for IBD
PHYSICAL EXAMINATION
General: Volume depletion ,nutritional status ,recent weight loss
Skin: Flushing, erythema nodosum, pyodema gangrenosum, ecchymoses, dermatitis herpetiformis, hyperpigmentation.
Neck: Goiter, lymphadenopathy(whipple disease)
CVS: Tachycardia,heart murmur
Pulmonary: Wheezing
Abdomen: Hyperactive bowel sounds,abdominal distension,diffuse tenderness.
Anorectal: anorectal fistulas,fissures,fecal impaction
Extremitis: arthritis
Neurologic: tremor
DIAGNOSTIC TESTS:
- Initial tests (lab, imaging)
- Test patients with alarm symptoms or persistent symptoms and no identifiable cause.
- Blood :CBC,electrolytes,total protein,albumin,TSH,T4,erythrocyte sedimentation rate,C-reactive protein,IgA anti-tissue transglutamine,iron studies
- Stool: WBCs or fecal calprotein,culture,ova and parasites,Giardia stool antigen,, electrolytes,occult blood,osmolality,quanlitative fecal fat .
- CT or MRI to evaluate the structure of the GI tract
MANAGEMENT:
- Plenty of fluids to prevent dehydration
- Oral rehydration drinks to replace lost salts and minerals. An alternative is one part unsweetened pure fruit juice diluted with four parts of water.
- Nutrition rich foods-the vicious circle of malnutrition &diaarhoea can be broken by continuing to give nutrient rich foods
- ORT: They contain 2-3 g/dL of glucose, 45-90 mEq/L of sodium, 30 mEq/L of base, and 20-25 Me q/L of potassium. Osmolality is 200-310 mOsm/L.-1liter 1day.
- In children with severe acute malnutrition and diarrhea, low osmolarity oral rehydration solution (ORS) ( osmolarity: 245, sodium: 75 mEq/L) with added potassium (20 m mol/L)
- Diarrhoea 30 episodes give IV fluids-Ringer lactate TID
- Ofloxacin+ornidazole 200+500mg BD for 5days
- Racecodotril 100mg BD 3days
- Sporlac sachets-TID for 3-5days
- Entero germinal respules-BD for 3-5days
- If abdominal pain-adults-Buscopan&,Peadiatrics-Cyclopam syrup
DIET:
- Elimination diet: avoid gluten-containing foods,non absorbable carbohydrates,lactose containing products&food allergens depending on etiology of diarrhoea.
- Low FODMAP (Fermentable oligosaccharides, disaccharides,monosaccharides&polyols)diet helps symptoms in upto 75% of IBS patients.
- High carbohydrate intake and obesity have been linked to chronic diarrhoea.
PATIENT EDUCATION:
Wide variation in normal bowel habits
Diarrhoea is generally defined as 3 or more loose bowel movements per day for over 4 weeks.
- Drink plenty of liquids, including water, broths and juices. Avoid caffeine and alcohol.
- Add semisolid and low fiber foods gradually as your bowel movements return to normal. Try soda crackers, toast, eggs, rice or chicken.
- Avoid certain foods such as dairy products, fatty foods, high-fiber foods or highly seasoned foods for a few days.
RED FLAGS Hypotension,sunken eyes
PEARL: ORS therapy
REFERENCE:
5 minutes consultant.com