Definition: It is an increase in the fluid rate and frequency of stool as a result of the deterioration of the balance in the absorption and / or secretion function of the intestines.
Classification of diarrheas according to pathophysiology
Secretory diarrhea
• Laxative habit (non-osmotic)
• Drugs and toxins
• Inflammatory bowel disease
• Diverticulitis, vasculitis
• Chronic alcohol intake
• Bowel resection
• Neuroendocrine tumors
• Cancer (colon Ca, lymphoma, villous adenoma)
• Addison's disease
• Idiopathic secretory diarrhea
• Ileal bile acid malabsorption
from motility disorder
• irritable bowel syndrome
• Hyperthyroidism
• Prokinetic drugs
• Visceral neuromyopathies
• Postvagotomy
Oily diarrhea
• Malabsorption syndromes
• Lymphatic obstruction
Inflammatory diarrhea
• Infections
• Inflammatory bowel disease
• Malignancies (colon carcinoma, lymphoma)
• Intake of diverticulitis and ischemic colitis
• Eosinophilic gastroenteritis
• Radiation colitis
• Lymphocytic and collagenous colitis
Osmotic diarrhea
• Taking medication containing magnesium, phosphate, sulfate salts
• Carbohydrate malabsorption
• Osmotic laxatives (lactulose)
• Gluten enteropathy, Whipple's disease, chronic pancreatitis
• In osmotic diarrhea, there is an increase in osmotic load in the intestinal lumen, water and electrolytes pass passively into the lumen. However, in secretory diarrhea, there is an active passage of water and electrolytes from the intestines to the lumen.
• Differentiation of osmotic and secretory diarrhea:
While a decrease in osmotic diarrhea is expected with fasting, secretory diarrhea continues despite hunger.
The normal value of the fecal osmotic gap [290 - 2 x (fecal Na+fecal K)] is 50-100 mosm/kg. If the fecal osmotic gap is >100, osmotic diarrhea should be considered, and if it is <50, secretory diarrhea should be considered.
Classification of diarrhea according to the place of involvement
• Large amount of stool, low number of defecations, painless and bloodless diarrhea, and the patient's relief from the toilet are mostly seen in small bowel pathologies and can be defined as small bowel type diarrhea.
• Painful, bloody, frequent, less frequent and tenesmic diarrhea is more common in colonic pathologies and is defined as colonic diarrhea.
Classification of diarrhea by duration
• Diarrhea lasting less than 2 weeks: Acute
• Diarrhea lasting 2-4 weeks: Persistent
• Diarrhea lasting longer than 4 weeks: Chronic
Acute diarrhea
General Information
• The most common cause is infections and viruses are the most common cause of infectious acute diarrhea. The most common cause of acute viral gastroenteritis in adults is Norwalk virus/ Norovirus.
• Medications (especially antibiotics) are the most common cause of acute non-infectious diarrhea.
• Another condition to be considered in acute diarrhea is food poisoning.
• Acute infectious diarrhea can be clinically examined in four groups:
" Simple watery diarrhea: Rotavirus, Norwalk and other viruses, ETEC (enterotoxigenic E. coli) etc.
Bloody diarrhea (dysentery): Shigella, C. jejuni, EIEC (enteroinvasive E. Coli), EHEC ( enterohemorrhagic E. Coli), E. histolytica etc.
Persistent diarrhea (> 15 days): Giardia, EPEC (enteropathogenic E. Coli) etc.
Cholera-like diarrhea: V. cholerae, ETEC (enterotoxigenic E. coli) etc.
Clinic and Diagnosis
• Most acute diarrhea is mild-moderate and resolves spontaneously with elimination of the suspected cause or 1-2 days of supportive treatment, and does not require further investigation and treatment.
• The following conditions require further investigation for a more serious clinical pathology:
Diarrhea with profuse and dehydration
Gross bloody diarrhea
Fever > 38.5°C
Diarrhea that does not improve for 2 days
recent history of antibiotics
Presence of epidemic in society
Over 50 years of age and associated with severe abdominal pain
patient over 70 years old
Immunosuppressed patient
• If food intoxication and drug-excluded infectious diarrhea is suspected in a patient with acute diarrhea, stool microscopy should be performed first.
• Stool microscopy and pathologies that should be considered first:
Abundant PNL and abundant erythrocytes: Shigella, non-typhoidal Salmonella
Antibiotic history with abundant PNL and abundant erythrocytes: C. difficile
Abundant lymphocytes: Salmonella typhi (enteric fever)
Abundant erythrocytes only: E. histolytica, EHEC diarrhea
Typical trophozoids: E. histolytica, Giardia
Nothing seen: Viral diarrheas
• In giardia, viral and amoebic diarrhea, leukocytes are not expected in the stool.
• Lactoferrin in stool can be used instead of microscopic leukocyte determination and is more valuable in demonstrating inflammatory diarrhea.
• Stool culture is the most important diagnostic method in detecting the causative agent.
Treatment
• The first step should be the necessary fluid and electrolyte replacement.
• Vira! Treatment of diarrhea and food poisoning is symptomatic.
• Agents that reduce motility and secretions (loperamide) can be used in mild to moderate diarrhea without fever and bloody diarrhea.
• Antibiotics are given for the etiology in bacterial and protozoal diarrhea.
• Empirical antibiotics should be started without waiting for the causative agent in immunodeficiency, mechanical valve, vascular graft and elderly patients.
• Empirical antibiotics should be started without waiting for the causative agent in patients with moderate-to-severe diarrhea, fever, and diarrhea with stool leukocytes (or stool lactoferrin) or blood.
Chronic Diarrhea
• Unlike acute diarrhea, it is mostly due to non-infectious causes.
• Generally, the etiology includes irritable bowel disease, inflammatory bowel diseases, causes of malabsorption, other diseases that impair intestinal motility, etc. is responsible.
• Fluid, electrolyte and vitamin deficiencies, if any, should be eliminated first in the treatment. Specific treatment is planned for the underlying cause.