Sandbox: malabsorption

Diarrhea

Abbreviations: GI: Gastrointestinal; WBC: White blood cells; Plt: Platelets, Hgb: Hemoglobin, IgE: Immunoglobulin E, IgA: Immunoglobulin A

		Cause	Clinical manifestation									Lab findings									Extra intestinal findings	Cause/Pathogenesis	Gold standard diagnosis
			Symptoms								GI signs
			Duration		Diarrhea			Fever	Abdominal pain	Weight loss
												Stool exam					CBC			Other lab findings
Categories			Acute	Chronic	Watery	Bloody	Fatty					WBC	RBC	Ova/Parasite	Osmotic gap	Other	WBC	Hgb	Plt
		Crohns disease	-	+	+	+	+	+	+	+	Abdominal tenderness Tachycardia Hypotension				-		↑	↓	↑	Iron deficiency Vitamin B12 deficiency Elevated ESR Elevated CRP	Blood seen on rectal exam	Abnormal immune response to self antigens	Colonoscopy with biopsy
		Ulcerative colitis	-	+	+	+	+	+	+	+	Abdominal tenderness Tachycardia Hypotension Aphthous ulcers				-		↑	↓	↑	Hypoalbuminemia Hypokalemia Hypomagnesemia Iron deficiency Elevated ESR Elevated CRP	Skin rash Iritis Uveitis Seronegative arthritis Clubbing of the fingers Erythema nodosum	Abnormal immune response to self antigens	Colonoscopy with biopsy
		Celiac disease	-	+	±	-	±	-	+	+	Abdominal distention Mouth ulcers Hepatosplenomegaly Ascites				↑		-	↓	-	IgA endomysial antibody Anti-tissue transglutaminase antibody Anti-gliadin antibody	Signs of the fat-soluble vitamins A, D, E, and K deficiency Dementia Dermatitis herpetiformis	HLA-DQ2 HLA-DQ8 Innate responses to wheat proteins	IgA endomysial antibody IgA tissue transglutaminase antibody
		Cystic fibrosis	-	+	-	-	+	±	+	+					↑		-	↓	-	Positive DNA analysis for CFTR Evaluated nasal transepithelial potential difference (NPD)	Diabetes Recurrent upper and lower respiratory tract infections Infertility	Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) protein	Elevated sweat chloride ≥60 mmol/L
		Chronic pancreatitis	-	+	+	-	+	-	+	+	Abdominal tenderness				↑		-	-	-	Slightly elevated amylase and lipase Abnormal pancreatic function test	Malabsorption Diabetes mellitus	Repeated acute pancreatitis Alcohol abuse Genetic Autoimmune	Secretin stimulation test ERCP
		Infective colitis
		Ischemic colitis
		Mesenteric ischemia
		Lactose intolerance	+	+	+	-	-	-	+	-	Abdominal tenderness Hypotension Tachycardia Nausea and vomiting				↑		-	-	-	Hydrogen breath test	Bloating Flatulence Symptoms begin mainly after ingestion of lactose	Reduction of lactase enzyme activity or inability to produce persistent lactase Congenital lactase deficiency	Lactase activity assay
		Whipple's disease	-	+	+	-	+	±	+	+	Hepatosplenomegaly Ascites	-	-	-	↑	Fecal fat	↓	↓	↓/↑	Hypoalbuminemia	Abnormal extraocular movement Lymphadenopathy Hyperpigmentation Uveitis Endocarditis Encephalitis Dementia Pleural effusion	Tropheryma whipplei HLA-B27	Small intestine biopsy for Tropheryma whipplei testing PCR testing
		Tropical sprue	+	+	+	-	+	+	+	+	Pallor Angular stomatitis Mouth ulcers Edema				↑		-	↓	-	Low vitamin B12 Low folic acid Hypokalemia		Unknown Bacteria including Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae	Diagnosis of exclusion
		VIPoma	+	+	+	-	+	-	+	+	Tachycardia Abdominal distention Abdominal RUQ tenderness Nausea Vomiting				↓		-	-	-	Elevated VIP level Hypokalemia Hypochlorhydria or achlorhydria Low osmotic gap (<50 mOsm/kg)	Rash Facial flushing Dehydration Lethargy Muscle weakness	Primary secretory tumor	Elevated VIP levels Followed by imaging
		Zollinger-Ellison syndrome	-	+	+	-	+	-	+	+	Abdominal tenderness				↓		-	↓	-	Positive secretin stimulation test Elevated serum chromogranin A	Heartburn	Gastrin producing tumor mainly in duodenum	Elevated basal or stimulated serum gastrin> 120 pg/mL
		Eosinophilic gastroenteritis	-	+	+	-	+	-	+	+	Abdominal distention						↑	-	-	Elevated serum IgE levels Eosinophilia Elevated ESR Hypoalbuminemia	Other allergic disorders Associated with an identifiable dietary antigen	Autoimmune allergic response to food antigens	Eosinophilic infiltration of the gastrointestinal tract on biopsy
		Primary bile acid malabsorption	-	+	+	-	+	-	+	+					↑		-	↓	-	Low vitamins A, D, E, and K		Genetic defects in SLC10A2 (solute carrier family 10 member 2 gene)	Elevated total and specific bile acids in stool Positive SeHCAT
		Abetalipoproteinemia	-	+	+	-	+	-	+	+	Abdominal distension Visual field defect Dysarthria						-	-	-	Low triglyceride Low total cholesterol levels  Acanthocytes Low vitamin E levels	Visual impairment Ataxia	Autosomal recessive disorder caused by mutations encoding the microsomal triglyceride transfer protein (MTP)	Clinical findings and low triglyceride and cholesterol level
		Microscopic colitis	-	+	+	+	-	-	+	+	Abdominal tenderness				-		-	↓	-	Elevated autoantibodies include: RF ANA AMA ANCA	Fecal urgency Fecal incontinence Arthralgia Arthritis Uveitis	Mucosal immune responses to luminal factors in a genetically predisposed individual	Colonoscopy with mucosal biopsy with mononuclear infiltrates: Collagenous colitis is characterized by a colonic subepithelial collagen band >10 micrometers in diameter Lymphocytic colitis is characterized by ≥20 intraepithelial lymphocytes (IEL) per 100 surface epithelial cells
		Hyperthyroidism	-	+	+	-	-	±	+	+	Lump in the neck Proptosis Tremor Increased DTR						-	-	-	Elevated T4 Elevated T3 Decreased TSH	Lid lag Sweating Hyperpigmentation	Graves' disease Hashimoto's thyroiditis Toxic adenoma	TSH
		Irritable bowel syndrome	-	+	±	-	±	-	±	-	Abdominal tenderness Flatulence Hard stool in the rectal vault				-		-	-	-				Diagnosis of exclusion
		Cirrhosis	-	+	+	-	+	+	+	+	Jaundice Hepatosplenomegaly Abdominal distention Shifting dullness Asterixis Skin telangiectasias				↑		↓	↓	↓	Abnormal liver function tests Prolonged PT/PTT	Coagulopathy Portal hypertension Hepatic encephalopathy	Alcoholic liver disease Viral hepatitis Non-alcoholic steatohepatitis	Liver biopsy
		Short bowel syndrome	+	+	+	-	+	-	-	+	Abdominal distention Abdominal tenderness Peripheral edema Muscle atrophy				↑		-	↓	↑	Hypoalbuminemia High level of acute phase reactant Abnormal liver function tests Low vitamin A, B12, C,D, E, and K level High fecal fat	Prior intestinal surgery Crohn's disease Malignancy Radiation enteritis	Surgical intestinal resection
		Small bowel bacterial overgrowth	-	+	+	-	+	-	+	+	Muscle atrophy Abdominal distention						-	↓	-	Hypoalbuminemia Abnormal hydrogen breath test Lactic acidosis Abnormal fecal fat test	Malabsorption Vitamins deficiencies Rosacea	Excess bacteria in the small intestine Alterations in intestinal anatomy or GI motility,  Lack of gastric acid secretion	Diagnosis of exclusion
		X-linked agammaglobulinemia	-	+	+	-	+	+	+	+	Signs of dehydration Signs of infections				-		↓	↓	-	Hypogammaglobulinemia	Recurrent respiratory tract infections Gastroenteritis Bacterial infections Malabsorption	Inherited Gene defect	Low circulating immunoglobulin levels (IgG, IgA, IgM, IgE) on blood tests
		Intestinal lymphangiectasia	-	+	-	-	+	-	-	+	Peripheral edema Macular edema				-		↓	-	-	Hypoproteinemia Hypogammaglobulinemia	Protein-losing enteropathy Malabsorption Anergy Homograft rejection Pachydermoperiostosis	Dilatation of intestinal lymphatics	Intestinal biopsy
		Amyloidosis					+
		Mastocytosis
		Drug induced enteritis
		Giardiasis					+
		Strongyloidiasis
		Tuberculosis
		Chronic laxative abuse
		Pseudomembranous colitis	+	-	+	+/-	-	+	+	+/-	Abdominal tenderness Presence of pseudomembranes of endoscopy					Enzyme immunoassay (EIA) for C difficile toxin A and B Polymerase chain reaction (PCR) assay or C difficile antigen (glutamate dehydrogenase [GDH]) EIA	↑	↓	↓	Leukocytosis Elevated serum creatinine Hypoalbuminemia Anasarca Elevated serum lactate		Recent antibiotics use Recent surgery Colon cancer Diverticulitis Appendicitis	Stool exam CT
			Clinical manifestation									Lab findings									Extra intestinal findings	Cause/Pathogenesis	Gold standard diagnosis
			Symptoms								GI signs
			Duration		Diarrhea			Fever	Abdominal pain	Weight loss
												Stool exam					CBC			Other lab findings
			Acute	Chronic	Watery	Bloody	Fatty					WBC	RBC	Ova/Parasite	Osmotic gap	Other	WBC	Hgb	Plt
		CMV collitis		+		+		+/-	+	-		+/-	+	-	-		↓	-	-	CD 4 level decreased as it is maily associated with HIV
		Macrobacterium Aviom Complex		+		+		+/-	+	-		+/-	+	-	-		↓	-	-	Immune system analysis may show defects
		Colon cancer		+		+			+	+		-	+	-	-		-	↑/↓	-	May be associated with FAP gene or HNPCC gene
		Intestinal metastasis		+		+			+	+		-	+	-	-		↑/↓	↑/↓	↑/↓
		Infectious Diarrhea		+		+		-	+	+/-		+	+	-	-	Stool culture may be positive for responsible organism	↑	-	-			Trichuris trichiura infection EHEC Entamoeba Intestinal amebiasi
		Infectious Diarrhea	+			+		+	+	-		+	+	-	-	Stool culture may be positive for responsible organism	↑	-	-			Campylobacter Escherischia coli enterohemmorrhagic Clostridium Perfringens Salmonellosis
		Isosporiasis		+		+			+	-		+	+	-	-		↑	-
		Parasitic Diarrhea	+	+		+		-	+	+/-		+	+	+	-		↑	-	-			Amebiasis Intestinal Schistosomiasis Balantidiasis Trichuriasis