Diagnosis Flashcards
(103 cards)
Diarrhea.Types.Diagnostic-Classification
- Acute
- Chronic
- Inflammatory
- Fatty
- Watery
- Osmotic
- Secretory
- Abnormal-motility
- Exudative
- Ano-rectal-dysfunction
How can we clinically figure out the mechanism of diarrhea?
- Effect of fasting:
- Stops: Osmotic diarrhea
- Continues: secretory.
- Volume of stool:
- Small volume: osmotic, ano-rectal
- Large volume: secretory diarrhea.
- Osmolar gap:
- Large: Osmotic diarrhea
- Small: secretory diarrhea
- Blood and pus in feces: Exudative
- Fecal incontinence: Ano-rectal dysfunction
Diarrhea+Constipation+Abdominal-pain
Recurrent abdominal pain or discomfort and a marked change in bowel habit for at least six months, with symptoms experienced on at least three days of at least three months. Two or more of the following must apply:
- Pain is relieved by a bowel movement
- Onset of pain is related to a change in frequency of stool
- Onset of pain is related to a change in the appearance of stool.
IBS
ROME III critera
Diarrhea.Stool-Osmolar-gap
Osmolar gap = 290 − ([Na+] + [K+]) × 2
- Osmolar gap > 40 suggests osmotic diarrhea
- Osmolar gap < 40 suggests secretory diarrhea
Diarrhea.bloody + abdominal pain + age > 50
If abdominal pain and bloody diarrhea occur together in a patient older than 50 years, consider:
Ischemic Colitis
Diarrhea.chronic
Lasts longer than 4 weeks
Diarrhea.chronic.functional-vs-organic
- Fever
- Weight loss
- Arthritis
- Signs and symptoms of malabsorption
Diarrhea.Chronic.massive
Massive diarrhea WDHA syndrome (watery diarrhea, hypokalemia, achlorhydria
Vasoactive intestinal peptide tumors (VIPomas)
Diarrhea.Endocrine-causes
- Diabetes
- Hyperthyroidism
- Adrenal insufficiency
- Vasoactive intestinal peptide tumors (VIPomas)
- Carcinoid syndrome
- Medullary thyroid cancer
- Gastrinoma
- Mastocytosis
Diarrhea.inflammatory-causes
- Ulcerative colitis
- Crohn disease
- Microscopic colitis
- Eosinophilic gastroenteritis
Osmotic diarrhea: mechanism and examples
osmotically active solutes not absorbed from the gut lume causing passive water loss across the mucosa of the duodenum and jejunum, overwhelming the absorptive capacities of the ileum and colon
Diarrhea stops when oral intake stops
Volume < 1 L/day
Diarrhea.right-sided-valvular-heart-disease
Flushing
Abdominal pain
Wheezing
Right-sided valvular disease
Carcinoid
Diarrhea.Steatorrhea.causes
-
Maldigestion:
- Pancreatic exocrine insufficiency
- Bacterial overgrowth
- Liver disease
-
Malabsorption:
- Celiac sprue
- Tropical sprue
- Whipple disease
- Ischemia
Diarrhea.Steatorrhea.malabsorptive-causes
- Celiac sprue
- Tropical sprue
- Whipple disease
- Ischemia
Diarrhea.WorkUp
- StandardTests
- Fecal leukocytes
- Bacterial culture
- Ova and parasites
- Clostridium difficile toxin assay
- 72-hour quantitative stool collection for volume
- Stool electrolytes for osmolar gap calculation
- Qualitative and quantitative fecal fat on a high-fat diet (e.g., 72 hr, 100 g fat/day)
- Stool phenolphthalein (lax abuse)
- Tests for malabsorption
- d-Xylose testHydrogen breath test
- Tests for lactose intolerance
Diarrhea.WorkUp.d-Xylose
- Measures the absorptive capacity of the proximal small bowel
- Urine and blood are collected after 25 g oral xylose is administered
- Abnormal test suggests small bowel mucosal disease or bacterial overgrowth
- Normal in pancreatic enzyme deficiency
Diarrhea
Pruritus
Flushing
Abdominal pain
Headache
Urticaria pigmentosa—macular lesions that urticate when stroked (Darier’
Mastocytosis
- 24-hr urine histamine and metabolites
- Serum tryptase
- Skin biopsy
GI.bacterial-overgrowth-syndrome.Dx
- 14C-glycocholate breath test and 14C-d-xylose breath tests
- d-Xylose sensitivity and specificity approach 90%
- Hydrogen: Low sensitivity and specificity
- Normalization of Schilling test after antibiotics is highly suggestive
- Gold standard: small bowel aspirate culture
Multisystem-Sx.diarrhea-fever-arthritis-dementia-CHF
Presents with diarrhea, steatorrhea, abdominal pain, weight loss, migratory arthritis, and fever
Neurologic (dementia, ocular disturbances, meningoencephalitis, cerebellar symptoms), cardiac (congestive heart failure, pericarditis, valvular heart disease), and ophthalmologic features may be present
Whipple
Multisystem.GI-predominant
bloating+steatorrhea+dematitis+arthritis+hypocalcemia
Folate may be elevated
Bacterial overgrowth syndrome
A 56-year-old man has had profuse watery diarrhea for 3 months. Measured stool electrolytes are as follows: Na+ 30 mmol/L, K+ 85 mmol/L, Cl− 15 mmol/L, and HCO3− 18 mmol/L. Which diagnosis is least likely?
- Vasoactive intestinal peptide tumor (VIPoma)
- Lactose intolerance
- Laxative abuse
- Celiac sprue
VIPoma
The patient has a stool osmolar gap of 60. Since it is greater than 40, it is suggestive of an osmotic diarrhea. VIPomas cause secretory diarrhea and no osmotic gap. The other three all cause osmotic diarrhea.
Joint-Stiffness.Shoulder
Subacute shoulder pain, globally reduced motion; normal X-ray
Adhesive capsulitis
Joint-stiffness-and-pain.Shoulder
Limited adduction, weakness with active abduction, particularly when the arm is in neutral position
Supraspinatus tear
Pain.back
Pain of lumbar spinal stenosis is relieved by
Leaning forward