|
|
Line 7: |
Line 7: |
|
| |
|
| ==Differential diagnosis== | | ==Differential diagnosis== |
| The tree diagram below gives a clear understanding as to how to asses a patient presenting with [[diarrhea]] lasting more than 4 weeks.
| |
|
| |
|
| |
| {{familytree/start}}
| |
| {{familytree | | | A01 | | | A01= Adults with chronic diarrhea (> 4 weeks)}}
| |
| {{familytree | | | |!| | | | }}
| |
| {{familytree | | | B01 | | | B01=<div style="float: left; text-align: left; height: 36em; width: 30em; padding:1em;"> '''Characterize the symptoms:'''<br>
| |
| ❑ Onset (congenital, abrupt or gradual) <br> ❑ Pattern (continuous or intermittent) <br> ❑ Duration <br> ❑ Stool characteristics (watery, bloody or fatty) <br> ❑ [[Fever]] <br> ❑ [[Abdominal pain]] <br> ❑ [[Weight loss]] <br> ❑ Fecal incontinence
| |
| ----
| |
| '''Obtain a detailed history:'''<br>
| |
| ❑ Aggravating factors ([[diet]] or [[stress]]) <br> ❑ Over-the-counter drugs or use of prescription <br> ❑ Previous evaluations (objective records, radiograms or [[biopsy]] specimens) <br> ❑ Radiation therapy or surgery <br> ❑ Factitious diarrhea (eating disorders, laxative ingestion, [[secondary gain]] or [[malingering]]) <br> ❑ Systemic disease ([[cancer]], [[diabetes]], [[HIV]], [[hyperthyroidism]]) <br>
| |
| ----
| |
| '''Elicit the epidemiological factors:'''<br>
| |
| ❑ Travel before the onset of illness <br>
| |
| ❑ Exposure to contaminated food or water <br>
| |
| ❑ Illness in other family members </div>}}
| |
| {{familytree | | | |!| | | }}
| |
| {{familytree | | | C01 | | | C01=<div style="float: left; text-align: left; height: 29em; width: 30em; padding:1em;"> '''Examine the patient:'''<br>
| |
| '''Assess the volume status:''' <br>
| |
| ❑ General condition <br>
| |
| ❑ Thirst <br>
| |
| ❑ [[Pulse]] <br>
| |
| ❑ [[Blood pressure]] <br>
| |
| ❑ Eyes <br>
| |
| ❑ Mucosa
| |
| ----
| |
| '''Perform a general physical exam:'''<br>
| |
| ❑ Skin ([[flushing]], [[rash]]es or dermatographism) <br> ❑ Oral cavity (ulcers) <br> ❑ Cardiovascular system (murmur)<br> ❑ Respiratory system (wheezing) <br> ❑ [[Thyroid]] (mass) <br> ❑ [[Abdomen]] ([[ascites]], [[hepatomegaly]], mass or tenderness) <br> ❑ Anorectal ([[Abscess]], blood, [[fistula]] or sphincter competence) <br> ❑ Extremities ([[edema]]) </div>}}
| |
| {{familytree | | | |!| | | | }}
| |
| {{familytree | | | D01 | | | | D01=<div style="float: left; text-align: left; height: 12em; width: 30em; padding:1em;"> '''Order routine laboratory tests:'''
| |
| ❑ [[CBC|CBC and differential]] <br> ❑ [[ESR]] <br> ❑ [[Serum electrolytes]]<br> ❑ Total serum [[protein]] and [[albumin]] <br> ❑ [[Thyroid function tests]] <br> ❑ [[Urinalysis]] <br>
| |
| </div>}}
| |
| {{familytree | | | |!| | | | }}
| |
| {{familytree | | | D10 | | | | D10= <div style="float: left; text-align: left"> '''Start altered diet:'''<br> ❑ Stop lactose products <br> ❑ Avoid alcohol and high osmolar supplements <br> ❑ Drink 8-10 large glasses of clear fluids (fruit juices, soft drinks etc) <br> ❑ Eat frequent small meals (rice, potato, banana, pastas etc) <br>
| |
| ----
| |
| ❑ '''Start [[oral rehydration therapy]] or [[intravenous fluids]] depending on the hydration status'''</div>}}
| |
| {{familytree | | | |!| | | | | }}
| |
| {{familytree | | | D02 | | | | | D02 = '''Any specific obvious diagnosis through history and examination?'''}}
| |
| {{familytree | |,|-|^|-|.| | }}
| |
| {{familytree | D03 | | D04 | | D03= <div style="float: left; text-align: left; width: 30em; padding:1em;">Yes </div>| D04=<div style="float: left; text-align: left; width: 30em; padding:1em;">No </div>}}
| |
| {{familytree | |!| | | |!| | }}
| |
| {{familytree | D05 | | |!| | D05= <div style="float: left; text-align: left; height: 22em; width: 30em; padding:1em;"> '''Chronic infection (outbreaks or endemic areas)'''<br> ❑ Trial of oral [[metronidazole]] 500 mg TID for 5 days for protozoal diarrhea<br> ❑ Oral [[ciprofloxacin]] 500 mg BD X 3 days for enteric bacterial diarrhea
| |
| -----
| |
| '''Medication induced:''' <br>
| |
| ❑ Discontinuation of the drug
| |
| -----
| |
| '''Irritable bowel syndrome''' (chronic abdominal pain and altered bowel habits in the absence of any organic disorder)<br>
| |
| ❑ Trial of antispasmodic agents (oral [[dicyclomine]] 20 mg QID),OR <br>
| |
| ❑ [[Tricyclic antidepressant|TCA's]]([[amitriptyline]] 10-25 mg OD), OR <br>
| |
| ❑ [[SSRI]] ([[fluoxetine]] 20-40 mg OD), OR <br>
| |
| ❑ [[Rifaximin]]</div>}}
| |
| {{familytree | |!| | | |!| | }}
| |
| {{familytree | E01 | | |!| | E01= No resolution of the diarrhea}}
| |
| {{familytree | |`|-|v|-|'| | }}
| |
| {{familytree | | | F01 | | | F01=<div style="float: left; text-align: left; line-height: 150% "> '''Order stool analysis:'''<br>
| |
| ❑ [[Diarrhea laboratory findings#Fecal Weight|Stool weight]] <br> ❑ [[Diarrhea laboratory findings#Stool Osmotic Gap|Stool electrolytes and fecal osmotic gap]] <br> ❑ [[Diarrhea laboratory findings#Fecal pH|Stool pH]] <br> ❑ [[Diarrhea laboratory findings#Occult Blood|Fecal occult blood testing]] <br> ❑ [[Diarrhea laboratory findings#White Blood Cells|Stool WBC's]] <br> ❑ Stool fat: [[Diarrhea laboratory findings#Fecal Fat Concentration and Output|Quantitative]] / [[Diarrhea laboratory findings#Sudan Stain for Fat|Sudan stain]] <br> ❑ [[Diarrhea laboratory findings#Analysis for Laxatives|Laxative screen]] </div>}}
| |
| {{familytree/end}}
| |
| This management is as per the American Gastroenterological Association guidelines for the evaluation and management of chronic diarrhea.<ref name="pmid10348831">{{cite journal| author=| title=American Gastroenterological Association medical position statement: guidelines for the evaluation and management of chronic diarrhea. | journal=Gastroenterology | year= 1999 | volume= 116 | issue= 6 | pages= 1461-3 | pmid=10348831 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10348831 }} </ref>
| |
| <br>
| |
|
| |
| ===Additional Management===
| |
| It is important to differentiate [[chronic diarrhea]] based on the kind of [[diarrhea]] that is produced. Chronic diarrhea can be subdivided into three major types; [[Watery diarrhea|watery]], [[Steatorrhea|fatty]], [[inflammatory]]. Watery chronic diarrhea can then further be sub-divided into [[osmotic]] or [[Secretory component|secretory]] [[diarrhea]].<ref name="pmid10348832">{{cite journal| author=Fine KD, Schiller LR| title=AGA technical review on the evaluation and management of chronic diarrhea. | journal=Gastroenterology | year= 1999 | volume= 116 | issue= 6 | pages= 1464-86 | pmid=10348832 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=10348832 }} </ref><ref name="LacyMearin2016">{{cite journal|last1=Lacy|first1=Brian E.|last2=Mearin|first2=Fermín|last3=Chang|first3=Lin|last4=Chey|first4=William D.|last5=Lembo|first5=Anthony J.|last6=Simren|first6=Magnus|last7=Spiller|first7=Robin|title=Bowel Disorders|journal=Gastroenterology|volume=150|issue=6|year=2016|pages=1393–1407.e5|issn=00165085|doi=10.1053/j.gastro.2016.02.031}}</ref>
| |
| *The [[stool]] [[osmotic]] gap is a calculation performed to distinguish among different causes of diarrhea.
| |
| *290 − 2 * (stool Na + stool K)<ref name="pmid8159195">{{cite journal| author=Topazian M, Binder HJ| title=Brief report: factitious diarrhea detected by measurement of stool osmolality. | journal=N Engl J Med | year= 1994 | volume= 330 | issue= 20 | pages= 1418-9 | pmid=8159195 | doi=10.1056/NEJM199405193302004 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8159195 }} </ref>
| |
| *A low stool osmolic gap can imply secretory diarrhea, while a high gap can imply osmotic diarrhea.<ref name="pmid3994188">{{cite journal| author=Shiau YF, Feldman GM, Resnick MA, Coff PM| title=Stool electrolyte and osmolality measurements in the evaluation of diarrheal disorders. | journal=Ann Intern Med | year= 1985 | volume= 102 | issue= 6 | pages= 773-5 | pmid=3994188 | doi= | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=3994188 }} </ref>{{familytree/start}}
| |
| {{familytree | | | | | | | | | | | A01 | | | | | | | | | | | | | | | | | |A01=❑ '''Classify diarrhea by the results of the stool analysis:'''}}
| |
| {{familytree | | | |,|-|-|-|-|-|v|-|-|-|v|-|-|-|.| | | | | | | | | | }}
| |
| {{familytree | | | E01 | | | | E02 | | E03 | | E04 | | | | | | | | | | | E01 = Stool osmotic gap >50 mOsm/kg | E02 = Stool osmotic gap <50 mOsm/kg | E03 = Fecal occult blood (+), WBC (+), [[lactoferrin]] (+), calprotectin(+) | E04 = Fecal fat (+)}}
| |
| {{familytree | | | |!| | | | | |!| | | |!| | | |!| | | | | | | |}}
| |
| {{familytree | | | E01 | | | | E02 | | E03 | | E04 | | | | | | | | | | |E01= '''Osmotic diarrhea''' | E02= '''Secretory diarrhea'''|E03= '''Inflammatory diarrhea''' |E04= '''Fatty diarrhea''' }}
| |
| {{familytree | | | |!| | | | | |!| | | |!| | | |!| | | | | | | |}}
| |
| {{familytree | | | E05 | | | | |!| | | |!| | | |!| | | | | | | |E05= ❑ Check the pH of the stool}}
| |
| {{familytree | |,|-|^|-|.| | | |!| | | |!| | | |!| | | | | | | | | | | | }}
| |
| {{familytree | F01 | | F02 | | F03 | | F04 | | F05 | | | | | | | | | | | |F01= '''Low pH'''<br> <div style="float: left; text-align: left">❑ Evaluate for [[malabsorption|carbohydrate malabsorption]]</div> | F02= '''High pH''' <br> <div style="float: left; text-align: left">❑ Evaluate for ingestion of magnesium or antacids <br> ❑ Evaluate for laxative abuse </div>|F03= <div style="float: left; text-align: left">'''1. Exclude infection by any/combination of the following tests:'''
| |
| ----
| |
| ❑ [[Diarrhea laboratory findings#Fecal Cultures|Stool culture]] <br> ❑ Microscopic evaluation for ova and [[parasite]]s <br> ❑ Stool antigen test for [[Giardia]] <br> ❑ [[Diarrhea laboratory findings#Upper Tract Endoscopy|Small bowel aspirate]] or [[Diarrhea laboratory findings#Tests for Bacterial Overgrowth|breath H2 test]] to rule out bacterial overgrowth </div>
| |
| |F04=<div style="float: left; text-align: left"> '''1. Exclude structural disease by any/combination of the following tests:'''
| |
| ----
| |
| ❑ [[Diarrhea laboratory findings#Radiography|Small bowel radiographs]] <br> ❑ [[Diarrhea laboratory findings#Sigmoidoscopy and Colonoscopy|Sigmoidoscopy or colonoscopy with biopsy]] <br> ❑ [[Diarrhea laboratory findings#Radiography|CT abdomen]] <br> ❑ [[Diarrhea laboratory findings#Upper Tract Endoscopy|UGI scopy and small bowel biopsy]] <br>
| |
| </div> |F05=<div style="float: left; text-align: left; line-height: 150% "> '''1. Exclude structural disease by any/combination of the following tests'''
| |
| ----
| |
| ❑ [[Diarrhea laboratory findings#Radiography|Small bowel radiographs]] <br> ❑ [[Diarrhea laboratory findings#Radiography|CT abdomen]] <br> ❑ [[Diarrhea laboratory findings#Upper Tract Endoscopy|Small bowel biopsy and aspirate for quantitative culture]] <br>
| |
| </div> }}
| |
| {{familytree | |!| | | |!| | | |!| | | |!| | | |!| | | | | | | | | | | | }}
| |
| {{familytree | G01 | | G06 | | G02 | | G03 | | G04 | | | | | | | | | | |G01= ❑ Take a careful dietary history <br> ❑ Order [[lactose intolerance laboratory findings|breath H2 test (lactose), OR ❑ Order lactase measurement in a mucosal biopsy]] | G06 = ❑ Order stool alkanization test <br> ❑ Order chromatographic and chemical tests | G02=<div style="float: left; text-align: left; line-height: 150% "> '''2. Exclude structural disease by any/combination of the following tests:'''
| |
| ----
| |
| ❑ [[Diarrhea laboratory findings#Radiography|Small bowel radiographs]] <br> ❑ [[Diarrhea laboratory findings#Sigmoidoscopy and Colonoscopy|Sigmoidoscopy or colonoscopy with biopsy]] <br> ❑ [[Diarrhea laboratory findings#Radiography|CT abdomen]] <br> ❑ [[Diarrhea laboratory findings#Upper Tract Endoscopy|Biopsy of the proximal small bowel mucosa]] <br>
| |
| </div> |G03=<div style="float: left; text-align: left; line-height: 150% "> '''2. Exclude infection by any/combination of the following tests:'''
| |
| ----
| |
| ❑ [[Diarrhea laboratory findings#Fecal Cultures|Stool culture]]: Standard [[Aeromonas]], [[Plesiomonas]], [[Tuberculosis]] etc <br> ❑ Stool for ova and [[parasite]]s <br> ❑ [[Clostridium difficile laboratory findings|Clostridium toxin assay]] <br> ❑ Other specific test (Serology, [[ELISA]], [[immunofluorescence]] to rule out virus and parasites) <br>
| |
| </div> |G04=<div style="float: left; text-align: left; line-height: 150% ">'''2. Exclude exocrine pancreatic insufficieny by any/combination of the following tests:'''
| |
| ----
| |
| ❑ [[Zollinger-Ellison syndrome laboratory tests|Secretin test]] <br> ❑ Stool chymotrypsin activity <br> ❑ [[Bentiromide|Bentiromide test]] <br> ❑ Others ([[Diarrhea laboratory findings#Tests for Bacterial Overgrowth|D-xylose absorption tests / Schilling test]]) <br>
| |
| </div> }}
| |
| {{familytree | |!| | | |!| | | |!| | | |!| | | |!| | | | | | | | | | | | }}
| |
| {{familytree | |!| | | |!| | | H01 | | |!| | | |!| | | | | | | | | |H01=<div style="float: left; text-align: left; line-height: 150% "> '''3. Order selective testing:'''
| |
| ----
| |
| ❑ Cholestyramine test for bile acid diarrhea <br> ❑ Plasma peptides ([[Gastrin]], [[calcitonin]], [[vasoactive intestinal polypeptide]] or [[somatostatin]]) <br> ❑ Urine (5-hydroxyindole acetic acid, [[metanephrine]] or [[histamine]]) <br> ❑ Others ([[TSH]], [[ACTH stimulation test]], serum protein electrophoresis or serum [[immunoglobulins]]) <br> </div> }}
| |
| {{familytree | |!| | | |!| | | |!| | | |!| | | |!| | | | | | | | | | }}
| |
| {{familytree | |`|-|-|-|^|-|-|-|+|-|-|-|^|-|-|-|'| | | | | | | | | | }}
| |
| {{familytree | | | | | | | | | G05 | | | | | | | | | | | | | | | | | | | | | | G05 = Confirmatory diagnosis}}
| |
| {{familytree | | | | | | | |,|-|^|-|.| | | | | | | | | | | | | | | | | | | }}
| |
| {{familytree | | | | | | | D01 | | D02 | | | | | | | | | | | | | | | | | | | D01= Yes | D02= No }}
| |
| {{familytree | | | | | | | |!| | | |!| | | | | | | | | | | | | | | | | | | }}
| |
| {{familytree | | | | | | | D05 | | |!| | | | | | | | | | | | | | | | | | | | D06 = Significant response and recovery | D05 = Specific treatment per results and symptomatic treatment}}
| |
| {{familytree | | | | | | | |!| | | |!| | | | | | | | | | | | | }}
| |
| {{familytree | | | | | | | D02 | | |!| | | | | | | | | | | | | | D02 = No response}}
| |
| {{familytree | | | | | | | |`|-|v|-|'| | | | | | | | | | | | | | | | | | | }}
| |
| {{familytree | | | | | | | | | G03 | | | | | | | | | | | | | | | | | | | | | |G03=<div style="float: left; text-align: left; line-height: 150% "> '''Administer empirical therapy'''<br>
| |
| ❑ Adequate hydration <br> ❑ Opiates or [[octreotide]] <br>
| |
| </div> }}
| |
| {{familytree/end}}
| |
|
| |
|
| |
|
| |
| '''Watery''' | | '''Watery''' |
|
| |
| *'''Secretory''' (often nocturnal; unrelated to food intake; fecal osmotic gap < 50 mOsm per kg*) | | *'''Secretory''' (often nocturnal; unrelated to food intake; fecal osmotic gap < 50 mOsm per kg*) |
| **[[Alcoholism]] | | **[[Alcoholism]] |