Table of Contents
What does high stool osmolality mean?
A fecal sodium concentration of greater than 150 mmol/L and an osmolality of greater than 400 mOsm suggest contamination of stool with concentrated urine. A fecal osmolality of less than 250 mOsm suggests contamination of stool with hypoosmotic urine or water.
How is factitious diarrhea diagnosed?
Factitious diarrhea has traditionally been diagnosed by evaluating stools for laxatives. We recently studied two patients with chronic unexplained diarrhea who were found to have diluted their stool samples.
Why does osmotic diarrhea have a high osmotic gap?
High osmotic gap (>100 mOsm/kg) causes of osmotic diarrhea include celiac sprue, chronic pancreatitis, lactase deficiency, lactulose, osmotic laxative use/abuse, and Whipple’s disease. Low osmotic gap (<50 mOsm/kg) causes of secretory diarrhea include toxin-mediated causes (cholera, enterotoxigenic strains of E.
What causes factitious diarrhea?
Factitious diarrhea may be due to a self-induced true increase in stool volume or the creation of an apparent increase in stool volume by the addition of various substances to the stool.
What is normal stool osmolality?
Stool osmolality is measured in milliosmoles per kilogram (mOsm/kg). It normally ranges from 275 to 295 mOsm/kg. Stool osmolality less than 250 mOsm/kg may suggest factitious diarrhea.
How do you test for osmotic diarrhea?
Another way to clinically differentiate osmotic diarrhea from secretory diarrhea is by calculating the fecal osmotic gap. The fecal osmotic gap is calculated by adding the stool sodium and potassium concentration, multiplying by 2, and subtracting this amount from 290 mmol/L.
How can you tell the difference between osmotic diarrhea and secretory diarrhea?
Watery diarrhea can be further classified as osmotic or secretory in origin. Osmotic diarrhea is due to the ingestion of poorly absorbed ions or sugars. Secretory diarrhea is due to disruption of epithelial electrolyte transport.
What are examples of osmotic diarrhea?
Osmotic diarrhea is usually due to ingestion of poorly absorbed cations (eg, magnesium) or anions (eg, phosphate, or sulfate), which are often contained in laxatives and antacids, or to carbohydrate malabsorption from ingestion of poorly absorbed sugars or sugar alcohols (eg, sorbitol or xylitol).
How do you prove factitious disorders?
Diagnosis is based on objectively identifying symptoms that are made up, rather than the person’s intent or motivation for doing so. A doctor may suspect factitious disorder when: The person’s medical history doesn’t make sense. No believable reason exists for an illness or injury.
What is an example of factitious disorder?
An example of a psychological factitious disorder is mimicking behavior that is typical of a mental illness, such as schizophrenia. The person may appear confused, make absurd statements, and report hallucinations (the experience of sensing things that are not there; for example, hearing voices).
Is factitious disorder conscious?
Factitious disease is defined as the intentional production (or feigning) of disease in oneself to relieve emotional distress by assuming the role of a sick person. Although the self-induction of disease is a conscious act, the underlying motivation is usually unconscious.
What are the two types of factitious disorders?
Factitious disorder with both psychological and physical symptoms: People with this disorder produce symptoms of both physical and mental illness. Factitious disorder not otherwise specified: This type includes a disorder called factitious disorder by proxy (also called Munchausen syndrome by proxy).
When should you suspect factitious disorder?
A doctor may suspect factitious disorder when: The person’s medical history doesn’t make sense. No believable reason exists for an illness or injury. The illness does not follow the usual course.
What are some of the possible symptoms of factitious disorder?
Factitious disorder symptoms involve mimicking or producing illness or injury or exaggerating symptoms or impairment to deceive others….How those with factitious disorder fake illness
- Exaggerating existing symptoms.
- Making up histories.
- Faking symptoms.
- Causing self-harm.
- Tampering.
What is the essential diagnostic feature of factitious disorder?
Diagnostic criteria for factitious disorder Intentional induction or falsification of physical or psychological signs or symptoms. The individual presents themselves as ill, impaired or injured to others. The deceptive behavior persists even in the absence of external incentives or rewards.
How do you diagnose factitious disorder?
A doctor may suspect factitious disorder when:
- The person’s medical history doesn’t make sense.
- No believable reason exists for an illness or injury.
- The illness does not follow the usual course.
- There is a lack of healing for no apparent reason, despite appropriate treatment.
What does my stool osmolality result mean?
Ask your healthcare provider what your test results mean for you. Stool osmolality is measured in milliosmoles per kilogram (mOsm/kg). It normally ranges from 275 to 295 mOsm/kg. Stool osmolality less than 250 mOsm/kg may suggest factitious diarrhea.
How do you measure electrolytes and osmolality?
Electrolytes and osmolality are usually measured not to diagnose factitious disease but to distinguish osmotic from secretory diarrhea by calculating the osmotic gap (the difference between stool osmolality and twice the sum of the stool sodium and potassium concentrations)8.
How is laxative abuse detected in a stool sample?
Laxative use or abuse can be detected by measuring stool electrolytes, magnesium, and phenolphthalein and by chromatographic analysis of stool and urine specimens. Factitious diarrhea may not be discovered, however, unless stool osmolality is also measured.
What are the causes of factitious diarrhea?
Surreptitious abuse of laxatives and ingestion of drugs whose laxative properties are not recognized are leading causes of chronic diarrhea in patients referred to university hospitals for evaluation. Factitious diarrhea has traditionally been diagnosed by evaluating stools for laxatives.