Stool Sample/Temp./Urine

Is a screening tool, NOT a diagnostic


Causes of False Positive:

  • Red Meet (beef, lama, liver)

  • Medications

    • Aspririn use > 325 mg a day

    • NSAIDs

    • Corticosteroids

    • Anticoagulants

    • Chemotherapy

  • Excess Alcohol



Causes of False Negative

  • Vitamin C (ascorbic acid)

    • Avoid excess of 250 mg a day

Found in Supplements, fruit juices, iron supplements



Patient Teaching: Drug and Diet Guidelines

7 days before beginning test and during sample collection

  • Avoid NSAIDS

  • Acetaminophen can be taken as needed


3 days before beginning test during sample collection

  • Avoid red meat

  • Avoid excess vitamin c


How to apply a stool sample: THIN SMEAR

Specific Gravity

Between 1.002 and 1.035 on a random sample is normal if kidney function is normal.

  • Decreased: < 1.005

    • Inability to concentrate urine or excessive hydration (volume resuscitation with IV fluids)

  • Fixed: 1.010

    • Any measurement below this range indicates hydration and any measurement above it indicates relative dehydration

  • Increased: > 1.035

    • Increased specific gravity indicates a concentrated urine with a large volume of dissolved solutes; dehydration

pH

The kidneys play an important role in acid-base regulation within the body to maintain a normal urinary pH range between 4.5-8.0.

  • The pH level might indicate a kidney or urinary tract disorder

  • Control of pH is important in the management of several diseases, including bacteriuria, renal calculi, and drug therapy

  • High Urinary pH (Alkali Urine)

    • Vegetarian diet, low carbohydrate diet, or ingestion of citrus fruit

  • Low Urinary pH (Acidic urine)

    • High protein diet or fruits such as cranberries

Protein

Normal daily protein excretion should not exceed 150mg/24 hours or 10mg/100mL.

  • Low levels of protein in urine are typical

  • Small increases in protein in urine usually aren't a cause for concern, but larger amounts might indicate a kidney problem

Leucocytes (White cell count)

  • Determines the presence of white blood cells in the urine (pyuria) by detecting leucocyte esterase activity

  • A positive leucocyte esterase test correlates well with pyuria (Urinary Tract Infection)

Nitrites

  • A positive nitrite test is a surrogate marker of bacteriuria

Blood

  • To detect haemolysed and non-haemolysed blood in the urine

  • It may be a sign of kidney damage, infection, kidney or bladder stones, kidney or bladder cancer, or blood disorders

Ketones

  • Ketonuria is associated with low carbohydrate (high fat/protein) diets, starvation, diabetes, alcoholism, eclampsia, and hyperthyroidism

  • Also associated with an overdose of insulin, isoniazid, and isopropyl alcohol

Glucose

  • The amount of sugar (glucose) in urine is typically too low to be detected

  • Any detection of sugar on this test usually calls for follow-up testing for diabetes

Bilirubin

  • Bilirubin is a product of red blood cell breakdown. Usually, bilirubin is carried in the blood and passes into your liver, where it's removed and becomes part of bile

  • Is not present in the urine of normal healthy individuals

  • The presence of bilirubinuria may be an early indicator of liver disease and occur before the clinical signs of jaundice develop

Urobilinogen

  • Is normally present in the urine in low concentrations (0.2-1.0 mg/dL)

  • Most urobilinogen is excreted in the feces or transported back to the liver and converted into bile