Urinalysis Overview

Parameter Expected Normal Result and differential diagnosis False Positive/

False increase

False Negative/
False Decrease
Colour Yellow
Straw-yellow
pH

Range (4.5-8.0)

5.5 – 6.5 Alkali:
- Diet (Vegetarian, low carbohydrate diet, lots of citrus fruit)
- Systemic alkalosis (metabolic or respiratory)
- RTA I, Fanconi, UTI (most)
- Salicylate OD, antibiotics, acetazolomideAcid:
- Diet (high protein, cranberries)
- Systemic acidosis
- DM, DKA, starvation, COPD, diarrhoea, malabsorption
- Phenylketonuria, renal TB, alkaptonuria
Stale sample left standing (ammoniacal)
Specific Gravity (g/mL) 1.002 – 1.030 <1.005 – DI, ATN, PN, Acute GN

1.010 – CRF, chronic GN

>1.030 – Ddehydration, SIADH, adrenal insufficiency

Alkaline urine - Proteinuria
- Glucosuria
- IV contrast
- Colloid
Protein Negative to trace Renal: Increased renal tubular secretion, increased glomerular filtration (glomerular disease), nephrotic syndrome, pyelonephritis, glomerulonephritis, malignant hypertension

CVS: Benign HT, CCF, SBE

Other: Pre-eclampsia, gout, orthostatic proteinuria, increased plasma protein (myeloma), electric current injury, K+ depletion, Cushing’s syndrome

Drugs: Aminoglycosides, gold, amphotericin, NSAID, sulphonamides, penicillins

Concentrated urine (UO<2.5L/day)

Alkaline urine (pH >7.5)

Trace residue of bleach

Aceazolomide, cephalosporins, NaHCO3

Dilute urine (UO >5.0 litres/day)

Acidic urine (pH <5)

Bence Jones globulin associated with multiple myeloma, lymphoma and macroglobulinaemia is NOT detected by dipstick urinalysis

Leucocytes

<15, 15, 75, 125, 500

(leu/μL )

or

-, +, ++, +++

Negative Pyuria Contaminated specime

Ttrichomonas vaginalis,

Drugs or foods that colour the urine red

Intercurrent antibiotic therapy (e.g. gentamicin, tetracycline and cephalosporins)

Gglycosuria

Proteinuria,

High specific gravity.

Low bacteria count UTI (especially in women)

Nitrite Negative Bacterial urinary infection (usually associated with Gram-negative bacteria) Drugs or foods that colour the urine red. Ascorbic acid

Certain bacteria such as S. saprophyticus, acinetobacter and most enterococci

Blood Negative Haematuria: trauma, infection, inflammation, infarction, calculi, neoplasia, clotting disorders or chronic infection.

Haemaglobinuria (intravascular haemolysis)

Myoglobinuria (crush injury, electrocution, rhabdomyolysis)

Hypochlorite bleach
Ketones

<5, 5, 15, 50, 150

mg/dL

or

-, +, ++

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

Overdose of insulin, isoniazid and isopropyl alcohol

Heavily pigmented urine. Captopril, L-dopa, salicylates, phenothiazines Underestimate the presence of ketonaemia (beta-hydroxybutyric acid can not be assessed on dipstick)
Bilirubin Negative Raised conjugated bilirubinaemia (with bilirubinuria) is associated with hepatocellular disease, cirrhosis, viral and drug induced hepatitis, biliary tract obstruction (e.g. choledocholithiasis), pancreatic causes of obstructive jaundice (e.g. carcinoma of the head of the pancreas) and recurrent idiopathic jaundice of pregnancy

Inherited condition: Dubin-Johnsons syndrome, Rotor’s syndrome

Phenothiazines Ascorbic acid (vitamin C)

Aged sample (conjugated bilirubin hydrolses to unconjugated bilirubin at room temperature)

Rifampicin

Exposure to UV light (converts bilrubin to biliverdin)

Urobilinogen

mg/dL

0.2-1.0 mg/dL

<17micromol/L

Increased: cirrhosis, infective hepatitis, extravascular haemolysis, haemolytic anaemia, pernicious anaemia, malaria, and hepatitis secondary to infectious mononucleosis

Decreased: or absent in obstructive jaundice and elevated levels of bilirubinuria

Glucose Negative Hyperglycaemia associated with diabetes, cystinosis, Cushings syndrome or thyrotoxicosis. Liver disease (e.g. Wilsons disease)

Renal: Reduced ‘renal threshold’, renal tubular disease and pregnancy

Drugs: cephalosporins, penicillins, nitrofurantoin, methyldopa, tetracycline, lithium, carbemazepine, phenothiazines, steroids and thiazides

Hydrogen peroxide or bleach Ascorbic acid (vitamin C) or fruit juice. Some dipsticks are affected by increased specific gravity and ketonuria
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