Urinalysis (Urine dipstick testing)

What equipment do you need?

Alcohol gel

Gloves

Apron

Dipsticks

Urine sample

Paper towels

What does straw-coloured urine indicate?

This is normal!

What does dark concentrated urine indicate?

Suggests the individual is dehydrated

What does red urine indicate?

Can be caused by the presence of blood in the urine (macroscopic haematuria), porphyria (group of disorders that result from build up of porphyrin and this is essential for the function of haemaglobin), drugs such as rifampicin and certain foods (e.g. beetroot)

What does brown urine indicate?

Can be caused by the presence of bile pigments (e.g. jaundice) or myoglobin (e.g. rhabdomyolysis)

Some antimalarial medication, such as chloroquine

What does clear urine suggest?

This is normal!

What does cloudy urine with sediment suggest?

UTI, renal stones, high protein content (e.g. nephrotic syndrome)

What does frothy urine suggest?

Associated with significant proteinuria (e.g. nephrotic syndrome)

What does offensive odour show?

Suggestive of urinary tract infection

What does sweet odour show?

Suggestive of glycosuria (e.g. diabetes mellitus)

What are the 9 steps of the procedure

1. Check the expiry date of the urinalysis dipstick.

2. Remove a dipstick from the container whilst avoiding touching the reagent squares.

3. Replace the container lid to prevent oxidisation of the remaining dipsticks.

4. Insert the dipstick into the urine sample, ensuring all reagent squares are fully immersed.

5. Remove the dipstick immediately and tap off any residual urine using the edge of the container, making sure to hold the dipstick horizontally to avoid cross-contamination of the reagent squares.

6. Lay the dipstick flat on a paper towel.

7. Use the urinalysis guide on the side of the testing strip container to interpret the findings. Different reagent squares on the strip need to be interpreted at different times, so ensure you interpret the correct test at the appropriate time interval (e.g. 60 seconds for protein).

8. Once you have interpreted all of the tests, discard the strip into the clinical waste bin along with your PPE.

9. Wash your hands.

What does urinalysis test for?

Glucose

Bilirubin

Ketones

Specific gravity

Blood

Protein

Nitrites

Urobilinogen

Leukocyte esterase

Glucose present in the urine (glycosuria) indicates what?

Diabetes mellitus

Renal tubular disease

Some diabetic medications (SGLT2 Inhibitors)

What does the presence of bilirubin suggest?

Increased serum levels of conjugated bilirubin which occur as a results of biliary obstructions (e.g. pancreatic cancer)

The presence of ketones suggests?

Increased fatty acid metabolism which occurs in starvation and in conditions such as diabetic ketoacidosis

What is specific gravity?

Indicates the amount of solute dissolved in the urine

Causes of low specific gravity

Are conditions that results in the production of dilute urine such as diabetes insipidus and acute tubular necrosis

Causes of high specific gravity

Dehydration, glycosuria (e.g. diabetes mellitus) and proteinuria (e.g. nephrotic syndrome)

Causes of low pH

Starvation, diabetic ketoacidosis, metabolic acidosis

Causes of high pH

UTI, conditions that cause metabolic alkalosis (e.g. vomiting) and medications (e.g. diuretics)

What does the blood reagent square indicate?

Amount of red blood cells, haemoglobin and myoglobin in the urine

The presence of RBC, haemoglobin and myoglobin indicates what?

UTI, renal stones, injury to the urinary tract, myoglobinuria (rhabdomyolysis), nephritic syndrome and malignancy of the urinary tract

What are the causes of proteinuria (protein present in the urine)

Nephrotic syndrome and chronic kidney disease

What are Nitrites

Breakdown product of gram-negative organisms (such as E.coli)

What does it mean if nitrates are present?

Suggest UTI

What is Urobilinogen?

Is a byproduct of bilirubin breakdown in the intestine

High levels of urobilinogen can be caused by what?

Haemolysis (e.g. haemolytic anaemia, malaria)

Low levels of urobilinogen can be caused by what?

Biliary obsruction

What is Leukocyte esterase?

Is an enzyme produced by neutrophils and therefore positive it indicates the presence of WBC in the urine

What causes a positive leukocyte esterase?

UTI and any conditions that could result in haematuria (is the presence of blood in the urine)

What further investigations would you do if leukocytes and nitrates were present?

Indicates UTI

Microscopy and culture to identify pathogenic organisms

What further investigations if there is glucose present?

Indicates diabetes mellitus

Capillary blood glucose and serum HbA1C

What further investigations if glucose and ketones and low pH present in the urine

Admit to hospital as probably has ketoacidiosis

Further investigations = serum blood glucose, venous blood gas

Treatment = insulin, glucose and potassium infusion

What further investigations if raised specific gravity and proteinuria

Is suggestive of nephrotic syndrome

You would do U&Es to assess renal function as well as microscopy and culture to rule out UTI

What further investigation for if blood present in the urine

Microscopy and culture (UTI), full blood count, U&Es (glomerulonephritis), CT KUB (renal calculi) and cystoscopy (bladder malignancy)