RENAL - Urinalysis and Catheterisation

Question 1

What does absence or presence of bilirubin in the urine indicate?

Answer 1

• Absence is normal
• Presence indicates increased serum levels of conjugated bilirubin - occurs in conditions such as biliary obstructions (e.g pancreatic cancer)

Question 1

What would presence or absence of glucose indicate in the urine?

Answer 1

• Absence is normal
• Causes of glycosuria include diabetes mellitus, renal tubular disease and some diabetic medications (e.g. SGLT2 inhibitors).

Question 2

What produces ketones and what does its presence or absence in urine indicate?

Answer 2

• Breakdown product of fatty acid metabolism
• Absence is normal
• Presence suggests increased fatty acid metabolism e.g during starvation or conditions such as DKA

Question 3

What is specific gravity and what does it indicate if it is low or high?

Answer 3

• Amount of solute dissolved in urine
• LOW - Conditions resulting in production of dilute urine e.g diabetes insipidus and acute tubular necrosis
• RAISED - dehydration, glycosuria and proteinuria

Question 4

What do high and low urinary pHs indicate?

Answer 4

• Causes of low urinary pH include starvation, DKA and other conditions that cause metabolic acidosis (e.g. sepsis).
• Causes of raised urinary pH include urinary tract infection, conditions that cause metabolic alkalosis (e.g. vomiting) and medications (e.g. diuretics).

Question 5

What does absence or presence of blood in the urine indicate?

Answer 5

• Absence is normal
• Presence indicates UTIs, renal stones, urinary tract injuries, myoglobinuria (rhabdomyolysis), nephritic syndrome and malignancy of the urinary tract

Question 6

What does absence or presence of protein in the urine indicate?

Answer 6

• Absence is normal
• Presence indicates nephrotic syndrome or CKD

Question 7

What causes nitrites to be present in urine and what does its absence or presence indicate?

Answer 7

• Absence is normal
• Presence suggestive of UTIs

Question 8

How does urobilinogen form and what do increased or decreased levels of it in the urine indicate?

Answer 8

• INCREASED - caused by haemolysis e.g malaria or haemolytic anaemia
• DECREASED - biliary obstruction

Byproduct of bilirubin breakdown in the intestine - excreted in urine

Question 9

What is leukocyte esterase and what does it mean if it is positive or negative in urine?

Answer 9

• Produced by neutrophils
• POSITIVE - indicates presence of white blood cells in urine - includes UTIs or conditions resulting in haematuria
• NEGATIVE - normal

Question 10

What does presence of leukocytes and nitrites in urine indicate and what would further investigations include?

Answer 10

• UTI
• Microscopy and cultures to identify pathogenic organisms

Question 11

What does presence of glucose in urine indicate and what would further investigations include?

Answer 11

• Diabetes mellitus
• Further investigation with capillary blood glucose and HbA1C

Question 12

What does presence of glucose and ketones, along with low urinary pH, in urine indicate and what would further investigations include?

Answer 12

DKA
- Hospital admissions - for further investigations (e.g. serum blood glucose, venous blood gas) and treatment (e.g. insulin, glucose and potassium infusion).

Question 13

What does raised specific gravity and proteinuria indicate and what would further investigations include?

Answer 13

NEPHROTIC SYNDROME
- U&Es - assess renal function
- Microscopy and culture to rule out UTIs

Question 14

What does haematuria indicate and what would further investigations include?

Answer 14

Possible further investigations could include microscopy and culture (UTI), full blood count, U&Es (glomerulonephritis), CT KUB (renal calculi) and cystoscopy (bladder malignancy).