Urinalysis

Question 1

Why undertake urinalysis?

Answer 1

Non-invasive and reliable for diagnosing signs and symptoms of disease in early stages

Tests both physical characteristics and composition

Immediate results using reagent strip

Enables monitoring and deviations

Question 2

MSSU

Answer 2

Middle part of urine

Question 3

Physical characteristics of urine

Answer 3

Colour - pale straw to amber depending on concentration

Clarity - clear when freshly voided

Odour - characteristic inoffensive odour

Question 4

Composition - what is the ph of urine

Answer 4

4.5 - 8

Question 5

Composition - what is specific gravity of urine

Answer 5

1.003 - 1.030

Question 6

Composition - what is urine made up of

Answer 6

Mainly water 96% with dissolved substances 4%

Urea 2%, Uric acid, sodium, potassium, phosphates, sulphites, oxylates, chlorides

Also cellular components, epithelial cells, leukocytes

Question 7

Different colours of urine

Answer 7

Dark yellow = concentrated
Pale = dilute
Very dark yellow/brown/frothy bilirubinuria

Question 8

Ph of urine

Answer 8

4.5-8

Low ph = acidic, may predispose to the formulation of calculi in bladder/kidney

Question 9

Proteinuria

Answer 9

Indicates contaminated specimen e.g vaginal discharge or infection or underlying renal disease

Significant in diagnosis of pre-eclampsia

Question 10

Haematuria

Answer 10

Blood - infection trauma tumour calculi

Contamination from vagina/haemorrhoids

Requires investigation

Question 11

Bright red/pink/dark red/green

Answer 11

Bleeding from bladder
Less fresh blood
Bleeding from kidneys
Pseudomonas infection

Question 12

Clarity

Answer 12

Becomes cloudy if left to stand due to precipitation of dissolves substances

Proteinuria may cause cloudy/foamy

Bacteriuria = cloudy/thick

Question 13

Odour

Answer 13

Stronger as concentration of urine increases

Urea breaks down into ammonium carbonate so stagnant urine smells of ammonia

Sweet odour = ketones

Fishy/offensive = infection

Question 14

Specific gravity

Answer 14

1.003 to 1.030

Reflects ability of kidneys to dilute or concentrate urine

Low levels = water diuresis
High level = dehydration

Question 15

Glycosuria

Answer 15

Appears in urine when blood glucose levels rise or if renal absorption lowers

May indicate gestational diabetes or diabetes, also normal physiological process in pregnancy due to glomerular filtration rate

Question 16

Ketonuria

Answer 16

Excessive breakdown of body fats

Due to fasting dehydration vomiting uncontrolled diabetes

Drugs may give false positive

Question 17

Urobilinogen

Answer 17

Normally present in small quantities

Larger amounts = liver abnormalities or excessive haemolysis

Question 18

Nitrites

Answer 18

Nitrates - normal component in diet - convert to nitrites in presence of bacteria in urinary system, e.g. e.coli

Indicate uti and mssu should be sent

False negatives if sample not in bladder for at least 4 hours

Question 19

Bilirubin

Answer 19

Due to hepatic or biliary disease

False positives due to drugs and false negs if sample stale or exposed to sunlight

Question 20

Procedure

Answer 20

Collection storage and handling must be sterile for accurate results
Check expiry date and latency of reagency strips
Obtain consent + discuss
Performed as soon after collection as poss
Reagent pads read at times specified on bottle
Compare blocks to corresponding colour chart
Lay strip flat in good lighting
Dispose correctly in line with trust policy
Remove gloves wash hands
Document findings
Discuss and refer