mlw sop micro 016 urine

8/12/2019 Mlw Sop Micro 016 Urine

1/10


2/10

MLW.SOP.L.MICRO.016 Version 1 Page 2 of 10

Contents

1. BACKGROUND .................................................................................. 32. PURPOSE ........................................................................................... 43. RESPONSIBILITIES ........................................................................... 44. PROCEDURE ..................................................................................... 4

4.1 MATERIALS NEEDED ................................................................... 44.2 STORAGE CONDITIONS .............................................................. 44.3 TEST PROCEDURE ...................................................................... 44.4 QUALITY CONTROL ...................................................................... 54.5 INTERPRETATION OF RESULTS ................................................. 54.6 LIMITATIONS ................................................................................. 6

5. HEALTH & SAFETY ........................................................................... 66. ASSOCIATED PROCEDURES .......................................................... 67. REFERENCES .................................................................................... 78. APPENDICES ..................................................................................... 8Appendix 1: Fastread 102 counting chamber instructions for use.... 8

9. Training Record for this SOP ......................................................... 10


3/10


1. BACKGROUND

Urinary tract infection (UTI) results from the presence and multiplication of

microorganisms in one or more structures of the urinary tract with associated tissue

invasion. This can give rise to a wide variety of clinical syndromes. These include

acute and chronic pyelonephritis (kidney and renal pelvis), cystitis (bladder),

urethritis (urethra), epididymitis (epididymis) and prostatitis (prostate gland). Infection

may spread to surrounding tissues (e.g. perinephric abscess) or to the bloodstream.

Protection against infection is normally given by the constant flow of urine and

regular bladder emptying. Urine is a poor culture medium for many bacteria due to

its acidity, high urea concentration and variable osmolality and, in men, possibly

partly as a result of antibacterial activity of prostatic secretions1.

Bacteriuria Implies that bacteria are present and may be cultured from urine. The

patient may or may not be symptomatic.

Symptomatic patients They may be bacteriuric or abacteriuric. Symptoms in

children and the elderly, when present, may be non-specific and difficult to interpret.

Frequency The average bladder capacity is about 500 mL. Significant reduction

in capacity accompanies acute inflammation which can lead to an increase in thefrequency of micturition.

DysuriaPainful and difficult micturition.

UrgencyA strong desire to empty the bladder, which can lead to incontinence.

NocturiaWaking in the night one or more times to void the bladder2.

Nocturnal enuresis The involuntary voiding of urine during sleep, i.e. bed-wetting.

Incontinence The involuntary leakage of urine. The commonest form of this is

stress incontinence where leakage accompanies an increase in intra-abdominal

pressure due to sneezing, coughing or laughing. Overflow or dribbling incontinence

accompanies an overfilled bladder.

Prostatism Symptoms include: hesitancy or delay in initiating micturition,

intermittency or interruption, and reduced force of the urine stream resulting from

prostate gland pathology.

Renal colic This is characterised by very severe cramping pain resulting from

distension of the ureter and pelvis above an obstruction such as a renal stone.

Often accompanied by frequency and urgency.


4/10


Asymptomatic bacteriuria Common in several patient groups, particularly the

elderly, pregnant women and diabetic patients.

2. PURPOSE

This SOP explains how to perform Urine microscopy and culture on mid-stream

urine samples received at the MLW laboratory. If any other type of urine specimen

is received this should only be processed after discussion with, and advice

from, the clinical microbiologist.

3. RESPONSIBILITIES

1) Laboratory technicians

2) Visiting clinical scientists

4. PROCEDURE4.1 MATERIALS NEEDED

1) Fastread 102 counting chamber

2) Blood agar plate

3) CLED agar plate

4) Disposable 1lsterile loop

5) Pipette

4.2 STORAGE CONDITIONS

1) Agar plates should be stored at 2-8oC and used within 1 month of their

production.

2) All other materials are stored at room temperature

4.3 TEST PROCEDURE

Day one:

1) Gently mix the urine sample by inverting the tube several times (do not

shake the sample)


5/10


2) Perform a cell count using a Fastread 102 counting chamber (see

appendix 1)

3) Place 1 drop of urine using a pipette into the sample application area of

the chosen counting well and allow it to distribute evenly throughout the

counting area.

4) Count the numbers of cells (white cells and red cells) across all ten large

grids (4x4 small grids) to achieve a count per l or count a smaller area

and do the appropriate calculation to achieve a count per l.

5) To achieve a count per ml multiply the count per l by 1000.

6) Inoculate 1l of urine sample onto a blood agar plate and a CLED agar

plate using a 1l sterile loop and spread to achieve single colony growth

7) Incubate both plates in air at 37oC overnight

Day two:

1) Check both plates for bacterial growth and identify the organisms

according to interpretation of results (4.5) below.

2) Perform sensitivity tests on significant bacterial growth (as defined by the

table in interpretation of results below) using MLW.SOP.MICRO.208.

Day three:

1) Read and interpret sensitivity tests as describe in MLW.SOP.MICRO.208

4.4 QUALITY CONTROL

See associated procedures

4.5 INTERPRETATION OF RESULTS

Identification of bacterial growth and subsequent sensitivity testing should only be

done if the bacterial growth is considered significant in conjunction with the

microscopic analysis (see table below).

White cell count Culture result (per agar plate) Significant

Any Pure single organism 10 colonies Yes


6/10


Any Pure single organism


7/10


7. REFERENCES

1. Sobel JD. Pathogenesis of urinary tract infections. Host defenses. Infect Dis

Clin North Am 1987;1:751-72.

2. Van Kerrebroeck P, Abrams P, Chaikin D, Donovan J, Fonda D, Jackson S,

et al. Nocturia. Neurourology Urodynamics 2002;21:179-83.


8/10


8. APPENDICES

Appendix 1: Fastread 102counting chamber instructions for use


9/10



10/10


9. TRAINING RECORD FOR THIS SOP

The following have been trained in this SOP and have demonstrated adequate

knowledge of its contents:

Name of Trainee Name of Trainer Signature/Date of

Trainee

Signature/Date of

Trainer*

mlw sop micro 016 urine

Documents