Mid-stream urine (MSU) microscopy & culture (uti cystitis)
Microbiology
Notes
The information given here is intended for use by healthcare professionals. Please see Lab Tests Online-UK for more general advice, links and background.
A minimum of 2 ml of urine is required for routine analysis. Exceptions may be made for babies and renal patients. In other patients small samples will not be processed.
All samples are screened for pyuria and bacteruria using an automated image analysis system, and then cultured.
Urgent microscopy requests may be requested on children according to current NICE guidelines.
- Investigations for casts, cysteinuria and fastidious organisms are not performed routinely and must be specially requested. Prostatic massage samples can be processed on special request.
- Antibiotic guidelines for the treatment of UTI (accessible to Trust users only)
- See also:
Sample requirements
30mL urine bottle with preservative
Bottles should be filled to the red line
30mL sterile universals without preservative are accepted
Collection of Mid-Stream Sample of Urine
Required information
- Relevant clinical details
- Current or recent antibiotic therapy
- Antibiotic allergies
- Pregnancy status
- Suspected prostatitis or epididymo-orchitis
Storage/transport
Samples in 30 mL urine bottles with preservative may be stored at room temperature for up to 24 hours. If transport is delayed beyond that samples should be refrigerated.
Samples in plain sterile universals must be transported without delay. Refrigerate samples if transport is delayed.
Turnaround time
Negative: 1 - 3 days
Positive: 2 - 4 days
Multi-resistant organisms require additional sensitivity testing and can take longer to process.