How to collect a MSU

An MSU is a urine sample that is sent to the hospital lab to test for bacteria which can cause a ​urine infection.

What is an MSU

A midstream sample means you do not collect the first or the last part of urine, the sample is collected from the middle part of the urine stream. 

You will need to ask your GP practice for a special urine container and a form. Label the urine container with your name, date of birth, the date and time of the sample. Some surgeries will attach a pre-printed label to the urine pot with your details on. 

Most urine infections do not require an MSU to be done. This is because they are diagnosed on the basis of your symptoms. However, there are some situations where an MSU is recommended which include: 

  • to confirm a urine infection in cases where symptoms that are not typical of one.
  • to decide which is the best antibiotic to use, particularly if you have had recent treatment with an antibiotic that has not cleared the urine infection fully. 

How to take an MSU

  1. Wash your hands with soap and water.
  2. Wash your genital area if possible to help remove any bacteria from the skin.
  3. For women, hold open the entrance to the vagina. For men, retract the foreskin if possible. Avoid touching any part of the urine container with your genitals to reduce contamination. 
  4. Start to urinate in the toilet, after a couple of seconds, place the urine pot or a clean container (that has been washed thoroughly with detergent and hot water) to collect some urine.
  5. Ensure you screw the lid of the urine pot shut (if you collected the urine in another container then pour this carefully into the urine sample container). 
  6. Wash and dry your hands.
  7. Try to drop this container at your GP surgery within an hour, following any instructions given to you by your GP practice. If it is not possible to drop it off within the hour, then read the instructions below on how to store the urine. 

How do I store a sample

You can store the urine sample in a fridge for up to 24 hours. Please ensure that it is not leaking and place it in a sealed plastic bag. 

If a urine sample is not stored correctly then the bacteria can multiply and this can affect the accuracy of the test results. 

How do I get my results

Contact your GP surgery for the results, following any instructions your surgery may have given you on how to do this. The results are usually back within 2-4 days. Your practice can advise you if any further treatment is required. 

Article written by
Disclaimer: This article is solely for information purposes. It is not to replace a consultation with a qualified health professional. It should not be used for the diagnosis or treatment of medical conditions. The article is based on the opinions of the author who retains copyright. You are advised to make your own health decisions based on your research and alongside a qualified health professional. Please consult a doctor if you have any health concerns.

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