Myoglobin Urine

A myoglobin urine test is recommended to people who are suspected of having severe muscle damage as in the case of a trauma or an injury. Depending on the cause of muscle damage, symptoms vary but may include:

• Fever
• Abdominal pain
• Nausea and vomiting

Your healthcare provider may order a myoglobin urine test to confirm the diagnosis of rhabdomyolysis, a potentially life-threatening condition characterised by the breakdown of muscle tissue and release of its contents into the bloodstream, which may sometimes be associated with the use of cholesterol-lowering drugs called statins. The condition may lead to kidney damage and presents with the following signs:

• Serious muscle pain and fatigue
• Dark brown or reddish urine

This test also helps the healthcare provider to know whether the muscle injuries require treatment right away.

You do not need any special preparation for this test. Inform your healthcare provider of all the medicines, vitamins and supplements you may be taking - this includes any and all non-prescription or illegal drugs. Do not stop any medication unless instructed by your doctor.

The test is relatively safe and quick. You’ll be provided with a container from the laboratory to collect a sample of your urine. Your doctor or nurse may give you the following instructions for the procedure.

• If you are a man, clean the tip of the penis and women should clean the labia thoroughly before urinating
• Start urinating into the toilet first - allowing a few drops of urine to pass - and then into the container.  Catch about 30-50 mL of urine - until the marking on the container
• Finish urinating and hand over the container to the laboratory technician 

For infants, you will be provided with a urine collection bag along with a container. This will help collect the sample without spillage.

Wash the genital area of the infant thoroughly. Place the urine collection bag over his/her genital area and put the diaper on over the secured bag. Urine collection for infants is a little challenging, as the diaper may absorb the urine if the infant moves a lot. Check the diaper frequently and as soon as he/she has finished urinating in the bag, empty the contents into the collection container. Deliver the container to the laboratory once the required amount of sample is collected.

Normal results: 

Normally, a urine sample does not contain myoglobin. Some laboratories may report normal results as negative.

Abnormal results: 

The test results will show certain variations depending on the age, gender and method used for the test. Consult your doctor to understand what the test results precisely mean for you. 

Regardless, if myoglobin is detected in the urine, it is an indication of muscle damage. This muscle damage may be caused by:

• Certain infections and poisons
• Surgery 
• Coma or any situation in which you are unable to move
• Inherited conditions that cause muscle problems
• Unusually strenuous exercise
• Consumption of certain illegal drugs like heroin, cocaine, amphetamines
• Certain medicines such as statins and antipsychotics, especially when consumed in excess

Positive results may also be due to:

• Heart attack
• Malignant hyperthermia, a rare genetic disorder in which there is a sudden rise of body temperature and severe muscle contraction when anaesthesia is administered
• Muscular dystrophy (a disorder that causes muscle weakness and muscle tissue loss)
• Rhabdomyolysis
• Myositis (skeletal muscle inflammation) 
• Skeletal muscle ischaemia (reduced blood supply leading to oxygen deficiency) 
• Skeletal muscle trauma, e.g., following an accident

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.