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You are here: / Home / Knowledge / Guidance / Legionnaires’ Disease Testing – The Importance of Early Diagnosis

Legionnaires’ Disease Testing & the Importance of Early Diagnosis

Legionnaires' disease testingThe importance of Legionnaires’ disease testing to aid early diagnosis cannot be stressed too highly, especially when a patient presents with symptoms that may suggest they have contracted this potentially life-threatening disease.  The disease can present similarly to a severe cold or flu in its early stages. Some patients may be diagnosed with pneumonia, as the bacteria can then progress into the lungs. Anyone who develops such symptoms should see their doctor as a matter of urgency, regardless of whether they are eventually diagnosed with Legionnaires’ disease or not. It is highly likely that treatment will be required to combat the infection.

    • Learn more about Legionnaires’ disease

Legionnaires’ disease testing and diagnosis – how are patients tested?

If someone has symptoms of Legionnaires’ disease, they should make their recent travel history known to their GP. This can help identify whether the disease might be present and where it may have been contracted, although this may not always be relevant. Remember, outbreaks do occur within the UK and also abroad.

A urine test can be performed to look for the presence of legionella bacteria in the patient’s body. This is known as a urinary antigen test. Secretions from the lower respiratory system can also be tested for the presence of the bacteria using laboratory based culture techniques. The sooner this can be done, the better – and ideally it should be performed prior to the start of any course of antibiotics designed to combat the condition. However, since beginning the antibiotics as soon as possible is of paramount importance, this should always take priority.

    • More on diagnostic tests for Legionnaires’

What are the main indications that legionella testing should be undertaken?

Not all situations where someone presents with flu-like symptoms or pneumonia-like symptoms will require Legionnaires’ testing to be performed. To work out whether this should be done, several indicators will be looked at. If these raise one or more red flags, the patient will be tested as per the above methods to see whether the legionella bacteria are present in their system.

For example, a recent travel history, as mentioned above, could provide a clue to the nature of the illness. If someone has previously been treated with antibiotics for pneumonia as an outpatient and there has been no progress, this may indicate it could be Legionnaires’ disease instead.

Anyone with suspected pneumonia who is in hospital, or whose immune system is somehow compromised, should also be tested in the above way.

Of course, there could be other evidence the patient has been in a situation where Legionnaires’ disease has already been diagnosed and confirmed in others. If this is the case, testing would be of paramount importance here, too. This applies to anyone at risk of developing the disease, perhaps because of the setting they were in prior to their illness developing. Such testing for Legionnaires’ disease can help to provide a definitive answer to the nature of their illness.

    • More about testing for Legionella bacteria in water

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