With the spring and summer coming there will be more people going outdoors where they may brush against vegetation and catch Lyme disease from a tick. The ticks will be on the hunt for animal blood, especially after this wet winter. Lyme disease is seen throughout the UK and is more prevalent than many people realise.1 A study of GP data showed that Lyme disease is diagnosed in every region in the country. Birds can carry infected ticks, so infected ticks can be found everywhere.
For patients presenting with the erythema migrans rash, the National Institute for Health and Care Excellence (NICE) recommends diagnosis and treatment of Lyme disease without laboratory testing.2 However, more than half of all cases do not have this distinctive rash and so they need to be diagnosed using other criteria. Along with many cases not having the rash is the added difficulty that laboratory testing for Lyme disease has inherent limitations, and false negative results can occur. If the test is done too early the person may not have developed antibodies to the bacteria that causes Lyme disease.
NICE has written that, if Lyme disease is still suspected in people with a negative result who were tested within 4 weeks from symptom onset, then the test should be repeated 4–6 weeks after the first test. Lyme disease can lead to a wide range of symptoms, so diagnosis can be difficult.
Oral antibiotic treatment may be appropriate in the early stages even if there is some uncertainty about the diagnosis because avoiding a delay in treatment is important to prevent long-term morbidity. NICE recommends considering starting treatment with antibiotics while waiting for the test results if there is a high clinical suspicion of Lyme disease.
- © British Journal of General Practice 2021