Alex Matthews-King Health Correspondent
11 Feb 2019
Lyme Disease: Doctors Told Don’t Wait For Blood Tests Where Patients Have ‘Bullseye’ Rash
Doctors have been told to diagnose Lyme disease without waiting for blood test results if patients have the characteristic “bull’s eye” rash.
Blood tests for the tick-borne infections may miss the condition in the early weeks, according to new draft guidance published by the National Institute for Health and Care Excellence (Nice).
This could reduce the chances of a full recovery, the NHS treatment watchdog said. As a result, it said patients should be offered antibiotics where they show the characteristic ringed rash, known as erythema migrans.
The bull’s eye rash appears in around two thirds of cases usually within a month of a bite from an infected tick.
“For most people with Lyme disease, a course of antibiotics will be effective, so it is important we diagnose and treat people as soon as possible,” Professor Gillian Leng, director of health and social care at Nice, said. “A person with Lyme disease may present with a wide range of symptoms, so we have clear advice for professionals about the use of lab tests for diagnosis and the most appropriate antibiotic treatments.”
Tests can check for antibodies in the blood, however these may not appear until up to eight weeks after the patient is bitten.
It is hoped the new draft guidance will increase the number of early diagnoses and allow patients to receive treatment immediately, reducing the risk of further symptoms developing.
When there is no rash present and symptoms are unclear, doctors will be advised to carry out blood tests.
Professor Saul Faust, chairman of the guideline committee, said:
“Lab tests are necessary when a person’s symptoms are unclear, but they are not needed if a person presents the characteristic red rash, erythema migrans. Doctors should feel confident to prescribe antibiotics immediately for those with erythema migrans.”
Veronica Hughes, chief executive of Caudwell LymeCo, a UK charity for patients with Lyme disease, said:
“Waiting for blood test results always delays treatment. When a patient has the rash, this delay is unnecessary and reduces the likelihood of total cure.”
Additional reporting by Press Association
EM rash = Lyme. Period. The sad thing is many do not present with the classic EM rash, if they have a rash at all. The statement that two thirds present with the rash is objectionable. This article states the percentage varies from 27-80%, hardly a set number. https://www.lymedisease.org/lymepolicywonk-how-many-of-those-with-lyme-disease-have-the-rash-estimates-range-from-27-80-2/ (Table from this link)
Please notice that the CDC has much higher percentages. Why? They are using the surveillance definition for recording Lyme cases. This will naturally skew percentages towards rash reporting. It won’t include the thousands upon thousands that don’t notice or have the rash. Even the CDC with it’s stringent criteria report the percentages vary widely depending upon the state.
Also, rashes vary widely. Clinical diagnosis must consider any skin rash, regardless of its resemblance to the bull’s-eye.
“Researchers note that multiple textbooks and websites prominently feature the bull’s-eye image as a visual representation of Lyme disease.” They write, “This emphasis on target-like lesions may have inadvertently contributed to an underappreciation for atypical skin lesions caused by Lyme disease.” — Some Visible Signs of Lyme Disease Are Easily Missed or Mistaken, Science Daily, Apr 22, 2013 https://www.sciencedaily.com/releases/2013/04/130422132507.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Fhealth_medicine%2Flyme_disease+%28ScienceDaily%3A+Health+%26+Medicine+News+–+Lyme+Disease%29
Good news: you have a perfect EM rash you get treatment. Bad news: those with an atypical rash and those without a rash are hung out to dry.