The fact that the “umbrella diagnosis” of ME/CFS shares its symptoms with many illnesses will complicate diagnosis and research until a specific biomarker is found. One “overlapping” diagnosis is Lyme disease (caused by Borrelia bacteria transmitted via tick-bites); indeed, there have been suggestions for many years that a subgroup of people with ME/CFS do, in fact, have undiagnosed Lyme disease, particularly those who live in areas of the world where tick-bites are common.
The Tropical and Infectious Disease Unit in Liverpool has published the results of a case note review of patients referred with suspected Lyme disease, and it makes fascinating reading. In the five years from 2006 to 2010, 115 patients had been referred. The commonest reasons for referral were fatigue (in 44% of patients), rash (32%), and neurological (19%) and rheumatological (17%) symptoms. After investigation at the Unit, 27 patients (23%) were diagnosed with Lyme disease. However, 38 patients (33%) were given a diagnosis of ME/CFS, since none of them had clinical features that were suggestive of active Lyme disease, or a positive reference laboratory serology. The remaining patients were diagnosed with other medical conditions, or obtained no specific diagnosis. Intriguingly, almost half of people with ME/CFS had been labelled as having “chronic Lyme disease” by alternative practitioners and had been advised to take multiple and prolonged courses of antimicrobials. Overall, at least 53 unnecessary antibiotic courses had been given by non-NHS practitioners (and 21 given by NHS practitioners) to people who did not have Lyme disease.
Similar high levels of over-diagnosis of Lyme disease by non-specialists have been reported by other referral centres in the UK and North America, particularly to ME/CFS or fibromyalgia patients whose “disputed” illness is always susceptible to misdiagnosis. As the authors say, “the frustration expressed by these patients is compounded by the substantial costs of repeated attendances… of unvalidated investigations (often sent overseas) and of multiple lengthy courses of anti-microbial agents, with potential for toxicity”.
Reference: Lyme disease in a British referral clinic. Cottle et al. QJM 2012 Jun; 105(6): 537-43.