From the Research
For a patient with a history of Lyme disease 10 years ago who still experiences fatigue, I recommend starting with a comprehensive metabolic panel, complete blood count, thyroid function tests, vitamin D level, vitamin B12 level, and ferritin, as these tests can help identify common causes of persistent fatigue. These basic tests can identify common causes of persistent fatigue such as anemia, thyroid dysfunction, or nutritional deficiencies. Additionally, consider testing for other tick-borne co-infections that might have been present with the original Lyme infection, including Babesia, Bartonella, and Anaplasma/Ehrlichia, as suggested by 1. An inflammatory marker panel including C-reactive protein and erythrocyte sedimentation rate may help assess ongoing inflammation. While Lyme antibody tests (ELISA and Western Blot) could be performed, they often remain positive after treatment and may not indicate active infection, as noted in 2. Post-treatment Lyme disease syndrome (PTLDS) is a recognized condition where symptoms persist despite appropriate antibiotic therapy, with no evidence of ongoing infection, as discussed in 3. The fatigue could also be unrelated to the previous Lyme infection, so consider screening for other conditions like sleep apnea, depression, chronic fatigue syndrome, or fibromyalgia based on the patient's other symptoms and clinical presentation. It is also important to note that severe fatigue is rarely a long-term complication of Lyme disease, as found in a study published in 4, which followed patients with culture-confirmed Lyme disease for 11 to 20 years after presentation. Therefore, a thorough evaluation of the patient's overall health and potential underlying conditions is necessary to determine the cause of their fatigue.