Explain Post-lyme disease syndrome 

Some treated patients whose objective manifestations of Lyme disease have resolved with antibiotic treatment report subjective symptoms such as fatigue, musculoskeletal pain or cognitive difficulties of varying intensity that may persist over prolonged periods. Microbiologic evaluation of these patients has failed to find evi- dence of either persistent B. burgdorferi infection or of co-infection with another tick-borne pathogen. Two controlled studies, one in 78 patients seropositive for IgG antibodies to B. burgdorferi and another in 51 seroneg- ative patients, both with a history of treated Lyme disease and persistent symptoms for at least 6 months, compared 1 month of IV ceftriaxone plus 2 additional months of oral doxycycline with placebo and found no clinical benefit of antibiotic therapy.