New clinical practice guidelines on Lyme disease place a strong emphasis on antibody testing to assess for rheumatologic and neurologic syndromes. “Diagnostically, we recommend testing via antibodies, and an index of antibodies in cerebrospinal fluid [CSF] versus serum. Importantly, we recommend against using polymerase chain reaction [PCR] in CSF,” Jeffrey A. Rumbaugh, MD, PhD, a coauthor of the guidelines and a member of the American Academy of Neurology, said in an interview.
The Infectious Diseases Society of America, AAN, and the American College of Rheumatology convened a multidisciplinary panel to develop the 43 recommendations, seeking input from 12 additional medical specialties, and patients. The panel conducted a systematic review of available evidence on preventing, diagnosing, and treating Lyme disease, using the Grading of Recommendations Assessment, Development and Evaluation model to evaluate clinical evidence and strength of recommendations. The guidelines were simultaneous published in Clinical Infectious Diseases, Neurology, Arthritis & Rheumatology, and Arthritis Care & Research.
This is the first time these organizations have collaborated on joint Lyme disease guidelines, which focus mainly on neurologic, cardiac, and rheumatologic manifestations.
“We are very excited to provide these updated guidelines to assist clinicians working in numerous medical specialties around the country, and even the world, as they care for patients suffering from Lyme disease,” Dr. Rumbaugh said.
When to use and not to use PCR
Guideline authors called for specific testing regimens depending on presentation of symptoms. Generally, they advised that individuals with a skin rash suggestive of early disease seek a clinical diagnosis instead of laboratory testing.
Recommendations on Lyme arthritis support previous IDSA guidelines published in 2006, Linda K. Bockenstedt, MD, professor of medicine at Yale University, New Haven, Conn., and a coauthor of the guidelines, said in an interview.
To evaluate for potential Lyme arthritis, clinicians should choose serum antibody testing over PCR or culture of blood or synovial fluid/tissue. However, if a doctor is assessing a seropositive patient for Lyme arthritis diagnosis but needs more information for treatment decisions, the authors recommended PCR applied to synovial fluid or tissue over Borrelia culture.
“Synovial fluid can be analyzed by PCR, but sensitivity is generally lower than serology,” Dr. Bockenstedt explained. Additionally, culture of joint fluid or synovial tissue for Lyme spirochetes has 0% sensitivity in multiple studies. “For these reasons, we recommend serum antibody testing over PCR of joint fluid or other methods for an initial diagnosis.”
Serum antibody testing over PCR or culture is also recommended for identifying Lyme neuroborreliosis in the peripheral nervous system (PNS) or CNS.
Despite the recent popularity of Lyme PCR testing in hospitals and labs, “with Lyme at least, antibodies are better in the CSF,” Dr. Rumbaugh said. Studies have shown that “most patients with even early neurologic Lyme disease are seropositive by conventional antibody testing at time of initial clinical presentation, and that intrathecal antibody production, as demonstrated by an elevated CSF:serum index, is highly specific for CNS involvement.”
If done correctly, antibody testing is both sensitive and specific for neurologic Lyme disease. “On the other hand, sensitivity of Lyme PCR performed on CSF has been only in the 5%-17% range in studies. Incidentally, Lyme PCR on blood is also not sensitive and therefore not recommended,” Dr. Rumbaugh said.
Guideline authors recommended testing in patients with the following conditions: acute neurologic disorders such as meningitis, painful radiculoneuritis, mononeuropathy multiplex; evidence of spinal cord or brain inflammation; and acute myocarditis/pericarditis of unknown cause in an appropriate epidemiologic setting.
They did not recommend testing in patients with typical amyotrophic lateral sclerosis; relapsing remitting multiple sclerosis; Parkinson’s disease, dementia, or cognitive decline; new-onset seizures; other neurologic syndromes or those lacking clinical or epidemiologic history that would support a diagnosis of Lyme disease; and patients with chronic cardiomyopathy of unknown cause.
The authors also called for judicious use of electrocardiogram to screen for Lyme carditis, recommending it only in patients signs or symptoms of this condition. However, patients at risk for or showing signs of severe cardiac complications of Lyme disease should be hospitalized and monitored via ECG.