Lyme disease can create confusion for clinicians, especially when patients think it is causing their chronic, nonspecific symptoms, said Dr. Eugene Shapiro.
Patients with genuine Lyme disease may indeed have nonspecific symptoms, but – given that the disease does not cause chronic, nonspecific symptoms in the absence of objective signs of the illness – patients must also have an objective sign of Lyme disease, he explained.
Lyme disease can be classified into the following three categories:
• Early localized disease. This is "simply erythema migrans," said Dr. Shapiro, professor of pediatrics and of epidemiology and public health at Yale University, New Haven, Conn. It starts at the site of the tick bite, and expands for a few weeks if left untreated. Many people associate Lyme disease with a bull’s-eye, but it is more common to see uniform erythema, he said. "Don’t think that it is not erythema migrans just because there is no target lesion." Also, it is typical for the area of erythema not to be perfectly round, he added.
• Early disseminated disease. Signs of Lyme disease at this stage include multiple erythema migrans, symptoms of a flulike illness, aseptic meningitis, neuritis, and carditis. Meningitis is relatively uncommon in cases of Lyme disease, but it does occur, Dr. Shapiro noted. Neuritis (seventh-nerve palsy) is more common, but it is unaffected by treatment and usually resolves, he said.
• Late Lyme disease. Late disease is characterized by arthritis, and more than 90% of those cases of arthritis involve the knee, Dr. Shapiro said. The arthritis may be monoarticular or pauciarticular, and the duration of the arthritis varies, but it usually resolves with treatment, he said.
The question of "chronic" Lyme disease poses a different conundrum for clinicians. Although medically unexplained symptoms are common in these patients, most who complain of "chronic" Lyme disease have no evidence of ever having had the disease, based on history or serologic tests, he said. "We doctors are very good at treating diseases, but we are very poor at managing symptoms without a diagnosis," he added. His advice for managing such patients is to focus on treating the symptoms with a combination of counseling, increased exercise, improved sleep, cognitive-behavioral therapy, and in some cases, medication.
"Associated pathology is rare and rarely missed, whereas psychiatric diagnoses are common and often missed" in these patients, he said.
When it comes to prevention, be selective in ordering serologic tests, Dr. Shapiro emphasized. "Positive serologic test results without objective signs are very likely false-positive results," he said.
Dr. Shapiro made his remarks in Cambridge, Mass., at a conference on pediatric infectious diseases that was sponsored by Boston University, Pediatric News, and Family Practice News. Pediatric News and Family Practice News are owned by Elsevier. He disclosed that he is the official media spokesperson on Lyme disease for the Infectious Diseases Society of America.