Lyme disease testing by large commercial laboratories in the United States.

BACKGROUND: Laboratory testing is helpful when evaluating patients with suspected Lyme disease (LD). A 2-tiered antibody testing approach is recommended, but single-tier and nonvalidated tests are also used. We conducted a survey of large commercial laboratories in the United States to assess laboratory practices. We used these data to estimate the cost of testing and number of infections among patients from whom specimens were submitted. METHODS: Large commercial laboratories were asked to report the type and volume of testing conducted nationwide in 2008, as well as the percentage of positive tests for 4 LD-endemic states. The total direct cost of testing was calculated for each test type. These data and test-specific performance parameters available in published literature were used to estimate the number of infections among source patients. RESULTS: Seven participating laboratories performed approximately 3.4 million LD tests on approximately 2.4 million specimens nationwide at an estimated cost of $492 million. Two-tiered testing accounted for at least 62% of assays performed; alternative testing accounted for <3% of assays. The estimated frequency of infection among patients from whom specimens were submitted ranged from 10% to 18.5%. Applied to the total numbers of specimens, this yielded an estimated 240 000 to 444 000 infected source patients in 2008. DISCUSSION: LD testing is common and costly, with most testing in accordance with diagnostic recommendations. These results highlight the importance of considering clinical and exposure history when interpreting laboratory results for diagnostic and surveillance purposes.

Tick-borne diseases in Minnesota: an update.

Tick-borne diseases endemic to Minnesota include Lyme disease, babesiosis, anaplasmosis/ehrlichiosis, Powassan virus illness and Rocky Mountain spotted fever. Physicians need to be aware of these diseases and be vigilant about testing for them when patients present with acute febrile illness or rash within one month of potential tick exposure. In addition, they need to educate patients about these diseases and encourage prevention measures, especially use of tick repellents. This article reviews the epidemiology of these illnesses in Minnesota and the current recommendations for diagnosis and treatment.

First collection records of Aedes japonicus in Minnesota.

Aedes japonicus was first identified in the eastern United States during 1998 and has since spread to locations west of the Mississippi River. This species was found in Minnesota for the first time during 2007 at a tire recycling facility in Scott County and was identified during 2008 at 43 locations in 4 additional Minnesota counties south and east of the initial finding. These records document the presence of Ae. japonicus in 5 counties of southeastern Minnesota and indicate that the species overwinters locally.

Dispelling the chronic Lyme disease myth.

Lyme disease is a tick-borne illness endemic to Minnesota that can have potentially severe complications. As the incidence of Lyme disease continues to increase, it is important for physicians in Minnesota to become familiar with its clinical aspects, including the concept of "chronic Lyme disease." Chronic Lyme disease is a misnomer that is often applied to patients with nonspecific presentations who may or may not have a history of infection with Borrelia burgdorferi, the agent that causes Lyme disease. When a patient does present with persistent nonspecific symptoms attributed to chronic Lyme disease, clinicians should ascertain the presence of objective manifestations, obtain laboratory results, and get a history of tick exposure. If active infection with B. burgdorferi is unlikely, they should avoid prescribing empiric antibiotic therapy and instead thoroughly evaluate the patient for other possible causes of the complaints and recommend appropriate care.