Emergency department presentations of Lyme disease in children

Objective: To review the clinical characteristics and diagnostic evaluation of children with Lyme disease evaluated in an emergency department (ED) in an endemic area. Design: A retrospective review of the demographic, historical, clinical, and laboratory data of pediatric patients with a final diagnosis of Lyme disease. Setting: The pediatric ED of an urban university hospital. Participants: Children with Lyme disease evaluated during the three‐year period from 1992 to 1994. Results: Twenty‐nine children ranging in age from three to 19 years who were diagnosed with Lyme disease subsequent to a visit to a pediatric ED were identified. Four patients had early localized disease with erythema migrans and varying degrees of systemic symptoms. Ten had early disseminated Lyme disease, with multiple erythema migrans, neurologic involvement (including three patients with pseudotumor cerebri), or carditis. Fifteen cases of late Lyme disease with arthritis were identified. Recognition of Lyme arthritis proved particularly difficult; seven children were initially diagnosed as having septic arthritis, six of whom underwent arthrotomy. Marked elevations of the erythrocyte sedimentation rate and synovial fluid white blood cell counts were observed in these patients, making it difficult to distinguish Lyme disease from septic arthritis on the basis of laboratory findings. Conclusion: Lyme disease is an infrequent, often difficult, diagnosis in children who present to an ED. Early disseminated and late disease predominate; classic erythema migrans is uncommon in the ED in comparison with other ambulatory venues. Diagnosis of Lyme arthritis may be difficult; exposure in an endemic area and clinical findings may help distinguish it from septic arthritis. Overall, underdiagnosis of Lyme disease may actually be more of a problem than overdiagnosis in the ED setting. Recognition of Lyme disease by emergency medicine practitioners requires familiarity with its epidemiology and its multiple manifestations.