Electrocardiographic findings in children with erythema migrans

To assess electrocardiographic findings in children with erythema migrans and to compare them with findings obtained in a healthy control group of comparable age and with a similar proportion of boys and girls.

Electrocardiograms were carried out in 147 children under the age of 15 years before treatment with antibiotics for erythema migrans (solitary 68 patients, multiple 79 patients) and in the control group of 148 healthy children.

Abnormal electrocardiographic findings were detected more often in healthy children than in patients (14% versus 5%; P = 0.0303) and among patients more often in boys than in girls (10% versus 0%; P = 0.0107). Electrocardiographic abnormalities characteristic for Lyme borreliosis, such as atrioventricular blocks, were rare: in patients with erythema migrans only one child had first-degree atrioventricular block; in the control group one child had first-degree and another had second-degree atrioventricular block. Patients with erythema migrans had shorter PR and RR intervals and lower R and S wave voltages in V1 than the healthy children. Comparison among patients with solitary and multiple erythema migrans did not reveal significant electrocardiographic differences. The frequency of electrocardiographic abnormalities in patients with erythema migrans was not associated with the presence of systemic symptoms, or with the presence of meningitis or the isolation of Borrelia burgdorferi sensu lato from the blood.

Electrocardiographic abnormalities in children with erythema migrans are mild, nonspecific and rare. The presence of clinical signs and symptoms indicative or suggestive of disseminated Lyme borreliosis is not associated with higher frequency of such abnormalities. Comparison of findings in patients with erythema migrans and healthy children revealed several distinctions, some of which might have been interpreted as a result of altered activity of the autonomic nervous system.