In untreated Lyme disease, signs and symptoms of early dissemination may manifest within weeks to months of a tick bite, Dr. John M. Costello and co-investigators note. To characterize the clinical course of Lyme carditis in children, they reviewed cases of 207 children treated between 1994 and 2008 for early disseminated Lyme disease.
Records showed that 33 (16%) had carditis, along with a wide range of systemic involvement. According to the Boston-based research team, only one patient presented with isolated carditis and no erythema migrans or noncardiac systemic manifestations. Duration of hospitalization ranged from 1 to 13 days, and there were no deaths.
Fourteen patients had advanced heart block, including 9 with complete block, but recovery of sinus rhythm took no more than 7 days.
In addition, among the 33 patients with carditis, 4 had depressed ventricular systolic function and 3 of them required mechanical ventilation, temporary pacing, and inotropic support.
Analysis showed that significant independent predictors of Lyme carditis were age over 10 years (adjusted odds ratio 8.3), arthralgias (OR 5.8), and cardiopulmonary symptoms (OR 76.8). Sensitivity and specificity of cardiopulmonary symptoms for Lyme carditis were 42% and 99%, respectively.
Of 27 patients for whom follow-up data were available, complete recovery occurred in 24. One patient had ongoing second-degree atriventricular block at 2.7 years. The other 2 patients had improved but still had mildly prolonged PR intervals at short-term follow-up.
Thus, Dr. Costello’s group states, “A full recovery should be expected with supportive care and antibiotic therapy.” However, they point out that 6 patients had prolonged corrected QT intervals and advise physicians “to avoid drugs that prolong the QT interval in these patients until the electrocardiogram has normalized.”
Pediatrics 2009;123:e835-e841.
