Pediatric Borreliosis is not Just Small Borreliosis: Similarities and Differences in Tick Borne Relapsing Fever in Children and Adults

Tick borne relapsing fever (TBRF) is a spirochete infection and is characterized mainly by recurring episodes of fever. Our objective was to characterize pediatric TBRF in comparison to adult TBRF. Data from the medical records of all patients diagnosed with TBRF in the 3 largest hospitals in Jerusalem, Israel, between the years 2004-2018 were collected and analyzed. During the study period, 92 patients were diagnosed with TBRF of whom 21 (22.8%) were children. Children had longer periods of fever compared to adults: 15.6 (±10.5) VS 7.9 (±9.9) days (p<0.01) and had 2.2 (±1.3) VS 0.6 (±0.8) relapses of fever at presentation. Children had a lower neutrophil count (4.8±2.7 *10⁹/liter VS 7±2.9 *10⁹/liter; P<0.01) and lower C- reactive protein levels (8.1±4.3 mg/dl VS 15.6±10.1 mg/dl; P<0.01). In conclusion, children exhibited a distinctly different course of TBRF, characterized by more episodes of fever and lower levels of inflammatory markers.