529 - Refractory Lyme arthritis in children presenting to the emergency department

Publication Number: 2514.529

Hannah G. Fine, Wesleyan University, Waban, MA, United States; Christopher Woll, Albany Medical Center, Albany, NY, United States; Pui Lee, Boston Children's Hospital, Boston, MA, United States; Peter A. Nigrovic, Boston Children's Hospital, Boston, MA, United States; Lise Nigrovic, Boston Children's Hospital, Boston, MA, United States

Background: Most children with Lyme arthritis recover with antibiotics alone, although approximately one in five referred to a rheumatology clinic developed refractory arthritis.

Objective: Our aim was to determine how frequently children who present to the emergency department (ED) with acute Lyme arthritis develop refractory arthritis.

Design/Methods: We enrolled children who presented to a single ED with acute arthritis and selected those with Lyme arthritis defined with a positive two-tier Lyme disease serology obtained within 30 days of enrollment. Follow-up included a 1-month phone call and 1-year medical record review. We defined refractory Lyme arthritis with receipt of either intra-articular steroids or an immunomodulatory medication within 12 months of enrollment.

Results: Of the 124 children with Lyme arthritis, the median age was 8 years [interquartile range (IQR) 5-11 years] and 81 (65%) were male. The majority had a monoarthritis (n=123; 99%) of which the knee was the most frequently involved joint (n=96; 77%). Over the year after enrollment, 64 children (52%) had Lyme disease specific follow-up, 48 (39%) had unrelated follow-up without documented arthritis and 12 (9%) did not have recorded follow-up. The median duration of antibiotics was 28 days [IQR 21-28 days]; 16 children (13%) received > 4 weeks of antibiotics. Overall, 6 children (5%) had refractory arthritis (Figure): 6 received an immunomodulator medication and 3 also received an intra-articular steroid injection.

Conclusion(s): Most children with Lyme arthritis who present to the ED recover with antibiotics alone. Only a small minority required immunomodulatory medications or intra-articular steroids within one year.

Figure:
PAS abstract Figure 11_01_25.pdfStudy patients