TABLE 1

Demographic and Clinical Features of 179 Patients With Acute Monoarticular Arthritis

VariableLyme (N = 55)Septic (N = 46)Nonseptic Non-Lyme (N = 78)P
Age, median (IQR), y8.1 (4.9–10.7)8 (3–11)6.2 (4.4–11).71
Male gender, n (%)31 (56)31 (67)46 (59).50
Duration of symptoms, median (IQR), d2 (1–4)4 (2–7)2 (1–6).26
Presentation during Lyme season, n (%)a27 (49)23 (50)39 (50).99
History, n (%)
    Recent fever25 (45)38 (83)24 (31)<.001
    Recent trauma11 (20)16 (35)20 (26).24
    Recent illness11 (20)17 (37)22 (28).16
    History of tick bite9 (16)1 (2)3 (3)<.01
    Joint pain54 (98)45 (98)77 (99).93
Physical examination, n (%)
    Erythema over joint10 (18)12 (26)11 (14).25
    Joint warmth33 (60)15 (33)21 (27)<.001
    Range of motion: limited33 (60)22 (48)42 (54).47
    Range of motion: non–weight bearing21 (38)24 (52)32 (41).34
    Temperature ≥ 38.0°C at triage13 (24)22 (48)17 (22)<.01
    Knee47 (85)10 (22)35 (45)<.001
    Hip7 (13)20 (43)38 (49)<.001
    Other joint1 (2)16 (35)5 (6)<.001
Hospital admission39 (71)45 (98)37 (47)<.001
Surgical irrigation, n (%)22 (40)44 (96)16 (21)<.001
  • a Peak Lyme season: June through October.