TABLE 4

Univariate Analysis Comparing Lyme and Nonseptic Non-Lyme Arthritis

VariableLyme (N = 55)Nonseptic Non-Lyme (N = 78)P
Knee, n (%)47 (85)35 (45)<.001
Recent fever, n (%)25 (45)24 (31).08
Temperature ≥ 38.0°C, n (%)13 (24)17 (22).81
Tick-bite history, n (%)9 (16)3 (3).03
Peripheral WBC count, median (IQR), 103 cells per μL10.6 (9–11.8)10.2 (8.5–12.4).49
Peripheral ANC, median (IQR), 103 cells per μL6.7 (5.6–8.4)6.2 (4.5–8.3).20
ESR, median (IQR), mm/hr45 (28–57)27.5 (15.2–42.5)<.001
CRP, median (IQR), mg/dL2.7 (1.3–4.6)2.2 (0.2–5.9).24
Joint fluid
    WBC count, median (IQR), 103 cells per μL43.1 (23.9–62.4)15.1 (1.5–41.6)<.001
    Neutrophils, median (IQR), %86 (82–90)75 (44–88)<.001
    Lymphocytes, median (IQR), %2 (0–4)4 (1–20)<.001
    Monocytes, median (IQR), %9 (5–15)13 (4–25).17