TABLE 2

Patient Characteristics by Arthritis Type

CharacteristicsSeptic ArthritisLyme ArthritisOther Arthritis
(N = 26)(N = 32)(N = 180)
Demographics
 Age, y, median (IQR)7.5 (5.6–10.7)7.9 (4.0–11.3)5.6 (4.0–10.7)a
 Male sex, n/N (%)12/26 (46)14/32 (44)106/180 (59)
 Race, n/N (%)
  White22/24 (92)22/29 (76)122/163 (75)
  African American0/24 (0)2/29 (7)4/163 (2)
  Other2/24 (8)5/29 (17)34/163 (21)
 Hispanic ethnicity, n/N (%)1/23 (4)2/22 (9)25/148 (17)
 Presentation during peak Lyme season, n/N (%)16/26 (62)15/32 (47)74/180 (41)
Clinical history, n/N (%)
 Presence of fever22/26 (85)a9/32 (28)69/180 (38)
 Antibiotic pretreatment4/26 (15)1/32 (3)18/180 (10)
 Inability to bear wt25/26 (96)24/26 (92)135/170 (79)
Laboratory studies
 Peripheral WBC count (cells per μL × 103),a median (IQR)10.8 (8.5–12.8)10.5 (9.3–13.2)11.0 (8.8–14.6)
 Peripheral ANC count (cells per μL × 103),a median (IQR)7.8 (5.4–9.5)6.8 (5.9–9.0)7.2 (5.0–10.0)
 ESR, mm/h, median (IQR)59 (40–84)a36 (25–55)27 (14–47)
 CRP, mg/dL, median (IQR)10.4 (7.2–17.1)a2.0 (1.2–5.0)1.8 (0.3–4.6)
 Synovial fluid WBC count, cells per µL, median (IQR)126 130a (8300–209 332)53 954a (33 789–73 375)20 267a (2500–64 012)
 Synovial fluid ANC, cells per μL, median (IQR)123 000 (78 392–190 440)50 290 (36 333–62 040)15 362 (1645–54 196)
 Positive blood culture result, n/N (%)8/22 (36)a0/32 (0)4/180 (2)
 Positive Gram-stain synovial fluid result, n/N (%)17/26 (65)a0/32 (0)0/180 (0)
 Positive synovial fluid culture result, n/N (%)25/26 (96)a0/32 (0)0/180 (0)
Radiology studies performed, n/N (%)
 Radiograph24/26 (92)30/32 (94)155/180 (86)
 Ultrasound21/26 (81)29/32 (91)166/180 (92)
 MRI12/26 (46)7/32 (22)49/180 (27)
Clinical management
 Arthroscopic joint irrigation26 (100)a13 (41)55 (31)
 Hospitalized26 (100)a26 (81)113 (63)
  • a Statistical difference using pairwise comparisons (P < .05).