Table 4.
Risk factors for severe infection in patients with babesiosis
| (N = 128) | Severe infection | |||
|---|---|---|---|---|
| Univariate analyses | ||||
| Yes (26) | No (102) | RR (95% CI) | P value | |
| Age > 75 years | 7 | 23 | 1.67 (0.54–2.50) | 0.69 |
| Male | 18 | 67 | 0.88 (0.42–1.86) | 0.73 |
| Comorbidities | 22 | 77 | 0.62 (0.23–1.66) | 0.32 |
| Cardiac | 11 | 40 | 1.11 (0.55–2.21) | 0.77 |
| Asplenia | 7 | 7 | 3.00 (1.54–5.84) | < 0.01 |
| Autoimmune | 5 | 6 | 2.53 (1.19–5.38) | 0.04 |
| Any Coinfection | 10 | 37 | 1.08 (0.53–2.18) | 0.84 |
| Signs and symptoms | ||||
| Fever | 22 | 83 | 0.83 (0.32–2.18) | 1.0 |
| Fatigue | 26 | 83 | 0.76 (0.69–0.85) | 0.01 |
| Chills | 17 | 63 | 1.13 (0.55–2.34) | 0.73 |
| Myalgia or arthralgia | 14 | 71 | 0.59 (0.30–1.16) | 0.13 |
| Nausea or vomiting | 15 | 28 | 2.70 (1.38–5.35) | < 0.01 |
| Lightheaded or dizzy | 10 | 28 | 1.48 (0.74–2.96) | 0.28 |
| Diarrhea | 10 | 10 | 3.37 (1.80–6.34) | < 0.01 |
| Rash | 6 | 20 | 1.18 (0.53–2.63) | 0.69 |
| History of tick bite | 7 | 46 | 0.52 (0.24–1.15) | 0.99 |
| Length from symptom onset to treatment start > 7 days | 19 | 51 | 2.35 (1.01–5.48) | 0.03 |
| Parasitemia > 10% (n) | 7 | 1 | 2.14 (1.21–3.77) | 0.04 |
| WBC × 103/μL (n) | (24) | (89) | ||
| < 5.0 | 4 | 43 | 0.28 (0.10–0.77) | < 0.01 |
| > 10.0 | 4 | 4 | 2.14 (1.21–3.77) | 0.04 |
| Hb < 12.0 g/dL (n) | 14 (25) | 40 (88) | 1.39 (0.69–2.79) | 0.35 |
| Platelets < 150 × 103/μL (n) | 22 (26) | 69 (87) | 2.02 (0.55–7.48) | 0.29 |
| Na < 135 mmol/L (n) | 18 (24) | 43 (81) | 2.16 (0.94–5.01) | 0.06 |
| Creatinine > 1.2 mg/dL (n) | 10 (24) | 17 (80) | 2.04 (1.03–4.03) | 0.04 |
| ALT > 54 U/L (n) | 1 (23) | 6 (75) | 0.59 (0.09–3.76) | 0.55 |
| AST > 40 U/L (n) | 17 (23) | 54 (78) | 1.20 (0.52–2.74) | 0.67 |
| ALP > 147 units/L (n) | 4 (22) | 14 (73) | 0.95 (0.37–2.47) | 1.0 |
| Total bilirubin > 1.9 mg/dL (n) | 14 (23) | 9 (72) | 4.87 (2.43–9.74) | < 0.01 |
| Albumin < 3.4 g/dL (n) | 18 (23) | 44 (73) | 1.97 (0.80–4.85) | 0.14 |
| CRP > 3.0 mg/dL (n) | 12 (12) | 23 (28) | 0.66 (0.52–0.83) | 0.30 |
| Multivariate analyses | ||||
| OR (95% CI) | P value | |||
| WBC < 5.0 × 103/μL | 0.18 (0.04–0.77) | 0.02 | ||
| Total bilirubin > 1.9 mg/dL | 11.37 (3.43–37.73) | < 0.01 | ||
ALP = alkaline phosphatase; ALT = alanine aminotransferase; AST = aspartate aminotransferase; CRP = C-reactive protein; CI = confidence interval; Hb = hemoglobin; OR = odds ratio; RR = relative risk; WBC = white blood cell.
Bold values indicate significance.