Table 3.
Baseline characteristics of idiopathic or drug-induced acute tubulointerstitial nephritis
| Variable | All subjects (n = 102) | Steroid-treated group (n = 82) | Non-treated group (n = 20) | P-valuea |
|---|---|---|---|---|
| Age (year) | 58.6 ± 14.9 | 58.1 ± 15.4 | 60.6 ± 13.0 | 0.501 |
| Female (%) | 41.2 | 39.0 | 50.0 | 0.371 |
| Body mass index (kg/m2) | 23.4 ± 3.5 | 22.9 ± 3.4 | 25.4 ± 3.3 | 0.005 |
| Comorbidities (%) | ||||
| Diabetes mellitus | 31.4 | 29.3 | 40.0 | 0.354 |
| Hypertension | 42.2 | 37.8 | 60.0 | 0.072 |
| Chronic kidney disease | 11.8 | 7.3 | 30.0 | 0.012 |
| Blood findings | ||||
| Peak sCr (mg/dL) | 4.57 (3.04–7.23) | 4.67 (3.00–7.46) | 4.43 (4.06–6.05) | 0.879 |
| sCr at biopsy (mg/dL) | 3.73 (2.70–5.80) | 3.89 (2.51–6.10) | 3.40 (3.09–4.05) | 0.458 |
| Hemoglobin (g/dL) | 10.0 ± 1.6 | 10.5 ± 1.7 | 9.9 ± 1.6 | 0.201 |
| Cholesterol (mg/dL) | 140.0 (121.0–167.0) | 140.0 (121.0–166.0) | 144.0 (122.0–186.0) | 0.820 |
| Uric acid (mg/dL) | 6.1 (4.6–8.0) | 5.9 (4.1–7.5) | 7.5 (6.2–9.9) | 0.005 |
| Albumin (g/dL) | 3.5 (3.1–3.9) | 3.5 (3.1–3.9) | 3.2 (2.9–4.0) | 0.280 |
| Proteinuria (%) | 0.116 | |||
| - or trace | 28.4 | 24.4 | 45.0 | |
| 1+ | 33.3 | 36.6 | 20.0 | |
| 2+ | 25.5 | 28.0 | 15.0 | |
| ≥ 3+ | 12.7 | 11.0 | 20.0 | |
| Hematuria (%) | 41.2 | 37.8 | 55.0 | 0.161 |
| Pyuria (%) | 57.8 | 56.1 | 65.0 | 0.470 |
| uPCR (g/g) | 1.2 (0.7–2.5) | 1.3 (0.7–2.4) | 0.9 (0.7–4.2) | 0.676 |
| Dialysis at biopsy (%) | 29.4 | 30.5 | 25.0 | 0.629 |
| TA/IF (%) | 0.024 | |||
| None | 13.7 | 12.2 | 20.0 | |
| Milde | 34.3 | 37.8 | 20.0 | |
| Moderate | 40.2 | 42.7 | 30.0 | |
| Severe | 11.8 | 7.3 | 30.0 | |
| Leukocyte infiltration (%) | 0.514 | |||
| Mild | 17.6 | 15.9 | 25.0 | |
| Moderate | 38.2 | 37.8 | 40.0 | |
| Severe | 44.1 | 46.3 | 35.0 | |
| Follow-up duration (months) | 34 (19–55) | 34 (18–54) | 27 (21–69) | 0.508 |
aP-value was obtained from the Student’s t-test or the Mann-Whitney test