Table 2.

Clinical and histologic findings according to recovery of kidney function at month 6

VariablesGlobal n=182Complete Recovery n=75Partial Recovery n=83Nonrecovery n=24P Value
Baseline characteristics
 Age, yr (n=182)67±1462±1771±1067±11<0.001
 Sex (men), n (%)91 (50)34 (46)43 (51)14 (58)0.55
 Baseline Scr, mg/dl (n=182)1.07±0.361.1±0.31.1±0.41.2±0.50.32
 No CKD, n (%)109 (60)43 (58)49 (58)17 (72)0.7
 CKD stage 3, n (%)69 (39)29 (39)31 (37)5 (26)
 CKD stage 4, n (%)4 (2)2 (3)1 (1)1 (5)
 Peak Scr, mg/dl (n=182)5.7±3.55.6±4.35.2±2.47.4±3.40.02
 Skin rash, n (%) 14 (8)5 (7)7 (8)2 (8)0.92
 Fever, n (%)33 (18)15 (20)13 (16)5 (21)0.87
 Peripheral eosinophilia (>500 eosinophils/mm3), n (%)45 (25)13 (17)26 (31)6 (25)0.07
 Proteinuria, g/g (n=182)a0.7 (0.3–1.6)0.8 (0.4–1.6)0.5 (0.2–1.3)1.2 (0.4–2.6)0.07
 Proteinuria >3.5 g/g, n (%)6 (3)1 (2)2 (2)3 (12)0.19
 Microhematuria, n (%)99 (54)41 (55)42 (50)16 (67)0.34
 Leukocytosis, n (%)135 (74)54 (72)68 (82)13 (54)0.09
 Acute KRT, n (%)35 (19)14 (19)12 (14)9 (37)0.04
 Outpatients, n (%)151 (83)61 (81)69 (83)21 (87)0.76
Etiology, n (%)
 Antibiotics/antiviral (n=41)41 (22)17 (23)19 (23)5 (21)0.89
 NSAIDs (n=49)49 (27)24 (32)20 (24)5 (20)
 PPIs (n=8)8 (4)2 (3)4 (5)2 (8)
 Other drugs (n=30)30 (16)13 (18)14 (17)3 (12)
 Unknow drug (n=54)54 (30)19 (26)26 (31)9 (37)
Histology, n (%)
 Interval between drug-induced AIN diagnosis and kidney biopsy, da11 (6–22)9 (5–16)11 (6–22)18 (10–37)0.31
 Fibrosis<0.001
  <25%88 (48)44 (59)38 (46)6 (25)
  25%–50%51 (28)19 (26)28 (33)4 (17)
  50%–75%38 (21)10 (13)14 (17)14 (58)
  >75%5 (3)2 (3)3 (4)0 (0)
 Tubular atrophy0.003
  <25%81 (44)36 (49)41 (49)4 (17)
  25%–50%58 (32)26 (35)25 (30)7 (29)
  50%–75%36 (20)12 (16)12 (14)12 (50)
  >75%7 (4)1 (1)5 (6)1 (4)
 Glomerulosclerosis, %15±1412±117±1619±150.03
 Granulomas8 (4)4 (5)2 (2)2 (9)0.35
  • Complete recovery: Scr at 6 months did not exceed baseline Scr by >25%. Partial recovery: Scr at 6 months exceeded baseline Scr by 25%–75%. Nonrecovery: Scr at 6 months exceeded baseline Scr by >75% or required maintenance dialysis. Scr, serum creatinine; NSAIDs, nonsteroidal anti-inflammatory drugs; PPIs, proton-pump inhibitors; AIN, drug-induced acute interstitial nephritis; KRT, kidney replacement treatment.

  • a Median (interquartile range).