Acute tubulointerstitial nephritis, treatment with steroid and impact on renal outcomes

The use and timing of steroids in the management of acute tubulointerstitial nephritis (ATIN) remains debatable.

To determine the incidence and aetiology of ATIN in our unit, and to examine trends in the use of steroids and their impact on renal outcomes.

Patients with a histological diagnosis of ATIN over a 9-year period were identified and divided into steroid-treated (StG) and steroid-naïve groups (SnG). Mean change in estimated glomerular filtration rate (eGFR) was determined.

Forty-nine patients had ATIN as their main diagnosis, 67% of cases were drug-induced, and proton pump inhibitors (PPI) were the second commonest implicated drug category. Majority (75%) of patients received steroids, and eGFR improved to a significantly greater degree in these steroid-treated patients (3.4-fold improvement vs 2.0-fold in SnG; P < 0.05, unpaired t-test). Despite comparable eGFR at presentation (StG: 11.7; SnG: 15.4), steroid-treated patients were less likely to receive dialysis, although not significantly so (OR 0.27; 95% CI 0.06-1.15, P = 0.066, chi-squared test). However, there was no significant relation between the degree of eGFR improvement and delay in starting steroids (Pearson r = -0.25, P > 0.45), and no difference in eGFR at the time of last follow-up (StG: 33 ± 3; SnG: 32 ± 7; P > 0.9, unpaired t-test).

StG patients had a greater degree of improvement in renal function, but with no correlation between degree of improvement in eGFR and delay in starting steroids, and similar eGFR values at final follow-up. PPI were the second commonest drug category among drug-induced cases.