SP104RENAL HISTOLOGY IN THE SETTING OF TB IRIS

Abstract

INTRODUCTION: There is a paucity of information regarding tuberculosis immune reconstitution inflammatory syndrome [TB-IRIS] in HIV. This study aimed to describe clinical, biochemical and histopathological features of renal TB-IRIS, and assessed mortality and renal outcomes. METHODS: This observational cohort study reviewed HIV positive renal biopsies with granulomatous interstitial nephritis [GIN] from two registries between 2009-2015. The cohort was evaluated for evidence of tuberculosis [TB] and thereafter features of clinical TB-IRIS. Three groups were identified and compared i.e. [TB: no IRIS], [TB+IRIS] and [Other] (Gin no evidence of TB). A comparison of renal function at one year and survival at 2 years was made between IRIS and non-IRIS cohorts. RESULTS: There were 68/421 HIV-positive renal biopsies identified with GIN. The mean age was 37.5±9.1 years. TB accounted for 47(69.1%) and of these, 19 (40%) had TB-IRIS. TB-IRIS was characterised by a short duration after antiretroviral therapy [ART] (p=0.028) with a median of 6 (4-9) weeks post initiation and demonstrated well-formed granulomas (p=0.068) on biopsy. Proportion of acute kidney injury [AKI] was similar in TB (21.3%), TB-IRIS (21.1%) and Other(23.8%). Seventeen(25%) of the total GIN cohort died within 2 years of their biopsy, (12/48, 44%) of deaths occurred in the [TB: no IRIS] group, (P-value 0.01). CONCLUSIONS: Renal TB-IRIS should be considered in the presence of well-formed granulomas on biopsy and a short duration of ART initiation. TB-IRIS wasn't associated with an increased proportion of AKI compared to GIN alone. It demonstrated improved survival with no worse long term renal sequelae.