POS-475 GRANULOMATOUS INTERTITIAL NEPHRITIS : A SERIE OF FIVE PATIENTS

Abstract

Granulomatous interstitial nephritis (GIN) is a rare histologic diagnosis.The cause is often difficult to establish and the studies are limited.This serie reported the presenting features, associated conditions, treatment, and outcomes of patients with a diagnosis of GIN. From 2005 to 2020 , we analysed cases of acute intertitial nephritis in the departement of nephrology of Fatouma Bourguiba Monastir University Hospital. From 17 cases of acute intertitial glomerulonephritis, five patients had granulomatous interstitial nephritis : three cases were associated with sarcoidosis, two were idiopathic. All the patients were femele.The median age of patients was 57 years [34- 77 years]. All patients presented with advanced renal failure (median estimated creatinine clearance 9 ml/min) and minimal proteinuria ( the mean was 0.9 g/day ) without hematuria. Hypercalcemia was present in 2 patients. Pulmonary involvement was present in one case, uveitis and pancreatitis were identified respectively in two cases and one case. Renal biopsy revealed granulomatous interstitial nephritis lesions in all patients. Corticosteroid therapy using prednisolone 1 mg/kg per day was used in all patients. Two patients had methylprednisolone pulse before oral corticosteroid therapy. MMF was associated with corticosteroids in one case. All patients improved their renal function. The median estimated creatinine clearance was 25 ml/min after 6 months. Two patients had normalized their renal fonction. Granulomatous interstitial nephritis may be the first manifestation of a systemic disease . Histologic features do not seem to distinguish the underlying cause of GIN. Corticosteroids therapy seems to be efficient and must be introduced early to prevent progression to chronic renal failure and it is associated with a good prognosis.