Sarcoidosis induced interstitial nephritis. A case series with literature review

Abstract

Sarcoidosis is an idiopathic multisystem granulomatous disease that has been postulated to be autoimmune etiology [1]. Incidence and prevalence of sarcoidosis is variable depending on geographic region and has been reported as 10 per 100,000 per year [2-4]. Highest incidence has been noted in the African American population [5]. Diagnosis is mostly dependent on a biopsy of an involved organ showing non-caseating granulomas as there is no reliable test to rule in or rule out this disease [6]. Lungs are most commonly involved but extra pulmonary manifestations have also been reported. Renal manifestation secondary to sarcoidosis are mostly due to hypercalcemia and hypercalciuria leading to nephrocalcinosis but clinically apparent renal failure is less common [1]. We present 3 cases of renal failure secondary to sarcoidosis and all them had features of interstitial nephritis on renal biopsy. Apart from the cases presented, we reviewed all cases of sarcoidosis induced interstitial nephritis reported from 2013 to 2018. There was a total of 13 case reports found that were reviewed. Sarcoidosis induced interstitial nephritis without granuloma formation has not been reported in the past 5 years which was observed in one of our cases. Once this condition is diagnosed, steroids with and without immunosuppressive agents play important role in the prognosis of renal sarcoidosis to prevent end stage renal disease (ESRD) [1,6].