Sarcoidosis-Associated Immune Thrombocytopenic Purpura and Focal Segmental Glomerulosclerosis

ABSTRACT

Purpose of study A 32-years old male with known multi-system sarcoidosis in remission for 5 years off treatment presented to the emergency room with complaints of generalized weakness, hematemesis, epistaxis, and bruises. Physical examination was notable for petechiae, ecchymosis along with papules and plaques suggestive of active sarcoid skin lesions on his extremities. Laboratory workup was significant for thrombocytopenia 3000/uL, acute kidney injury with sub-nephrotic proteinuria. Peripheral blood smear did not show evidence of hemolysis and direct Coombs test was negative. Infectious workup including COVID-19, HIV, and hepatitis serologies were negative. Computed Tomography (CT) of chest, abdomen, and pelvis showed mild splenomegaly and an increased number of sub-centimeter hilar and mediastinal lymph nodes. The patient was treated with dexamethasone 40 mg daily for 4 days and intravenousimmunoglobulins (IVIG-2 gm/kg) for possible Immune Thrombocytopenic Purpura (ITP) with improvement in platelet count to 42000/uL by day 3. His workup for AKI and sub-nephrotic proteinuria was negative apart from a positive ANA (1 160) with low complements. The anti-phospholipid antibody panel was negative. The ACE level was markedly elevated (>80U/L). The patient could not get a renal biopsy due to severe thrombocytopenia. He was discharged but was re-admitted in 15 days for severe thrombocytopenia of 1000/uL, epistaxis, and bruising. We continued high dose steroids along with IVIG 1 gm/kg for refractory ITP with minimal response and started anti-CD20 agent (Rituximab) 375 mg/m2 weekly with thrombopoietin-receptor agonist (Eltrombopag). His platelets count improved in response to treatment and subsequent renal biopsy showed focal and segmental glomerulosclerosis along with mild interstitial fibrosis, tubular atrophy thought to be from long standing sarcoidosis. There was also evidence of focal arteriosclerosis with no evidence of granulomas, immune complex, complement, or IgG4 deposition. Given skin lesions, thrombocytopenia, extensive lymphadenopathy, and renal involvement with markedly elevated ACE levels the overall picture was consistent with active multi-system sarcoidosis. His platelet count increased to 177,000/uL at the time of discharge. Currently, the patient is on slow steroid taper along with Eltrombopag 25 mg every other day without any recurrence of his symptoms so far. Methods used We described one case of sarcoidosis with hematologic and renal involvement. Summary of results Our patient developed hematologic and renal complications approximately 6 years after being diagnosed with sarcoidosis. Initially, he did not demonstrate sufficient clinical response to IVIG and high dose steroids. However, after a course of anti-CD20 agent (Rituximab) and with the addition of thrombopoietin-receptor agonist (Eltrombopag) he showed improvement of platelet count and stabilization of the renal function. Currently, the patient is receiving maintenance therapy with Prednisone 7.5 mg daily along with Eltrombopag 25 mg twice weekly with no recurrence of ITP and stable renal function. A further decision on whether the patient needs another cycle of Rituximab will be determined by the patient's clinical course. Conclusions Highly variable manifestations of Sarcoidosis can pose a significant diagnostic and therapeutic challenge as can be seen from our case. ITP is a rare hematological manifestation of sarcoidosis and addition of anti-CD20 agents should be considered in refractory cases.