#4852 LATE REFERRAL OF PATIENTS WITH AN UNKNOWN CAUSE OF CHRONIC KIDNEY DISEASE AND MALIGNANT HYPERTENSION

Abstract

Abstract Introduction Systemic sclerosis (SS) is a rare connective tissue disorder characterized by widespread vascular dysfunction and progressive skin and internal organ fibrosis. Scleroderma renal crisis (SRC) is a life-threatening complication of SS. The estimated incidence of SSc is approximately 20 cases per million per year, and SRC affects about 5-15% of those patients. Case Description A 32-year-old female was admitted to the hospital with dyspnea, edema, HTN, COPD. 4 months before the hospitalization, she had an abrupt onset of HTN (230/120 mm/Hg) and seizures (no abnormal waveforms on EEG). Vital signs: HR 90’, RR 22’, BP 197/121 mmHg, SpO2 90% on room air. PEx: severe jugular venous dilation, crackles in both lungs, 3+ pitting edema bilaterally. The skin appeared abnormal with a modified Rodnan score “9” out of “51” with puffy hands, sclerodactyly, telangiectasia, and Raynaud's phenomena. Lab: creatinine 406 mcmol/L, urea 20.8 mmol/L, T.Ca 2.04 mmol/L, P 1.71 mmol/L, PTH 255.5 pg./mL, Alb 33 g/L, LDH 596 U/L. Urinalysis: UPCR of 4.169 mg/mg creat. microhematuria ANA were positive for centromere pattern with a titer of >400 AU/mL (N <40), CENP-B +++, negative for anti-Scl70, anti-dsDNA, ANCA, Anti-GBM, anti-CCP, RF, anti-Jo1 and anti-Smith antibodies. A kidney biopsy showed acute tubular injury in the early stage, and later stages of interstitial fibrosis and tubular atrophy; chronic active thrombotic microangiopathy (TMA), vascular abnormalities including intimal accumulation of myxoid material, thrombosis, fibrinoid necrosis consistent with Scleroderma Renal Crisis (Fig.3; 4; 5; 6; 7) The patient started treatment with losartan 100mg. 3 months later she started hemodialysis due to diuretic refractory overhydration with severe pulmonary edema resulting in multiple hospital readmissions. Discussion SRC is a dreaded complication of systemic sclerosis that is characterized by new-onset malignant hypertension and progressive acute renal failure, often with associated microangiopathic hemolytic anemia and thrombocytopenia, occurring in ≈ 5–15% of cases, of which 2% occur with the Limited cutaneous systemic sclerosis (lcSS) and 12% in the Diffuse cutaneous systemic sclerosis (dcSS). Histopathologically SRC can be divided into narrowly defined nd-SRC and SSc-associated TMA: nd-SRC is a typical type of SRC, which shows acute renal failure and abrupt onset of moderate-to-significant hypertension. The pathology of nd-SRC shows injured endothelial cells and subsequent intimal thickening in the arcuate and interlobular arteries. The pathology of SSc-TMA shows abnormalities in the capillary wall which eventually leads to microvascular thrombosis. Our case demonstrates severe damage to the kidney, presenting with combined nd-SRC and SSc-TMA, inevitabley leading to irreversible changes resulting in CKD. Notably, until the kidney histopathology workup, neither clinical presentation nor lab tests revealed typical TMA. SRC was at one time almost uniformly fatal, with death often occurring within a few weeks. With the development of ACE-I, survival has improved dramatically, but death rates remain unacceptably high. Unfortunately, some will require chronic dialysis. However, when timely and appropriately managed, renal function can improve considerably, although it may take several months to years, allowing for discontinuation of dialysis. Conclusion SSc should be considered in any patient presenting with malignant hypertension and AKI. SRC can occur in patients without evidence of skin thickening or other manifestations of SSc. Early diagnosis improves outcome. Kidney biopsy should be gold standard in all patients with ``unknown'' causes of the CKD. ACEi remains the cornerstone of the treatment. Renal Transplantation: to discuss after two years after start of dialysis.