Case 1
A 52-year-old woman was admitted to our nephrology department for management of renal failure. She was operated on for a renal tumor of the left kidney a month ago. Histological examination showed tubulo-papillary carcinoma (Fig1, 2). Several non necrotizing granulomas were seen around the tumor. Granulomas formation did not contain malignant cell. Specific stain for mycobacterial organisms (Ziel-Neelson stains) was negative.
Otherwise, the patient had complained of unexplained cough one year ago. Clinical examination revealed erythema nodosum. Laboratory tests showed lymphopenia, high serum calcium level, normal serum parathyroid hormone level, renal failure (creatinemia: 2.3 mg/dl), high CRP levels (65 mg/l) and elevated serum angiotensin-converting levels). Chest computed tomography (CT) did not suggested tuberculosis but it revealed mediastinal lymph node enlargement. The broncho-alveolar lavage with cell count revealed 20 % of lymphocytes with a ratio CD4/CD8 lymphocyte ratio equal to 3.6. The diagnosis of active sarcoidosis with renal, lung and skin involvement was made. After initiation of 1 mg/kg/day of prednisone, clinical manifestations gradually disappeared. Laboratory tests have shown a drop in serum calcium and CRP levels. Chronic renal failure has remained stable.
Case 2- A 17-year-old female with a clinical history of sarcoidosis with skin, lung, renal and neurological involvement was referred to nephrology department for progressive renal failure and uncontrolled hypertension under corticosteroid therapy. Clinical examination showed hepatomegaly, erythema nodosum, multiple peripheral lymphadenopathy and peripheral facial paralysis. Her blood pressure was of 180/ 90 mmHg. Laboratory tests showed lymphopenia. Serum creatinine level was 3.6 mg/dl and proteinuria was 1.2 g/24 hours. She had pulmonary involvement with bilateral hilar lymphadenopathy on chest CT. The bronchoalveolar lavage revealed a lymphocyte ratio CD4:CD8 equal to 3.7. Cerebral MRI showed hyperintensity of white matter consistent with neurological involvement of sarcoidosis. Renal ultrasound revealed kidney asymmetry with a smaller and hyper echogenic right kidney. A CT-guided needle biopsy of the left kidney demonstrated several non-necrotizing epithelioid granulomas (Fig 3). Despite immunosuppressive therapy (Azathioprine at a dose of 100 mg a day and a prednisone at a dose of one mg/kg/day) kidney function gradually worsened. On the other hand, hypertension remained uncontrolled in spite of antihypertensive therapy and salt free diet.
As part of etiological assessment of hypertension, retrograde urethro-cystography was performed without abnormalities. Doppler ultrasonography of the renal artery didn’t show any stenosis. DMSA renal scintigraphy revealed impaired relative right renal function (14% in right kidney vs 86% in left kidney). Aldosterone/direct Renin concentration ratio was < 30, consisting with secondary hyperaldosteronism. A total right nephrectomy was performed. Histological examination of the nephrectomy specimen showed a multifocal tubulocystic carcinoma without sarcoïd granuloma (Fig4). Despite well-managed medical treatment, the patient progressed to end-stage renal failure. At 5-years follow-up, the patient was on chronic dialysis without recurrence of neoplasia.