Erdheim-Chester disease (ECD) is a rare systemic histiocytic infiltrative disease of unknown aetiology “Veyssier-Belot C-1996″ . The prognosis is extremely variable and is often worse when there is a cardiovascular and/or central nervous system involvement. Nephrologists are intersted in polyuropolydipsic syndrome, deterioration of renal function parameters or hydronephrosis evidence “Mounach A 2010” . Sometimes a significant abdominal and retroperitoneal infiltration doesn’t produce changes in renal function.
A 60-year-old female, suffering from diabetes mellitus, on metformin therapy, was admitted for fever, abdominal pain, diarrhoea, and acute renal failure (creatinine 19 mg/dL). For two years, she had suffered from ECD, diagnosed in another medical ward. She had undergone interferon therapy with stability of her clinical status. Since the diagnosis, she had bilateral hydronephrosis, however, she had never suffered from impaired renal function. At admission: leukocytes 21.500/μL; platelet 54.000/μL; Hb 11 g/dL; pH 7.05; HCO3–9 mEq/L; serum lactates 6 mEq/L. Findings on other routine laboratory examinations were within the normal range. Renal ultrasound showed a bilateral hydronephrosis, more to the right side. A percutaneous nephrostomy was placed to the right side; the patient received antibiotic and saline solution therapy with progressive improvement of her clinical status (remission of fever, recovery of diuresis; normalization of renal function and acid-base balance); blood and urine cultures were negative for bacterial growth. We diagnosed intestinal discomfort and lactic acidosis metformin associated with acute renal failure secondary to dehydration. Upon the complete normalization of renal function (creatinine 1.16 mg/dL), a computed tomography scan with contrast showed a slight hydronephrosis on the right side (Figura 1) and a marked hydronephrosis on the left side (Figura 2). We decided to remove the percutaneous nephrostomy; we counseled a wait-and-see policy in the outpatient clinic. We counseled ureteral stenting in cases of hydronephrosis or deterioration of renal function.
ECD is a multisystemic and heterogeneous clinicopathological condition. The natural evolution of ECD is variable, but the spontaneous prognosis is severe. We describe a case of acute renal failure and metformin-associated lactic acidosis, successfully resolved. The highlighted hydronephrosis has focused our efforts towards this renal involvement. In view of ECD course, we felt in this case the advice of a wait-and-see policy.