BANTAO Journal 2016; 14(2): 89-91; DOI:10.1515/bj-2016-0021 ________________________ Correspondence to: Lutfiye Bilge Caliskan, Department of Internal Medicine, Tepecik Educational and Research Hospital, Izmir, Turkey; E-mail: harunakar.md@gmail.com 89 BJ BANTAO Journal Case report A Case of Multiple Myeloma Diagnosed by Renal Biopsy Lutfiye Bilge Caliskan 1 , Tugba Karadeniz 2 , Sumeyye Ekmekci 2 , Banu Yilmaz Avcioglu 3 , Mehmet Tanrisev 3 , Muhammed Ali Kaypak 1 , Hakan Yarkici 1 , Cengiz Ceylan 4 and Harun Akar 1 1 Department of Internal Medicine, 2 Department of Pathology, 3 Department of Nephrology, 4 Department of Hematology, Tepecik Educational and Research Hospital, Izmir, Turkey Abstract Multiple myeloma is a malignant disease that results in the proliferation of a single plasma cell clone. The cli- nical manifestations are anemia, bone pain, bone fractu- res, hypercalcemia, hypergammaglobulinemia, increased erythrocyte sedimentation rate, rouleaux formation on the peripheral blood smear and rarely increased serum vis- cosity. Rarely cast nephropathy associated with acute re- nal failure may be the first finding of multiple myeloma. We report a clinical case of a 44-year-old female patient who presented with acute renal failure due to cast neph- ropathy without myeloma’s typical clinical and labora- tory findings. In the clinical case presented here, we high- light that multiple myeloma can be presented with acute renal failure and without any other typical symptoms. Keywords: Multiple myeloma, renal biopsy ______________________________________ Introduction Plasma cell dyscrasias result from a clonal expansion of neoplastic plasma cell. In general, plasma cell dyscrasia can be detected by the presence of one of the following findings: monoclonal light chain in the serum by immu- nofixation electrophoresis (SIFE), monoclonal light chain in the urine by immunofixation electrophoresis (UIFE), or monoclonal plasma cells in the bone marrow by immunohistochemistry [1]. The diagnosis of plasma cell dyscrasias including multiple myeloma (MM) can be done by bone marrow aspiration, biopsy and clinical la- boratory test [2]. The diagnosis of MM requires assess- ment of a Wright-Giemsa stained bone marrow aspirate and a hematoxylin and eosin stained core biopsy section [2]. Kidney injury represents one of the leading cha- racteristics of plasma cell disorders [3] and kidneys are target organs in plasma cell disorders [4]. In other words, renal function is often impaired in plasma cell disor- ders and this is due to the presence of monoclonal pro- teins [4]. Myeloma cast nephropathy is one of the most common types of kidney injury [3]. The term myeloma kidney or myeloma cast nephropathy generally refers to renal insufficiency caused by the tubulointerstitial da- mage. Myeloma-induced renal failure is associated with significant morbidity and mortality. Rapid intervention is critical in order to reverse kidney damage and improve renal function. In addition to clinical suspicion, further evaluation is often necessary. Case Report A 44-year-old woman with absent previous medical his- tory came to the outpatient clinic complaining of nausea, vomiting and weakness over a period of 2-weeks. The patient was admitted to the Department of Nephrology for evaluation. She reported no back pain and no me- dication known to be associated with renal dysfunction. The patient’s vital signs and physical examination were normal. Cardiac and pulmonary examination showed no abnormal findings. Routine laboratory tests were as fo- llows: Hgb: 9.9 gr/dl, Hct: 29%, MCV: 89.5 fl, PLT: 187.000 u/l, WBC: 10.900 u/l, glucose: 98 mg/dl, urea: 157 mg/dl, creatinine: 7.3 mg/dl, potassium: 5.5 mEq, AST: 16 U/L, ALT: 24 U/L, protein: 8 g/dL, calcium: 10.4 mg/dL, phosphorus: 5.1 mg/dL, uric acid: 4.9 mg/dl, albumin: 4g/dl, globulin: 4g/dl, T. bilirubin: 0.5 mg/dl, erythrocyte sedimentation rate: 39 mm/h. Urine examina- tion was unremarkable. Review of the peripheral smear demonsrated anisocytosis. Iron parameters and LDH were within normal limits. An abdominal ultrasound scan demonstrated normal-sized kidneys with increased echogenicity without evidence of obstruction. At the time of the evaluation, she was treated appropriately with he- modialysis. The patient underwent renal biopsy in order to elucidate the etiology of the acute renal failure. Sub- sequent pathology report revealed cast nephropathy. No lytic lesions were detected on direct radiographs. Mono- clonal lambda-free light chain was found in serum and urine immunofixation electrophoresis, and serum immu- noglobulin levels were as follows: IgA: 173 mg/dl, IgG: 1108 mg/dl, IgM: 113 mg/dl. Bone marrow aspiration