Acute Renal Failure Due to Cast Nephropathy without Multiple Myeloma

We report a 64 year-man with acute renal failure on top of hischronic renal disease due to diffuse diabeticglomerulosclerosis. Serum creatinine had reached 600umol/L from a baseline of 160 umol/L 4 months ago. Kidneybiopsy revealed diffuse broad casts obstructing the distaltubules with interstitial fibrosis associated with cast’sextravasation. The casts stained positive with kappa and notlambda indicating their monoclonal origin. The patient did nothave evidence of lymphoprolifertive disease and myeloma inparticular with normal skeletal survey and bone marrowtrephine biopsy. Moreover, serum protein and urineelectrophoresis failed to show monoclonal band. Only, directserum testing for free light chain confirmed high Kappa andnormal Lambda levels. The patient already had improved oncorticosteroids and subsequently Melphalan was added.Serum creatinine decreased to 180 umol/L by the end of this6-month treatment. The case illustrates a unique presentationof cast nephropathy without overt lymphoprolifertive disorderand with normal serum as well as urine proteinelectrophoresis. It emphasizes the need for kidney biopsyand/or direct measurement of serum free light chains fordefinitive diagnosis in such covert cases.

Clinicopathological characteristics of renal light chain deposition disease coexisted with cast nephropathy / 中华肾脏病杂志

Objective To investigate the clinicopathological characteristics of renal light chain deposition disease coexisted with cast nephropathy (LCDD&LCN).Methods Patients with LCDD&LCN (n=10),isolated LCDD (I-LCDD,n=21) and isolated LCN(I-LCN,n=17) diagnosed byrenal biopsy in Peking University First Hospital from January 1,2000 to March 31,2018 were enrolled,and all cases were examined by light microscopy,immunofluorescence (IF) (including light chain) and electron microscopy (EM).The semi-quantitative evaluation of the main features of renal pathology was performed.The clinical manifestations and pathological features were reviewed and compared.Results LCDD&LCN was more prevalent in middle-aged males.Nine patients showed acute renal insufficiency with small molecular proteinuria (97.1％) and microscopic hematuria.The hematologic diseases included 9 patients of multiple myeloma.The type of monoclonal light chain in serum and urine by immunofixation electrophoresis showed λ dominant (5/8).By light microscopy,glomerular lesions presented with mild mesangial proliferation in most patients,and only one of them displayed mesangial nodular sclerosis.At the same time,acute tubular injury with light chain casts was the prominent feature,and the clinical manifestations and histological features of LCDD&LCN were similar to that of I-LCN.IF revealed linear staining of monoclonal light chain along the glomerular basement membrane (GBM),tubular basement membrane (TBM) and Bowman's capsule,and also positive in tubular casts.By electron microscopy,diffuse powder-like or granular electron-dense deposits located in the inner side of the GBM,the outer layer of the TBM,renal interstitium and arteriolar walls were observed.Conclusions Patients with LCDD&LCN manifest as acute renal insufficiency,and the majority have multiple myeloma.The pathology of LCDD&LCN possesses the features of both I-LCDD and I-LCN.The IF stain of light chains(κ,λ) and ultrastructural examination by electron microscopy are the inevitable methods for the diagnosis of LCDD&LCN.

Application of blood purification in renal impairment of multiple myeloma / 基础医学与临床

Renal impairment is common in multiple myeloma .Besides effective chemotherapy , direct removal of se-rum free light chain by plasmapheresis or high cut-off hemodialysis is also important in the treatment of renal im-pairment in multiple myeloma .Based on results of the randomized controlled trials , the role of plasmapheresis in treating renal disease of multiple myeloma is debated .On the other side , high cut-off hemodialysis is novel and re-cently developed .Many studies have shown its potential function to further increase renal response rate when com -bined with chemotherapy .

Myeloma Kidney – A Treatable Yet Often Forgotten Disease

Multiple myeloma is a blood dyscrasias that accounts of almost 10% of all hematological malignancy. The presentation of myeloma kidney is highly variable and it often presents as renal insufficiency, renal tubular dysfunction and proteinuria of various types. In Malaysia the true incidence of myeloma kidney is unknown. Often the diagnosis of myeloma kidney was missed out despite the patient has sought medical treatment early. A high index of suspicion is required when the middle to elderly age patients present with unexplained renal impairment and enlarged kidneys. We present here the presentation of a rare subtype of myeloma in a relatively young patient whereby the patient presented with nephrotic syndrome and azotemia.

Unique morphology of intratubular light chain casts in multiple myeloma: The amyloid cast nephropathy.

Cast nephropathy is the most frequent pattern of renal involvement in multiple myeloma characterized by presence of tubular casts with characteristic morphology that are composed of monotypic (either kappa or lambda) light chains as seen by immunofl uorescence microscopy. Rarely these casts may show evidence of amyloidogenesis and assume a unique morphology, which needs to be appreciated for arriving at accurate diagnosis. We present the case of an elderly male presenting with features of acute kidney injury and detected with extensive inspissation of intratubular casts with lambda light chain restriction and a unique morphology with spiculated congophilic periphery. Further investigations confi rmed the presence of systemic myeloma. Presence of intratubular amyloid casts is a rare occurrence which needs to be recognized by the pathologist and forms a vital element in timely diagnosis of the systemic disease which often presents with renal involvement.

The value of proteinuria analysis in multiple myeloma patients with renal involvement / 医学研究生学报

Objective:To analyze and compare the clinicopathological characteristics in low weight proteinuria(LWP) and nephrotic proteinuria(NP) multiple myeloma(MM) patients with renal involvement.Methods:From October 1991 to October 2005,46 patients with MM were diagnosed in the Research Institute of Nephrology of Jinling Hospital(Nanjing,China).Renal biopsies were done in 41 of them.The patients were devided into two groups,LWP and NP groups.Their clinical and pathological features were investigated and compared. Results:The epidemiological features and type of MM in LWP and NP groups were similar.The patients in LWP group had higher incidence of D-S Ⅲ stage and heavier anaemia compared to NP group.Compared to patients in NP group,patients in LWP group had higher incidence of renal insufficiency and lower urine osmotic pressure.Part of patients checked urine N-acetyl-?-glucosaminidase,RBP and there were no difference between two groups.Cast nephropathy was the most frequent pathologic type in LWP group,while light chain deposition disease and glomerular amyloidosis were the most common pathologic type in NP group.Conclusion:According to this study,we get the conclusion that proteinuria analysis may be a significant test to evaluate the clinicopathological characteristics of MM patients with renal involvement.