Light chain deposition disease with renal involvement: clinical characteristics and prognostic factors

How I treat monoclonal gammopathy of renal significance (MGRS)

Recently, the term monoclonal gammopathy of renal significance (MGRS) was introduced to distinguish monoclonal gammopathies that result in the development of kidney disease from those that are benign. By definition, patients with MGRS have B-cell clones that do not meet the definition of multiple myeloma or lymphoma. Nevertheless, these clones produce monoclonal proteins that are capable of injuring the kidney resulting in permanent damage. Except for immunoglobulin light chain amyloidosis with heart involvement in which death can be rapid, treatment of MGRS is often indicated more to preserve kidney function and prevent recurrence after kidney transplantation rather than the prolongation of life. Clinical trials are rare for MGRS-related kidney diseases, except in immunoglobulin light chain amyloidosis. Treatment recommendations are therefore based on the clinical data obtained from treatment of the clonal disorder in its malignant state. The establishment of these treatment recommendations is important until data can be obtained by clinical trials of MGRS-related kidney diseases.

Kidney disease and multiple myeloma

Kidney injury is a common complication of multiple myeloma and other plasma cell dyscrasias, and it is associated with increased mortality. Multiple pathogenic mechanisms can contribute to kidney injury in the patient with myeloma, some of which are the result of nephrotoxic monoclonal Ig and some of which are independent of paraprotein deposition. The pathogenic mechanisms that underlie paraprotein-related kidney disease are increasingly well understood. A novel assay allowing the quantification of free light chains in the serum has aided the diagnosis of new onset disease and allowed for the earlier detection of relapse. Novel myeloma agents have shown considerable promise in reversing renal failure in some patients and improving outcomes. Stem cell transplantation remains a mainstay of management for younger patients with myeloma who are suitable candidates for intensive therapy, whereas the role of new drugs, plasma exchange, and kidney transplantation continues to evolve.

[An unusual cause of cystic lung disease: light chain deposition disease]

INTRODUCTION

Light chain deposition disease is a rare clinical entity characterized by deposition of monoclonal immunoglobulin light chains in organs. The kidneys are almost always affected, while the lung manifestations that have been reported, including nodular or diffuse disease, especially cystic lesions, are unusual.

CASE REPORT

We report the case of a 60-year-old man with a diffuse infiltrative lung disease characterized by numerous apical cysts. The diagnosis of light chain deposition cystic lung disease was obtained by surgical lung biopsy. Light chain deposits in the salivary glands were the only extrapulmonary manifestation. Despite 12 chemotherapy cycles, the patient's lung function and radiological appearances worsened.

CONCLUSION

This is the fourth case describing a cystic lung disease due to light chain deposition in the literature. It highlights the need for comprehensive investigations so as not to miss this rare cause of cystic lung disease, which appears to be related to a primary pulmonary lymphoproliferative disorder. The only treatment that appears to be effective is lung transplantation.

Portal hypertension related to light chain deposition disease of liver: an enlightening experience

A 55-year-old alcoholic man presented with firm hepatomegaly, ascites and markedly elevated alkaline phosphatase. He had a history of pulmonary tuberculosis. Work-up for malignancy was negative. Histological examination of liver showed extracellular deposition of pink amorphous material which is Congo red stain negative. Deteriorating renal function and nephrotic-range proteinuria were noted. Renal histology showed thickening of the glomerular and tubular basement membranes by non-congophilic deposits along with mesangial expansion. Bone marrow examination revealed patchy areas of pink amorphous deposits which are Congo red stain negative. Immunohistochemical staining of amorphous depositions in liver, kidney and bone marrow were positive for κ light chains. Serum-free light chain assay confirmed markedly elevated free κ-light chain. κ-light chain deposition disease is a systemic disease with universal renal involvement but rarely it presents as chronic cholestatic liver disease with portal hypertension and frequently associated with fatal outcome due to diagnostic delay.

Retinal pigment epithelial detachments and tears, and progressive retinal degeneration in light chain deposition disease

BACKGROUND/PURPOSE

Light-chain deposition disease (LCDD) is a rare condition characterised by deposition of monoclonal immunoglobulin light chains (LCs) in tissues, resulting in varying degrees of organ dysfunction. This study reports the characteristic clinical ocular findings seen in advanced LCDD upon development of ocular fundus changes. This is the first report to describe this entity in vivo in a series of patients.

METHODS

A case series of ocular fundus changes in three patients with kidney biopsy-proven LCDD. All patients underwent best corrected visual acuity (BCVA) exam, perimetry, colour fundus photography and fluorescein angiography; two patients underwent indocyanine green angiography, optical coherence tomography, ultrasound and electroretinography; and one patient underwent fundus autofluorescence.

RESULTS

Three patients, 53-60 years old at initial presentation, were studied. All three presented with night blindness, poor dark adaptation, metamorphopsia and visual loss. Examination revealed serous and serohaemorrhagic detachments, multiple retinal pigment epithelial (RPE) tears, diffuse RPE degeneration and progressive fibrotic changes. Neither choroidal neovascularisation nor other vascular abnormalities were present. Final best corrected visual acuity (BCVA) ranged from 20/40 to 20/300.

CONCLUSIONS

Progressive LC deposition in the fundus seems to damage RPE pump function with flow disturbance between choroid and retina. This pathogenesis can explain the evolution to RPE detachments and subsequent rips and progressive retinal malfunction.

"Idiopathic Bence-Jones proteinuria": a new characterization of an old entity

Idiopathic Bence-Jones proteinuria (BJP) is a rare plasma cell dyscrasia, of which the clinical and biological characteristics are yet unclear. Historical data suggested that they are at higher risk of progression to multiple myeloma or other related neoplasms, while recent findings are contradictory. To address these open questions, we evaluated a series of both BJP and monoclonal gammopathy of undetermined significance (MGUS) with production of an intact immunoglobulin plus Bence-Jones proteinuria (MGUS+BJP) with long-term follow-up, regarding their clinical characteristics and progression to multiple myeloma, amyloidosis or other related B cell lymphoproliferative disorders. Two hundred and twenty-nine persons fulfilling the 2004 criteria of MGUS were included in the final analyses: 31 had BJP and 198 had MGUS+BJP. At the time of diagnosis, significantly more persons in the BJP group had renal impairment, anaemia and polyneuropathy. A more detailed analysis revealed discrepancies between the serum and urine light chain type in nine cases, reflecting clonal heterogeneity. The number of disease progressions was higher in MGUS+BJP (n = 30) when compared to BJP (n = 1), with a rate of 1.6 and 0.4 progressions per 100 person-years, respectively. In conclusion, BJP has distinct clinical characteristics and a lower risk of progression when compared to MGUS+BJP. Our data suggest that MGUS+BJP being closer to malignant transformation may be due to the higher portion of genetically heterogeneous, pre-malignant plasma cell subclones.

Clinical challenges of an oligosecretory plasma cell dyscrasia

Light chain deposition disease (LCDD) and immunoglobulin light chain (AL) amyloidosis are uncommon, and heterogeneous clonal plasma cell (PC) proliferative disorders defined by the different biochemical characteristics of the underlying anomalous immunoglobulin. The deposits are usually multisystemic and the two diseases can coexist. The diagnosis is sometimes made difficult by the absence of a detectable paraprotein by routine immunofixation techniques, and the use of serum-free light chain (FLC) immunoassay brought new value in terms of their diagnosis, prognosis and assessment of treatment response. Association of LCDD and AL amyloidosis with multiple myeloma (MM) at the time of diagnosis is common, but further progression to this condition is considered rare. We present a case of a patient diagnosed with systemic LCDD and AL amyloidosis of atypical biochemical characteristics, with no paraprotein detected in immunoelectrophoresis and immunofixation techniques, who progressed to MM in the later course of her disease.

Serous retinal detachments associated with light chain deposition disease

PURPOSE

To report the clinical, fluorescein angiography, spectral-domain optical coherence tomography, and fundus autofluorescence (AF) findings of a 64-year-old woman with systemic light chain deposition disease.

METHODS

Clinical examination, fundus photographs, fundus AF, spectral-domain optical coherence tomography, and fluorescein angiography before and after renal transplantation in a patient with light chain deposition disease.

RESULTS

The patient presented with decreased visual acuity in her right eye. Fundus examination showed bilateral drusenoid subretinal deposits associated with subretinal fluid. Fluorescein angiography showed staining of the lesions seen on clinical examination. Spectral-domain optical coherence tomography showed hyperreflective material below the neurosensory retina associated with subretinal fluid. Fundus AF showed areas of increased AF corresponding to the lesions. The lesions showed improvement after renal transplantation and initiation of immunosuppressive agents.

CONCLUSION

Patients with light chain deposition disease may present with subretinal deposits that can be seen clinically and demonstrated on fluorescein angiography, AF, and optical coherence tomography. They may also present with localized serious retinal detachments. Both these deposits and serous retinal detachments may improve with renal transplantation or immunosuppressive therapy.

Monoclonal gammopathy of renal significance: when MGUS is no longer undetermined or insignificant

Multiple myeloma is the most frequent monoclonal gammopathy to involve the kidney; however, a growing number of kidney diseases associated with other monoclonal gammopathies are being recognized. Although many histopathologic patterns exist, they are all distinguished by the monoclonal immunoglobulin (or component) deposits. The hematologic disorder in these patients is more consistent with monoclonal gammopathy of undetermined significance (MGUS) than with multiple myeloma. Unfortunately, due to the limitations of the current diagnostic schema, they are frequently diagnosed as MGUS. Because treatment is not recommended for MGUS, appropriate therapy is commonly withheld. In addition to end-stage renal disease, the persistence of the monoclonal gammopathy is associated with high rates of recurrence after kidney transplantation. Preservation and restoration of kidney function are possible with successful treatment targeting the responsible clone. Achievement of hematologic complete response has been shown to prevent recurrence after kidney transplantation. There is a need for a term that properly conveys the pathologic nature of these diseases. We think the term monoclonal gammopathy of renal significance is most helpful to indicate a causal relationship between the monoclonal gammopathy and the renal damage and because the significance of the monoclonal gammopathy is no longer undetermined.

Indolent systemic mastocytosis associated with light chain deposition disease

Systemic mastocytosis (SM) is characterized by infiltration of neoplastic mast cells in one or more organ systems. SM in association with plasma cell dyscrasia is very rare. We report a first case of indolent SM (ISM) associated with light chain deposition disease (LCDD) in a kidney biopsy from a 59-year-old female presenting with skin rash, elevated serum creatinine, hematuria and mild proteinuria. Subsequent workup demonstrated IgG kappa monoclonal protein in serum and urine. A bone marrow biopsy revealed neoplastic mast cells involving bone marrow without evidence of clonal myeloid or lymphoid proliferation. Kidney biopsy demonstrated modest mesangial expansion detected by light microscopy and unequivocal evidence of monoclonal kappa light chain deposition within glomerular capillaries, tubular basement membranes and vascular walls detected by immunofluorescence and/or electron microscopy, along with equivocal evidence of light chain cast nephropathy. Despite treatment with bortezomib and dexamethasone, her renal function was progressively declined over the next 6 months. This case is a reminder that SM can coincide with LCDD, which requires clinical suspicion and multimodality workup on a kidney biopsy including immunofluorescence and electron microscopy to reach the correct diagnosis.

Urinary albumin excretion patterns of patients with cast nephropathy and other monoclonal gammopathy-related kidney diseases

BACKGROUND AND OBJECTIVES

Multiple myeloma is responsible for a wide variety of renal pathologies. Urinary protein and monoclonal spike cannot be used to diagnose cast nephropathy (CN). Because albuminuria is a hallmark of glomerular disease, this study evaluated the percentage of urinary albumin excretion (%UAE) as a tool to differentiate CN from Ig light chain amyloidosis (AL), light chain deposition disease (LCDD), and acute tubular necrosis (ATN).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Patients were selected from the Renal Biopsy Database and the Dysproteinemia Database. Participants were excluded if laboratory data were missing within 1 week of the renal biopsy. The %UAE was obtained from urine protein electrophoresis.

RESULTS

From 1992 to 2011, 260 patients were biopsied (177 with AL, 28 with LCDD, 43 with CN, and 12 with ATN). The %UAE for CN patients was significantly lower (7%) than for ATN (25%), LCDD (55%), and AL (70%) patients (P<0.001). Significant differences were also found in serum creatinine, serum albumin, free light chain ratio, total urine protein, and urine monoclonal spike; only the %UAE remained independently associated with CN in a logistic regression model (P<0.001). The area under the curve for the receiver operator characteristic curve for %UAE was 0.99. At <25%, the %UAE had a sensitivity of 0.98, specificity of 0.94, positive predictive value of 0.75, and negative predictive value of 0.99.

CONCLUSIONS

This study showed that %UAE was significantly less in CN than the other three renal lesions and %UAE may thus be helpful in diagnosis of CN.

Management of myeloma-associated renal dysfunction in the era of novel therapies

Multiple myeloma (MM) is a plasma cell neoplasm often associated with renal impairment (RI), with myeloma cast nephropathy recognized as the most common cause. While RI is present in over 50% of MM patients at some point in their disease course, it is associated with higher tumor burden, more aggressive disease, diminished quality of life, development of complications and increased mortality. The introduction of novel therapies, including bortezomib, lenalidomide and thalidomide, has revolutionized the management of MM. They are now considered first-line therapies in induction, maintenance and salvage therapy for MM. In addition to their anti-MM effect, they can improve outcome in patients with RI, especially when combined, and bortezomib with dexamethasone may have a renal protective effect. This review focuses on the use of these agents in patients with MM and RI, and evaluates their efficacy, safety, need for dose adjustment and impact on RI.

Light-chain deposition disease of the kidney: a case report

A 41-year-old man was admitted for evaluation of nephrotic syndrome associated with microhematuria, hypertension, and moderate renal failure. In serum and urine samples, monoclonal IgG-lambda was detected. Bone marrow examination showed normal representation of all cell lines with normal range of plasma cells. Renal biopsy demonstrated diabetes-like nodular glomerulosclerosis. Immunofluorescence failed to demonstrate the presence of kappa or lambda light chains in the kidney. Electron microcopy showed granular electron-dense deposits along the glomerular basement membranes and in the mesangial nodules. The patient was diagnosed as having light-chain deposition disease (LCDD) without evidence of plasma cell dyscrasia. This report was designed to stress the significant challenges that remain in the diagnosis of LCDD-related glomerulopathy. The salient morphological features that help in making an accurate diagnosis are discussed.

A case of isolated light chain deposition disease in the duodenum

Light chain deposition disease (LCDD) is a rare disorder associated with a clonal proliferation of plasma cells, which synthesize abnormal monoclonal immunoglobulin light chains. LCDD is characterized by systemic deposition of light chains in various organs, with the kidneys being most commonly affected. There have been few reports of isolated LCDD. We report a rare case of LCDD limited to a duodenal polyp. A 63-yr-old man visited our hospital for health screening without symptoms in 2009. On gastrofiberscopy, a duodenal polyp was observed. The biopsy showed diffuse infiltration by atypical plasma cells, which were positive for kappa-type light chains by immunohistochemistry. While the patient refused further management, we could find no evidence of recurrence until 2 yr after the initial diagnosis. It has been reported that isolated LCDD has relatively good prognosis compared to systemic LCDD. However, treatment for this disease has not been established yet.

Renal monoclonal immunoglobulin deposition disease: a report of 64 patients from a single institution

BACKGROUND AND OBJECTIVES

To better define the clinical-pathologic spectrum and prognosis of monoclonal immunoglobulin deposition disease (MIDD), this study reports the largest series.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Characteristics of 64 MIDD patients who were seen at Mayo Clinic are provided.

RESULTS

Of 64 patients with MIDD, 51 had light chain deposition disease, 7 had heavy chain deposition disease, and 6 had light and heavy chain deposition disease. The mean age at diagnosis was 56 years, and 23 patients (36%) were ≤50 years of age. Clinical evidence of dysproteinemia was present in 62 patients (97%), including multiple myeloma in 38 (59%). M-spike was detected on serum protein electrophoresis in 47 (73%). Serum free light chain ratio was abnormal in all 51 patients tested. Presentation included renal insufficiency, proteinuria, hematuria, and hypertension. Nodular mesangial sclerosis was seen in 39 patients (61%). During a median of 25 months of follow-up (range, 1-140) in 56 patients, 32 (57%) had stable/improved renal function, 2 (4%) had worsening renal function, and 22 (39%) progressed to ESRD. The mean renal and patient survivals were 64 and 90 months, respectively. The disease recurred in three of four patients who received a kidney transplant.

CONCLUSIONS

Patients with MIDD generally present at a younger age than those with light chain amyloidosis or light chain cast nephropathy. Serum free light chain ratio is abnormal in all MIDD patients, whereas only three-quarters have abnormal serum protein electrophoresis. The prognosis for MIDD is improving compared with historical controls, likely reflecting earlier detection and improved therapies.

Screening and differential diagnosis of renal light chain-associated diseases

BACKGROUND

Renal involvement in the light chain-associated diseases multiple myeloma (MM), amyloidosis (AL) and monoclonal immune position disease (MIDD) is common and differential diagnosis usually requires renal biopsy. The aim of this study was to investigate if noninvasive methods are viable to identify and differentiate between the various types of kidney diseases.

PATIENTS AND METHODS

All patients with a light chain-associated disease admitted to our center from 1996 to 2008 were retrospectively evaluated. Renal biopsy data were correlated with proteinuria findings.

RESULTS

Only the ratio of free κ/λ light chains showed a good sensitivity for myeloma cast nephropathy (MCN), AL and MIDD. The λ light chain was characteristic for AL, the κ light chain dominated in MIDD. Renal function at the time of diagnosis was worst in MIDD. MCN presented with a proteinuria of > 3.5 g/g creatinine. In contrast, a higher proteinuria was found in AL or MIDD. Whereas the κ/λ ratio in the urine was pathological for all three diseases, extremely high or low ratios indicated the presence of MCN. However, in AL or MIDD, the ratio was only moderately elevated.

CONCLUSION

A noninvasive differentiation between MCN and other forms of renal light chain disease is possible.

Long-term reversibility of renal dysfunction associated to light chain deposition disease with bortezomib and dexamethasone and high dose therapy and autologous stem cell transplantation

A 63-year-old woman presented with progressive renal insufficiency, until a glomerular filtration rate (GFR) of 12 mL/min. A renal biopsy demonstrated glomerular deposition of immunoglobulin κlight chain. The presence of a small population of monoclonal plasmacytes producing an only light κmonoclonal component was demonstrated and Bortezomib and Dexamethasone (BD) was provided as initial therapy. After seven courses of therapy, renal function improved without dialysis requirements up to a GFR 31 mL/min. Under hematological complete response (HCR) the patient underwent high dose of melphalan (HDM) and autologous peripheral blood stem cell transplant. Fifty-four months later the patient remains in HCR and the GFR has progressively improved up to 48 mL/min. This report describes a notably renal function improvement in a patient with Light Chain Deposition Disease after therapy with BD followed by HDM, which can support this treatment as a future option for these patients.

Ig-related renal disease in lymphoplasmacytic disorders: an update

Ig-related renal diseases occurring in lymphoplasmacytic disorders (LPD) cover a wide spectrum of renal lesions. Except for cast nephropathy, which is almost specific for multiple myeloma, similar renal lesions caused by deposition or precipitation of monoclonal Ig-related material may occur in the various types of LPD. Because the secreted Ig provides the link between the LPD and the kidney disease, the renal outcome is linked to efficacy of chemotherapy. In the past 10 years, considerable advances have occurred in chemotherapy regimens with the advent of new classes of drugs, which already result in markedly improved renal and vital survival.

Renal failure caused by plasma cell infiltration in multiple myeloma

We report on a case of severe renal failure in a 61-year-old female with multiple myeloma (MM). Two months prior to admission, the patient was diagnosed to have anemia and progressive renal failure associated with urinary Bence Jones protein and was referred to our hospital. A bone marrow biopsy revealed 40% plasma cells with κ light chain restriction. Thus, she was considered to have MM. A renal biopsy revealed neoplastic plasma cell infiltration within the kidney, moderate interstitial fibrosis, tubular atrophy, and punctate, electron-dense material along the peripheral capillary walls, tubular basement membrane, and in the interstitium of the kidney. This suggested that a combination of compression of the tubules and the microvasculature by the infiltrative process, and local light chain deposition-mediated tissue damage might be implicated in the development of renal failure in this patient. Despite a remission of bone marrow plasmacytosis with a bortezomib-based regimen, her renal function gradually deteriorated and a periodic hemodialysis program was finally required. Although the clinical impact of the direct kidney infiltration of neoplastic plasma cells on the longitudinal changes in renal function remains to be delineated, it is reasonable to consider that the infiltration of neoplastic plasma cells associated with local light chain depositions may result in irreversible renal injuries. Obviously, further studies and accumulation of additional experience with renal biopsy are required to better determine the precise and prognostic relationship between renal outcome and morphological alterations among MM patients with varying degrees of renal impairment.

Acute cerebral infarction in a patient with nodular glomerulopathy--atypical features and differential diagnosis

Nodular glomerulopathy is a pattern of glomerular injury observed under light microscopy that could result from several diseases presented as nephrotic syndrome clinically. Compared with venous thrombosis, cerebral infarction resulting from arterial thrombosis is relatively rare in these patients. We report an interesting case of severe nephrotic syndrome complicated with acute cerebral infarction, and renal biopsy revealed nodular glomerulopathy under light microscopy. Immunofluorescent staining was positive for λ light chain (predominant) and κ light chain, mainly in mesangial areas, and electron microscopic study showed massive amorphous acellular deposits also in mesangial areas with some local extension to subendothelial space. Congo red stain gave negative results under polarized light. The case was concluded as an atypical presentation of light chain deposition disease both pathologically and clinically.

State-of-the-Art Management of Complications of Myeloma and Its Treatment

Multiple myeloma is an incurable disease, although patient survival has increased with the availability of novel agents. Both multiple myeloma and its therapies often affect the renal, immune, skeletal, hematologic, and nervous systems. The resulting organ dysfunctions often impair the quality of life of affected patients, complicate and limit subsequent therapies, and may result in significant mortality. Research on the treatment of complications of multiple myeloma has been limited; hence, preventative and management strategies for patients with these complications are heterogeneous and often based on anecdotal experience. In this paper, we review the effects of myeloma and the novel therapies on organ systems and suggest management strategies.

[Kidney involvement in hematologic malignancies. Diagnostic approach]

Kidney involvement is frequent in hematologic malignancies. It is associated with adverse outcome and treatment difficulties. It can affect every area of the renal parenchyma (tubules, interstitium, glomerulus, vessels). Various mechanisms could be implicated: deposits of immunoglobulin fractions or crystals, renal infiltration by malignant cells, urinary tract obstruction, paraneoplastic or storage glomerulopathies… Diagnostic strategy relies on the clinical presentation: acute renal failure, chronic kidney disease, glomerular proteinuria with or without nephrotic syndrome, tubular proteinuria, hydroelectrolytic disorders. In this review, we detail the diagnostic tests that are needed for the detection and the follow-up of renal involvement in hematologic malignancies, and clarify the indications of renal biopsy. We propose diagnostic strategies of renal involvement in myeloma, Waldenström's disease, high grade lymphomas and acute leukemias, low grade lymphomas and chronic leukemias. The adverse effects of treatments (chemotherapy, radiotherapy, stem cell graft …) are not addressed in this review.

Kidney disease associated with plasma cell dyscrasias

Plasma cell dyscrasias are frequently encountered malignancies often associated with kidney disease through the production of monoclonal immunoglobulin (Ig). Paraproteins can cause a remarkably diverse set of pathologic patterns in the kidney and recent progress has been made in explaining the molecular mechanisms of paraprotein-mediated kidney injury. Other recent advances in the field include the introduction of an assay for free light chains and the use of novel antiplasma cell agents that can reverse renal failure in some cases. The role of stem cell transplantation, plasma exchange, and kidney transplantation in the management of patients with paraprotein-related kidney disease continues to evolve.

Bortezomib successfully reverses early recurrence of light-chain deposition disease in a renal allograft: a case report

Light-Chain Deposition Disease (LCDD) frequently recurs after renal transplantation, displaying a pernicious course. Herein we have described a 39-year-old Caucasian man with a history of immunoglobulin G-kappa multiple myeloma who failed two chemotherapy regimens, but ultimately responded to the combination of thalidomide, bortezomib, and dexamethasone followed by high-dose melphalan and autologous stem cell transplantation 3 years prior to transplantation, during which time he showed no evidence of persistent or recurrent disease. At 3 days following spousal living related renal transplantation, he displayed a rapid deterioration of renal function requiring dialysis therapy. This episode failed to respond to empiric antirejection therapy including anti-thymocyte globulin, plasmapheresis, and anti-CD20 monoclonal antibody. Increasing evidence suggested recurrence of LCDD, including positive immunofluorescence staining of basement membranes and vessels for kappa light chains as well as free kappa light chains in his urine and serum. Following suspension of sirolimus, he was initiated on and responded to bortezomib (1.3 mg/m(2)) with discontinuation of dialysis within 3 weeks and progressively improving renal function. His maintenance therapy, in addition to six 2-week-long cycles of bortezomib separated by 1-week rest periods, includes cyclosporine (50 mg twice daily), prednisone (10 mg daily), and curcumin (9 g daily). In sum, bortezomib rescue therapy salvaged a spousal renal transplant afflicted with recurrent LCDD.

Biopsy-proven resolution of renal light-chain deposition disease after autologous stem cell transplantation

Light-chain deposition disease (LCDD) is caused by an underlying clonal plasma cell dyscrasia in which monoclonal immunoglobulin light chains (LCs) are deposited in tissues, resulting in varying degrees of organ dysfunction. Autologous stem cell transplantation (ASCT) has been reported to stabilize renal function in patients with LCDD, but currently, no evidence of histopathologic resolution of LC deposition after ASCT exists. We present a patient, with severe renal dysfunction due to LCDD, who was treated with high-dose melphalan and ASCT that resulted in a significant and extended period of improved renal function. Four years after the initial improvement, the patient developed nephrotic range proteinuria, without any evidence of relapse of the plasma cell dyscrasia. At that time, a repeat renal biopsy showed complete resolution of LC depositions and development of extensive glomerulosclerosis, thus explaining proteinuria. To the best of our knowledge, this is the first report of a biopsy-proven resolution of renal LCDD following ASCT. A timely application of ASCT should be considered in LCDD to prevent deterioration of renal function in the long run.

Extraosseus plasmacytoma of the pharynx with localized light chain deposition. Case report

Light chain deposition disease (LCDD) is a rare disorder associated with a clonal proliferation of plasma cells, which synthesize abnormal monoclonal immunoglobulin light chains. It is characterized by systemic deposition of light chains in various organs, with the kidneys being most commonly affected. There have been few reports of isolated LCDD, i.e. in the brain, lungs and cervical lymph nodes. We here report on another patient with an isolated form of LCDD, which was limited to the pharyngeal mucosa and was associated with an extraosseus plasmacytoma of the pharynx, expanding the spectrum that has been recognized for LCDD. The patient was treated by local radiotherapy, with an excellent response. A less aggressive clinical course can probably be expected than in the usual form of LCDD, but a long-term follow-up is necessary to establish the clinical significance of this variant of LCDD.

Light chain deposition disease developing 15 years following the diagnosis of monoclonal gammopathy of undetermined significance

A 64-year-old woman was admitted because of leg edema. Fifteen years previously she had been diagnosed with monoclonal gammopathy of undetermined significance (MGUS). Urinary immunoelectrophoresis demonstrated positivity for IgA kappa light chains. Bone marrow aspiration revealed a mild plasmacytosis. Her renal biopsy specimen revealed thickened basement membrane, mesangial cell proliferation and an increase in the mesangial matrix. Immunofluorescence studies showed the deposition of kappa light chains in the capillary wall and nodular lesions. These findings confirmed a diagnosis of light chain deposit disease (LCDD) with MGUS. The development of LCDD in patients with MGUS for fifteen years is very rare.