Managing light chain deposition disease

Dyspnea and cough in a 68-year-old female with light chain deposition disease

Light chain deposition disease (LCDD) is a rare hematologic disorder characterized by non-amyloid monoclonal immunoglobulin light chain deposition in multiple organs. Pulmonary LCDD (PLCDD) is an uncommon manifestation of LCDD usually seen in middle-aged patients presenting with radiologic cystic and nodular findings. We report the case of a 68-year-old female who presented with shortness of breath and atypical chest pain. Chest computerized tomography (CT) scan revealed numerous diffuse but basilar predominant pulmonary cysts and mild bronchiectasis without nodular disease. Given concomitant abnormal renal function and hepatic laboratory indices, she underwent biopsy of both organs confirming the presence of LCDD. Directed chemotherapy was initiated and stabilized renal and hepatic progression, but on follow-up imaging, pulmonary disease appeared worse. While therapeutic options targeting other organ involvement are available, their directed efficacy for progressive lung disease is not well known.

Free light chains injure proximal tubule cells through the STAT1/HMGB1/TLR axis

Free light chains (FLCs) induce inflammatory pathways in proximal tubule cells (PTCs). The role of TLRs in these responses is unknown. Here we present findings on the role of TLRs in FLC-induced PTC injury. We exposed human kidney PTC cultures to κ and λ FLCs and used cell supernatants and pellets for ELISA and gene expression studies. We also analyzed tissues from Stat1-/- and littermate control mice treated with daily i.p. injections of a κ FLC for 10 days. FLCs increased the expression of TLR2, TLR4, and TLR6 via HMGB1, a damage-associated molecular pattern. Countering TLR2, TLR4, and TLR6 through GIT-27 or specific TLR siRNAs reduced downstream cytokine responses. Blocking HMGB1 through siRNA or pharmacologic inhibition, or via STAT1 inhibition, reduced FLC-induced TLR2, TLR4, and TLR6 expression. Blocking endocytosis of FLCs through silencing of megalin/cubilin, with bafilomycin A1 or hypertonic sucrose, attenuated FLC-induced cytokine responses in PTCs. IHC showed decreased TLR4 and TLR6 expression in kidney sections from Stat1-/- mice compared with their littermate controls. PTCs exposed to FLCs released HMGB1, which induced expression of TLR2, TLR4, and TLR6 and downstream inflammation. Blocking FLCs' endocytosis, Stat1 knockdown, HMGB1 inhibition, and TLR knockdown each rescued PTCs from FLC-induced injury.

Bortezomib-Based Chemotherapy with Autologous Stem Cell Transplantation for Monoclonal Gammopathy of Renal Significance: A Case Report and Literature Review

BACKGROUND/AIMS

The term monoclonal gammopathy of renal significance (MGRS) was introduced in 2012 to emphasize kidney lesions in monoclonal gammopathy patients. Bortezomib-based chemotherapy has become the first-line treatment for MGRS.

OBJECTIVES

The objective of this study was to investigate whether the strategy of combining chemotherapy with autologous stem cell transplantation (ASCT) could improve prognosis and decrease functional kidney impairment in patients with MGRS.

METHODS

We reported the case of a 44-year-old Asian patient who was diagnosed with MGRS and received 5 cycles of Velcade® (a trade name for bortezomib), thalidomide, and dexamethasone therapy (VTD therapy), and subsequently underwent ASCT. In addition, we performed a literature review and summarized the latest advances in the characterization, treatment, and prognosis of MGRS.

RESULTS

The patient was diagnosed with light chain deposition disease by renal biopsy. After 5 cycles of VTD therapy, the patient had a very good partial response characterized by the resolution of M-protein (20.2% before treatment vs. 2.5% after treatment), remission of the level of serum free lambda (FLAM; over 80% decline), and normalization of the serum free light chain (sFLC) ratio (κ to λ). He also had a renal response characterized by a decreased serum creatinine level (1.61 vs.1.34 mg/dL) and less severe proteinuria (6.77 g/24 h vs.1.264 g/24 h) after chemotherapy. Importantly, after ASCT, the patient achieved a complete response (CR) characterized by a negative serum immunofixation electrophoresis (IFE) result and a dramatic decrement in FLAM (over 90%). Furthermore, 6 months after ASCT, the patient still remained in stable condition with a negative IFE result, normal sFLC ratio, and low level of serum creatinine (1.31 mg/dL) and proteinuria (0.339 g/24 h). In our retrospective literature analysis, we found that MGRS patient survival time and renal outcome had been markedly improved by current therapies due to the popularization of bortezomib-based chemotherapy and ASCT.

CONCLUSIONS

The patient successfully achieved CR after VTD therapy followed by ASCT. However, this treatment is controversial, and a standard therapy recommendation for MGRS has not been established. Bortezomib-based chemotherapy combined with ASCT may have prospects for the treatment of MGRS, but the exact effects of ASCT remain unclear and should be thoroughly investigated.

Clinical characteristics and prognostic factors in multiple myeloma patients with light chain deposition disease

Light chain deposition disease (LCDD) is characterized by monotypic immunoglobulin depositions which will eventually lead to loss of organ function if left untreated. While the kidney is almost always affected, the presence and degree of LCDD in other organs vary. Ten to thirty percent of LCDD patients have underlying Multiple Myeloma (MM), yet outcome and prognostic markers in this particular patient group are still lacking. Here, we analyzed 69 patients with MM and biopsy proven LCDD and report on renal and extra-renal involvement and its impact on prognosis as well as renal response depending on hematologic response. Coexisting light chain diseases such as AL amyloid and cast nephropathy were found in 30% of patients; those with LCDD and concurrent amyloid tended to have shorter survival. Cardiac involvement by LCDD was seen in one-third of our patients and was associated with shorter overall survival; such patients also had a significantly higher risk of treatment-related mortality (TRM) after stem cell transplant (SCT) compared to LCDD patients without cardiac involvement. This study highlights that MM patients with LCDD present with different clinical features compared to previously reported LCDD cohorts. Rapid initiation of treatment is necessary to prevent progressive renal disease and worse outcome. Coexisting light chain diseases and cardiac involvement are more common than previously reported and confer worse clinical outcome, emphasizing the need for careful patient careful patient evaluation and treatment selection.

[Light-chain deposition disease is a hematologic problem]

AIM

To analyze clinical and laboratory data and treatment results in patients with light-chain deposition disease (LCDD).

SUBJECTS AND METHODS

Nine patients with LCDD and kidney injury were examined. The diagnosis was based on the results of light and immunofluorescence microscopy of renal biopsy specimens. All the patients received bortezomib, cyclophosphamide, and dexamethasone (VCD) induction therapy.

RESULTS

Six patients were diagnosed with multiple myeloma; in 3 patients LCDD was considered within monoclonal gammopathy manly involving the kidney. By the initiation of therapy, all the patients were diagnosed as having chronic kidney disease (Stage III (n=2), Stage IV (n=2), and dialysis-related renal failure (n=5)). After the VCD treatment, 7 of 9 patients achieved a hematologic response. Second-line therapy with lenalidomide proved to be effective in the other 2 cases. Five patients achieved complete remission; 3 had a very good partial remission. Thereafter, 2 patients received high-dose melphalan chemotherapy and autologous hematopoietic stem cell transplantation. Better renal function was noted in only 2 cases.

CONCLUSION

Despite the high efficiency of therapy aimed to reduce monoclonal light chains; improved renal function was observed in only 2 (22%) patients. Such low rates of a renal response were due to the late initiation of therapy.

[Secondary monoclonal gammopathy after bone marrow autotransplantation as a cause of worse renal function in light chain immunoglobulin deposition disease]

The paper describes a clinical case of a female woman with nephropathy due to light chain deposition disease caused by secretion of κ Bence-Jones protein. Complete immunochemical remission was achieved after induction therapy using a bortezomib + cyclophosphamide + dexamethasone regimen. Renal function remained unchanged (glomerular filtration rate 16 ml/min), there was a reduction in proteinuria from 5.8 to 2.6 g/day. High-dose melphalan (200 mg/m2) chemotherapy with peripheral blood stem cell autotransplantation was performed as consolidation of remission. A year posttransplantation, there was no secretion of κ light chains; however, monoclonal IgG lambda emerged in a quantity of 3.2 g/l. At the same period, nephrotic syndrome became progressive (daily proteinuria 12 g) and dialysis-dependent renal failure developed. A repeat renal biopsy specimen revealed changes, suggesting that there was a decrease in renal deposits of κ light chains. Simultaneously with this, the obvious negative trend as progressive nephrosclerosis and fixation of IgG and λ light chains in the glomeruli (in the sclerotic areas) cause IgGλ monoclonal protein to be involved in the genesis of further kidney injury. Attention is also paid to different characteristics of capillary wall deposits by density (according to the electron microscopic findings), which may point to their different qualitative composition and possibly different formation duration. Papaprotein Gλ disappeared after a year without therapy, suggesting its reactivity. The findings confirm that worse renal function is caused by the action of paraprotein Gλ due to secondary (after autologous hematopoietic stem cells transplantation) monoclonal gammopathy.