Kidney diseases associated with monoclonal immunoglobulin M-secreting B-cell lymphoproliferative disorders: a case series of 35 patients

BACKGROUND

Kidney diseases associated with immunoglobulin M (IgM) monoclonal gammopathy are poorly described, with few data for patient outcomes and renal response.

STUDY DESIGN

Case series.

SETTING & PARTICIPANTS

35 patients from 8 French departments of nephrology were retrospectively studied. Inclusion criteria were: (1) detectable serum monoclonal IgM, (2) estimated glomerular filtration rate (eGFR) < 60mL/min/1.73m(2) and/or proteinuria with protein excretion > 0.5g/d and/or microscopic hematuria, and (3) kidney biopsy showing monoclonal immunoglobulin deposits and/or lymphomatous B-cell renal infiltration. All patients received chemotherapy, including rituximab-based regimens in 8 cases.

PREDICTORS

Patients were classified into 3 groups according to renal pathology: glomerular AL amyloidosis (group 1; n=11), nonamyloid glomerulopathies (group 2; n=15, including 9 patients with membranoproliferative glomerulonephritis), and tubulointerstitial nephropathies (group 3; n=9, including cast nephropathy in 5, light-chain Fanconi syndrome in 3, and isolated tumor infiltration in 1).

OUTCOMES

Posttreatment hematologic response (≥50% reduction in serum monoclonal IgM and/or free light chain level) and renal response (≥50% reduction in 24-hour proteinuria or eGFR≥30mL/min/1.73m(2) in patients with glomerular and tubulointerstitial disorders, respectively).

RESULTS

Nephrotic syndrome was observed in 11 and 6 patients in groups 1 and 2, respectively. Patients in group 3 presented with acute kidney injury (n=7) and/or proximal tubular dysfunction (n=3). Waldenström macroglobulinemia was present in 26 patients (8, 12, and 6 in groups 1, 2, and 3, respectively). Significant lymphomatous interstitial infiltration was observed in 18 patients (4, 9, and 5 patients, respectively). Only 9 of 29 evaluable patients had systemic signs of symptomatic hematologic disease (2, 5, and 2, respectively). In groups 1, 2, and 3, respectively, hematologic response was achieved after first-line treatment in 3 of 9, 9 of 10, and 5 of 6 evaluable patients, while renal response occurred in 5 of 10, 9 of 15, and 5 of 8 evaluable patients.

LIMITATIONS

Retrospective study; insufficient population to establish the impact of chemotherapy.

CONCLUSIONS

IgM monoclonal gammopathy is associated with a wide spectrum of renal manifestations, with an under-recognized frequency of tubulointerstitial disorders.

Clinico-biological characteristics and treatment of type I monoclonal cryoglobulinaemia: a study of 64 cases

This retrospective analysis was conducted in 64 patients diagnosed with type I cryoglobulinaemia (CG) followed at two French centres. Median follow-up was 6·75 years. CG was IgG in 60% and IgM in 40% of all cases and was asymptomatic in 16 patients (25%). Cold-triggered ischaemic skin manifestations were observed in 33 patients (51%). Neurological manifestations were observed in 15 patients and renal manifestations in 13. Most of the patients with necrotic purpura (14/16, P = 0·009) and renal manifestations (11/13, P = 0·057) had IgG CG. IgG CG was associated with monoclonal gammopathy of undetermined significance (MGUS), myeloma, chronic lymphocytic leukaemia and lymphoplasmocytic lymphoma in 18, 13, 5 and 2 patients, respectively. IgM CG was associated with MGUS and Waldenström macroglobulinaemia in 8 and 18 cases, respectively. One third of patients did not receive any specific treatment. Various treatments, including rituximab, were administered to 25/31 patients with IgG CG and 6/25 patients with IgM CG due to CG-related symptoms. Rituximab was ineffective in all cases associated with a predominantly plasmacytic proliferation. To conclude, type I CG has specific clinico-biological characteristics compared to type II CG. Furthermore, there are differences in terms of related manifestations between type I IgG and type I IgM CG.

Long-term follow-up from a phase 1/2 study of single-agent bortezomib in relapsed systemic AL amyloidosis

CAN2007 was a phase 1/2 study of once- and twice-weekly single-agent bortezomib in relapsed primary systemic amyloid light chain amyloidosis (AL) amyloidosis. Seventy patients were treated, including 18 and 34 patients at the maximum planned doses on the once- and twice-weekly schedules. This prespecified final analysis provides mature response and long-term outcomes data after 3-year additional follow-up since the last report. In the once-weekly 1.6 mg/m(2) and twice-weekly 1.3 mg/m(2) bortezomib groups, final hematologic response rates were 68.8% and 66.7%; 80% of patients in each group sustained their response for ≥1 year. One-year progression-free rates were 72.2% and 76.8%. Median overall survival (OS) was 62.1 months and not reached; 4-year OS rates were 75.0% and 63.0%. Low baseline difference in κ/λ free light-chain level was associated with higher hematologic complete response rates and longer OS. At data cutoff, 40 (57%) patients had received subsequent therapy, including 19 (27%) retreated with bortezomib, 11 (58%) of whom achieved complete or partial hematologic responses. Four patients received prolonged bortezomib for between 3.5 and 5.6 years, with no new safety concerns, highlighting the feasibility of long-term therapy. Single-agent bortezomib produced durable hematologic responses and promising long-term OS in relapsed AL amyloidosis. This trial was registered at www.clinicaltrials.gov as #NCT00298766.

Lenalidomide and dexamethasone in transplant-ineligible patients with myeloma

BACKGROUND

The combination melphalan-prednisone-thalidomide (MPT) is considered a standard therapy for patients with myeloma who are ineligible for stem-cell transplantation. However, emerging data on the use of lenalidomide and low-dose dexamethasone warrant a prospective comparison of the two approaches.

METHODS

We randomly assigned 1623 patients to lenalidomide and dexamethasone in 28-day cycles until disease progression (535 patients), to the same combination for 72 weeks (18 cycles; 541 patients), or to MPT for 72 weeks (547 patients). The primary end point was progression-free survival with continuous lenalidomide-dexamethasone versus MPT.

RESULTS

The median progression-free survival was 25.5 months with continuous lenalidomide-dexamethasone, 20.7 months with 18 cycles of lenalidomide-dexamethasone, and 21.2 months with MPT (hazard ratio for the risk of progression or death, 0.72 for continuous lenalidomide-dexamethasone vs. MPT and 0.70 for continuous lenalidomide-dexamethasone vs. 18 cycles of lenalidomide-dexamethasone; P<0.001 for both comparisons). Continuous lenalidomide-dexamethasone was superior to MPT for all secondary efficacy end points, including overall survival (at the interim analysis). Overall survival at 4 years was 59% with continuous lenalidomide-dexamethasone, 56% with 18 cycles of lenalidomide-dexamethasone, and 51% with MPT. Grade 3 or 4 adverse events were somewhat less frequent with continuous lenalidomide-dexamethasone than with MPT (70% vs. 78%). As compared with MPT, continuous lenalidomide-dexamethasone was associated with fewer hematologic and neurologic toxic events, a moderate increase in infections, and fewer second primary hematologic cancers.

CONCLUSIONS

As compared with MPT, continuous lenalidomide-dexamethasone given until disease progression was associated with a significant improvement in progression-free survival, with an overall survival benefit at the interim analysis, among patients with newly diagnosed multiple myeloma who were ineligible for stem-cell transplantation. (Funded by Intergroupe, Francophone du Myélome and Celgene; FIRST ClinicalTrials.gov number, NCT00689936; European Union Drug Regulating Authorities Clinical Trials number, 2007-004823-39.).

Results after long-term follow-up from the CAN2007 phase I/II study of weekly or twice-weekly bortezomib in patients (pts) with relapsed systemic light-chain (AL) amyloidosis

8545

Background: Data from multiple studies suggest that bortezomib alone or in combination regimens is active in newly diagnosed and relapsed AL. CAN2007 (NCT00298766) was the first prospective study of single-agent bortezomib in relapsed AL. Here we report outcome data at study closure after a median follow-up of 51.8 mos (median 46.1–66.1 mos). Methods: 70 pts received bortezomib 0.7, 1.0, 1.3, or 1.6 mg/m2 on days 1, 8, 15, and 22 of 35-day cycles (QW) or 0.7, 1.0, or 1.3 mg/m2 on days 1, 4, 8, and 11 of 21-day cycles (BIW) for up to 8 cycles (or longer in pts with evidence of ongoing clinical benefit). The maximum tolerated dose was not reached on either schedule; 18 and 34 pts were treated at the maximum planned doses of 1.6 mg/m2 QW and 1.3 mg/m2BIW, respectively, and 18 pts were treated at lower doses. Post-treatment, pts were followed every 6 weeks until disease progression, and then every 3 mos for survival during the long-term follow-up phase. Results: Pts received a median (range) of 8 (1–39), 6 (1–57), and 8 (3–57) cycles of bortezomib in the 1.6 mg/m2 QW, 1.3 mg/m2 BIW, and lower-dose groups, respectively; overall, 32 (46%) pts received ≥8 cycles, and 4 pts were still on treatment and had received ≥39 cycles at study closure. Hematologic responses and outcomes are summarized below. Median (range) follow-up for survival was 51.8 (1–68), 46.1 (1–61), and 66.1 (2–80) mos, and 7, 12, and 9 pts have died, in the 1.6 mg/m2 QW, 1.3 mg/m2BIW, and lower-dose groups, respectively. Median overall survival (OS) in all 70 pts was 62.7 mos, and 4-yr OS rate was 67.3%; data by dose group are shown below. Conclusions: Single-agent bortezomib produces durable hematologic responses and promising long-term OS data in pts with relapsed AL. Clinical trial information: NCT00298766. [Table: see text]

Optimizing treatment strategies in myeloma cast nephropathy: rationale for a randomized prospective trial

Renal failure is a frequent complication of multiple myeloma (MM) that strongly affects patient survival. Although a variety of renal diseases may be observed in MM, myeloma cast nephropathy (MCN), a tubulo-interstitial disorder related to precipitation of a monoclonal light chain (LC) within tubular distal lumens, is the main cause of severe and persistent renal failure. To date, the respective frequency and initial evolution of renal disorders associated with monoclonal LC in MM remain poorly defined. Treatment of MCN relies on urgent symptomatic measures and rapid introduction of chemotherapy to reduce the production of monoclonal LC. The introduction of novel chemotherapy regimens based on the association of bortezomib with dexamethasone is likely to have improved the prognosis of MM patients with renal failure. In addition, the combination of novel agents with efficient removal of circulating LC through high cut-off hemodialysis membrane may further increase renal response rate. However, the impact on patient and renal outcomes of these potential therapeutic advances has not been evaluated in prospective studies. The randomized trials EuLITE in the UK and Germany and MYRE in France should help to answer these issues. MYRE is a randomized controlled phase III trial (NCT01208818) that aims to better define the epidemiology and typology of inaugural renal failure in MM and to optimize therapy of MCN patients with and without dialysis-dependent renal failure.

Al amyloidosis

Definition of the disease

AL amyloidosis results from extra-cellular deposition of fibril-forming monoclonal immunoglobulin (Ig) light chains (LC) (most commonly of lambda isotype) usually secreted by a small plasma cell clone. Most patients have evidence of isolated monoclonal gammopathy or smoldering myeloma, and the occurrence of AL amyloidosis in patients with symptomatic multiple myeloma or other B-cell lymphoproliferative disorders is unusual. The key event in the development of AL amyloidosis is the change in the secondary or tertiary structure of an abnormal monoclonal LC, which results in instable conformation. This conformational change is responsible for abnormal folding of the LC, rich in β leaves, which assemble into monomers that stack together to form amyloid fibrils.

Epidemiology

AL amyloidosis is the most common type of systemic amyloidois in developed countries with an estimated incidence of 9 cases/million inhabitant/year. The average age of diagnosed patients is 65 years and less than 10% of patients are under 50.

Clinical description

The clinical presentation is protean, because of the wide number of tissues or organs that may be affected. The most common presenting symptoms are asthenia and dyspnoea, which are poorly specific and may account for delayed diagnosis. Renal manifestations are the most frequent, affecting two thirds of patients at presentation. They are characterized by heavy proteinuria, with nephrotic syndrome and impaired renal function in half of the patients. Heart involvement, which is present at diagnosis in more than 50% of patients, leading to restrictive cardiopathy, is the most serious complication and engages prognosis.

Diagnostic methods

The diagnosis relies on pathological examination of an involved site showing Congo red-positive amyloid deposits, with typical apple-green birefringence under polarized light, that stain positive with an anti-LC antibody by immunohistochemistry and/or immunofluorescence. Due to the systemic nature of the disease, non-invasive biopsies such as abdominal fat aspiration should be considered before taking biopsies from involved organs, in order to reduce the risk of bleeding complications.

Differential diagnosis

Systemic AL amyloidosis should be distinguished from other diseases related to deposition of monoclonal LC, and from other forms of systemic amyloidosis. When pathological studies have failed to identify the nature of amyloid deposits, genetic studies should be performed to diagnose hereditary amyloidosis.

Management

Treatment of AL amyloidosis is based on chemotherapy, aimed at controlling the underlying plasma clone that produces amyloidogenic LC. The hematological response should be carefully checked by serial measurements of serum free LC. The association of an alkylating agent with high-dose dexamethasone has proven to be effective in two thirds of patients and is considered as the current reference treatment. New agents used in the treatment of multiple myeloma are under investigation and appear to increase hematological response rates. Symptomatic measures and supportive care is necessary in patients with organ failure. Noticeably, usual treatments for cardiac failure (i.e. calcium inhibitors, β-blockers, angiotensin converting enzyme inhibitors) are inefficient or even dangerous in patients with amyloid heart disease, that should be managed using diuretics. Amiodarone and pace maker implantation should be considered in patients with rhythm or conduction abnormalities. In selected cases, heart and kidney transplantation may be associated with prolonged patient and graft survival.

Prognosis

Survival in AL amyloidosis depends on the spectrum of organ involvement (amyloid heart disease being the main prognosis factor), the severity of individual organs involved and haematological response to treatment.

Estimating the treatment effect from non-randomized studies: The example of reduced intensity conditioning allogeneic stem cell transplantation in hematological diseases

Background

In some clinical situations, for which RCT are rare or impossible, the majority of the evidence comes from observational studies, but standard estimations could be biased because they ignore covariates that confound treatment decisions and outcomes.

Methods

Three observational studies were conducted to assess the benefit of Allo-SCT in hematological malignancies of multiple myeloma, follicular lymphoma and Hodgkin’s disease. Two statistical analyses were performed: the propensity score (PS) matching approach and the inverse probability weighting (IPW) approach.

Results

Based on PS-matched samples, a survival benefit in MM patients treated by Allo-SCT, as compared to similar non-allo treated patients, was observed with an HR of death at 0.35 (95%CI: 0.14-0.88). Similar results were observed in HD, 0.23 (0.07-0.80) but not in FL, 1.28 (0.43-3.77). Estimated benefits of Allo-SCT for the original population using IPW were erased in HR for death at 0.72 (0.37-1.39) for MM patients, 0.60 (0.19-1.89) for HD patients, and 2.02 (0.88-4.66) for FL patients.

Conclusion

Differences in estimated benefits rely on whether the underlying population to which they apply is an ideal randomized experimental population (PS) or the original population (IPW). These useful methods should be employed when assessing the effects of innovative treatment in non-randomized experiments.

Novel approaches for reducing free light chains in patients with myeloma kidney

Myeloma kidney is a tubulointerstitial pathology that accounts for approximately 80-90% of severe acute kidney injury in patients with multiple myeloma. Unless there is rapid intervention, progressive irreversible damage from interstitial fibrosis and tubular atrophy occurs. Work over the past decade has demonstrated that an early sustained reduction in serum concentrations of pathogenic monoclonal free light chains (FLCs) leads to improved renal recovery rates. In turn, an early improvement in renal function is associated with improved patient survival. An early reduction in FLC levels should therefore become standard of care, although the optimum mechanisms to achieve this depletion of FLCs remain to be determined. To provide a coordinated, cross-disciplinary approach to research in this disease, the International Kidney and Monoclonal Gammopathy Research Group was formed. In this Review, we address the current state of knowledge in the management of myeloma kidney.

The human immunodeficiency virus-1 protease inhibitor nelfinavir impairs proteasome activity and inhibits the proliferation of multiple myeloma cells in vitro and in vivo

BACKGROUND

Multiple myeloma is characterized by the accumulation of tumor plasma cells in the bone marrow. Despite therapeutic improvements brought by proteasome inhibitors such as bortezomib, myeloma remains an incurable disease. In a variety of human cancers, human immunodeficiency virus protease inhibitors (e.g. nelfinavir) effectively inhibit tumor progression, but their impact on myeloma is unknown. We assessed the in vitro and in vivo effects of nelfinavir on multiple myeloma.

DESIGN AND METHODS

The effects of nelfinavir (1-10 μM) on proteasome activity, proliferation and viability of myeloma cell lines and plasma cells from patients were assessed by measuring PERK, AKT, STAT3 and ERK1/2 phosphorylation and CHOP expression with immunoblotting or flow cytometry. The in vivo effect was assessed in NOD/SCID mice injected with luciferase expressing human myeloma cell lines and treated with nelfinavir at a dose of 75 mg/kg/day. Tumor progression was evaluated using a bioluminescent system.

RESULTS

Nelfinavir inhibited 26S chymotrypsin-like proteasome activity, impaired proliferation and triggered apoptosis of the myeloma cell lines and fresh plasma cells. It activated the pro-apoptotic unfolded protein response pathway by inducing PERK phosphorylation and CHOP expression. Cell death triggered by nelfinavir treatment correlated with decreased phosphorylation of AKT, STAT3 and ERK1/2. Nelfinavir enhanced the anti-proliferative activity of bortezomib, dexamethasone and histone deacetylase inhibitors and delayed tumor growth in a myeloma mouse model.

CONCLUSIONS

These results suggest that nelfinavir, used at a pharmacological dosage, alone or in combination, may be useful in the treatment of myeloma. Our data provide a preclinical basis for clinical trials using nelfinavir in patients with myeloma.

Impact of genetic abnormalities after allogeneic stem cell transplantation in multiple myeloma: a report of the Société Française de Greffe de Moelle et de Thérapie Cellulaire

BACKGROUND

The impact of cytogenetic abnormalities in multiple myeloma after allogeneic stem cell transplantation has not been clearly defined. This study examines whether allogeneic stem cell transplantation could be of benefit for myeloma patients with high-risk cytogenetic abnormalities.

DESIGN AND METHODS

This is a retrospective multicenter analysis of the registry of the Société Française de Greffe de Moelle et de Thérapie Cellulaire, including 143 myeloma patients transplanted between 1999 and 2008.

RESULTS

The incidences of cytogenetic abnormalities were 59% for del(13q), 25% for t(4;14), 25% for del(17p) and 4% for t(14;16). When comparing the population carrying an abnormality to that without the same abnormality, no significant difference was found in progression-free survival, overall survival or progression rate. Patients were grouped according to the presence of any of the poor prognosis cytogenetic abnormalities t(4;14), del(17p) or t(14;16) (n=53) or their absence (n=32). No difference in outcomes was observed between these two groups: the 3-year progression-free survival, overall survival and progression rates were 30% versus 17% (P=0.9), 45% versus 39% (P=0.8) and 53% versus 75% (P=0.9), respectively.

CONCLUSIONS

These data indicate that allogeneic stem cell transplantation could potentially be of benefit to high-risk myeloma patients.

Management of relapsed or refractory multiple myeloma in French hospitals and estimation of associated direct costs: a multi-centre retrospective cohort study

WHAT IS KNOWN AND BACKGROUND

 For relapsed or refractory multiple myeloma (RRMM), a series of novel agents (thalidomide, bortezomib and lenalidomide) has emerged during the latest decade, but their use in routine clinical practice is not well documented as well as the cost of RRMM.

OBJECTIVE

Our aim is to review the therapeutic management of such patients in France and to estimate the associated costs.

METHODS

A retrospective cohort study, based on chart reviews, was conducted in French Haematology Departments over the period 2004-2007 and the associated direct costs estimated.

RESULTS

One hundred and two patients with a relapse after first-line therapy were selected from five centres. The average follow-up from diagnosis or the date of first relapse to death or to the latest news was respectively 56.25 and 23.53 months. Novel agents were used in 73% of all cases, and in all cases of first relapse. Thalidomide and bortezomib were respectively the most frequently used second-line (57%) and third-line treatments (44%). The average number of lines of treatment received per patient as from first relapse was 2.75 (min 1; max 8) and the mean direct cost per month was estimated at 3130 € after the first relapse. This cost was represented in greater part by the cost of chemotherapy drugs (66%).

WHAT IS NEW AND CONCLUSION

The use of novel agents such as thalidomide, bortezomib and lenalidomide for RRMM is highly prevalent in France from the first relapse. The associated medical cost is substantial mainly due to the cost of the new agents.

[New insights in the treatment of myeloma with renal failure]

Renal failure, mostly related to myeloma cast nephropathy (MCN), is a frequent complication of multiple myeloma (MM), which occurs in up to 50% of patients during the course of the disease. Persistent renal failure in MM is associated with poor survival. Treatment of MCN relies on urgent symptomatic measures (alkalinisation, rehydration, correction of hypercalcemia, and withdrawal of nephrotoxic drugs), with rapid introduction of chemotherapy to efficiently reduce the production of monoclonal light chains (LC). Recent studies suggest that, in patients with MM and severe renal failure due to MCN, rapid removal of circulating LC, through intensive hemodialysis sessions using a new generation high cut-off dialysis membrane, might result in dialysis withdrawal in most patients. If the development of intensive therapy and new efficient chemotherapy agents (thalidomide, bortezomib, lenalidomide) has transformed the care and prognosis of MM, the modalities and safety of these therapeutic regimens in patients with renal failure remain to be defined. The association of bortezomib with dexamethasone should be considered currently as first-line treatment in patients with MM and impaired renal function.

[Current treatment of AL amyloidosis]

Systemic AL amyloidosis is a rare complication of monoclonal gammopathies. Renal manifestations are frequent, mostly characterized by heavy proteinuria, with nephrotic syndrome and renal failure in more than half of the patients at diagnosis. Without treatment, median survival does not exceed 12 months. Amyloid heart disease and diffusion of amyloid deposits are associated with reduced survival. Treatment of systemic AL amyloidosis has been profoundly modified with the introduction of international criteria for the definition of organ involvement and hematologic response, and with the use of sensitive tests for the measurement of serum-free light chain levels. Melphalan plus dexamethasone is now established as the gold standard for first line treatment of systemic AL, with similar efficacy and reduced treatment-related mortality compared to high-dose therapy. Modern chemotherapy regimens, based on the use of novel agents such as bortezomib and lenalidomide, might further improve patient survival.

Renal Impairment in Patients With Multiple Myeloma: A Consensus Statement on Behalf of the International Myeloma Working Group

Renal impairment is a common complication of multiple myeloma (MM). The estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease formula is the recommended method for the assessment of renal function in patients with MM with stabilized serum creatinine. In acute renal injury, the RIFLE (risk, injury, failure, loss and end-stage kidney disease) and Acute Renal Injury Network criteria seem to be appropriate to define the severity of renal impairment. Novel criteria based on eGFR measurements are recommended for the definition of the reversibility of renal impairment. Rapid intervention to reverse renal dysfunction is critical for the management of these patients, especially for those with light chain cast nephropathy. Bortezomib with high-dose dexamethasone is considered as the treatment of choice for such patients. There is limited experience with thalidomide in patients with myeloma with renal impairment. Thus, thalidomide can be carefully administered, mainly in the context of well-designed clinical trials, to evaluate if it can improve the rapidity and probability of response that is produced by the combination with bortezomib and high-dose dexamethasone. Lenalidomide is effective in this setting and can reverse renal insufficiency in a significant subset of patients, when it is given at reduced doses, according to renal function. The role of plasma exchange in patients with suspected light chain cast nephropathy and renal impairment is controversial. High-dose melphalan (140 mg/m2) and autologous stem-cell transplantation should be limited to younger patients with chemosensitive disease.

Galectin-1 and semaphorin-3A are two soluble factors conferring T-cell immunosuppression to bone marrow mesenchymal stem cell

In human physiology and animal models, bone marrow mesenchymal stem cells (MSCs) exert an immunosuppressive role in both in vitro and in vivo experiments. However, cellular and molecular mechanisms involved in this process are not clear and remain largely elusive. Several studies have suggested the implication of cell-cell contacts or soluble factors including transforming growth factor-b1 (TGF-b1), interleukin-10 (IL-10), indoleamine 2,3-dioxygenase (IDO), or human leukocyte antigen-G (HLA-G). Here, we show that both Galectin-1 and Semaphorin-3A (Sema-3A), 2 soluble factors capable to inhibit T-cell proliferation through neuropilin-1 (NP-1) binding, are highly expressed by MSCs and may account for their known suppressive activities. Furthermore, MSCs suppressive functions are completely reverted by soluble recombinant NP-1, the main receptor of both Galectin-1 and Sema-3A. Similar results were obtained by using blocking antibodies against Galectin-1 or Sema-3A. Taken together, these results demonstrate the critical role of Galectin-1 and Sema-3A in MSCs functions and may open new perspectives in the understanding and treatment of various immune and neoplastic disorders.

Late-onset combined immune deficiency: a subset of common variable immunodeficiency with severe T cell defect

BACKGROUND

Common variable immunodeficiency (CVID) is a primary immune deficiency defined by defective antibody production. In most series, a small proportion of patients present with opportunistic infections (OIs).

METHODS

The French DEFI study has enrolled patients with primary hypogammaglobulinemia and allows a detailed clinical and immunologic description of patients with previous OIs and/or at risk for OIs.

RESULTS

Among 313 patients with CVID, 28 patients (8.9%) presented with late-onset combined immune deficiency (LOCID), defined by the occurrence of an OI and/or a CD4(+) T cell count <200 x 10(6) cells/L, and were compared with the remaining 285 patients with CVID. The patients with LOCID more frequently belonged to consanguineous families (29% vs 8%; P = .004). They differed from patients with CVID with a higher prevalence of splenomegaly (64% vs 31%), granuloma (43% vs 10%), gastrointestinal disease (75% vs 42%), and lymphoma (29% vs 4%). Even on immunoglobulin substitution, they required more frequent antibiotics administration and hospitalization. Lymphocyte counts were lower, with a marked decrease in CD4(+) T cell counts (158 x 10(6) vs 604 x 10(6) cells/L; P < .001) and a severe defect in naive CD45RA(+)CCR7(+)CD4(+) T cell counts (<20% of total CD4(+) T cells in 71% of patients with LOCID vs 37% of patients with CVID; P = .001). The CD19(+) B cell compartment was also significantly decreased (20 x 10(6) vs 102 x 10(6) cells/L; P < .001).

CONCLUSIONS

LOCID differs from classic CVID in its clinical and immunologic characteristics. Systematic T cell phenotype may help to discriminate such patients from those with CVID. Identification of this phenotype should result in a more fitted diagnostic and therapeutic approach of infections and could provide insights for genetic diagnosis.

Clinical and morphologic spectrum of renal involvement in patients with mixed cryoglobulinemia without evidence of hepatitis C virus infection

Hepatitis C virus (HCV) infection represents, by far, the major cause of mixed cryoglobulinemia (MC). The renal disease associated with this pathological condition is now well described. By contrast, renal involvement in patients with MC not associated with HCV has been only poorly described, and few cases have been reported. We analyzed the demographic, clinical, and laboratory features and outcome in patients presenting with renal disease associated with MC not related to HCV infection. Records of 20 patients with MC and renal disease, with no evidence of HCV by serology and polymerase chain reaction analysis, were retrospectively analyzed. Renal biopsies and extensive searches for lymphoproliferative disorder were performed in all patients at presentation. MC was related to primary Sjögren Syndrome (pSS) in 9 patients, and to non-Hodgkin lymphoma in 1 patient, while MC was classified as essential in the remaining 10 cases. Renal involvement was characterized by microscopic hematuria in all patients, nephrotic range proteinuria in 75% of patients, hypertension in 80% of patients, and renal failure in 85% of patients (mean glomerular filtration rate, 46 mL/min per 1.73 m). Membranoproliferative glomerulonephritis with subendothelial deposits was observed in all kidney specimens. Skin vasculitis was the main extrarenal manifestation. In all patients, cryoglobulinemia was classified as type II MC, characterized by monoclonal IgMkappa and polyclonal IgG. Most patients (17/20) were treated with steroids or immunosuppressive agents, or both. Initial renal remission was observed in 94% of patients. However, renal relapse occurred in most patients, with 10% reaching end-stage renal disease. Three patients with essential MC developed B-cell lymphoma 36-48 months after the diagnosis of MC. Unexpectedly, B-cell lymphoma induced by Epstein-Barr virus infection occurred in only 1 of the 9 pSS patients. Forty percent of patients died as a result of extrarenal causes.Renal disease associated with MC unrelated to HCV is characterized by the high prevalence of pSS (45%), the finding of CD20+ B-lymphocyte nodular infiltrates in the kidney interstitium, and a high incidence of overt B-cell lymphoma during follow-up. These findings emphasize the need for repetitive clinical evaluation in those patients.

Update on Treatment Recommendations From the Fourth International Workshop on Waldenström's Macroglobulinemia

Waldenström macroglobulinemia (WM) is a distinct B-cell lymphoproliferative disorder characterized by lymphoplasmacytic bone marrow infiltration along with an immunoglobulin M (IgM) monoclonal gammopathy. Patients with disease-related cytopenias, bulky adenopathy or organomegaly, symptomatic hyperviscosity, severe neuropathy, amyloidosis, cryoglobulinemia, cold agglutinin disease, or evidence of disease transformation should be considered for immediate therapy. Initiation of therapy should not be based on serum IgM levels alone, and asymptomatic patients should be observed. Individual patient considerations should be considered when deciding on a first-line agent including the presence of cytopenias, need for rapid disease control, age, and candidacy for autologous transplantation. Therapeutic outcomes should be evaluated using updated criteria. As part of the Fourth International Workshop on Waldenström's Macroglobulinemia, a consensus panel updated its recommendations on both first-line and salvage therapy in view of recently published and ongoing clinical trials. The panel considered encouraging results from recent studies of first-line combinations such as rituximab with nucleoside analogs with or without alkylating agents or with cyclophosphamide-based therapies (eg, cyclophosphamide, doxorubicin, vincristine, and prednisone or cyclophosphamide and dexamethasone) or the combination of rituximab with thalidomide. Such therapeutic approaches are likely to yield responses at least as good as, if not better than, monotherapy with any of the alkylating agents, nucleoside analogs, or rituximab. In the salvage setting, reuse of a first-line regimen or use of a different regimen should be considered along with bortezomib, alemtuzumab, autologous transplantation, and, in selected circumstances, allogeneic transplantation. Finally, the panel reaffirmed its encouragement of the active enrollment of patients with WM onto innovative clinical trials whenever possible.

The clinical spectrum of IgM-related amyloidosis: a French nationwide retrospective study of 72 patients

Immunoglobulin M (IgM)-related amyloidosis remains a rare and little-known complication of monoclonal IgM-associated disorders. We sought to determine the clinical and laboratory presentation, response to treatment, and outcome of patients with IgM-related amyloidosis in the era of new therapeutic approaches. We conducted a retrospective study in 29 French centers to identify patients with monoclonal IgM and biopsy-proven amyloidosis; we reviewed patients' records and collected relevant clinical and laboratory data. We identified 72 patients with IgM-related amyloidosis. Systemic primary amyloidosis (AL) was present in 64, peritumoral AL in 5, and systemic secondary amyloidosis (AA) in 3 patients. A peculiar pattern of relatively frequent lymph node (31%) and lung (17%) involvement was noted in patients with systemic AL amyloidosis. Response to alkylating agents was poor, with a hematologic response in 37%, a complete remission in 0%, and an organ response in 21%. Response to hematopoietic stem cell transplantation showed a hematologic response in 100% with complete remission in 75% and an organ response in 75%. Purine analogs and rituximab induced a hematologic response in 73% and 60%, respectively, with complete remission in 9% and 0% and an organ response in 55% and 0%, respectively. In multivariate analysis, prognostic factors for survival were serum albumin level < or =3.5 g/dL (p = 0.018) and heart involvement (p = 0.0034). Further prospective studies are needed in patients with IgM-related amyloidosis, with special emphasis on treatment options: hematopoietic stem cell transplantation and purine analogs could represent the most effective therapies. The identification of adverse prognostic factors of survival could be useful for those managing and making treatment decisions for these patients.