Biologic activity of cold-reacting autoantibodies (first of two parts)

Waldenström Macroglobulinemia - A State-of-the-Art Review: Part 1: Epidemiology, Pathogenesis, Clinicopathologic Characteristics, Differential Diagnosis, Risk Stratification, and Clinical Problems

Waldenström macroglobulinemia (WM) is an infrequent variant of lymphoma, classified as a B-cell malignancy identified by the presence of IgM paraprotein, infiltration of clonal, small lymphoplasmacytic B cells in the bone marrow, and the MYD88 L265P mutation, which is observed in over 90% of cases. The direct invasion of the malignant cells into tissues like lymph nodes and spleen, along with the immune response related to IgM, can also lead to various health complications, such as cytopenias, hyperviscosity, peripheral neuropathy, amyloidosis, and Bing-Neel syndrome. Chemoimmunotherapy has historically been considered the preferred treatment for WM, wherein the combination of rituximab and nucleoside analogs, alkylating drugs, or proteasome inhibitors has exhibited notable efficacy in inhibiting tumor growth. Recent studies have provided evidence that Bruton Tyrosine Kinase inhibitors (BTKI), either used independently or in conjunction with other drugs, have been shown to be effective and safe in the treatment of WM. The disease is considered to be non-curable, with a median life expectancy of 10 to 12 years.

Sutimlimab provides clinically meaningful improvements in patient-reported outcomes in patients with cold agglutinin disease: Results from the randomised, placebo-controlled, Phase 3 CADENZA study

Cold agglutinin disease (CAD) is a rare chronic autoimmune haemolytic anaemia, driven mainly by classical complement pathway activation, leading to profound fatigue and poor quality of life. In the Phase 3 CADENZA trial, sutimlimab-a C1s complement inhibitor-rapidly halted haemolysis, increased haemoglobin levels and improved fatigue versus placebo in patients with CAD without a recent history of transfusion. Patient-reported outcomes (PROs) included Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue), 12-Item Short Form Health Survey (SF-12), EuroQol visual analogue scale (EQ-VAS), Patient Global Impression of Change (PGIC) and Patient Global Impression of (fatigue) Severity (PGIS). Sutimlimab resulted in significant rapid and meaningful improvements versus placebo in PROs. From Week 1, the FACIT-Fatigue mean score increased >5 points above baseline (considered a clinically important change [CIC]). Least-squares (LS) mean change in FACIT-Fatigue score from baseline to treatment assessment timepoint was 10.8 vs. 1.9 points (sutimlimab vs. placebo; p < 0.001). Improvements in physical (PCS) and mental (MCS) component scores of the SF-12 were also considered CICs (LS mean changes from baseline to Week 26: PCS 5.54 vs. 1.57 [p = 0.064]; MCS 5.65 vs. -0.48 [p = 0.065]). These findings demonstrate that in addition to improving haematologic parameters, sutimlimab treatment demonstrates significant patient-reported benefits. Study registered at www.clinicaltrials.gov: NCT03347422.

Sutimlimab in patients with cold agglutinin disease: results of the randomized placebo-controlled phase 3 CADENZA trial

Sutimlimab, a first-in-class humanized immunoglobulin G4 (IgG4) monoclonal antibody that selectively inhibits the classical complement pathway at C1s, rapidly halted hemolysis in the single-arm CARDINAL study in recently transfused patients with cold agglutinin disease (CAD). CADENZA was a 26-week randomized, placebo-controlled phase 3 study to assess safety and efficacy of sutimlimab in patients with CAD without recent (within 6 months prior to enrollment) transfusion history. Forty-two patients with screening hemoglobin ≤10 g/dL, elevated bilirubin, and ≥1 CAD symptom received sutimlimab (n = 22) or placebo (n = 20) on days 0 and 7 and then biweekly. Composite primary endpoint criteria (hemoglobin increase ≥1.5 g/dL at treatment assessment timepoint [mean of weeks 23, 25, 26], avoidance of transfusion, and study-prohibited CAD therapy [weeks 5-26]) were met by 16 patients (73%) on sutimlimab, and 3 patients (15%) on placebo (odds ratio, 15.9 [95% confidence interval, 2.9, 88.0; P < .001]). Sutimlimab, but not placebo, significantly increased mean hemoglobin and FACIT-Fatigue scores at treatment assessment timepoint. Sutimlimab normalized mean bilirubin by week 1. Improvements correlated with near-complete inhibition of the classical complement pathway (2.3% mean activity at week 1) and C4 normalization. Twenty-one (96%) sutimlimab patients and 20 (100%) placebo patients experienced ≥1 treatment-emergent adverse event. Headache, hypertension, rhinitis, Raynaud phenomenon, and acrocyanosis were more frequent with sutimlimab vs placebo, with a difference of ≥3 patients between groups. Three sutimlimab patients discontinued owing to adverse events; no placebo patients discontinued. These data demonstrate that sutimlimab has potential to be an important advancement in the treatment of CAD. This trial was registered at www.clinicaltrials.gov as #NCT03347422.

Inhibition of complement C1s in patients with cold agglutinin disease: lessons learned from a named patient program

Cold agglutinin disease (CAD) causes predominantly extravascular hemolysis and anemia via complement activation. Sutimlimab is a novel humanized monoclonal antibody directed against classical pathway complement factor C1s. We aimed to evaluate the safety and efficacy of long-term maintenance treatment with sutimlimab in patients with CAD. Seven CAD patients treated with sutimlimab as part of a phase 1B study were transitioned to a named patient program. After a loading dose, patients received biweekly (once every 2 weeks) infusions of sutimlimab at various doses. When a patient's laboratory data showed signs of breakthrough hemolysis, the dose of sutimlimab was increased. Three patients started with a dose of 45 mg/kg, another 3 with 60 mg/kg, and 1 with a fixed dose of 5.5 g every other week. All CAD patients responded to re-treatment, and sutimlimab increased hemoglobin from a median initial level of 7.7 g/dL to a median peak of 12.5 g/dL (P = .016). Patients maintained near normal hemoglobin levels except for a few breakthrough events that were related to underdosing and which resolved after the appropriate dose increase. Four of the patients included were eventually treated with a biweekly 5.5 g fixed-dose regimen of sutimlimab. None of them had any breakthrough hemolysis. All patients remained transfusion free while receiving sutimlimab. There were no treatment-related serious adverse events. Overlapping treatment with erythropoietin, rituximab, or ibrutinib in individual patients was safe and did not cause untoward drug interactions. Long-term maintenance treatment with sutimlimab was safe, effectively inhibited hemolysis, and significantly increased hemoglobin levels in re-exposed, previously transfusion-dependent CAD patients.

Sutimlimab in Cold Agglutinin Disease

BACKGROUND

Cold agglutinin disease is a rare autoimmune hemolytic anemia characterized by hemolysis that is caused by activation of the classic complement pathway. Sutimlimab, a humanized monoclonal antibody, selectively targets the C1s protein, a C1 complex serine protease responsible for activating this pathway.

METHODS

We conducted a 26-week multicenter, open-label, single-group study to assess the efficacy and safety of intravenous sutimlimab in patients with cold agglutinin disease and a recent history of transfusion. The composite primary end point was a normalization of the hemoglobin level to 12 g or more per deciliter or an increase in the hemoglobin level of 2 g or more per deciliter from baseline, without red-cell transfusion or medications prohibited by the protocol.

RESULTS

A total of 24 patients were enrolled and received at least one dose of sutimlimab; 13 patients (54%) met the criteria for the composite primary end point. The least-squares mean increase in hemoglobin level was 2.6 g per deciliter at the time of treatment assessment (weeks 23, 25, and 26). A mean hemoglobin level of more than 11 g per deciliter was maintained in patients from week 3 through the end of the study period. The mean bilirubin levels normalized by week 3. A total of 17 patients (71%) did not receive a transfusion from week 5 through week 26. Clinically meaningful reductions in fatigue were observed by week 1 and were maintained throughout the study. Activity in the classic complement pathway was rapidly inhibited, as assessed by a functional assay. Increased hemoglobin levels, reduced bilirubin levels, and reduced fatigue coincided with inhibition of the classic complement pathway. At least one adverse event occurred during the treatment period in 22 patients (92%). Seven patients (29%) had at least one serious adverse event, none of which were determined by the investigators to be related to sutimlimab. No meningococcal infections occurred.

CONCLUSIONS

In patients with cold agglutinin disease who received sutimlimab, selective upstream inhibition of activity in the classic complement pathway rapidly halted hemolysis, increased hemoglobin levels, and reduced fatigue. (Funded by Sanofi; CARDINAL ClinicalTrials.gov number, NCT03347396.).

I-branched carbohydrates as emerging effectors of malignant progression

Cell surface carbohydrates, termed "glycans," are ubiquitous posttranslational effectors that can tune cancer progression. Often aberrantly displayed or found at atypical levels on cancer cells, glycans can impact essentially all progressive steps, from malignant transformation to metastases formation. Glycans are structural entities that can directly bind promalignant glycan-binding proteins and help elicit optimal receptor-ligand activity of growth factor receptors, integrins, integrin ligands, lectins, and other type-1 transmembrane proteins. Because glycans play an integral role in a cancer cell's malignant activity and are frequently uniquely expressed, preclinical studies on the suitability of glycans as anticancer therapeutic targets and their promise as biomarkers of disease progression continue to intensify. While sialylation and fucosylation have predominated the focus of cancer-associated glycan modifications, the emergence of blood group I antigens (or I-branched glycans) as key cell surface moieties capable of modulating cancer virulence has reenergized investigations into the role of the glycome in malignant progression. I-branched glycans catalyzed principally by the I-branching enzyme GCNT2 are now indicated in several malignancies. In this Perspective, the putative role of GCNT2/I-branching in cancer progression is discussed, including exciting insights on how I-branches can potentially antagonize the cancer-promoting activity of β-galactose-binding galectins.

Inhibition of complement C1s improves severe hemolytic anemia in cold agglutinin disease: a first-in-human trial

Cold agglutinin disease is a difficult-to-treat autoimmune hemolytic anemia in which immunoglobulin M antibodies bind to erythrocytes and fix complement, resulting in predominantly extravascular hemolysis. This trial tested the hypothesis that the anti-C1s antibody sutimlimab would ameliorate hemolytic anemia. Ten patients with cold agglutinin disease participated in the phase 1b component of a first-in-human trial. Patients received a test dose of 10-mg/kg sutimlimab followed by a full dose of 60 mg/kg 1 to 4 days later and 3 additional weekly doses of 60 mg/kg. All infusions were well tolerated without premedication. No drug-related serious adverse events were observed. Seven of 10 patients with cold agglutinin disease responded with a hemoglobin increase >2 g/dL. Sutimlimab rapidly increased hemoglobin levels by a median of 1.6 g/dL within the first week, and by a median of 3.9 g/dL (interquartile range, 1.3-4.5 g/dL; 95% confidence interval, 2.1-4.5) within 6 weeks (P = .005). Sutimlimab rapidly abrogated extravascular hemolysis, normalizing bilirubin levels within 24 hours in most patients and normalizing haptoglobin levels in 4 patients within 1 week. Hemolytic anemia recurred when drug levels were cleared from the circulation 3 to 4 weeks after the last dose of sutimlimab. Reexposure to sutimlimab in a named patient program recapitulated the control of hemolytic anemia. All 6 previously transfused patients became transfusion-free during treatment. Sutimlimab was safe, well tolerated, and rapidly stopped C1s complement-mediated hemolysis in patients with cold agglutinin disease, significantly increasing hemoglobin levels and precluding the need for transfusions. This trial was registered at www.clinicaltrials.gov as #NCT02502903.

Waldenström's macroglobulinemia - a review

Waldenström's macroglobulinemia (WM) is a lymphoproliferative disease of B lymphocytes, characterized by a lymphoplasmocytic lymphoma in the bone marrow and by IgM monoclonal hypergammaglobulinemia. It was first described in 1944 by Jan Gösta Waldenström, reporting two patients with oronasal bleeding, lymphadenopathy, anemia, thrombocytopenia, high erythrocyte sedimentation rate and serum viscosity, normal radiography and bone marrow infiltrated by lymphoid cells. The WM is a rare disease with a typically indolent clinical course, affecting mainly individuals aged between 63 and 68 years. Most patients have clinical signs and symptoms related to hyperviscosity resulting from IgM monoclonal gammopathy, and/or cytopenias resulting from bone marrow infiltration by lymphoma. The differential diagnosis with other lymphomas is essential for the assessment of prognosis and therapeutic approach. Treatment of patients with asymptomatic WM does not improve the quality of life of patients, or increase their survival, being recommended, therefore, their follow-up. For the treatment of symptomatic patients, alkylating agents, purine analogs and anti-CD20 monoclonal antibodies are used. However, the disease is incurable and the response to therapy is not always favorable. Recent studies have shown promising results with bortezomib, an inhibitor of proteasomes, and some patients respond to thalidomide. In patients with relapse or refractory to therapy, autologous transplantation may be indicated. The aim of this paper is to describe in detail the current knowledge on the pathophysiology of WM, main clinical manifestations, diagnosis, prognosis and treatment.

Waldenström macroglobulinemia: clinical and immunological aspects, natural history, cell of origin, and emerging mouse models

Waldenström macroglobulinemia (WM) is a rare and currently incurable neoplasm of IgM-expressing B-lymphocytes that is characterized by the occurrence of a monoclonal IgM (mIgM) paraprotein in blood serum and the infiltration of the hematopoietic bone marrow with malignant lymphoplasmacytic cells. The symptoms of patients with WM can be attributed to the extent and tissue sites of tumor cell infiltration and the magnitude and immunological specificity of the paraprotein. WM presents fascinating clues on neoplastic B-cell development, including the recent discovery of a specific gain-of-function mutation in the MYD88 adapter protein. This not only provides an intriguing link to new findings that natural effector IgM⁺IgD⁺ memory B-cells are dependent on MYD88 signaling, but also supports the hypothesis that WM derives from primitive, innate-like B-cells, such as marginal zone and B1 B-cells. Following a brief review of the clinical aspects and natural history of WM, this review discusses the thorny issue of WM's cell of origin in greater depth. Also included are emerging, genetically engineered mouse models of human WM that may enhance our understanding of the biologic and genetic underpinnings of the disease and facilitate the design and testing of new approaches to treat and prevent WM more effectively.

How I treat Waldenström macroglobulinemia

Waldenström macroglobulinemia (WM) is a distinct B-cell disorder resulting from the accumulation, predominantly in the bone marrow, of clonally related IgM-secreting lymphoplasmacytic cells. Genetic factors play an important role, with 20% of patients demonstrating a familial predisposition. Asymptomatic patients should be observed. Patients with a disease-related hemoglobin level less than 10 g/L, platelet count less than 100 × 109/L, bulky adenopathy or organomegaly, symptomatic hyperviscosity, peripheral neuropathy, amyloidosis, cryoglobulinemia, cold-agglutinin disease, or evidence of disease transformation should be considered for therapy. Plasmapheresis should be considered for symptomatic hyperviscosity and for prophylaxis in patients in whom rituximab therapy is contemplated. The use of rituximab as monotherapy or in combination with cyclophosphamide, nucleoside analog, bortezomib, or thalidomide-based regimens can be considered for the first-line therapy of WM and should take into account specific treatment goals, future autologous stem cell transplantation eligibility, and long-term risks of secondary malignancies. In the salvage setting, the reuse or use of an alternative frontline regimen can be considered as well as bortezomib, alemtuzumab, and stem cell transplantation. Newer agents, such as bendamustine and everolimus, can also be considered in the treatment of WM.

Recurrent acute renal failure complicating IgG warm-type autoimmune intravascular haemolysis

A 44-year-old woman experienced recurrent episodes of massive intravascular haemolysis complicated by acute oliguric renal failure over a period of 22 years. The haemolysis was induced by IgG warm type autoantibody and complement and responded to corticosteroid therapy. The renal failure was treated effectively by dialysis. To our knowledge, such a life long occurrence of recurrent intravascular haemolysis induced by IgG warm type autoantibodies together with renal failure has not been reported before.

Cold antibody autoimmune hemolytic anemias

The cold antibody autoimmune hemolytic anemias (AIHAs) are primarily comprised of cold agglutinin syndrome (CAS) and paroxysmal cold hemoglobinuria (PCH) but, in addition, there are unusual instances in which patients satisfy the serologic criteria of both warm antibody AIHA and CAS ("mixed AIHA"). CAS characteristically occurs in middle-aged or elderly persons, often with signs and symptoms exacerbated by cold. The responsible antibody is of the IgM immunoglobulin class, is maximally reactive in the cold but with reactivity up to at least 30 degrees C. Therapy is often ineffective, but newer agents such as rituximab have been beneficial in some patients. PCH occurs primarily in children, often after an upper respiratory infection. The causative antibody is of the IgG immunoglobulin class and is a biphasic hemolysin that is demonstrated by incubation in the cold followed by incubation at 37 degrees C in the presence of complement. Acute attacks are frequently severe but the illness characteristically resolves spontaneously within a few days to several weeks after onset and rarely recurs. Treatment consists of supportive care, with transfusions frequently being needed.

Waldenström macroglobulinemia

In the past 36 months, new developments have occurred both in the understanding of the biology of Waldenström macroglobulinemia (WM) and in therapeutic options for WM. Here, we review the classification, clinical features, and diagnostic criteria of the disease. WM is a B-cell neoplasm characterized by lymphoplasmacytic infiltration of the bone marrow and a monoclonal immunoglobulin M (IgM) protein. The symptoms of WM are attributable to the extent of tumor infiltration and to elevated IgM levels. The most common symptom is fatigue attributable to anemia. The prognostic factors predictive of survival include the patient's age, β2-microglobulin level, monoclonal protein level, hemoglobin concentration, and platelet count. Therapy is postponed for asymptomatic patients, and progressive anemia is the most common indication for initiation of treatment. The main therapeutic options include alkylating agents, nucleoside analogues, and rituximab. Studies involving combination chemotherapy are ongoing, and preliminary results are encouraging. No specific agent or regimen has been shown to be superior to another for treatment of WM. Novel agents such as bortezomib, perifosine, atacicept, oblimersen sodium, and tositumomab show promise as rational targeted therapy for WM.

Waldenström's macroglobulinemia

The diagnosis of Waldenström's macroglobulinemia (WM) requires evidence of bone-marrow infiltration by lymphoplasmacytoid lymphoma and detection of serum monoclonal protein of IgM type. The normal counterpart of the WM malignant cell is believed to be a postgerminal-center B cell. The clinical manifestations and laboratory abnormalities associated with WM are related to direct tumor infiltration and to the amount and specific properties of IgM. Asymptomatic patients should be followed without treatment. When treatment is indicated, the three main choices for systemic frontline treatment are chlorambucil, the nucleoside analogues fludarabine or cladribine and the monoclonal antibody rituximab. There is evidence that high-dose therapy with autologous stem-cell transplantation is effective even in patients with advanced and resistant disease. Patient's age, hemoglobin and serum beta2-microglobulin before treatment are important prognostic variables which correlate with survival.

Agglutinines froides, circonstances de découverte chez l’adulte et signification en pratique clinique : analyse rétrospective à propos de 58 patients

PURPOSE

To describe clinical, biological characteristics and associated diseases of cold agglutinins in adults.

METHODS

Retrospective study in a single department of internal medicine from 1997 to 2002. The inclusion criteria were a positive direct Coombs test and a positive research for cold-reactive autoantibodies. We recorded for each patient: clinical presentation at onset and during follow-up, biological parameters of haemolysis, biological characteristics of the cold agglutinin and associated diseases.

RESULTS

Fifty-eight patients (34 females, 24 males), with medium age of 58.8 were included in the study. Clinical presentation was highly variable between acute life-threatening haemolysis and absence of symptoms. Results of direct antiglobulin test were C3 (74%), IgG + C3 (22.4%), IgG (3.4%). Titer, thermal amplitude, strength and specificity of Coombs test were correlated, in all cases except 6, with cold agglutinin haemolytic activity. In 77.6% of cases cold agglutinin was secondary; related to: autoimmune disorders (n = 19), lymphoproliferative disorders (n = 11) and infections (n = 10).

CONCLUSION

Clinical presentation of cold agglutinin is highly variable and not always related to the biological characteristics of the bound antibody (titer, thermal amplitude, specificity). In our single center study, diseases associated with cold agglutinin were various with the highest frequency of auto-immune disorders. Our study underlined also the high frequency of lymphoproliferative disorders and justifies a close follow-up of these patients. Finally, we reported a high frequency of hepatitis C virus infection among the infectious aetiologies.

A Last Resort Modality Using Cryofiltration Apheresis for the Treatment of Cold Hemagglutinin Disease in a Veterans Administration Hospital

Cold hemagglutinin disease is a cold autoimmune hemolytic anemia (cAIHA) caused by an autoantibody, such as IgM, directed against the I-antigen present on the surface of erythrocytes. Cold exposure can activate this system causing hemolysis, hemagglutination, microvascular thrombosis, or acrocyanosis. Thus, surgical procedures requiring hypothermia, such as coronary artery bypass surgery, present a significant problem in patients with cAIHA. The purpose of this study was to evaluate the safety and effectiveness of cryofiltration apheresis (CFA), used as a last resort, for the treatment of cAIHA. Effectiveness was evaluated by clinical assessment and laboratory evaluations of cold agglutinin titer, immunoglobulins, and other plasma proteins. Safety was evaluated by vital signs, monitoring, and laboratory measurements of complements, hematology and blood chemistry. Five patients with cAIHA were treated by CFA using the cryoglobulin (CG) filter (Pall Medical, Ann Arbor, MI, USA). Four patients received only one CFA procedure, while one patient received four CFA treatments. The cold agglutinin titers were fairly low, ranging from 1 : 1 to 1 : 2048. However, a wide thermal amplitude(4-37 degrees C) was observed in most patients. Two out of five patients responded favorably with reduction in titer. The two responders had acute forms of cAIHA with serum positive for cryoglobulins. The three non-responders had chronic forms of cAIHA with negative cryoglobulins. CFA effectively removed cryoprotein precipitates while conserving other plasma components. The CG filter was biocompatible with no complement activation or observed complications due to CFA or CG filter. While the mechanism of action in treating this type of patient population with CFA is unknown, the plausible theories are discussed.

Cold agglutinins complicating repair of aortic dissection using cardiopulmonary bypass and hypothermic circulatory arrest: case report and review

Cold agglutinins (CAs) are autoantibodies that react reversibly with red blood cells (RBCs) at temperatures of, or below, the thermal amplitude for agglutination. This results in increased blood viscosity and sludging of RBC, and may impair perfusion to various organ systems. Although this phenomenon appears rarely in the clinical arena, the incidence of CA is increased substantially in cardiac surgery due to the routine use of hypothermia for organ preservation and systemic metabolic reduction. Once activated, CA are associated with microvascular occlusion, hemolysis, complement fixation, renal and hepatic insufficiency, cerebral insult, and myocardial infarction. Complications from CA may be minimized with appropriate screening, detection, and management in the perioperative period. A prototypical case is described, and pertinent issues regarding CA are reviewed.

Continual low-level activation of the classical complement pathway

There is evidence that the classical complement pathway may be activated via a "C1-tickover" mechanism, analogous to the C3-tickover of the alternative pathway. We have quantitated and characterized this pathway of complement activation. Analysis of freshly collected mouse and human plasma revealed that spontaneous C3 activation rapidly occurred with the generation of C3 fragments in the plasma. By the use of complement- and Ig-deficient mice it was found that C1q, C4, C2, and plasma Ig were all required for this spontaneous C3 activation, with the alternative complement pathway further amplifying C3 fragment generation. Study of plasma from a human with C1q deficiency before and after therapeutic C1q infusion confirmed the existence of a similar pathway for complement activation in humans. Elevated levels of plasma C3 were detected in mice deficient in complement components required for activation of either the classical or alternative complement pathways, supporting the hypothesis that there is continuous complement activation and C3 consumption through both these pathways in vivo. Blood stasis was found to stimulate C3 activation by classical pathway tick-over. This antigen-independent mechanism for classical pathway activation may augment activation of the complement system at sites of inflammation and infarction.

Cold haemagglutinin disease: clinical significance of serum haemolysins

Two hundred and twenty-one patients with cold haemagglutinins of thermal amplitude > or = 30 degrees C (considered to be a reasonable indicator of clinical significance) were classified by in vitro haemolysin activity into three groups. Group 1 contained 116 individuals in whom haemolysins were never detected; the 74 patients in Group 2 had monophasic haemolysins alone; whereas both monophasic and biphasic haemolysins were detected in the 31 Group 3 patients. There was a significantly higher proportion of patients in Groups 2 and 3 with haptoglobin levels < 0.1 g/l compared with Groups 1 and 2, respectively (P < 0.005 and P < 0.001). Direct antiglobulin test results showed that the autoimmune response became more complex and IgM predominant through Groups 1-3, resulting in an increasing ability to activate complement which was reflected in increasing haemolysin activity and number of patients with active haemolysis. The 31 patients in Group 3 were mostly elderly (median age 71 years at presentation) and the majority had chronic cold haemagglutinin disease (CHAD), several in association with lymphoid neoplasms or carcinomas; only four had acute CHAD. The natural history of idiopathic chronic CHAD was of mild, well compensated haemolysis, punctuated by severe acute episodes necessitating intensive therapy. The condition often remained active for long periods and did not appear to affect natural lifespan. In some cases, no treatment (or just warmth) was needed; in others continuous or intermittent prednisolone and/or chlorambucil were effective; yet others required a greater variety and more intense therapy, or treatment of associated conditions. Blood transfusion support was frequently required when haemolysis was severe.

Management of cold agglutination syndrome

Cold haemagglutination syndrome is difficult to treat. Fortunately it seldom needs treating. In most cases cold agglutinins are an incidental finding representing either normality or a benign chronic monoclonal gammopathy that does not cause ill health. Two sorts of symptoms are likely in the more severe cases. Acrocyanosis is usually treated by keeping the patient warm and if necessary removing him or her to Florida or the Canary Islands. In the rare cases of haemolytic anaemia, an underlying lymphoid tumour should be sought and treated. If none exists, then it is unlikely that the treatments that are useful in warm antibody haemolytic anaemia will be helpful. Plasma exchange ought to work but in practice there are frequently problems of red cell agglutination within the cell separator or the plastic tubes. For this reason plasma exchange within a heated room is advocated. When cardiac surgery is contemplated pre-operative plasma exchange is sometimes helpful, or the heart may be stopped by potassium solutions and the operation is carried out in the warm.

Waldenström's macroglobulinemia: clinical features, complications, and management

PURPOSE

To review the clinical features, complications, and treatment of Waldenström's macroglobulinemia, a low-grade lymphoproliferative disorder that produces monoclonal immunoglobulin (Ig) M.

METHODS

A review of published reports was facilitated by the use of a MEDLINE computer search and by manual search of the Index Medicus.

RESULTS

The clinical manifestations associated with Waldenström's macroglobulinemia can be classified according to those related to direct tumor infiltration, to the amount and specific properties of circulating IgM, and to the deposition of IgM in various tissues. Asymptomatic patients should be followed without treatment. For symptomatic patients, standard treatment consists primarily of oral chlorambucil; nucleoside analogs, such as fludarabine and cladribine, are effective in one third of previously treated patients and in up to 80% of previously untreated patients. Preliminary evidence suggests that anti-CD20 monoclonal antibody may be active in about 30% of previously treated patients and that high-dose therapy with autologous stem-cell rescue is effective in most patients, including some with resistance to nucleoside analogs.

CONCLUSION

Waldenström's macroglobulinemia has a wide clinical spectrum that practicing physicians need to recognize early to reach the correct diagnosis. When therapy is indicated, oral chlorambucil is the standard primary treatment, but cladribine or fludarabine can be used when a rapid cytoreduction is desirable. Prospective randomized trials are required to elucidate the impact of nucleoside analogs on patients' survival. A nucleoside analog is the treatment of choice for patients who have been previously treated with an alkylating agent.

Waldenström's macroglobulinemia

Waldenström's macroglobulinemia is an unusual low-grade lymphoplasmacytic lymphoma characterized by the production of monoclonal IgM. The clinical manifestations associated with WM can be classified as those related to direct tumor infiltration, by the amount and specific properties of circulating IgM, and by the deposition of IgM in various tissues. Asymptomatic patients should be followed without treatment. The management of the disease relies on the administration of systemic chemotherapy to reduce tumor load and on the application of plasmapheresis to remove circulating IgM. Standard treatment consists of oral chlorambucil, which induces response in at least 50% of patients, resulting in a median survival of approximately 5 years. Nucleoside analogues (cladribine, fludarabine) are effective in most previously untreated patients. These agents are the treatment of choice for patients with disease resistant to alkylating agents. New treatment approaches include high-dose therapy with stem-cell support and administration of monoclonal anti-CD20 antibodies.

Plasmapheresis and paraproteinemia: cryoprotein-induced diseases, monoclonal gammopathy, Waldenström's macroglobulinemia, hyperviscosity syndrome, multiple myeloma, light chain disease, and amyloidosis

Therapeutic plasmapheresis has been in widespread use as either a primary or adjunctive therapy in the United States since the 1960s. There are several types of plasmapheresis procedures used to treat various diseases. Plasma exchange with a centrifugal plasma separator using replacement fluid such as human albumin solution is the most widely used method in the United States. Other forms of plasmapheresis include membrane plasma separation, membrane fractionation, cryofiltration apheresis, immunoadsorption, and chemical affinity column pheresis. Therapeutic plasmapheresis has been used for the treatment of paraproteinemia to remove harmful paraproteins. Paraproteinemia is a disease classification in which abnormal or large amounts of plasma proteins such as cryoproteins or immunoglobulins are produced. In most cases, plasmapheresis is used in combination with corticosteroids and immunosuppressive drugs to prevent production of abnormal proteins or to treat the underlying disease. Cryoprotein-induced diseases, which include cryoglobulinemia, cryofibrinogenemia, and cold IgM antibody agglutinin with cryoglobulin properties, are a subclass of paraproteinemia. Other categories of paraproteinemia include monoclonal gammopathy, Waldenström's macroglobulinemia, hyperviscosity syndrome, multiple myeloma, light chain disease, and amyloidosis. Some of these diseases may be interrelated, and they may be associated with one another. In this review paper, we discuss the role of plasmapheresis in the specific classes of paraproteinemia in the United States, including our own experience.

Cutaneous necrosis by cold agglutinins associated with glomeruloid reactive angioendotheliomatosis

The cold agglutinin syndrome is a haemolytic disorder that can cause skin lesions, mainly on the acral areas, with acrocyanosis being the most frequent manifestation. Cutaneous necrosis due to cold agglutinins is very rare. Reactive angioendotheliomatosis (RAE) is an uncommon condition that exclusively affects the skin, characterized by a hyperplasia of endothelial cells and pericytes that can result in the formation of glomeruloid structures. The association of cold agglutinin syndrome with glomeruloid RAE has not been previously described. We report a 70-year-old man diagnosed as having a B-cell low-grade non-Hodgkin's lymphoma. He had two episodes of cutaneous necrosis in acral areas which were related to exposure to cold and due to IgM anti-I(T) cold agglutinins. Biopsy specimens showed vessel proliferations composed of dilated vascular spaces in the dermis and subcutis. Some vessel lumina were partially occluded by eosinophilic thrombi of fibrin and erythrocytes. Numerous closely packed capillaries were observed within pre-existing dilated vessels. This intravascular proliferation of capillaries displayed a glomeruloid pattern. We emphasize the possible presence of a cold agglutinin syndrome in patients with skin necrosis and findings of RAE with a glomeruloid pattern. Cold agglutinaemia may cause these distinctive histological changes.

Guillain-Barré syndrome associated with IgG anti-GM1b antibody subsequent to Mycoplasma pneumoniae infection

Sera from patients with Guillain-Barré syndrome (GBS) frequently have antibodies to various gangliosides. We report a girl with GBS after Mycoplasma pneumoniae infection who had serum IgG antibody to GM1b ganglioside as well as the cold agglutinins. The cold agglutinins are polyclonal IgM autoantibodies to 'I' antigen on erythrocytes. Ganglioside GM1b contains the terminal moiety shared with sialylated I antigen, a main receptor for M. pneumoniae. In this patient, the anti-GM1b antibody may be elicited in a similar mechanism producing anti-I antibody, and functioned in the development of GBS.

Hemolytic disorders associated with cancer

Three principal environmental causes of hemolytic anemia in malignancy have been identified: (1) hemolysis mediated by auto-antibodies to red cells; (2) hemolysis due to microangiopathic disorders; and (3) chemotherapy-induced red cell destruction. These three environmental stressors occur rarely in cancer patients, and they form the subject of this review.

Cardiac surgery and cold-reactive proteins

Cold agglutinins are commonly found in sera of healthy persons. They rarely become clinically apparent due to their activity at low temperatures. In these patients, cardiovascular operations requiring hypothermia can result in complications such as hemolysis, renal failure, and myocardial damage and can cause unexpected morbidity and mortality. The literature on cold-reactive proteins is reviewed, and methods of diagnosis and management related to cardiac surgery are suggested. Ideally all patients should be routinely tested preoperatively for the antibodies, and appropriate changes in cardiopulmonary bypass and myocardial management plans should be made in positive patients. Preoperative plasmapheresis may be a useful adjunct, especially in patients requiring operation under profound hypothermia and circulatory arrest. Currently, warm heart surgery appears to be the most expedient method. Unexpected detection of agglutination during operation or hemolysis after operation requires a specific treatment plan.

Waldenström's macroglobulinemia with an IgM paraprotein that is both a cold agglutinin and a cryoglobulin and has a suppressive effect on progenitor cell growth

BACKGROUND

A patient with Waldenström's macroglobulinemia was admitted to the hospital with fever, leg pain, and dyspnea. The patient had gas gangrene of the left leg that required above-the-knee amputation. Plasmapheresis was instituted to treat hyperviscosity.

STUDY DESIGN AND METHODS

The patient's serum contained an IgM-kappa paraprotein, a cryoglobulin, and a cold agglutinin. The serum was studied.

RESULTS

The patient's red cells typed as A1, Rh-positive. The direct antiglobulin test was negative. The serum contained a cold agglutinin with anti-Pr cold agglutinin specificity (titer 4096). Maximal thermal range was 30 degrees C. Following dithiothreitol treatment, the cold agglutinin activity disappeared. The serum IgM concentration in the tested sample was 62.3 g per L. The cold agglutinin titer in the supernatant after removal of the cryoglobulin was 256, and the IgM level was 0.31 g per L. Redissolving the cryoglobulin in a equivalent volume of saline resulted in a cold agglutinin titer of 4096 and an IgM level of 68.4 g per L. These results indicate that the cryoglobulin and the cold agglutinin are the same paraprotein. Serum protein electrophoresis using agarose gel and immunofixation of the serum revealed an IgM-kappa monoclonal band. Progenitor cell assays were performed by adding the patient's serum at final concentrations of 0, 1, 5 and 10 percent (vol/vol) to patient's and normal donor's peripheral blood mononuclear cells. Inhibition of burst-forming units-erythroid and colony-forming units-granulocyte/macrophage by the patient's serum was demonstrated. Appropriate controls and the use of the serum of another patient with Waldenström's macroglobulinemia did not suppress progenitor cell growth. The patient's serum inhibited colony formation in a dose-response fashion.

CONCLUSION

Reports of cryoprecipitable cold agglutinins are rare. This case is unusual because the IgM-kappa paraprotein was also a cold agglutinin with anti-Pr specificity and erythroid and granulocyte-macrophage progenitor cell-suppressive properties.

Mucosa-associated lymphoid tissue lymphoma of the lung with cold-reacting autoantibody-mediated hemolytic anemia

Mucosa-associated lymphoid tissue lymphoma (MALT-oma) of the lung is a rare low-grade B cell lymphoma arising from bronchus-associated lymphoid tissue. This report concerns a 39-year-old woman with bilateral diffuse alveolar consolidations and cold-reacting autoantibody-mediated hemolytic anemia. Open-lung biopsy showed angulated lymphoid cells with lymphoepithelial lesions. Immunocytochemistry revealed that the lymphoid cells were positive for CD19, CD20, and IgM (lambda), which was consistent with immunophenotype of MALToma. The serum immunoelectrophoresis demonstrated IgM (lambda) monoclonal gammopathy. The association of cold-reacting auto-antibody-mediated hemolytic anemia with MALToma, to our knowledge, has never been reported before in the English language.

Naturally occurring anti-i/I cold agglutinins may be encoded by different VH3 genes as well as the VH4.21 gene segment

In the current study, we wished to determine if the V regions encoding the naturally occurring anti-i/I Cold Agglutinins (anti-i/I CA) differ from pathogenic anti-i/I CA that are exclusively encoded by the VH4.21 gene. After EBV transformation of B lymphocytes, we generated one anti-I secreting clone from each of two individuals; clone 4G (individual CM, PBL) and clone Sp1 (individual SC, spleen). Clone 4G expresses a VH3 gene sequence that is 92% homologous to the germline gene WHG26. Clone Sp1 also expresses a VH3 gene that is 98% homologous to the fetally rearranged M85/20P1 gene. Another clone, Sp2 (anti-i specificity), from individual SC is 98% homologous to the germline gene VH4.21. For correlation, we studied anti-i/I CA fractions purified from 15 normal sera and found no or relatively small amounts of 9G4 (VH4.21 related idiotype) reactive IgM. Five cold agglutinin fractions contained large amounts of VH3-encoded IgM (compared to pooled normal IgM) by virtue of their binding to modified protein Staph A (SPA), and absorption of three CA fractions with modified SPA specifically removed anti-i/I binding specificity entirely. Collectively, the data indicate that naturally occurring anti-i/I CA may be encoded to a large extent by non-VH4.21-related genes, and that the VH4.21 gene is not uniquely required for anti-i/I specificity.

Cardiac operation without hypothermia for the patient with cold agglutinin

Recently, a new technique for myocardial protection that does not rely on hypothermia has been reported. In this method, the heart is continuously perfused with normothermic hyperkalemic blood cardioplegia during the cross-clamp period. Cardiac arrest is achieved and maintained using high levels of potassium. Hypothermia is not part of this technique; thus, the danger of hypothermia can be avoided in the patient with cold agglutinin disease without compromising myocardial protection. This communication reports our experience using retrograde continuous normothermic blood cardioplegia in one patient with potent cold agglutinins and severe coronary artery occlusive disease. This patient experienced an uneventful operative and postoperative course and remains asymptomatic, now more than two years after operation.