Lack of clinical efficacy of rituximab in the treatment of autoimmune neutropenia and pure red cell aplasia: implications for their pathophysiology

Phagocytosis of Mature Granulocytes by Bone Marrow Macrophages in an Elderly Man with Adult-Onset Primary Autoimmune Neutropenia

Adult-onset primary autoimmune neutropenia (AIN) is an extremely rare but sometimes life-threatening disease. Its pathophysiology is still to be clarified. We describe a case with adult-onset primary AIN with phagocytosis of mature granulocytes by macrophages in bone marrow. A 77-year-old male was referred to our hospital with severe neutropenia. Based on the normal cellular bone marrow without morphological dysplasia and the positivity of anti-neutrophil antibodies in the serum, adult-onset primary AIN was diagnosed. After five years from the initiation of granulocyte colony-stimulating-factor therapy, neutropenia had progressed. At that time, the second bone marrow examination revealed segmented neutrophils phagocytosed by macrophages. Continuous low dose prednisolone succeeded to increase the neutrophil count. An impressive morphological feature of AIN indicated the destruction of mature granulocytes in bone marrow by antibody-dependent cellular phagocytosis mediated by granulocyte-specific antibodies. More cases should be accumulated to elucidate the precise mechanism and establish the optimal therapy.

Diagnosis and therapeutic decision-making for the neutropenic patient

Determining the cause of a low neutrophil count in a pediatric or adult patient is essential for the hematologist's clinical decision-making. Fundamental to this diagnostic process is establishing the presence or lack of a mature neutrophil storage pool, as absence places the patient at higher risk for infection and the need for supportive care measures. Many diagnostic tests, eg, a peripheral blood smear and bone marrow biopsy, remain important tools, but greater understanding of the diversity of neutropenic disorders has added new emphasis on evaluating for immune disorders and genetic testing. In this article, a structure is provided to assess patients based on the mechanism of neutropenia and to prioritize testing based on patient age and hypothesized pathophysiology. Common medical quandaries including fever management, need for growth factor support, risk of malignant transformation, and curative options in congenital neutropenia are reviewed to guide medical decision-making in neutropenic patients.

How I manage acquired pure red cell aplasia in adults

Pure red cell aplasia (PRCA) is a rare hematological disorder with multiple etiologies. The multifaceted nature of this disease is emphasized by the variety of concomitant clinical features. Classic idiopathic presentation aside, prompt recognition of pathogenetic clues is important because of their diagnostic and therapeutic implications. As a consequence, treatment of PRCA is diverse and strictly dependent on the presented clinical scenario. Here, we propose a series of clinical vignettes that showcase instructive representative situations derived from our routine clinical practice. Using these illustrative clinical cases, we review the diagnostic workup needed for a precise diagnosis and the currently available therapeutic options, discussing their applications in regard to the various PRCA-associated conditions and individual patients' characteristics. Finally, we propose a treatment algorithm that may offer guidance for personalized therapeutic recommendations.

Pure Red Cell Aplasia with Del(20q) Sensitive for Immunosuppressive Treatment

Pure red cell aplasia (PRCA) is a rare syndrome that only affects the erythroid lineage. It is defined by a normocytic, normochromic anemia with a marked reticulocytopenia and severe reduction or absence of erythroid precursors in the bone marrow. Treatment of primary, idiopathic PRCA is immunosuppressive therapy. Although it is rare, isolated cytogenetic abnormalities can be seen in PRCA, and abnormal karyotype is associated with poor response to immunosuppressive therapy and poor prognosis. We describe a 77-year-old male with primary, idiopathic PRCA and a deletion of chromosome 20q, del(20q), in the bone marrow cells. He was successfully treated with immunosuppressive therapy and became transfusion-independent. The same cytogenetic abnormality has also been described in a few other reports; taken together, these observations suggest that del(20q) may represent a recurrent cytogenetic abnormality in PRCA. Our case report clearly illustrates that even patients with primary PRCA and an abnormal karyotype can respond to immunosuppression and become transfusion-independent.

Rational management approach to pure red cell aplasia

Pure red cell aplasia is an orphan disease, and as such lacks rationally established standard therapies. Most cases are idiopathic; a subset is antibody-mediated. There is overlap between idiopathic cases and those with T-cell large granular lymphocytic leukemia, hypogammaglobulinemia, and low-grade lymphomas. In each of the aforementioned, the pathogenetic mechanisms may involve autoreactive cytotoxic responses. We selected 62 uniformly diagnosed pure red cell aplasia patients and analyzed their pathophysiologic features and responsiveness to rationally applied first-line and salvage therapies in order to propose diagnostic and therapeutic algorithms that may be helpful in guiding the management of prospective patients, 52% of whom were idiopathic, while the others involved large granular lymphocytic leukemia, thymoma, and B-cell dyscrasia. T-cell-mediated responses ranged between a continuum from polyclonal to monoclonal (as seen in large granular lymphocytic leukemia). During a median observation period of 40 months, patients received a median of two different therapies to achieve remission. Frequently used therapy included calcineurin-inhibitors with a steroid taper yielding a first-line overall response rate of 76% (53/70). Oral cyclophosphamide showed activity, albeit lower than that produced by cyclosporine. Intravenous immunoglobulins were effective both in parvovirus patients and in hypogammaglobulinemia cases. In salvage settings, alemtuzumab is active, particularly in large granular lymphocytic leukemia-associated cases. Other potentially useful salvage options include rituximab, anti-thymocyte globulin and bortezomib. The workup of acquired pure red cell aplasia should include investigations of common pathological associations. Most effective therapies are directed against T-cell-mediated immunity, and therapeutic choices need to account for associated conditions that may help in choosing alternative salvage agents, such as intravenous immunoglobulin, alemtuzumab and bortezomib.

Neutropenia in Patients with Common Variable Immunodeficiency: a Rare Event Associated with Severe Outcome

BACKGROUND

Common variable immunodeficiency (CVID) is characterized by infections and hypogammaglobulinemia. Neutropenia is rare during CVID.

METHODS

The French DEFI study enrolled patients with primary hypogammaglobulinemia. Patients with CVID and neutropenia were retrospectively analyzed.

RESULTS

Among 473 patients with CVID, 16 patients displayed neutropenia (lowest count [0-1400]*10⁶/L). Sex ratio (M/F) was 10/6. Five patients died during the follow-up (11 years) with an increased percentage of deaths compared to the whole DEFI group (31.3 vs 3.4%, P < 0.05). Neutropenia was diagnosed for 10 patients before 22 years old. The most frequent symptoms, except infections, were autoimmune cytopenia, i.e., thrombopenia or anemia (11/16). Ten patients were affected with lymphoproliferative diseases. Two patients were in the infection only group and the others belonged to one or several other CVID groups. The median level of IgG was 2.6 g/L [0.35-4.4]. Most patients presented increased numbers of CD21^low CD38^low B cell, as already described in CVID autoimmune cytopenia group. Neutropenia was considered autoimmune in 11 cases. NGS for 52 genes of interest was performed on 8 patients. No deleterious mutations were found in LRBA, CTLA4, and PIK3. More than one potentially damaging variant in other genes associated with CVID were present in most patients arguing for a multigene process.

CONCLUSION

Neutropenia is generally associated with another cytopenia and presumably of autoimmune origin during CVID. In the DEFI study, neutropenia is coupled with more severe clinical outcomes. It appears as an "alarm bell" considering patients' presentation and the high rate of deaths. Whole exome sequencing diagnosis should improve management.

Successful management of multilineage autoimmune cytopenia complicated with severe infection and deep vein thrombosis in a patient with Hodgkin lymphoma post-autologous hematopoietic stem cell transplantation

Autoimmune cytopenia (AIHA, AITP or AIN) were uncommon paraneoplastic manifestations of HL and have been recognized in patients after HSCT with dismal outcome. We presented a case of 16-yr-old male with Hodgkin's lymphoma who developed severe AIC involving all three cell lineages after autologus bone marrow transplantation. No disease relapse was noted. Treatments with steroid, IVIG and immunosuppresants were in vain and the disease course was complicated with sepsis and deep vein thrombosis. Rituximab was administered along with broad-spectrum antibiotics and low-molecular weight heparin. The condition became stable and pancytopenia recovered after four doses of rituximab treatment. Severe multi-lineage AIC post HSCT is usually refractory to first-line treatment and difficult to manage. Second-line treatment, such as rituximab, and dedicated care for pancytopenia-induced or treatment-related complications may provide a better outcome.

Severe chronic primary neutropenia in adults: report on a series of 108 patients

Severe CPN in adults is a benign entity without secondary myeloid malignancies. Neutrophil count at diagnosis is the only predictive factor of severe infections.

Thymoma with Concomitant Pure Red Cell Aplasia, Good's Syndrome and Myasthenia Gravis Responding to Rituximab

Thymomas are often associated with a variety of autoimmune diseases, mostly myasthenia gravis. The association of thymomas with both pure red cell aplasia (PRCA) and Good's syndrome is exceedingly rare. To the best of our knowledge, the combination of a thymoma with manifestations of myasthenia gravis, PRCA, and Good's syndrome, as in our case herein, has not been described before in the medical literature. We present a 90-year-old man initially diagnosed with an asymptomatic thymoma. Later, he developed generalized muscle weakness and was found to have severe anemia. He was diagnosed with PRCA, myasthenia gravis and Good's syndrome. He responded to rituximab with restoration of bone marrow erythroid maturation and stabilization of red blood cell counts.

Pure red cell aplasia complicating the course of long-standing mantle cell lymphoma

Pure red cell aplasia (PRCA) is a rare cause of severe hypoplastic anemia characterized by profound depletion of erythroid precursors. Although PRCA may be associated with lymphoproliferative diseases, it has never been described in mantle cell lymphoma (MCL). We report what to our knowledge is the first case of a patient with indolent, non-nodal MCL complicated by PRCA. The patient presented with severe hypoproliferative anemia in the setting of a long-standing diagnosis of B-cell chronic lymphocytic leukemia. Bone marrow studies revealed the complete absence of erythroid progenitors. Cyclin D1 positivity on immunohistochemistry, confirmed by a positive FISH for t(11;14) (q13;q32), established the final diagnosis of MCL in conjunction with PRCA. Rituximab monotherapy led to rapid remission of splenomegaly and the leukemic picture, but the patient achieved transfusion independency only with subsequent administration of cyclosporine-A, and remained so during the subsequent 15 months despite the gradual disease recurrence.

Autoimmune neutropenia

Autoimmune neutropenia (AIN) is a rare entity caused by antibodies directed against neutrophil-specific antigens. It includes primary and secondary autoimmune neutropenia. Acute autoimmune neutropenia can be related to drug-induced mechanism or viral infections. Chronic autoimmune neutropenias occur in the context of autoimmune diseases, hematological malignancies, such as large granular lymphocyte leukemia, primary immune deficiency syndromes or solid tumors. The therapeutic management depends on the etiology. Granulocyte growth factor is the main therapeutic option, raising the question of their long-term utilization safety. Corticosteroids or immunosuppressive therapy are indicated in infection-related AIN or in case of symptomatic autoimmune disease or LGL leukemia.

Autoimmune cytopenias in chronic lymphocytic leukemia, facts and myths

CLL has been defined as presence of more than 5000 small mature appearing monoclonal B lymphocytes with a specific immunophenotype in peripheral blood. It is a well-known fact that CLL is associated with autoimmune cytopenias. CLL cells are CD5(+) B lymphocytes, and usually are not the "guilty" cells which produce autoantibodies. T cell defect is another characteristic of CLL and the total number of T cells is increased, and there is inversion of the CD4/CD8 ratio. Autoimmune hemolytic anemia (AIHA) is the most common autoimmune complication of CLL and has been reported in 10-25% of CLL patients. However, the stage-adjusted estimated rate of AIHA in CLL is about 5%. Conversely, CLL is three times more common in patients who present with AIHA. Direct agglutinin test (DAT) is positive in 7-14% of CLL patients but AIHA may also occur in DAT negative patients. Autoimmune thrombocytopenia (AIT) is the second most common complication of CLL and has been reported in 2-3% of patients. DAT is positive in AIT but presence of antiplatelet antibodies is neither diagnostic nor reliable. Autoimmune neutropenia (AIN) and pure red cell aplasia (PRCA) are very rare complications of CLL and like other autoimmune complications of CLL may occur at any clinical stage. It is believed that most case reports of AIN and PRCA in CLL actually belong to large granular lymphocytic leukemia (LGL). Non-hematologic autoimmune complications of CLL including cold agglutinin disease (CAD), paraneoplastic pemphigus (PNP), acquired angioedema, and anti-myelin associated globulin are rare. Before starting any treatment, clinicians should distinguish between autoimmune cytopenias and massive bone marrow infiltration since autoimmune complications of CLL are not necessarily equal to advanced disease with poor prognosis. According to IWCLL guideline, steroids are the mainstay of treatment of simple autoimmunity. Intravenous immunoglobulin (IVIg), cyclosporine, and rituximab are used in complex, steroid refractory cases. Monotherapy with purine analogues and alkylating agents should be avoided as they may increase CLL associated autoimmune complications.

Atypical Pneumocystis jiroveci pneumonia with multiple nodular granulomas after rituximab for refractory nephrotic syndrome

BACKGROUND

Rituximab, an anti-CD20 antibody that targets B cells, is a promising agent against steroid-dependent and steroid-resistant nephrotic syndrome in children.

CASE-DIAGNOSIS/TREATMENT

We report a 3-year-old boy who presented with atypical Pneumocystis jiroveci pneumonia (PCP) following administration of rituximab for refractory nephrotic syndrome. He had received cyclosporine and daily prednisolone for over 1 year. Following rituximab therapy, a hazy shadow was observed on his chest X-ray. Chest-computed tomography revealed multiple nodular lesions in bilateral lungs, although his clinical symptoms were subtle. PCR analysis demonstrated the presence of Pneumocystis DNA in his bronchoalveolar lavage. Lung wedge resection of the nodular lesion exhibited granulomas containing a few cysts of P. jiroveci that primarily consisted of T cells and histiocytes and lacked B cells. A deficiency of B cells following rituximab treatment suggests a dramatic effect on the immune response and, therefore, could result in granulomatous PCP. Nodular granulomatous lesions of PCP comprise an emerging concept previously reported in adults with hematological disease, bone marrow transplant, or treatment with rituximab. We report the first pediatric case of nodular PCP. Granulomatous PCP can be life-threatening. Moreover, bronchoalveolar lavage often fails to demonstrate the presence of P. jiroveci DNA. Wedge biopsy is warranted for definitive diagnosis. Our patient fully recovered with sulfamethoxazole/trimethoprim treatment because of early detection.

CONCLUSIONS

The indication of rituximab for refractory nephrotic syndrome has increased recently. Therefore, recognition of the risk of atypical PCP is important. Our findings suggest that PCP prophylaxis should be considered following rituximab therapy.

Adjuvant Chemotherapy for Breast Cancer in a Patient with Primary Autoimmune Neutropenia

We report an extremely rare and complex case of a 44-year-old woman diagnosed with an early stage triple negative breast cancer in the setting of primary autoimmune neutropenia with a pre-existing severe neutropenia. This case-report demonstrates that adjuvant chemotherapy for breast cancer can be administered in a patient with severe neutropenia. The management is however complicated and requires careful monitoring of side-effects related to both chemotherapy and treatment of autoimmune neutropenia. The role of chemotherapy in the treatment of triple negative breast cancer, the approach to autoimmune neutropenia and potential interactions are reviewed. To our knowledge, this is the first case reporting on the use of chemotherapy in a patient with severe pre-existing primary autoimmune neutropenia.

Glycosphingolipids mediate pneumocystis cell wall β-glucan activation of the IL-23/IL-17 axis in human dendritic cells

Pneumocystis species are opportunistic fungal organisms that cause severe pneumonia in immune-compromised hosts, with resultant high morbidity and mortality. Recent work indicates that IL-17 responses are important components of host defense against fungal pathogens. In the present study, we demonstrate that cell-surface β-glucan components of Pneumocystis (PCBG) stimulate human dendritic cells (DCs) to secrete IL-23 and IL-6. These cytokines are well established to stimulate a T helper-17 (Th17) phenotype. Accordingly, we further observe that PCBG-stimulated human DCs interact with lymphocytes to drive the secretion of IL-17 and IL-22, both Th17-produced cytokines. The activation of DCs was shown to involve the dectin-1 receptor with a downstream activation of the Syk kinase and subsequent translocation of both the canonical and noncanonical components of the NF-κB transcription factor family. Finally, we demonstrate that glycosphingolipid-rich microdomains of the plasma membrane participate in the activation of DCs by PCBG through the accumulation of lactosylceramide at the cell surface during stimulation with PCBG. These data strongly support the idea that the β-glucan surface components of Pneumocystis drive the activation of the IL-23/IL-17 axis during this infection, through a glycosphingolipid-initiated mechanism.

A case of pure red cell aplasia and immune thrombocytopenia complicating systemic lupus erythematosus: response to rituximab and cyclophosphamide

Pure red cell aplasia (PRCA) is a recognized but rare complication of systemic lupus erythematosus (SLE) and is characterized by the near absence of red blood cell precursors in the bone marrow but with normal megakaryocyte and granulocytes. We report a novel case of acquired PRCA occurring simultaneously with immune thrombocytopenia in the context of active SLE. Both syndromes were refractory to conventional treatment but responded to rituximab and cyclophosphamide.

Anti-CD20 monoclonal antibodies and their use in adult autoimmune hematological disorders

Autoimmune hematological disorders encompass a broad group of hematological conditions characterized by the loss of self-tolerance to a variety of antigens. Despite good response to first-line therapy in the majority of patients, relapses are common, necessitating new and safe therapeutic options. The anti-CD20 monoclonal antibody rituximab has led to substantial improvement in the treatment of malignant and immune-mediated disorders involving B cells. Although experience with rituximab in immune-mediated hematological disorders is rarely supported by randomized trials, there is now substantial experience with rituximab suggesting that anti-CD20 therapy is an effective and well-tolerated alternative to immunosuppressive therapy in these disorders. However, caution is needed based on recent reports describing-sometimes severe-rituximab-related complications.

Update on the diagnosis and treatment of Pneumocystis pneumonia

Pneumocystis is an opportunistic fungal pathogen that causes an often-lethal pneumonia in immunocompromised hosts. Although the organism was discovered in the early 1900s, the first cases of Pneumocystis pneumonia in humans were initially recognized in Central Europe after the Second World War in premature and malnourished infants. This unusual lung infection was known as plasma cellular interstitial pneumonitis of the newborn, and was characterized by severe respiratory distress and cyanosis with little or no fever and no pathognomic physical signs. At that time, only anecdotal cases were reported in adults and usually these patients had a baseline malignancy that led to a malnourished state. In the 1960-1970s additional cases were described in adults and children with hematological malignancies, but Pneumocystis pneumonia was still considered a rare disease. However, in the 1980s, with the onset of the HIV epidemic, Pneumocystis prevalence increased dramatically and became widely recognized as an opportunistic infection that caused potentially life-treating pneumonia in patients with impaired immunity. During this time period, prophylaxis against this organism was more generally instituted in high-risk patients. In the 1990s, with widespread use of prophylaxis and the initiation of highly active antiretroviral therapy (HAART) in the treatment of HIV-infected patients, the number of cases in this specific population decreased. However, Pneumocystis pneumonia still remains an important cause of severe pneumonia in patients with HIV infection and is still considered a principal AIDS-defining illness. Despite the decreased number of cases among HIV-infected patients over the past decade, Pneumocystis pneumonia continues to be a serious problem in immunodeficient patients with other immunosuppressive conditions. This is mostly due to increased use of immunosuppressive medications to treat patients with autoimmune diseases, following bone marrow and solid organ transplantation, and in patients with hematological and solid malignancies. Patients with hematologic disorders and solid organ and hematopoietic stem cell transplantation are currently the most vulnerable groups at risk for developing this infection. However, any patient with an impaired immunity, such as those receiving moderate doses of oral steroids for greater than 4 weeks or those receiving other immunosuppressive medications are at also at significant risk.

Rituximab-associated infections

After more than 10 years of use, rituximab has proven to be remarkably safe. However, accumulated evidence now suggests that under some circumstances it may significantly increase the risk of infections. This risk is difficult to quantify because of confounding factors (namely, concomitant use of immunosuppressive or chemotherapeutic agents and underlying conditions), as well as under-reporting. Increased number of infections has been documented in patients treated with maintenance rituximab for low-grade lymphoma and in patients with concomitant severe immunodeficiency, whether caused by human immunodeficiency virus (HIV) infection or immunosuppressive agents like fludarabine. From the practical standpoint, the most important infection is hepatitis B reactivation, which may be delayed and result in fulminant liver failure and death. Special care should be placed on screening for hepatitis B virus (HBV) and preemptive antiviral treatment. Some investigators have reported an increase in Pneumocystis pneumonia. Finally, there is increasing evidence of a possible association with progressive multifocal leukoencephalopathy (PML), a lethal encephalitis caused by the polyomavirus JC. This review enumerates the described infectious complications, summarizes the possible underlying mechanisms of the increased risk, and makes recommendations regarding prevention, diagnosis and management.

Pneumocystis pneumonia: current concepts in pathogenesis, diagnosis, and treatment

Pneumocystis pneumonia (PCP) is an infection of the lungs caused by the opportunistic fungal genus Pneumocystis. In humans, PCP is a serious and potentially life-threatening infection occurring in immunocompromised individuals, particularly those who have AIDS, or following immune suppression from malignancy, organ transplantation, or therapies for inflammatory diseases. Several recent studies have contributed to understanding of the biology and pathogenesis of the organism yielding new diagnostic approaches and therapeutic targets. Although trimethoprim-sulfamethoxazole remains the mainstay of prophylaxis and treatment, ongoing concerns for emerging Pneumocystis resistance supports the continuing investigation for novel therapeutic agents.

Advances in the biology, pathogenesis and identification of Pneumocystis pneumonia

PURPOSE OF REVIEW

Pneumocystis pneumonia remains the most prevalent opportunistic infection in patients with AIDS. It is also a common devastating infection in patients with other causes of altered immunity. Though scientific study of this fungal pathogen is challenging given the inability to propagate the organism outside of the host lung, studies utilizing advanced molecular techniques and genomic analysis have broadened our understanding of the epidemiology and pathogenesis of Pneumocystis and will be described herein.

RECENT FINDINGS

Results from advanced molecular techniques suggest that Pneumocystis organisms not only cause infection in patients with impaired immunity but also colonize mammals with normal immune systems. Advanced technology has also identified acquired Pneumocystis genetic mutations that confer resistance to currently utilized therapeutics. Though not yet widely utilized in clinical medicine, advanced polymerase chain reaction techniques improve the diagnostic yield of respiratory specimen analysis. Preliminary results from serum beta-glucan testing suggest that a noninvasive marker of Pneumocystis pneumonia infection and response to therapy may be on the horizon.

SUMMARY

Recent scientific advances suggest opportunities for improving the diagnosis and treatment surveillance of Pneumocystis pneumonia. Further investigations are necessary to define the optimal characteristics of these laboratory tests and to develop therapeutics directed at novel Pneumocystis genomic targets.

Intrinsic and treatment-related immune alterations in chronic lymphocytic leukaemia and their impact for clinical practice

BACKGROUND

Chronic lymphocytic leukaemia patients harbour important impairments in both their cellular- and humoral-mediated immunity, which accounts for their notorious susceptibility to a multitude of infections and various autoimmune cytopenias. It has also been shown that the rate of second cancers is increased in chronic lymphocytic leukaemia.

OBJECTIVE

The aim of this study was to review the immune alterations in untreated and treated chronic lymphocytic leukaemia and define their impact for clinical practice.

METHODS

The author gives a comprehensive review of the most relevant preclinical and clinical studies pertaining to various immune abnormalities and infectious complications in both untreated and treated chronic lymphocytic leukaemia. Landmark clinical trials involving the contemporary chronic lymphocytic leukaemia chemo- and immunotherapies, alone or in combination, as well as the main epidemiological studies establishing the increased rate of second cancers in chronic lymphocytic leukaemia are also discussed.

RESULTS/CONCLUSIONS

Iatrogenic immunosuppression in chronic lymphocytic leukaemia alters the pattern of opportunistic infections, can cause autoimmune cytopenias and might further increase the rate of second malignancies in patients whose disease already places them at a greater risk. Careful consideration of existing risk factors in chronic lymphocytic leukaemia could establish the optimal screening and follow-up schedule for chronic lymphocytic leukaemia patients as its therapeutics evolves.

Acquired pure red cell aplasia: updated review of treatment

Pure red cell aplasia (PRCA) is a syndrome characterized by a severe normocytic anaemia, reticulocytopenia, and absence of erythroblasts from an otherwise normal bone marrow. Primary PRCA, or secondary PRCA which has not responded to treatment of the underlying disease, is treated as an immunologically-mediated disease. Although vigorous immunosuppressive treatments induce and maintain remissions in a majority of patients, they carry an increased risk of serious complications. Corticosteroids were used in the treatment of PRCA and this has been considered the treatment of first choice although relapse is not uncommon. Cyclosporine A (CsA) has become established as one of the leading drugs for treatment of PRCA. However, common concerns have been the number of patients treated with CsA who achieve sustained remissions and the number that relapse. This article reviews the current status of CsA therapy and compares it to other treatments for diverse PRCAs.

Successful treatment of refractory immune hemolysis following unrelated cord blood transplant with Campath-1H

Immune-mediated hemolytic anemia is a well-recognized complication of hematopoietic stem cell transplantation. We report on a 6-year-old boy with X-linked adrenoleukodystrophy who developed severe delayed alloimmune hemolytic anemia associated with immune-mediated neutropenia and thrombocytopenia following major ABO incompatible unrelated cord blood transplantation. The patient's cytopenias were refractory to treatment with corticosteroids, cyclosporine, intravenous immune globulin, rituximab, and pentostatin. After one course of Campath-1H his hematologic parameters normalized, suggesting that the compound may be an effective therapy for complex immunohematologic disorders complicating hematopoietic stem cell transplantation. The case also emphasizes the importance of T-cells in transplant associated immune cytopenias.

Late onset of autoimmune hemolytic anemia and pure red cell aplasia after allogeneic hematopoietic stem cell transplantation using in vivo alemtuzumab

Hemolytic anemia and pure red cell aplasia (PRCA) after allogeneic hematopoietic stem cell transplantation (HSCT) have been reported to be mainly related to ABO-incompatibility between donor and recipient. Autoimmune hemolytic anemia (AIHA) without ABO-incompatibility has been also reported after allogeneic HSCT, especially with T-cell depletion. However, optimal management of AIHA or PRCA remains unclear. A 54-year-old male with myelodysplastic syndrome (MDS) underwent haploidentical human leukocyte antigen-mismatched HSCT using in vivo alemtuzumab and developed AIHA and PRCA simultaneously 15 months after transplantation, following the administration of cidofovir and probenecid for persistent cytomegalovirus (CMV) antigenemia and retinitis. AIHA was successfully treated with rituximab, and subsequently PRCA with cyclosporine without relapse of MDS or recurrence of CMV infection. The clinical course suggested that AIHA was mainly caused by humoral immune response, while PRCA was mainly caused by cell-mediated immune response in this patient, although these immune responses might be related to each other.

Disease-Specific Complications of Chronic Lymphocytic Leukemia

The majority of disease-specific complications in chronic lymphocytic leukemia (CLL), notably infection and autoimmunity, relate to the underlying alterations in immune function. Both cellular and humoral immunity are impaired with qualitative and quantitative defects in B cells, T cells, NK cells, neutrophils and the monocyte/macrophage lineage. Virtually all patients have reduced immunoglobulin levels, even in early stages, and this is associated with an increased frequency and severity of infection. Although prophylactic intravenous immunoglobulin may be of clinical benefit in selected patients, it does not reduce mortality and is certainly not cost-effective. Autoimmune complications occur in up to a quarter of CLL patients and predominantly target blood cells. Autoimmune hemolytic anemia (AHA) is the most common manifestation; immune thrombocytopenia, pure red cell aplasia and autoimmune neutropenia are less common, while non-hematological autoimmunity is rare. The UK CLL4 trial is the largest prospective trial in CLL to examine the significance of both a positive direct antiglobulin test (DAT) and AHA. The study confirmed the usefulness of the DAT in predicting the development of AHA or not, demonstrated that AHA occurred more frequently in patients receiving treatment with chlorambucil or fludarabine alone compared with the combination of fludarabine and cyclophosphamide, and showed that a positive DAT and the development of AHA were poor prognostic markers. Management of CLL-associated autoimmunity rests on good supportive care and the use of immunosuppressive therapies such as steroids and cyclosporine. Splenectomy remains useful, and monoclonal antibodies (rituximab and alemtuzumab) have given promising results.