Reversible monoclonal lymphadenopathy in autoimmune lymphoproliferative syndrome with functional FAS (CD95/APO-1) deficiency

An unusual self-limited clonal Mott cell proliferation with lymphoplasmacytic lymphoma-like features in a child with the Wiskott-Aldrich syndrome and Von Recklinghausen's neurofibromatosis

Patients with the Wiskott-Aldrich syndrome are at high risk for development of lymphomas, which are predominantly extranodal and of the immunoblastic type. We present a case of a self-limited lymphoproliferation with features of lymphoplasmacytic lymphoma arising in a patient with the Wiskott-Aldrich syndrome. The patient also had stigmata of von Recklinghausen's neurofibromatosis. The tumor was composed of CD138+, IgGkappa+, CD20-, PAX-5- Mott cells and CD5-, CD10-, CD19+, CD20+, CD43- small lymphoid B-cells that partially expressed CD23. The lymphadenopathy spontaneously resolved after a period of less than a year, and the patient had remained free of detectable lymphoproliferation for almost 4 years. He then developed Burkitt's lymphoma of the left parapharyngeal space. It is remarkable that both known lymphoproliferations with features of lymphoplasmatic lymphoma arising in patients with the Wiskott-Aldrich syndrome, this one and the previously described one, have spontaneously resolved. This observation is truly intriguing and requires further clinico-pathologic studies.

Analysis of single nucleotide polymorphisms in the FAS and CTLA-4 genes of peripheral T-cell lymphomas

Angioimmunoblastic T-cell lymphoma (AILT) represents a subset of T-cell lymphomas but resembles an autoimmune disease in many of its clinical aspects. Despite the phenotype of effector T-cells and high expression of FAS and CTLA-4 receptor molecules, tumor cells fail to undergo apoptosis. We investigated single nucleotide polymorphisms (SNPs) of the FAS and CTLA-4 genes in 94 peripheral T-cell lymphomas. Although allelic frequencies of some FAS SNPs were enriched in AILT cases, none of these occurred at a different frequency compared to healthy individuals. Therefore, SNPs in these genes are not associated with the apoptotic defect and autoimmune phenomena in AILT.

Development of granulomatous common variable immunodeficiency subsequent to infection with Toxoplasma gondii

Common variable immunodeficiency (CVID) is a heterogeneous immunodeficiency that is accompanied by granulomatous lesions in 5-10% of cases. Why some patients develop granulomatous disease remains unclear. Here we describe a 12-year-old previously healthy girl who presented with pancytopenia and granulomatous lymphoproliferation subsequent to infection with Toxoplasma gondii. Loosely arranged non-fibrosing granulomas were observed in the liver, lymph nodes and lung, but no Toxoplasma tachyzoites could be demonstrated and polymerase chain reaction (PCR) and culture were negative for Toxoplasma and a wide range of other pathogens. While the patient had a normal peripheral B cell status at presentation, the development of CVID could be observed during the following months, leading to a loss of memory B cells. This was accompanied by an increasingly activated CD4(+) T cell compartment and high serum levels of angiotensin-converting enzyme (ACE), tumour necrosis factor (TNF) and sCD25. Steroid therapy reduced pancytopenia, granulomatous lymphoproliferation and cytokine elevations, but did not improve the B cell status. This is the first report of an association of Toxoplasma infection with granulomatous CVID and provides one of the rare examples where the onset of CVID could be documented subsequent to an infectious disease.

Autoimmune lymphoproliferative syndrome: etiology, diagnosis, and management

Autoimmune lymphoproliferative syndrome (ALPS) is a childhood disorder characterized by chronic, nonmalignant lymphoproliferation and autoimmunity, most commonly involving cells of hematopoietic origin. Mutations of the tumor necrosis factor receptor super family member 6 (TNFRSF6) gene, coding for the apoptosis-inducing protein Fas (Apo-1, CD95) are involved in the physiopathology of the syndrome, although the complete mechanism by which the syndrome is caused has not yet been unraveled. Although the syndrome has a benign nature, life-threatening complications can demand treatment. Treatment schedules, including corticosteroids, low doses of chemotherapy, granulocyte colony stimulating factor, or splenectomy, have varying results. Treatment with the antimalarial drug pyrimethamine/sulfadoxine (25/500mg per tablet) seems to be a new, well tolerated, and efficient approach, although larger studies will have to demonstrate the true value of this drug in patients with ALPS.

B-Cell lymphoproliferative disorder not associated with Epstein-Barr Virus in a child with relapsed acute lymphoblastic leukemia

Lymphoproliferative disorder (LPD) is described in only a few children receiving chemotherapy for cancer. In all of them, an association between LPD and EBV (Epstein-Barr Virus) was found. We report on a patient who developed LPD not associated with EBV while receiving chemotherapy for relapsed acute lymphoblastic leukemia (ALL). Despite discontinuation of chemotherapy, administration of intravenous immunoglobulins and surgery the patient died. Growing experience with this disorder may allow better treatment options in the future and will show whether LPD not associated with EBV requires different therapeutic strategies.

Trisomy 4 pter-q12 and monosomy of chromosome 13 pter-q12 in a male with deficiency of all blood lymphocyte populations

A six-year-old male presented with multiple congenital anomalies, mental retardation, developmental delay, and an increased frequency of upper and lower respiratory infections and deficiency of all blood lymphocyte populations. Chromosome analysis showed an unbalanced translocation involving chromosomes 4 and 13, leading to partial trisomy for 4pter-q12 and partial monosomy for 13pter-q13 [karyotype, 46,XY,+der(4)t(4;13)(q12;q12),-13)]. The mother is the carrier of a balanced translocation involving chromosomes 4 and 13. The translocation is known to be segregating for three generations in this family. The child was found to have deficiency of all blood lymphocyte populations, but other hemopoietic lineages appeared to be normal. In addition, his fresh T cells were principally CD45RA+, CD62L+, and deficient in the Fas receptor. This deficiency of all blood lymphocyte populations may be due to an overdose of a gene or genes located in the region of chromosome 4 or a partial deficiency of a gene or genes in the region of chromosome 13 that regulate the development of the lymphocyte lineage. Since the mother contributed two copies of chromosomal region 4pter-q12 and no copy of 13pter-q12, the deficiency of all blood lymphocyte populations in our patient may be the result of either uniparental disomy or imprinting. A maternal granduncle with dissimilar dysmorphic features was not lymphopenic but was neutropenic.

Autoimmune lymphoproliferative syndrome type III, an indefinite disorder

Autoimmune Lymphoproliferative Syndrome (ALPS) is a childhood disorder characterized by chronic nonmalignant lymphoproliferation and autoimmunity. Although the pathogenesis is not fully understood, deficient Fas mediated apoptosis appears to be an important factor. This deficiency can be caused by a mutation of the APTI gene (ALPS type Ia), of the FasL gene (ALPS type Ib), or of the Caspase-10 gene (ALPS type II). In one sub population of patients, no mutations have been identified as yet (ALPS type III). According to published data, the latter group is much smaller than the group of patients with ALPS type Ia. However, because of the variability of the clinical presentation and the absence of a known genetic defect, this disease is difficult to diagnose, the more so as few data have been reported on these patients. Thus, ALPS type III could be more common than believed until now. In this review we provide evidence for this hypothesis.

Autoimmune lymphoproliferative syndrome type III: an indefinite disorder

Autoimmune Lymphoproliferative Syndrome (ALPS) is a childhood disorder characterized by chronic nonmalignant lymphoproliferation and autoimmunity. Although the pathogenesis is not fully understood, deficient Fas mediated apoptosis appears to be an important factor. This deficiency can be caused by a mutation of the APT1 gene (ALPS type Ia), of the FasL gene (ALPS type Ib), or of the Caspase-10 gene (ALPS type II). In one sub population of patients, no mutations have been identified as yet (ALPS type III). According to published data, the latter group is much smaller than the group of patients with ALPS type Ia. However, because of the variability of the clinical presentation and the absence of a known genetic defect, this disease is difficult to diagnose, the more so as few data have been reported on these patients. Thus, ALPS type III could be more common than believed until now. In this review we provide evidence for this hypothesis.

Autoimmune lymphoproliferative syndrome. A human disorder of abnormal lymphocyte survival

The importance of Fas in the homeostatic balance between lymphocyte survival and death is underscored by the three main consequences of defective Fas-mediated apoptosis, as experienced by patients with ALPS: (1) abnormal accumulation of lymphocytes results in lymphadenopathy, hepatosplenomegaly, and hypersplenism; (2) failure of removal of potentially autoreactive lymphocytes, a process normally used to eliminate lymphocytes that have escaped negative selection in the thymus and bone marrow (see article by Fleisher and Blessing, p. 1197), is associated with the appearance of autoimmune manifestations; and (3) inappropriate survival of lymphocytes may lead to the development of malignancies. As with other "experiments of nature," the many aspects of ALPS have provided valuable new insights into the immune system and the importance of a proper balance between life and death of lymphocytes. ALPS is an example of how a mouse disease model was applied directly to the identification of the molecular basis and the understanding of a remarkable disease in humans. It is also an example of clinical observations being linked to basic scientific data to unlock the underlying defect(s) causing a disease. Despite the difficulty in fully understanding the complex nature of the clinical course, the immunologic abnormalities, and the genetic aspects of ALPS, the accumulated experience in diagnosis, treatment, and follow-up of patients and relatives has generated a "road map" that can be used as a guide for their care. As examples, the appreciation that manifestations of lymphoproliferation usually subside over time has allowed a "wait-and-see" approach in many patients who might previously have been treated aggressively. The appreciation that these patients are at increased risk for malignancies has mandated the adoption of careful and lifelong follow-up. Future efforts directed at careful clinical follow-up and scientific investigation are required to learn more about the incidence and natural history of ALPS, therapeutic interventions directed at altering the consequences of TNFRSF6 mutations, and the identification of other genetic and environmental factors that may have a role in the pathogenesis of ALPS.

Atypical Lymphoproliferative Diseases

This review addresses the clinical presentation, pathology, and therapy of several uncommon lymphoid proliferations. Because these lymphoproliferations span the characteristics of reactive polymorphous proliferations to clonal malignant neoplasms, they are often difficult to diagnose and treat effectively.

In Section I, Dr. Greiner describes the pathology of the spectrum of atypical lymphoid disorders including Castleman's disease, angioimmunoblastic lymphadenopathy, lymphadenopathy in autoimmune diseases, posttransplant lymphoproliferative disorders, and X-linked lymphoproliferative disorder. The relationship to Epstein-Barr virus (EBV) and human herpsesvirus-8 (HHV-8) is discussed, and molecular diagnostic assays and principles for obtaining proper diagnostic evaluation are emphasized.

In Section II, Dr. Armitage presents a practical approach to the management of Castleman's disease. The discussion includes the importance of confirmation of the histological diagnosis and careful staging evaluation, therapeutic options, and the increased risks for infection and lymphoma. The appropriate roles of surgical excision, corticosteroids, and combination chemotherapy are addressed along with alternative strategies such as anti-interleukin-6 and bone marrow transplantation.

In Section III, Dr. Gross reviews the treatment of EBV-associated lymphoproliferative disorders in primary immunodeficiencies and in post-transplant patients. He gives an update on the recent molecular discoveries in X-linked lymphoproliferative disorder. Preliminary results of a phase II trial of low-dose cyclophosphamide in posttransplant lymphoproliferative disorders and the use of GM-CSF as preemptive therapy are presented.

Atypical Lymphoproliferative Diseases

This review addresses the clinical presentation, pathology, and therapy of several uncommon lymphoid proliferations. Because these lymphoproliferations span the characteristics of reactive polymorphous proliferations to clonal malignant neoplasms, they are often difficult to diagnose and treat effectively.

In Section I, Dr. Greiner describes the pathology of the spectrum of atypical lymphoid disorders including Castleman's disease, angioimmunoblastic lymphadenopathy, lymphadenopathy in autoimmune diseases, posttransplant lymphoproliferative disorders, and X-linked lymphoproliferative disorder. The relationship to Epstein-Barr virus (EBV) and human herpsesvirus-8 (HHV-8) is discussed, and molecular diagnostic assays and principles for obtaining proper diagnostic evaluation are emphasized.

In Section II, Dr. Armitage presents a practical approach to the management of Castleman's disease. The discussion includes the importance of confirmation of the histological diagnosis and careful staging evaluation, therapeutic options, and the increased risks for infection and lymphoma. The appropriate roles of surgical excision, corticosteroids, and combination chemotherapy are addressed along with alternative strategies such as anti-interleukin-6 and bone marrow transplantation.

In Section III, Dr. Gross reviews the treatment of EBV-associated lymphoproliferative disorders in primary immunodeficiencies and in post-transplant patients. He gives an update on the recent molecular discoveries in X-linked lymphoproliferative disorder. Preliminary results of a phase II trial of low-dose cyclophosphamide in posttransplant lymphoproliferative disorders and the use of GM-CSF as preemptive therapy are presented.