Complete Multilineage CD4 Expression Defect Associated With Warts Due to an Inherited Homozygous CD4 Gene Mutation.

Idiopathic T-CD4 lymphocytopenia (ICL) is a rare and heterogeneous syndrome characterized by opportunistic infections due to reduced CD4 T-lymphocytes (<300 cells/µl or <20% T-cells) in the absence of HIV infection and other primary causes of lymphopenia. Molecular testing of ICL has revealed defects in genes not specific to CD4 T-cells, with pleiotropic effects on other cell types. Here we report for the first time an absolute CD4 lymphocytopenia (<0.01 CD4+ T-cells/µl) due to an autosomal recessive CD4 gene mutation that completely abrogates CD4 protein expression on the surface membrane of T-cells, monocytes, and dendritic cells. A 45-year-old female born to consanguineous parents consulted because of exuberant, relapsing, and treatment-refractory warts on her hands and feet since the age of 10 years, in the absence of other recurrent infections or symptoms. Serological studies were negative for severe infections, including HIV 1/2, HTLV-1, and syphilis, but positive for CMV and EBV. Blood analysis showed the absence of CD4+ T-cells (<0.01%) with repeatedly increased counts of B-cells, naïve CD8+ T-lymphocytes, and particularly, CD4/CD8 double-negative (DN) TCRαß+ TCRγδ- T-cells (30% of T-cells; 400 cells/µl). Flow cytometric staining of CD4 using monoclonal antibodies directed against five different epitopes, located in two different domains of the protein, confirmed no cell surface membrane or intracytoplasmic expression of CD4 on T-cells, monocytes, and dendritic cells but normal soluble CD4 plasma levels. DN T-cells showed a phenotypic and functional profile similar to normal CD4+ T-cells as regards expression of maturation markers, T-helper and T-regulatory chemokine receptors, TCRvß repertoire, and in vitro cytokine production against polyclonal and antigen-specific stimuli. Sequencing of the CD4 gene revealed a homozygous (splicing) mutation affecting the last bp on intron 7-8, leading to deletion of the juxtamembrane and intracellular domains of the protein and complete abrogation of CD4 expression on the cell membrane. These findings support previous studies in CD4 KO mice suggesting that surrogate DN helper and regulatory T-cells capable of supporting antigen-specific immune responses are produced in the absence of CD4 signaling and point out the need for better understanding the role of CD4 on thymic selection and the immune response.

Idiopathic CD4 lymphopenia in a case of disseminated cryptococcosis with brain, vertebral spine and reproductive organ involvement.

Cryptococcosis is an opportunistic fungal infection commonly seen in HIV cases. We present a case of disseminated cryptococcosis with multiple non-continuous infective foci in a non-HIV, non-transplant case.

Idiopathic lymphocytopenia.

PURPOSE OF REVIEW: Idiopathic CD4⁺ lymphocytopenia (ICL) is defined by the reduction of the main lymphocyte subtype in peripheral blood and CD4⁺ T cells below 300/µl in the absence of any secondary known causes of lymphopenia, including viral causes. The present review aims to state the latest available data on clinical, pathological and therapeutic aspects related to ICL, published from 1990 to 2014. The last observed clinical presentation and complications of ICL patients are described. The latest findings and possible mechanisms involved in the development of ICL features are included in the present review; however, pathogenesis of ICL has remained mainly obscured. Finally, recent therapeutic efforts considered in ICL patients are discussed. RECENT FINDINGS: In spite of the serious complications ICL has on the patients' quality of life, data on clinical, etiopathological and therapeutic behavior for ICL are very limited. On one side, an abnormal blood cell count may be the sole presentation; however, occurrence of disseminated malignant tumors is not uncommon in patients. Recent findings highlight the role of cytokines, especially interleukin-2, on features such as phenotype severity and responsiveness of the condition to therapy. In addition, some studies have suggested that a defect in hematopoietic stem cells may be involved in disease progression, an idea that is supported by the success of bone marrow transplantation in acquiring persistent remissions in ICL patients. SUMMARY: ICL is a hematologic condition of increasing importance due to its diverse clinical and pathological spectrum. Molecular studies have shown the presence of mutations involved in lymphocyte development as potential factors that may contribute to ICL occurrence. ICL patients could present either with common infections or really serious malignant conditions. The role of cytokines, especially interleukin-2, has emerged as one of the main possible mechanisms involved in clinical and pathological behavior of ICL. Today, the main therapeutic approaches are controlling life-threatening infections and underlying disorders along with efforts to cure ICL through rising CD4⁺ cell counts using cytokine interventions and transplantation.

Primary Sjögren's syndrome and B-non-Hodgkin lymphoma: role of CD4+ T lymphocytopenia.

Primary Sjögren's syndrome (PSS) is associated with increased risk of lymphoproliferative malignancy, and B-cell non-Hodgkin lymphoma (B-NHL) is the most frequent type. To evaluate CD4+ T lymphocytes distributions in patients with (PSS) and the association of CD4+ T lymphocytopenia with the development of (B-NHL), this study included 8 (PSS) patients associated with B-NHL (group I), 50 (pSS) patients without B-NHL (group II), and 30 healthy volunteers who served as controls. The frequency of circulating CD4+ and CD8+ T lymphocytes distributions and CD4+/CD8+ T cell ratio was assessed using flow cytometry coulter EPICS-XL and compared between patients groups and controls. There was statistically significant CD4+ T lymphocytopenia in (PSS) patients with B-NHL than those without lymphoma and controls (P = 0.001). Moreover, a significant low CD4+/CD8+ T cell ratio 0.8 in group I than group II and controls (P = 0.001) was found. Significant positive correlations of CD4+ T lymphocytopenia with other risk factors (parotid swelling, vasculitis, rheumatoid factors, low complement, cryoglobulinemia) were detected. CD4+ T lymphocytopenia is associated with B-NHL developed in patients with PSS and can be considered as an important predictor of lymphoma.

Non-myeloablative hematopoietic stem cell transplantation in the treatment of severe idiopathic CD4+ lymphocytopenia.

A 40-year-old man with severe chronic idiopathic CD4+ lymphocytopenia complicated with opportunistic infections was successfully treated with non-myeloablative allogeneic hematopoietic stem cell transplantation. After conditioning with fludarabine plus low dose of total-body irradiation, CD34+ peripheral blood stem cells obtained by leukapheresis from his HLA-identical sister were infused. T cell and myeloid complete chimerism was achieved at day +28 and remained stable during the follow-up period. The patient did not develop infectious complications during the procedure. At 35 months of follow-up, his CD4+ T cell count was 1019 cells per microliter. Non-myeloablative allogeneic hematopoietic stem cell transplantation should be considered a treatment option for patients with severe forms of idiopathic CD4+ lymphocytopenia.

Progressive multifocal leukoencephalopathy in a patient with idiopathic CD4+ cells deficit.

Progressive multifocal leukoencephalopathy (PML) is a fatal neurological disease affecting the central nervous system. JC polyomavirus is the agent related to this disease. PML usually occurs in patients with HIV infection or other immunodeficiencies. We report a case of PML in a patient with idiopathic CD4+ cells deficit. The symptoms began with right arm hyposthenia followed by right hemiplegia. Blood analyses were normal, the only abnormal value was a marked decrease in CD4+ cells count with normal CD8+ cells. The magnetic resonance imaging (MRI) of the brain, showed multiple non-homogeneous lesions without enhancement in the left callous circumvolution and in the sub-cortical left frontal white matter. In the following two weeks, the patient had relevant progression in neurological deficits and a subsequent MRI demonstrated significant worsening. Because of the rapid clinical progression, we decided to start therapy with Cidofovir. The patient, after one month of admission, was slowly worsening in neurological functions.

EBV(+) B-cell lymphoproliferative disorder associated with subsequent development of Burkitt lymphoma in a patient with idiopathic CD4(+) T-lymphocytopenia.

We report here a case of idiopathic CD4(+) T-lymphocytopenia (ICL) associated with Epstein-Barr virus (EBV)(+) lymphoproliferative disorder (LPD) terminating in Burkitt lymphoma (BL). A 33-year-old Japanese male was admitted to the hospital showing severe CD4(+) lymphocytopenia and neutropenia that was diagnosed as ICL in 1993. Twenty months after the onset of disease, right cervical lymphadenopathy was detected. Biopsy of the specimen showed reactive lymph node hyperplasia and interfollicular B-cell hyperplasia. Ninety-one months later, polypoid tumors were resected from the bilateral nasal cavities and were diagnosed as BL. Immunohistological studies suggested the reactive nature of the initial lymph node biopsy specimen. Polymerase chain reaction (PCR) analyses of immunoglobulin heavy-chain gene (IgH) demonstrated a polyclonal pattern in the initial lymph node lesion. However, the subsequent BL demonstrated a clonal band in the PCR assay for the IgH gene. As demonstrated in human immunodeficiency virus (HIV)-patients, clonal expansion of EBV infected B-cells in the initial lymph node lesion may progress to BL in this patient. The present case did not associate with severe opportunistic infections during the course of disease. EBV(+) BL may be the first manifestation of severe immunodeficiency of the ICL in this patient.

Progressive multifocal leukoencephalopathy and CD4+ T-lymphocytopenia in a patient with Sjögren syndrome.

We report progressive multifocal leukoencephalopathy (PML) and CD4+ T-lymphocytopenia in a 71-year-old man with Sjögren syndrome (SjS). The patient was admitted to our hospital because of progressive dementia and gait disturbance. T2-weighted MR images showed high-intensity lesions in his left frontal white matter thalamus, cerebellum and brainstem. A pathological diagnosis of PML was made by brain biopsy. SjS is frequently accompanied with immunological complications; however, there are few reports on PML in patients with SjS. Recently, isolated CD4+ T-lymphocytopenia is reported to be one of the based immunological conditions associated with the development of PML. In the present case, CD4+ T-lymphocytopenia was also observed on admission, which is also associated with SjS.

Idiopathic CD4+ T lymphocytopenia is associated with increases in immature/transitional B cells and serum levels of IL-7.

Idiopathic CD4+ T lymphocytopenia (ICL) is a rare heterogeneous disorder defined by CD4+ T-cell counts below 300 cells/muL in the absence of human immunodeficiency virus (HIV) infection or other known immune deficiency disorders. Here, we report the expansion of immature/transitional B cells in patients with ICL, which is associated with elevated serum levels of IL-7. Both the percentage of immature/transitional B cells and levels of IL-7 were inversely correlated with levels of CD4+ T-cell counts and directly correlated to each other. Further analyses of B cells indicated that, in contrast to the activating effects of HIV disease on mature B cells, the expansion of immature/transitional B cells in patients with ICL occurred at the expense of memory B cells. These findings extend previous reports on primary immunodeficiencies as well as HIV disease by suggesting that CD4+ T-cell lymphopenia has an impact on human B-cell development either directly or indirectly via the associated elevation of IL-7 levels.

Prevention of spontaneous arthritis by inhibiting homeostatic expansion of autoreactive CD4+ T cells in the K/BxN mouse model.

OBJECTIVE: K/BxN-transgenic mice are a model of autoimmune arthritis, similar to rheumatoid arthritis. This study was undertaken to determine whether inhibition of lymphopenia-provoked homeostatic expansion can prevent spontaneous development of disease in the K/BxN model. METHODS: To inhibit homeostatic expansion of autoreactive T cells, K/BxN mice with disease in the preclinical stage were adoptively transferred with CD4+ T cells purified from nontransgenic BxN or Thy1.1+ BxN mice. To observe the profile of proliferation of CD4+ T cells derived from the hosts, carboxyfluorescein diacetate succinimidyl ester-labeled autologous CD4+ T cells were cotransferred to K/BxN mice together with BxN CD4+ T cells. Disease onset and progression were scored, and the dynamics and phenotypes of recipient CD4+ T cells were determined by flow cytometry, before and after cell infusion. RESULTS: During the preclinical phase of disease, K/BxN mice exhibited CD4+ T lymphopenia, which was followed by a compensatory expansion of these cells during the early clinical phase. The majority of CD4+ T cells acquired a memory phenotype (CD44(high),CD62L(low),CD25-), which is a hallmark of homeostatically expanding cells. Importantly, K/BxN mice subjected to syngeneic T cell transfer did not develop symptoms of arthritis and also possessed fewer transgenic T cell receptor-encoded Vbeta6+,CD4+ T cells. This effect was associated with decreased proliferation of recipient-derived CD4+ T cells but not with the function of CD25+ T regulatory cells present in donor cells. CONCLUSION: These results provide the first evidence that lymphopenia-associated homeostatic proliferation of autoreactive CD4+ T cells potentiates autoimmune arthritis, and that inhibition of this process protects mice from the development of this pathologic condition.

Pleural cryptococcosis with idiopathic CD4 positive T-lymphocytopenia.

A 19-year-old man was admitted to our hospital because of chest pain. He was diagnosed as having pleural cryptococcosis by pleural biopsy. His CD4 positive T-lymphocyte count was low (< 300 microl) and there was no evidence of human immunodeficiency virus infection. He was successfully treated with fluconazole. However, his CD4 positive lymphocyte counts remained low after the recovery and he was diagnosed as idiopathic CD4 positive T-lymphocytopenia. Pleural cryptococcosis is rare and its predisposing condition is still controversial. To our knowledge, this is the first case of pleural cryptococcosis associated with idiopathic CD4 positive T lymphocytopenia.

CD4+ T-lymphocytopenia--a frequent finding in anti-SSA antibody seropositive patients with primary Sjögren's syndrome.

OBJECTIVE: Case reports have described an association between idiopathic CD4+ T-lymphocytopenia (ICL) and non-Hodgkin's malignant lymphoma (NHML), and both entities have an increased prevalence in patients with primary Sjögren's syndrome (SS). We investigated lymphocyte subset counts in patients with primary SS to determine if presence of different autoantibodies is associated with ICL and hence may represent an increased risk for development of NHML. METHODS: A total of 80 patients with primary SS according to the American-European Consensus Classification Criteria (AECC) and 37 non-AECC sicca patients were studied for presence of different autoantibodies, and lymphocyte subsets were investigated by flow cytometry. RESULTS: Absolute CD4+ T-lymphocyte counts were significantly lower among anti-SSA antibody seropositive SS patients compared to correlating seronegatives and non-AECC sicca patients (601/microl vs 956/microl and 1087/microl; p < 0.001 and p < 0.001, respectively). ICL was found in 16% of anti-SSA seropositive patients. CONCLUSION: ICL, a proposed risk factor for development of NHML, occurs frequently and presumably exclusively in patients with primary SS who are anti-SSA antibody seropositive. These findings support that this group comprises patients at risk for development of NHML.

Cutaneous infections by papillomavirus, herpes zoster and Candida albicans as the only manifestation of idiopathic CD4+ T lymphocytopenia.

BACKGROUND: Selective depletion of CD4+ T lymphocytes is common in both primary and secondary immunodeficiencies. Idiopathic CD4+ T lymphocytopenia (ICL) cases are defined as a persistent CD4+ T lymphocyte count of less than 300x10(6) cells/L and/or less than 20% of the total T-cell count. METHOD: A 40-year-old woman, with a history of psoriasis and paracetamol allergy, presented with persistent warts of the hands and condylomas of the ano-genitalia. Histological and virological analysis was carried out on genital and cutaneous lesions and peripheral blood. RESULTS: Serology for HIV-1, HIV-2, Epstein-Barr virus and parvovirus B19 were negative. There was lymphopenia of 10% CD4+ cells, with normal numbers of total leukocytes; there were no other-abnormal immunological findings. DNA analysis of cutaneous lesions revealed HPV-49 and HPV-3 in the hands and HPV-6 in the genital region. CONCLUSIONS: The cause of the ICL in this patient is unknown. HPV is not known to be an immunosuppressive agent; it remains to be determined whether the HPV-associated lesions are the cause or the result of immunosuppression.