11/357. Impairment of STAT activation by IL-12 in a patient with atypical mycobacterial and staphylococcal infections.IL-12 plays a pivotal role in the stimulation of immune responses against intracellular infections. This role is manifested in the increased susceptibility to atypical mycobacterial and salmonella infections among individuals whose lymphocytes lack expression of IL-12Rbeta1. Here, we report on a patient with mycobacterium avium infection, recurrent staphylococcus aureus sinusitis, and multiple adverse drug reactions whose T cells were unable to produce IFN-gamma or proliferate in response to IL-12 despite the expression of wild-type IL-12Rbeta1 and IL-12Rbeta2. The defect in these functional responses to IL-12 was selective, as cytolytic activity induced by IL-12 was intact, and lymphocytes were responsive to stimulation by IL-2. An examination of cytokine signaling revealed that STAT4 and extracellular regulated kinase 1 (ERK1) activation by IL-12 was intact, whereas the activation of STAT1, -3, and -5 by IL-12 was lost. This impairment of STAT activation was specific for IL-12, as STAT activation by IL-2, IL-15, and IFN-gamma was unaffected. These findings demonstrate that the activation of STAT4 alone is not sufficient for IL-12-induced IFN-gamma production and proliferation and suggest that other STATs play a role in these responses to IL-12. While the etiology of the impaired IL-12 signaling in this patient has not yet been elucidated, the absence of mutations in IL-12Rbeta1 or IL-12Rbeta2 and the preservation of STAT4 activation raise the possibility that there may be a mutation in an as yet undiscovered component of the IL-12 signaling complex that is normally required for the recruitment and activation of STAT1, -3, and -5.- - - - - - - - - - ranking = 1keywords = infection (Clic here for more details about this article) |
12/357. A novel X-linked disorder of immune deficiency and hypohidrotic ectodermal dysplasia is allelic to incontinentia pigmenti and due to mutations in IKK-gamma (NEMO).Hypohidrotic ectodermal dysplasia (HED), a congenital disorder of teeth, hair, and eccrine sweat glands, is usually inherited as an X-linked recessive trait, although rarer autosomal dominant and recessive forms exist. We have studied males from four families with HED and immunodeficiency (HED-ID), in which the disorder segregates as an X-linked recessive trait. Affected males manifest dysgammaglobulinemia and, despite therapy, have significant morbidity and mortality from recurrent infections. Recently, mutations in IKK-gamma (NEMO) have been shown to cause familial incontinentia pigmenti (IP). Unlike HED-ID, IP affects females and, with few exceptions, causes male prenatal lethality. IKK-gamma is required for the activation of the transcription factor known as "nuclear factor kappa B" and plays an important role in T and B cell function. We hypothesize that "milder" mutations at this locus may cause HED-ID. In all four families, sequence analysis reveals exon 10 mutations affecting the carboxy-terminal end of the IKK-gamma protein, a domain believed to connect the IKK signalsome complex to upstream activators. The findings define a new X-linked recessive immunodeficiency syndrome, distinct from other types of HED and immunodeficiency syndromes. The data provide further evidence that the development of ectodermal appendages is mediated through a tumor necrosis factor/tumor necrosis factor receptor-like signaling pathway, with the IKK signalsome complex playing a significant role.- - - - - - - - - - ranking = 0.14285714285714keywords = infection (Clic here for more details about this article) |
13/357. Long-term study of a female hyper-IgM immunodeficiency.Hyper-IgM immunodeficiency (HIM) is an immunological disorder characterized by normal or elevated serum IgM levels, and reduced serum IgG and IgA levels, due to the disruption of immunoglobulin class switching in B cells. X-linked hyper-IgM is caused by the defective expression of the cd40 ligand on activated T cells, which induces immunoglobulin class switching along with some cytokines, such as interleukin 4, by the signal transduction of CD40 in B cells. We report on a Japanese girl who initially showed low serum IgM, IgG and IgA levels like patients with common variable immunodeficiency; however, in the course of time, serum IgG levels became reduced and serum IgM levels increased, resulting in the typical immunoglobulin profile of HIM. neutropenia, one of the features of X-linked HIM, was not observed. In spite of extremely low serum IgG levels, she did not show any predisposition to severe infection, even without gammaglobulin replacement therapy. No mutation of the cd40 ligand or CD40 was detected. Sequencing of the complementarity-determining region of immunoglobulin heavy-chain genes in peripheral B lymphocytes revealed that they were all in frame, and insertion of the N region was detected. These results indicate that the heavy-chain gene rearrangement in the patient's B cells is intact. Non-X-linked HIM has heterogeneous pathogenetic mechanisms, and some groups may show the resistance to infection at the healthy donor level. The underlying defects in non-X-linked HIM might be specifically involved in class switching.- - - - - - - - - - ranking = 0.28571428571429keywords = infection (Clic here for more details about this article) |
14/357. Selective T-cell deficiency in Turner's syndrome.The case of a 29-year-old Caucasian woman with 45 X0 karyotype, known as Turner's syndrome, and a recently diagnosed selective T-cell deficiency is reported. The main clinical features of the patient were recurrent sinopulmonary infections and a negative skin test with seven common recall antigens. Laboratory findings included lymphocytopenia, highly elevated CD45RA/CD45R0 ratio, as well as reduced expression of the co-stimulatory molecules CD154, CD86, CD80 and CD28 on CD4 cells in combination with disturbed lymphocyte transformation in vitro. Markedly decreased levels of interleukin (IL)-2R, both on lymphocyte surface as well as the soluble analog, suggest a new form of x-linked immunodeficiency associated with Turner's syndrome.- - - - - - - - - - ranking = 0.14285714285714keywords = infection (Clic here for more details about this article) |
15/357. Humoral immunodeficiency with facial dysmorphology and limb anomalies: a new syndrome.We report a 6 year old girl with an isolated humoral immune deficiency and a unique combination of dysmorphic features. Physical findings include microcephaly, micrognathia, sickle shaped eyebrows, hypoplastic alae nasi, thenar hypoplasia, partial 4-5 syndactyly of toes, recessed great toes, anterior anus, and hypoplastic labia minora. Radiographic findings include triphalangeal thumbs and hypoplastic first metatarsals. She has postnatal growth retardation and her development is substantially slower than her twin's. Her clinical course has been complicated by recurrent sinopulmonary infections and pneumococcal bacteraemia. Laboratory evaluation revealed hypogammaglobulinaemia, absent B cells, and a 46,XX karyotype. A review of the literature and the london Dysmorphology database did not produce any recognizable syndromes that match her constellation of findings. She may represent a unique syndrome of unknown etiology.- - - - - - - - - - ranking = 0.14285714285714keywords = infection (Clic here for more details about this article) |
16/357. Microcystic adnexal carcinoma associated with primary immunodeficiency, recurrent diffuse herpes simplex virus infection, and cutaneous T-cell lymphoma.Cutaneous microcystic adnexal carcinoma (MAC) is a rare and poorly understood tumor that predominantly occurs in the head and neck. MAC usually affects people in their fourth and fifth decades. Some patients have had a history of radiation. We present a case of MAC occurring in the left antecubital fossa of an 18-year-old white woman with an unusual immunodeficiency syndrome. The patient also developed a squamous cell carcinoma, a cutaneous T-cell malignancy, and a perigastric leiomyoma. A congenital infection of herpes simplex virus (HSV) persisted throughout her life. The association of HSV infection with MAC and squamous cell carcinoma and that of peripheral T-cell lymphoma with Epstein-Barr virus is discussed in relation to her immunodeficiency.- - - - - - - - - - ranking = 0.85714285714286keywords = infection (Clic here for more details about this article) |
17/357. Clinical and immunological spectrum of partial digeorge syndrome.We present four cases of digeorge syndrome diagnosed at our center. Onset occurred during the neonatal period and was associated with severe congenital heart disease. In case 1, the patient had heart disease and absence of thymus. Total t-lymphocytes were 34%; total T4-lymphocytes were 27%. Stimulation test with phytohemagglutinin (PHA), concanavalin a (conA) and pokeweed mitogen were negative. Microdeletion was found in the chromosome 22q11 region. The second case involved heart disease, microstomia, round and rotated ears and branchial cyst. Total t-lymphocytes were 38% and total T4-lymphocytes 27%. Thymus was absent. Microdeletion in the chromosome 22q11 region. Case 3 showed heart disease, renal malformation, absence of thymus and parathyroid gland. The patient died 5 days postsurgery. Microdeletion was seen at chromosome 22q11. In the fourth case there was heart disease, microretrognathia, hypertelorism, short neck, absence of thymus and parathyroid glands. Total t-lymphocytes were 22%, total T4-lymphocytes 15%, and total T lymphocytes for pokeweed mitogen were negative. Microdeletion was found at chromosome 22q11. At the age of 13 days the patient died. The cases were recorded during a 2-year period, between 1997 and 1998. The prevalence of digeorge syndrome in the number of admissions for congenital heart disease among the neonates at our hospital was 3.14%. Presentation in the form of repeated infections is rare, since most cases of digeorge syndrome are partial, and functional cellular immunity is preserved.- - - - - - - - - - ranking = 0.14285714285714keywords = infection (Clic here for more details about this article) |
18/357. cryptosporidiosis in an immunosuppressed renal-transplant recipient with iga deficiency.Cryptosporidia are sporozoan parasites that infect epithelial cells of the gastrointestinal tract. Infection with cryptosporidia has been found most commonly in a variety of animal species and only rarely in man. The authors report a case of an immunosuppressed renal-transplant recipient with iga deficiency who experienced diarrhea and fever and was found to have cryptosporidia in a jejunal biopsy specimen and in air-dried smears of the specimen. By electron microscopy, trophozoite, schizont, and macrogamete forms were identified, and these forms ahd morphologic features similar to those of cryptosporidia previously found in guinea pigs. Treatment of the cryptosporidial infection in this case was with trisulfapyrimidines. The efficacy of this treatment could not be evaluated because of complications.- - - - - - - - - - ranking = 0.14285714285714keywords = infection (Clic here for more details about this article) |
19/357. Treatment of EBV driven lymphoproliferation with erythrophagocytosis: 12 year follow up.This is a report of a case of Epstein-Barr virus (EBV) associated haemophagocytic syndrome in a 17 year old woman with antibody deficiency. For two years before this presentation, serology showed abnormally high titres to EBV early antigen, suggestive of persistent infection with EBV. She became acutely unwell with clinical features consistent with virus associated haemophagocytic syndrome (VAHS). histology showed lymphoproliferation with erythrophagocytosis and evidence of EBV encoded RNAs in liver, spleen, and lymph node. VAHS is often fatal, particularly when it occurs in patients with underlying immunodeficiencies. In this case, treatment with intravenous immunoglobulin, aciclovir, and alpha interferon was followed by a dramatic recovery. Twelve years later the patient remains relatively well on regular intravenous immunoglobulin.- - - - - - - - - - ranking = 0.14285714285714keywords = infection (Clic here for more details about this article) |
20/357. Familial CD8 deficiency due to a mutation in the CD8 alpha gene.CD8 glycoproteins play an important role in both the maturation and function of MHC class I-restricted T lymphocytes. A 25-year-old man, from a consanguineous family, with recurrent bacterial infections and total absence of CD8( ) cells, was studied. Ab deficiencies and ZAP-70 and TAP defects were ruled out. A missense mutation (gly90-->ser) in both alleles of the immunoglobulin domain of the CD8 alpha gene was shown to correlate with the absence of CD8 expression found in the patient and two sisters. Conversely, high percentages of CD4(-)CD8(-)TCR alpha beta( ) T cells were found in the three siblings. A novel autosomal recessive immunologic defect characterized by absence of CD8( ) cells is described. These findings may help to further understanding of the role of CD8 molecules in human immune response.- - - - - - - - - - ranking = 1.3379966990983keywords = bacterial infection, infection (Clic here for more details about this article) |
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