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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

X-linked agammaglobulinemia (XLA) is usually considered a disorder of B cell development; however, the gene that is defective in XLA encodes a cytoplasmic tyrosine kinase called Btk, that is expressed throughout myeloid as well as B cell differentiation. A review of medical records of patients in whom mutations in Btk had been identified indicated that 13 of 50 patients (26%) had experienced episodes of profound neutropenia. In 12 of the 13 patients, neutropenia was part of the acute illness that precipitated an evaluation for immunodeficiency. These boys were more likely to be less than a year of age at the time of diagnosis and they were less likely to have a family history of immunodeficiency. Neutropenia was associated with staphylococcal or pseudomonas sepsis in 6 of the patients. The duration of neutropenia was variable but was often more than 1 week. Neutropenia was not seen in any patient with XLA receiving intravenous gammaglobulin. Although neutropenia was not associated with any specific mutation in Btk, most of the alterations in this gene in the patients with XLA and neutropenia resulted in the absence of Btk protein or in amino acid substitutions in sites thought to be critical to Btk function. Btk may not be required for neutrophil production under normal circumstances; however, it may play a role in the response to stress.
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PMID:Neutropenia in X-linked agammaglobulinemia. 893 4

Common variable immunodeficiency (CVI) is a primary immunodeficiency characterized by deficient antibody production. The cause of this immunodeficiency is unknown; several in vitro studies have revealed a significant number of alterations that could explain the hypogammaglobulinemia present in this syndrome. Among those described are primary B cell alterations, numerical and functional T cell abnormalities, and defects in the interaction between accessory cells. The alteration typical of CVI is the failure of B lymphocytes to differentiate from antibody-producing cells, resulting in deficient immunoglobulin secretion. Among the T cell abnormalities described are a diminished proliferative response to mitogens and antigens, alterations in the level of production of several cytokines, especially reduction in the production of IL-2, diminished antigen-specific T cells and increase basal apoptosis after stimulation. Antigen presenting cells, monocytes and dendritic cells can also present alterations and contribute to deficient antigen response. The clinical manifestations of these patients is variable; most present recurrent bacterial infections due to encapsulated bacteria, especially sinusitis, otitis, bronchitis, and pneumonias. A few patients can present mycobacterial or fungal infection and occasionally Pneumocystis carinii. Viral infection is uncommon in these patients although some suffer recurrent herpes zoster infection. Clinical features of septicemia and central nervous system infections are less frequent. The incidence of digestive tract infections in these patients is high. The most common cause of diarrhea is Giardia lamblia; Salmonella, Shigella and Campylobacter are also common pathogens. Autoimmune disease is also more prevalent in these patients than in the general population. The most frequently associated diseases are hemolytic anemia, idiopathic thrombocytopenic purpura and autoimmune neutropenia. Cancer is also frequently associated with CVI, the most common forms being lymphoproliferative syndromes, especially non-Hodgkin's lymphoma. Granulomas are a unusual manifestation in some patients with CVI; their localization varies but the most commonly affected organs are the spleen and lungs. Some authors have compared these granulomas with those characterizing sarcoidosis, especially when appearing in the lung. Diagnosis of CVI is usually by exclusion of other diseases, such as cystic fibrosis, immotile cilia syndrome or allergic processes. CVI should be suspected in all patients with recurrent bacterial infections especially those localized in the respiratory tract. Other primary immunodeficiencies which present clinical findings similar to CVI and which should be ruled out are selective IgG subclass deficiency, IgA deficiency and selective deficiency in the response to polysaccharide antigens with normal immunoglobulin levels. The serum hypogammaglobulinemia present in all patients with CVI provides the diagnostic key. The age at which clinical manifestations appear, the absence of familial antecedents and the presence of circulating B lymphocytes form the basis of the differential diagnosis between X-linked agammaglobulinemia and autosomal recessive forms. The treatment of choice of patients with CVI is treatment with human gamma-globulin. Currently, the most common route of administration is intravenous; these molecules have a half-life of approximately 21 days and a high degree of safety concerning the possible transmission of viral infections. Adverse reactions are generally few and clinically unimportant. The most frequently used doses oscillate between 200 and 400 mg/kg body weight every 2-4 weeks. Both the dose and its frequency should be personalized for each patient. Early diagnosis of patients with CVI, application of treatment with appropriate antibiotics for infections and treatment with gamma-globulins prevent long-term complications of this disease and dramatically improve the quality of life and life expectancy of these patients.
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PMID:[Common variable immunodeficiency. Review]. 1143 84

The primary immunodeficiency diseases are a heterogeneous group of more than 75 disorders characterized by intrinsic defects in the functions of the immune system. Many are associated with abnormalities of hematopoiesis as well. This article will review those primary immunodeficiency syndromes in which neutropenia is a prominent finding, including X-linked agammaglobulinemia (XLA), hyper IgM syndrome, common variable immunodeficiency (CVID), IgA deficiency, cartilage-hair hypoplasia (CHH), and reticular dysgenesis, with regards to pathophysiologic findings and treatment.
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PMID:Neutropenia associated with primary immunodeficiency syndromes. 1195 93

In this case study authors presented the clinical characteristics of X-linked agammaglobulinemia (XLA) associated with agranulocytosis diagnosed in a 2-year-old boy. Affected child lacked circulating mature B cells, presented low levels of serum immunoglobulins, but did not suffer from recurrent bacterial infections. XLA is a primary immunodeficiency caused by a defective tyrosine kinase (Btk) in B cells. Our patient and his mother have a mutation in the BTK gene, described as W281X. During therapy with intravenous gammaglobulin, the boy has not experienced agranulocytosis. It is important to consider a primary immunodeficiency diagnosis when a child presents agranulocytosis or neutropenia and a recurrent infectious disease.
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PMID:[X-linked agammaglobulinemia (XLA) associated with agranulocytosis--case report]. 1496 69

X-linked agammaglobulinemia (XLA) is clinically characterized by recurrent bacterial infections during early infancy. Although it is not a phagocytic disorder, XLA is sometimes associated with neutropenia. We conducted a nation-wide survey to determine the frequency of neutropenia among Japanese XLA patients. Responses were received from 87 (86%) of 101 patients in which BTK mutations were previously identified, and of these, 16 (18%) had neutropenia. All episodes of neutropenia occurred before initiation of intravenous immunoglobulin (IVIG) replacement therapy. Two XLA patients died of multiple organ failure caused by severe neutropenia and Pseudomonas sepsis before initiation of IVIG replacement therapy. These results suggest that, in some cases, severe bacterial infections in XLA patients might be caused not only by antibody deficiencies but also by neutropenia.
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PMID:Severe neutropenia in Japanese patients with x-linked agammaglobulinemia. 1616 Sep 18

X-linked agammaglobulinemia (XLA) is a primary immunodeficiency caused by mutations in the gene for Bruton tyrosine kinase (BTK) that result in the deficient development of B lymphocytes and hypogammaglobulinemia. Because the disorder is uncommon, no single institution has had sufficient numbers of patients to develop a comprehensive clinical picture of the disorder. Accordingly, a national registry of United States residents with XLA was established in 1999 to provide an updated clinical view of the disorder in a large cohort of patients. A total of 201 patients were registered by 66 physicians. The estimated birth rate for the 10-year period of 1988-1997 was 1/379,000. Infection was the most common initial clinical presentation (85%), followed by a positive family history (41%) and neutropenia (11%). Although the average age of diagnosis was younger in patients with a positive family history (mean, 2.59 yr) than in patients with a negative family history (mean, 5.37 yr) (p < 0.001), only 34.5% of patients with a positive family history at the time of their birth were diagnosed before clinical symptoms developed-that is, based on family history alone. Seventy percent of patients had at least 1 episode of otitis, 62% at least 1 episode of pneumonia, 60% at least 1 episode of sinusitis, 23% at least 1 episode of chronic/recurrent diarrhea, 21% at least 1 episode of conjunctivitis, 18% at least 1 episode of pyoderma and/or cellulitis, 11% at least 1 episode of meningitis/encephalitis, 10% at least 1 episode of sepsis, 8% at least 1 episode of septic arthritis, 6% at least 1 episode of hepatitis, and 3% at least 1 episode of osteomyelitis. Fourteen of 201 (6.9%) patients were dead at the time they were entered in the Registry. However, in a prospective 4 /4-year follow-up of living patients, only 3/80 (3.75%) patients died. Causes of death included disseminated enterovirus infection (n = 6), pulmonary insufficiency (n = 5), adenovirus infection (n = 1), sepsis (n = 1), acquired immunodeficiency disease syndrome (AIDS) (n = 1), myocarditis (n = 1), hepatitis (n = 2), and stem cell transplantation (n = 1).
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PMID:X-linked agammaglobulinemia: report on a United States registry of 201 patients. 1686 44

Neutropenia is characterized by decrease in the absolute number of circulating neutrophils and an increase susceptibility to infections. The current study was performed in order to explain the clinical and laboratory findings of patients with antibody deficiency disorders associated neutropenia. The patients' records of 19 neutropenic cases out of 207 patients with antibody deficiencies, who had been referred to Children's Medical Center and enrolled in Iranian primary immunodeficiency registry, were reviewed. Nineteen cases (14 male and 5 female), with a mean age of 10.7+/-5.7 years, were associated with neutropenia (9.2%). The disorders with associated neutropenia were Hyper IgM syndromes (3 of 8), Common variable immunodeficiency (13 of 109), and X-linked agammaglobulinemia (3 of 45). The median age for the onset of disease and diagnosis age were 15 months (1-134) and 3.8 years (6 months-13 years), respectively. The most common infections during the course of illness were pneumonia (13 cases), diarrhea (12 cases), oral candidiasis (9 cases), otitis media (6 cases), sinusitis (6 cases), cutaneous infections (5 cases), and abscess (5 cases). Other less frequent infections were: conjunctivitis, oral ulcers, meningitis, and osteomyelitis. Three neutropenic patients died because of recurrent infections. Neutropenia may occur in any of the primary immunodeficiency disorders. Persistent or severe infections always pose a supposition, which deserves further evaluation for detecting an underlying immune deficiency syndrome and neutropenia, since a delay in diagnosis may result in a serious organ damage or even death of the patient.
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PMID:Neutropenia in patients with primary antibody deficiency disorders. 1730 96

X-linked agammaglobulinemia (XLA) is a primary B-cell deficiency syndrome with an incidence of 5 to 10 cases per million. The current treatment approach includes intravenous immunoglobulin and aggressive antibiotic regimens for infections. Besides recurrent infections, XLA patients may present with other manifestations, such as alopecia, enteropathy, amyloidosis, and neutropenia. Neutropenia, which has been shown in up to 25% of affected patients, might also contribute to the degree of severity of bacterial infections that have been reported in these cases. Here we present our experience with the granulocyte colony-stimulant factor, filgrastim (Neupogen), in the treatment of neutropenia in a 14-month-old child with XLA.
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PMID:XLA-associated neutropenia treatment: a case report and review of the literature. 1879 45

Patients with congenital immunodeficiency (CID) syndromes are susceptible to various microorganisms. However, relatively few CID disorders develop mycobacterial disease. We describe clinical features, laboratory findings and therapeutic outcome of children with CID who had tuberculosis disease. Medical reports of 10 patients were reviewed. Three patients had chronic granulomatous disease, two had common variable immuno deficiency, the others had cyclic neutropenia, combined immunodeficiency, hyperimmunoglobulin E syndrome, selective IgA deficiency and X-linked agammaglobulinemia. Eight patients presented with pulmonary tuberculosis, one had tuberculosis arthritis, one had tuberculosis osteomyelitis. There was acid fast bacilli in sputum of two, bone marrow aspiration in one and postmortem lung biopsy specimen in one patient. Mycobacterium tuberculosis grew in sputum of one and articular fluid aspirate of one patient. One patient was diagnosed with bone biopsy specimens characteristic for tuberculosis. The remaining three patients were diagnosed to have tuberculosis disease as they had positive tuberculin skin test and clinical and radiologic findings unresponsive to non-specific treatment. All patients were treated with antituberculous drugs. Mycobacterium species may be important pathogens in children with CID, especially in endemic regions.
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PMID:Tuberculosis in children with congenital immunodeficiency syndromes. 2051 30

X-linked agammaglobulinemia (XLA) or Bruton disease is a relatively rare constitutionally immune disorder due to a genetic mutation of BTK (Bruton tyrosine kinase) gene which encodes for BTK protein. BTK is a signal-transducing protein expressed in hematopoietic lineages. The genetic disorder is responsible for B cell lymphocytes' maturation arrest. The humoral immunodeficiency caused by BTK mutation is linked with recurrent bacterial and viral infections. Genetic investigations of the prepositus as well as the other members of the family are necessary to characterize a mutation in BTK gene to confirm the diagnosis and reveal a hereditary transmission or de novo mutation. Authors propose and comment a case report of an 8 month old child who suffers from Bruton disease. Initial presentation was neutropenia, but genetic investigation has revealed a previously non-reported mutation in the BTK gene. The same mutation was found in the mother with low expression of BTK in monocytes and normal in B-cells suggesting a lineage specific extinction of BTK which has never been reported before.
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PMID:A new mutation that predicted a drastic alteration of the BTK protein function. 2377 91


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