ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Clearance of mucus and other debris from the airways is achieved by 3 main mechanisms: mucociliary activity, coughing, and alveolar clearance. Disorders of ciliary structure or function results in impaired clearance, and result in chronic sinopulmonary disease manifested as chronic sinusitis, otitis media, nasal polyposis, and ultimately bronchiectasis. In addition, situs inversus, dextrocardia, and infertility can be associated with dysfunctional ciliary activity. The termprimary ciliary dyskinesiahas been proposed for the spectrum of these diseases. The termKartagener syndromeapplies to this syndrome when accompanied by infertility and dextrocardia or situs inversus. The more common types of ciliary dysmotility syndromes are characterized by missing dynein arms, central microtubule pairs, inner sheath, radial spokes, or nexin links. In addition to structural defects within the cilia, disordered ciliary beating and disordered ciliary arrays on epithelial cell surfaces have been described in this syndrome. Treatment includes rigorous lung physiotherapy, prophylactic and organism-specific antibiotics, and immunization against common pulmonary pathogens. Late stages of the disease may require surgical intervention for bronchiectasis or lung transplant for end-stage lung disease.

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The triad of reversible airway obstruction, bronchial hyperresponsiveness, and airway inflammation characterizes asthma. The etiology of asthma is complex and involves the interaction of multiple genetic foci and a variety of environmental factors, such as protein allergens, chemical sensitizers, and viral or bacterial proteins. Candidate asthma genes have been identified that may be linked or associated with the asthmatic phenotype. Potential candidate asthma genes include cytokine genes, receptor genes, transcription factors, immune recognition genes, and genes regulating lipid mediator generation. Although polymorphisms within either the promoter or coding region of individual asthma candidate genes have been identified, the association between these genetic polymorphisms and the asthmatic phenotype remains incompletely defined. Furthermore, genetic polymorphisms mediating the asthmatic phenotype are rarely identified in individual patients. This manuscript reviews several of the specific mutations and polymorphisms that have been identified in candidate asthma genes, such as the high affinity IgE receptor, the &bgr;2-adrenergic receptor, the interleukin-4 promoter and receptor, the tumor necrosis factor gene, and the 5-lipoxygenase promoter.

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Lymphangioleiomyomatosis (LAM), a rare disorder of unknown cause that occurs almost exclusively in women of childbearing years, is characterized microscopically by abnormal smooth muscle proliferation in the lung, lymphatics, and mediastinal, abdominal and lower cervical lymph nodes. LAM is associated with progressive dyspnea, recurrent pneumothoraces, chylous effusions, abdominal tumors (angiomyolipoma), and chylous ascites. Because of the predilection of this disease for young women, therapies to date have mainly involved hormonal manipulation. Although the efficacy of these therapies has not been established, the clinical course is more favorable in recent studies compared with earlier reports.

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Surfactant protein B (SP-B) deficiency is a disorder of surfactant function with complete or transient absence of SP-B in term neonates. SP-B, 1 of 4 described surfactant-associated proteins, plays a key role in surfactant metabolism, particularly in intracellular packaging of surfactant components, formation of tubular myelin, and the presentation of the surfactant phospholipid monolayer to the air-fluid interface within the alveolus. Neonates with clinical SP-B deficiency best demonstrate the key role of SP-B in surfactant function. “Classic” deficiency results in severe respiratory failure in term infants and death unless lung transplantation is performed. Because the initial description of complete deficiency secondary to a homozygous frameshift mutation in codon 121 of the SP-B cDNA, partial deficiencies with differing genetic backgrounds and less severe clinical courses have been reported. These partial deficiency states may provide a clearer picture of genotype/phenotype relationships in SP-B function and surfactant metabolism. SP-B deficiency or dysfunction may be more common than once thought and may play a significant role in neonatal lung disease

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

&agr;1-antitrypsin (&agr;1AT) deficiency is a common lethal hereditary disorder of white persons of European descent. The condition is characterized by reduced serum levels of &agr;1AT, a 52-kDa glycoprotein synthesized chiefly in the liver and, to a lesser extent, by macrophages and neutrophils. &agr;1AT acts as an antiprotease and is the physiological inhibitor of neutrophil serine proteases such as neutrophil elastase cathepsin G and proteinase 3. The clinical manifestations of &agr;1AT deficiency occur chiefly in the lung, with a high risk of emphysema occurring by the third or fourth decade of life. Cigarette smoking accelerates the development of emphysema in persons with &agr;1AT deficiency. There is also an increased risk of liver disease in &agr;1AT deficiency, which occurs mostly in childhood. In this review, we will define further the diagnosis of &agr;1AT deficiency and its clinical manifestations and describe the therapeutic strategies that are currently being developed to treat the hepatic and pulmonary disease associated with this condition.

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Common variable immunodeficiency (CVI) is a heterogeneous immunodeficiency syndrome characterized by hypogammaglobulinemia, recurrent bacterial infections, and a variety of immunological abnormalities. In addition to recurrent infections, patients with this syndrome also suffer from an increased incidence of autoimmune disease and malignancy. Because the spectrum of associated diseases is broad, patients with CVI are seen by a variety of medical specialists. In this review, the pathogenesis, clinical manifestations, diagnosis, and treatment of CVI are discussed.

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The nontuberculous mycobacteria are for the most part ubiquitous environmental organisms that only rarely cause disease in humans. Therefore, the normal host defense against these organisms must be quite robust, as exposure is universal and disease is rare. The organisms that are most commonly encountered in clinical practice,Mycobacterium avium,M intracellulare,M kansasii,M fortuitum,M abscessus, andM chelonae, are frequently found in water sources and soil.1These organisms share significant structural and biochemical similarities with their more pathogenic relative,M tuberculosis(MTB). Because they are of significantly lower pathogenicity than MTB, patients with abnormal susceptibility to these infections should include those with defects that may be identifiable. Study of these patients should lead to determination of the mechanisms underlying resistance to these organisms, which in turn are likely to be highly informative regarding host defense against these infections and their more virulent relative MTB. Furthermore, recognition of host factors that permit infection with nontuberculous mycobacteria in otherwise normal hosts will identify pathways that can be targeted for therapeutic intervention. Thus, the search for genetic and acquired susceptibility to nontuberculous mycobacteria is also a search for susceptibility factors for MTB as well as an opportunity to recognize endogenous pathways that can be exploited therapeutically.

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Pneumocystis cariniiis an important, but sporadic, opportunistic pulmonary pathogen in immunosuppressed HIV seronegative persons. Historically, patients at highest risk forP cariniipneumonia are included infants with severe malnutrition, children with primary immunodeficiencies, patients with hematological malignancies, and recipients of solid organ or bone marrow transplants. Recently, solid tumor patients, in particular those receiving high-dose corticosteroids for brain neoplasms, and patients with inflammatory or collagen-vascular disorders, especially patients with Wegener granulomatosis receiving immunosuppressive therapy, have been identified as subgroups at increased risk forP cariniipneumonia. Other factors associated withP cariniipneumonia include the intensity of the immunosuppressive regimen and tapering doses of corticosteroids. BecauseP cariniipneumonia is associated with significant morbidity and mortality, it is important to identify high-risk patient populations to administer effective chemoprophylactic agents, such as trimethoprim- sulfamethoxazole.

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Erdheim-Chester disease (ECD) is a rare multisystem histiocytosis syndrome of unknown cause that usually affects adults. Histiocytic infiltration of multiple end organs produces bone pain, xanthelasma and xanthoma, exophthalmos, diabetes insipidus, and interstitial lung disease. Differential diagnosis includes Langerhans cell histiocytosis, metabolic disorders, malignancy, and sarcoidosis. ECD can be diagnosed using a combination of clinical and histopathologic findings. Sites of involvement include lung, bone, skin, retro-orbital tissue, central nervous system, pituitary gland, retroperitoneum, and pericardium. Symmetrical long bone pain with associated osteosclerotic lesions, xanthomas around the eyelids, exophthalmos, and/or diabetes insipidus suggest ECD. Approximately 35% of patients have associated lung involvement, characterized by interstitial accumulations of histiocytic cells and fibrosis in a predominantly perilymphangitic and subpleural pattern. This pattern distinguishes ECD from other histiocytic disorders involving the lung. The diagnosis is confirmed by tissue biopsies that contain histiocytes with non-Langerhans cell features. In general, the clinical course of patients with this disease varies, and the prognosis can be poor despite treatment. Clinical trials for treatment of ECD have not been conducted and treatment is based on anecdotal experience.

ISSN:0002-9629    

出版商:OVID    

年代:2001

数据来源: OVID