摘要:

The endemic fungiHistoplasma capsulatum, Coccidioides immitis,andBlastomyces dermatitidistend to reside in specific geographic regions. The organisms are pathogenic in that they are able to produce clinical disease in both immunocompromised patients and in patients with normal immunity. These organisms have a variety of clinical presentations, some of which typically are seen in the normal host and others that are primarily encountered in persons with abnormal immunity. Although most of the cases are seen in endemic regions, they may occur in persons who at some time either resided in or traveled to an endemic region.

ISSN:0883-5993    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Immunocompromised hosts have defects in their immune system that make them at risk of developing a variety of infections. In addition, these persons may develop a wide variety of noninfectious disease processes that involve the lung. These disorders may be caused by the underlying disease process. This may be seen with the development of metastatic disease from the underlying neoplasm, or it may represent the development of a malignancy secondary to therapy, as is seen with posttransplant lymphoproliferative disease. The abnormalities may be a result of the therapy used to treat the patients, as is seen with radiation injury to the lung and drug toxicity. Pulmonary edema may occur and be from a wide variety of causes. All of these disease processes may simulate an infectious process and must be differentiated from infection to allow proper therapeutic intervention.

ISSN:0883-5993    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Viruses andPneumocystis cariniiare significant causes of pneumonia in immunocompromised patients, particularly patients with impaired cell-mediated immunity. They are often simultaneously considered in the differential diagnosis of diffuse pneumonitis in these patients and, because radiographic appearances and the periods of vulnerability to these infections may overlap, may be difficult to differentiate. This article will correlate radiographic findings to evolving histopathologic changes in select specific infections, as they affect three different immune impaired populations: (a) acquired immunodeficiency syndrome, (b) immunosuppression secondary to therapy for underlying malignancy or with solid organ transplantation, and (c) immune impairment in the bone marrow transplant patient. Appreciation of the specific clinical setting in which to consider these infections will be emphasized.

ISSN:0883-5993    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Immune deficiency states in children may be related to primary immunodeficiency syndromes or secondary disorders of the immune system. The secondary immunodeficiencies in children include human immunodeficiency virus-associated acquired immunodeficiency, as well as immunosuppression secondary to antineoplastic chemotherapeutic agents, bone marrow transplantation, and drugs given to prevent transplant rejection. This article discusses the common primary and secondary immunocompromised states of childhood, with emphasis on their attendant infectious, lym-phoproliferative, and neoplastic complications.

ISSN:0883-5993    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Opportunistic fungal infection is a common cause of serious morbidity and mortality in immunocompromised patients. These infections occur primarily in patients with chemotherapy-induced neutropenia, acquired immunodeficiency syndrome, or immunosuppression after solid organ or bone marrow transplantation. The most important opportunistic fungal pathogens includeCryptococcus neoformans, CandidaandAspergillusspecies, and the fungi that cause mucormycosis. Opportunistic pneumonia caused by previously unrecognized pathogens, such asFusarium, Penicillium,and the dematiaceous fungi, are increasingly reported. The clinical and radiologic features of opportunistic fungal pneumonia are highly variable and often nonspecific. Diagnosis requires knowledge of the various modes of presentation, radiologic manifestations, and epidemiology of these infections. Because many of these organisms can colonize the upper airway, sputum cultures are considered diagnostically unreliable. Instead, definitive diagnosis requires culture of the fungus from infected tissue or demonstration of the organism on microscopic examination.

ISSN:0883-5993    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Missed lung cancer is an important medicolegal issue and is the second leading cause for malpractice actions against radiologists. Contributing factors to overlooked lung cancer can be ascribed to observer performance, lesion characteristics, and technical considerations. Of these, errors related to observer performance are probably the most important. Missed lung cancer does not necessarily constitute malpractice, but lesions of high conspicuity are more likely to be associated with an adverse legal outcome. Multiple strategies have been advocated to reduce the frequency of missed lung cancer. Several studies have emphasized the importance of careful comparison of the current radiograph with one or more prior examinations.

ISSN:0883-5993    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Twenty-four patients (nine with squamous cell carcinoma, 14 with adenocarcinoma, and one with large cell carcinoma) underwent neoadjuvant therapy followed by surgical resection. The authors studied changes in tumor size, shape, and contrast enhancement on computed tomography (CT), and compared them with results of pathologic examination of surgical specimens. The size of tumors on CT was evaluated according to the criteria of the World Health Organization. Surgical specimens were evaluated histologically on the basis of the area of viable cancer cells. Of 14 patients considered to have a partial response on the basis of World Health Organization criteria, five had pathologic changes of complete response. After therapy, the residual tumors in these five patients showed irregular shapes with concave tumor margins on CT images and no enhancement. The authors found that CT size criteria tended to underestimate the therapeutic effect demonstrated by pathologic examination. On the basis of these results, the authors propose three CT criteria for complete response: 1) more than 50% size reduction, 2) a change in tumor morphologic features from round or oval to irregular after neoadjuvant therapy, and 3) disappearance of contrast enhancement.

ISSN:0883-5993    

出版商:OVID    

年代:1999

数据来源: OVID