Thoracic disease in the immunocompromised patient.

Thoracic disease in the HIV negative immunocompromised host is most frequently caused by infection. Patterns of involvement produced on the chest radiograph include (1) lobar or segmental consolidation, (2) nodules with rapid growth and/or cavitation, and (3) diffuse lung disease. The lung also may be directly involved by lymphoma, metastases, drug reactions, radiation pneumonitis, or nonspecific interstitial pneumonitis. The lung is a frequent target organ for opportunistic infections in AIDS patients, particularly of Pneumocystis carinii pneumonia and tuberculosis. Computed tomography may be particularly helpful in these patients in the detection of early disease and in the characterization of patterns and extent of involvement as well as complications.     

Thoracic disorders in the immunocompromised child

Immunodeficiencies in children may be caused by primary immunodeficiency syndromes or can result from secondary disorders of immune regulation. Thoracic complications in immunocompromised children are frequent and may vary according to the type of the immunodeficiency. Imaging plays a pivotal role in detection and distinction of the variety of sequelae. It is important for the radiologist to understand both the spectrum of pediatric immune disorders, and the mechanisms underlying these disorders.     

Abdominal imaging in the immunocompromised patient.

Abdominal and gastrointestinal disease may result in clinically important complications in immunocompromised patients. The major types of disease are opportunistic infections and immunodeficiency-associated neoplasms. A multimodality approach is often essential in the diagnosis and staging of these lesions. A combination of bacteriologic culture, endoscopy, barium studies, and cross-sectional imaging of the abdomen with computed tomography and sonography is required to assess the extent of the disease accurately.     

Lymphoma in the immunocompromised patient

The increased incidence of malignant lymphomas in patients with congenital or acquired immunodeficiency states is now well recognized. In recent years, acquired immunodeficiency syndrome (AIDS) related non-Hodgkin's lymphoma has accounted for a growing proportion of these aggressive neoplasms. This article reviews the radiographic features of lymphoma in AIDS and non-AIDS immunocompromised patients.     

Imaging manifestations of neck masses in the immunocompromised host

Human immunodeficiency virus (HIV) infection, haematological malignancy, and immunosuppression for transplantation and autoimmune disorders have led to a large increase in immunocompromised patients. Neck masses are relatively common in this patient group and include both opportunistic and severe manifestations of common infections, benign hyperplasia, and primary or secondary malignancies. Although biopsy may be necessary for definitive diagnosis, features on cross-sectional imaging may suggest a specific diagnosis or limit the differential diagnosis and facilitate optimal patient management. This article will review critical aspects of neck anatomy, illustrate the spectrum of imaging features, and discuss the interpretative pearls and pitfalls when evaluating neck masses in immunocompromised patients.     

Thoracic manifestations of neurofibromatosis-I

The intrathoracic manifestations of neurofibromatosis-I are protean and can, on occasion, mimic those of malignancy. Many of the intrathoracic findings are characteristic of the disease and can be expected to be present. Knowledge of the full spectrum of radiologic findings can thus be useful in preventing diagnostic error. Furthermore, an unexpected finding, such as rapid growth of a neural tumor, should be recognized as an atypical feature (suspicious for malignant degeneration) and result in further evaluation.     

Thoracic manifestations of aspergillosis

The fungus Aspergillus can cause a variety of pulmonary disorders. Allergic bronchopulmonary aspergillosis is characterized by eosinophilic pulmonary infiltrates, bronchiectasis and bronchial mucus plugs, and can progress to chronic pulmonary fibrosis. There are four additional variant forms of allergic bronchopulmonary aspergillosis, which may or may not be associated with aspergillus hypersensitivity. They are mucoid impaction of bronchi, pulmonary infiltrates with eosinophilia, bronchocentric granulomatosis, and extrinsic allergic alveolitis. Intracavitary aspergilloma (mycetoma, or fungus ball) is a noninvasive Aspergillus colonization of virtually any type of preexisting pulmonary cavity or cystic space. Invasive pulmonary aspergillosis is a serious, usually fatal infection in patients being treated with immunosuppressions or who have chronic (malignant or nonmalignant) debilitating disease. Diagnosis of Aspergillus-caused pulmonary disorders is based on a combination of clinical, laboratory, and radiographic findings, all of which should be known to the radiologist.     

小儿腹部Burkitt淋巴瘤结外侵犯的MSCT表现

目的：探讨儿童腹部Burkitt淋巴瘤结外侵犯的MSCT表现及其诊断价值。方法：回顾性分析本院22例经病理证实的Burkitt淋巴瘤的腹部MSCT资料,对其结外病变进行分类和影像学表现分析。结果：Burkitt淋巴瘤可侵犯腹盆腔的多个结外脏器,包括腹部实质脏器（8/22）和胃肠道（21/22）。病变多表现为轻度强化的密度均匀的实性肿物,出血、坏死少见,钙化罕见;常伴肠系膜及腹膜后多个肿大淋巴结、大网膜广泛增厚或腹腔积液,以回肠远端浸润型和胰腺多发结节型最多见。结论：Burkitt淋巴瘤常同时侵犯腹盆腔多个结外脏器,儿童Burkitt淋巴瘤腹部结外侵犯的MSCT表现有一定特征性。     

Thoracic lymphoma in AIDS

Over the last 4 years, we observed 122 patients with AIDS and 20 with AIDS-related lymphomas (ARL) in the chest. Eighteen of the latter were non-Hodgkin's forms, mostly high-grade and high-stage B-cell (Burkitt or Burkitt-like) types (16 cases.) This prevalence reflects the overall increase in neoplasms secondary to immunodepression, which is parallel to improved prevention and control of opportunistic infections. Of 20 ARLs, 5 (25%) presented thoracic lesions; in 4 of them the onset of the disease was localized in the chest. The incidence of such manifestations is higher than that reported in the literature. Moreover, radiological features are quite atypical relative to the "classical" signs of lymphoma in the general population, with predominant (60%) nodules or quickly-growing peripheral masses which may subsequently invade chest walls. Isolated nodal enlargement is also a possible finding, as well as pleural effusion. This pattern, though not pathognomonic, is highly suggestive--in HIV-positive patients--of ARL. In all the patients with pulmonary lymphoma CT demonstrated bilateral lesions--more than conventional X-rays--with morphologic and densitometric features which helped make the correct diagnosis. Moreover, CT was helpful in choosing the appropriate site for biopsy.     

Radiologic manifestations of esophageal lymphoma.

Eight cases of esophageal lymphoma are presented. Contiguous involvement of the distal esophagus and stomach with narrowing and/or nodularity was the most common esophageal abnormality. Other appearances noted were an ulcerated mass, multiple submucosal nodules, and a pattern simulating varices. The spectrum of radiologic appearances with esophageal lymphoma is similar to lymphomatous involvement in the remainder of the gastroinestinal tract.     

Respiratory infection in the AIDS and immunocompromised patient

Immunocompromised patients are susceptible to infections by a wide range of organisms. In the past several decades, AIDS epidemic, advances in the treatment of cancer, organ transplantation, and immunosuppressive therapy have resulted in large numbers of patients who develop abnormalities in their immune system. Moreover, mildly impaired host immunity as it occurs in chronic debilitating illness, diabetes mellitus, malnutrition, alcoholism, advanced age, prolonged corticosteroid administration, and chronic obstructive lung disease have also been regarded as predisposing factors of pulmonary infections. Imaging plays a crucial role in the detection and management of patients with pulmonary infectious diseases. When pulmonary infection is suspected, knowledge of the varied radiographic manifestations will narrow the differential diagnosis, helping to direct additional diagnostic measures, and serving as an ideal tool for follow-up examinations. Combination of pattern recognition with knowledge of the clinical setting is the best approach to pulmonary infection occurring in the immunocompromised patients.     

Respiratory infection in the AIDS and immunocompromised patient

Immunocompromised patients are susceptible to infections by a wide range of organisms. In the past several decades, AIDS epidemic, advances in the treatment of cancer, organ transplantation, and immunossupresive therapy have resulted in large numbers of patients who develop abnormalities in their immune system [1, 2, 3, 4]. Moreover, mildly impaired host immunity as it occurs in chronic debilitating illness, diabetes mellitus, malnutrition, alcoholism, advanced age, prolonged corticosteroid administration, and chronic obstructive lung disease have also been regarded as predisposing factors of pulmonary infections [5]. Imaging plays a crucial role in the detection and management of patients with pulmonary infectious diseases. When pulmonary infection is suspected, knowledge of the varied radiographic manifestations will narrow the differential diagnosis, helping to direct additional diagnostic measures, and serving as an ideal tool for follow-up examinations. Combination of pattern recognition with knowledge of the clinical setting is the best approach to pulmonary infection occurring in the immunocompromised patients.     

Pulmonary complications in the non-HIV immunocompromised patient

The incidence of non-HIV immunocompromised patients is increasing. This is primarily due to improved immunosuppressive regimes for autoimmune diseases and also increases in stem cell transplantation. Pulmonary complications are a major cause of morbidity and mortality in these patients. Imaging is frequently used to assess these complications and to streamline therapies, as microbiological and/or pathological diagnosis can often be difficult, invasive, or protracted. This review provides the reader with a structured approach to interpret the imaging findings and differentiate between different infective and non-infective complications in these patients.     

Thoracic lymphoma and AIDS]

During the past 4 years, 122 patients with AIDS and 20 with thoracic lymphoma associated to AIDS were observed. There were 18 cases of non-Hodgkin's lymphoma, mostly at a high grade and a high b-cell stage (Burkitt's or Burkitt-like lymphoma) (16 cases). This prevalence reflects the general increase in the number of neoplasms secondary to immunosuppression, which goes along with the improvement of prevention and the control of opportunistic infections. Out of these 20 lymphomas in AIDS, 5 (25%) produced thoracic lesions; in 4 cases, the initial site of the disease was in a thoracic site. The frequency of such expressions is greater that reported in the literature. The radiological appearances are atypical relative to the classical signs of lymphoma in the general population, with predominantly nodular forms (60%) or peripheral, fast-growing masses that are likely to invade the thoracic wall. Isolate lymph node invasion is possible, as well as pleural effusion. Though not pathognomonic, this appearance is highly suggestive of lymphoma in AIDS (LDS) in HIV-positive patients. In all patients with pulmonary lymphoma, CT showed bilateral lesions in a greater number than plain radiography had shown, with morphological and CT appearances that allowed a correct approach of the diagnosis and an appropriate choice of the site of biopsy.     

Diffuse lung disease in the immunocompromised non-HIV patient

Physicians are encountering an increasing number of patients with various levels of immunosuppression, such as patients with AIDS, transplant recipients, patients on immunosuppressive therapy, and those with congenital immune defects and malignancy. This results in a greater diagnostic dilemma for the medical community because of the significant increased risk of opportunistic infections and noninfectious complications, as well as a more aggressive clinical course with typical pathogens. [figure: see text] Furthermore, it is not just the pathogens that are changing but also their clinical and radiographic presentations. The radiologist has a large role in not only detecting the presence of disease but also in narrowing the differential possibilities. This can be an overwhelming task given the wide variety of presentations of diseases on radiographs. However, by understanding the level and degree of the patient's immunosuppression, the radiologist may anticipate the most likely pulmonary complications. By using the radiographic morphology, distribution, and temporal evolution of the abnormalities, a manageable differential diagnosis can be created for referring clinicians.     

Thoracic manifestations of collagen vascular diseases

Collagen vascular diseases are a diverse group of immunologically mediated systemic disorders that often lead to thoracic changes. The collagen vascular diseases that most commonly involve the lung are rheumatoid arthritis, progressive systemic sclerosis, systemic lupus erythematosus, polymyositis and dermatomyositis, mixed connective tissue disease, and Sj?gren syndrome. Interstitial lung disease and pulmonary arterial hypertension are the main causes of mortality and morbidity among patients with collagen vascular diseases. Given the broad spectrum of possible thoracic manifestations and the varying frequency with which different interstitial lung diseases occur, the interpretation of thoracic images obtained in patients with collagen vascular diseases can be challenging. The task may be more difficult in the presence of treatment-related complications such as drug toxicity and infections, which are common in this group of patients. Although chest radiography is most often used for screening and monitoring of thoracic alterations, high-resolution computed tomography can provide additional information about lung involvement in collagen vascular diseases and may be especially helpful for differentiating specific disease patterns in the lung. General knowledge about the manifestations of thoracic involvement in collagen vascular diseases allows radiologists to provide better guidance for treatment and follow-up of these patients.     

Radiographic manifestations of Burkitt's lymphoma in American patients.

Radiographic manifestations of Burkitt's lymphoma in 40 American patients are presented. Pleural effusions were the most common intrathoracic abnormality and were correlated with abdominal ascites more often than with intrathoracic tumor. Tumor involved bone in four patients had intrinsic bowel involvement; nine instances were in the ileum. Intrinsic renal tumor was seen in only two patients. Both ultrasound and computed tomography were useful.