[Cryptogenic organizing pneumonia]. / Pneumopathie organisée cryptogénique.

INTRODUCTION: Organizing pneumonia is a particular type of inflammatory reaction of the lung which gives rise to a clinico-pathological syndrome. It is called "secondary" when a cause such as an infection, a drug toxicity, or a connective tissue disease can be identified, or "cryptogenic" when no cause is identified. The clinical picture is usually characterized by the subacute onset of fever, fatigue, cough and dyspnea, with multiple subpleural areas of consolidation on thoracic imaging. STATE OF THE ART: Organizing pneumonia is characterised by the presence of buds of endoalveolar connective tissue. These result from an injury to the alveolar epithelium, followed by the deposition of fibrin in the alveolar spaces, and the migration of fibroblasts which produce a myxoid endoalveolar matrix. A remarkable feature of organizing pneumonia is the complete disappearance of these endoalveolar buds with corticosteroid treatment, in sharp contrast with what is seen in pulmonary fibrosis. The clinical response to corticosteroids is usually prompt and excellent. Relapses are frequent but usually benign. PERSPECTIVES AND CONCLUSION: As the clinical, imaging and pathological characteristics of organizing pneumonia are now well established, many questions remain unanswered, such as the mechanisms involved in the complete reversibility of the pulmonary lesions, and the role of steroid-sparing treatments such as immunomodulatory macrolides.

[Lung volume reduction (LVR) in severe emphysema: a multidisciplinary approach]. / Réduction de volume pulmonaire dans l'emphysème sévère: importance d'une prise en charge multidisciplinaire.

Most cases of emphysema are managed conservatively. However, in severe symptomatic emphysema associated with hyperinflation, lung volume reduction (LVR) may be proposed to improve dyspnea, exercice capacity, pulmonary functions, walk distance and to decrease long-term mortality. LVR may be achieved either surgically (LVRS) or endoscopically (EVLR by valves or coils) according to specific clinical criteria. Currently, the optimal approach is discussed in a multidisciplinary setting. The latter permits a personalized evaluation the patient's clinical status and allows the best possible therapeutic intervention to be proposed to the patient.

[Idiopathic pulmonary fibrosis: recent diagnostic and therapeutic advances]. / Fibrose pulmonaire idiopathique: nouveautés diagnostiques et thérapeutiques.

Idiopathic pulmonary fibrosis (IPF) is the most frequent of the idiopathic interstitial pneumonias. It is a progressive disorderwith a poor prognosis. Its diagnosis requires the careful exclusion of potential causes, and a pattern of usual interstitial pneumonia at high-resolution computed tomography or video-assisted surgical lung biopsy. Several recent randomized trials have profoundly modified the therapeutic management of IPF. The combination of prednisone and azathioprine, often prescribed until recently, has been shown to be harmful and is no longer indicated. N-acetylcystein, also used in the past decade, failed to show an efficacy. However, two new antifibrotic drugs, pirfenidone and nintedanib, have for the first time proven effective in slowing disease progression.

Imaging of the non-traumatic brachial plexus.

The first line imaging of the non-traumatic brachial plexus is by MRI. Knowledge of the anatomy and commonest variants is essential. Three Tesla imaging offers the possibility of 3D isotropic sequences with excellent spatial and contrast enhancement resolutions, which leads to time saving and quality boosting. The most commonly seen conditions are benign tumor lesions and radiation damage. Gadolinium is required to assess inflammatory or tumour plexopathy. MRI data should be correlated with FDG-PET if tumor recurrence is suspected.

[Subacute neuropathy, multiple cancers, and Gougerot-Sjögren syndrome: contribution of anti-Hu antibody]. / Neuropathie subaiguë, cancers multiples et syndrome de Gougerot-Sjögren: intérêt des anticorps anti-Hu.

We report the case of a patient presenting a subacute, predominantly sensory neuropathy. The work up revealed a Sjögren's syndrome and a breast carcinoma. The presence of anti-Hu antibodies, identified by Western Blot using purified recombinant HuD protein, and the absence of the Hu antigen in the breast carcinoma ruled out the responsibility of the Sjögren's syndrome or breast carcinoma. In this context, the most likely diagnosis was a subacute neuropathy associated with small cell lung cancer, which was indeed discovered 3 years later.

Alveolar lymphocytosis in patients with chronic uveitis: relationship to sarcoidosis.

Bronchoalveolar lavage (BAL) is frequently performed in patients with suspected ocular sarcoidosis. This study describes the immunogenetical, immunological, radiological, and functional features of a subclinical alveolar lymphocytosis unrelated to sarcoidosis in patients with chronic uveitis. Two hundred and ten patients with chronic uveitis of unknown origin, who underwent fiber-optic bronchoscopy with BAL as part of a prospective protocol over a three-year period, were evaluable for retrospective analysis. Sixty-five patients had alveolar lymphocytosis: Sarcoidosis was diagnosed in 13 (6%) patients, whereas alveolar lymphocytosis was considered unrelated to sarcoidosis in 52 (25%). Alveolar lymphocytosis unrelated to sarcoidosis was not associated with radiologically detectable interstitial lung disease or pulmonary function impairment. CD4/CD8 lymphocyte ratio was 3.7 +/- 3.0. Total cell count, total lymphocyte, and CD4 lymphocyte percentage were significantly lower when compared with sarcoidosis-related alveolitis (129,000 +/- 80,000 vs. 218,000 +/- 117,000, p <0.05; 33.1% +/- 13.2 vs. 39.7% +/- 13.2, p <0.05; and 54.3% +/- 18.2 vs. 65.4% +/- 10.1, p <0.05, respectively). Patients with alveolar lymphocytosis unrelated to sarcoidosis were older (47.8 +/- 17.7 years vs. 42.7 +/- 14.2 years, p <0.05) and more likely to carry the HLA-B51 allele (19.7% vs. 7.1%, p <0.01) than patients with chronic uveitis without alveolar lymphocytosis. They did not appear to be at risk of developing clinically apparent interstitial lung disease on followup. We conclude that alveolar lymphocytosis is frequently observed in patients with chronic uveitis. It is generally unrelated to sarcoidosis and may then be associated with a distinctive immunogenetic phenotype.

Pancreatic involvement in von Hippel-Lindau disease. The Groupe Francophone d'Etude de la Maladie de von Hippel-Lindau.

BACKGROUND & AIMS: Pancreatic involvement in von Hippel-Lindau (VHL) disease, a genetic disorder with a dominant mode of inheritance affecting various organs, has rarely been studied. We assessed the prevalence, type of lesions, natural history, and impact of pancreatic involvement in patients with VHL. METHODS: A total of 158 consecutive patients from 94 families with VHL disease were studied in a prospective French collaborative study. All patients underwent systematic screening for VHL lesions, including computerized tomography (CT) scanning of the pancreas reviewed by an experienced radiologist. Clinical data, investigations, and treatments performed were also reviewed. RESULTS: Pancreatic involvement was observed in 122 patients (77.2%) and included true cysts (91.1%), serous cystadenomas (12.3%), neuroendocrine tumors (12.3%), or combined lesions (11.5%). The pancreas was the only organ affected in 7.6% of patients. Patients with pancreatic lesions had fewer pheochromocytomas than those without (14/122 vs. 16/36; P<0.0001), and patients with neuroendocrine pancreatic tumors had renal involvement less often than those without (8/99 vs. 6/20; P = 0.013). None of the patients with neuroendocrine tumors had symptoms of hormonal hypersecretion. Pancreatic lesions evolved in half of patients but required specific treatment in only 10 (8.2%) when they were symptomatic or for the resection of large neuroendocrine tumors. CONCLUSIONS: Pancreatic involvement is seen in most patients with VHL disease. Although symptoms are rare, specific treatment of pancreatic lesions is required in selected patients, mainly those with neuroendocrine tumors.

Iron oxide-enhanced MR lymphography: initial experience.

The detection of nodal metastases is of utmost importance in oncologic imaging. Ultrasmall superparamagnetic iron oxide particles (USPIO) are novel contrast agents specifically developed for MR lymphography. After intravenous administration, they are taken up by the macrophages of the lymph nodes, where they accumulate. They reduce the signal intensity (SI) of normally functioning nodes on postcontrast T2-and T2*-weighted images through the magnetic susceptibility effects on iron oxide. Metastatic nodes, in which macrophages are replaced by tumor cells, show no significant change in SI on postcontrast T2-and T2*-weighted images. Early clinical experience suggests that USPIO-enhanced MR lymphography improves the sensitivity and specificity for the detection of nodal metastases. It also suggests that micrometastases could be detected in normal-sized nodes. This article reviews the physiochemical properties of USPIO contrast agents, their enhancement patterns, and early clinical experience.

CT of parenchymal and bronchial tuberculosis.

Tuberculosis (TB) remains a common disease in the World. Its incidence has risen steadily since 1985, despite a preexisting continuous decreasing of its frequency due to an effective chemotherapy. Nonwhite people, socioeconomically disadvantaged, chronically debilitated groups and AIDS patients are the most concerned. Chest radiography remains the first imaging modality to evaluate TB. Widely radiographic appearances can be encountered, including normal chest X-ray. CT can be useful in all stages of the disease, particularly when clinical and radiological findings are in disagreement and/or when imaging findings are equivocal. CT should be proposed at the end of an effective antituberculous treatment to better subsequently detect fine lesions suggestive of reactivation TB.

[Computed tomography in 2000: technique, expected progress, limitations, indications]. / La tomodensitom¿etrie en l'an 2000. Technique, progrès attendus, limites, indications.

Computed tomography (CT) is today a fundamental technique for thoracic imaging, a logical direct extension of the standard chest x-ray. Since the early 90s, volume-acquisition CT has greatly improved the performance of the conventional technique. After replacing lung and bronchial tomography, the technique has greatly contributed to the reduction in the number of diagnostic conventional angiographies. Certain decisional algorithms have been totally changed, particularly for the diagnosis of pulmonary embolism. In addition, technological advances offer new perspectives, particularly in the field of morphofunctional imaging. There are still many indications for CT and new applications can be expected. Possible drawbacks related to radiation dose and injection of contrast agents must be kept in mind.

[CT angiography of the pulmonary arteries]. / Angioscanographie des vaisseaux pulmonaires.

CT angiography of the pulmonary arteries recently appeared as an alternative method potentially useful in the diagnosis of pulmonary embolism. Technical aspects, normal aspects and variants, diagnostic criteria of pulmonary embolism as well as potential pitfalls are successively described. The accuracy of CT angiography compared with pulmonary angiography and V-Q scintigraphy has been evaluated in several studies. The method appears accurate for the diagnosis of pulmonary embolism at the level of segmental arteries. The signification of more distal embolism remains however controversed. CT angiography seems to play a major role in the diagnosis of pulmonary embolism, as well as echo-doppler of the legs.

Contrast-enhanced helical CT for pulmonary embolism detection: inter- and intraobserver agreement among radiologists with variable experience.

OBJECTIVE: The objective of this study was to evaluate inter- and intraobserver agreement in the diagnosis of central pulmonary embolism using contrast-enhanced helical CT among observers with variable experience in the interpretation of pulmonary CT angiograms. MATERIALS AND METHODS: Helical CT angiograms of 60 patients clinically suspected of having pulmonary embolism were analyzed retrospectively and independently by two chest radiologists, one cardiovascular radiologist, and three general radiologists. The films were rated a second time by the chest radiologists to assess intraobserver variability. Findings for pulmonary embolism were categorized as positive, negative, or indeterminate at the main, lobar, and segmental pulmonary artery levels. RESULTS: The observers interpreted 19-21 CT angiograms as positive for pulmonary embolism (mean, 19.7) and one to six as indeterminate (mean, 3.2). Agreement occurred among all observers in 50 patients (83.3%), among five observers in six patients (10.0%), among four observers in three patients (5.0%), and among three observers in one patient (1.7%). Interobserver agreement was very good (kappa, .85) for the diagnosis of pulmonary embolism on a per-patient basis. Agreement on a per-artery basis for all arteries was moderate (66%; kappa, .56); for lobar arteries was good (83%; kappa, .75); and for segmental arteries was moderate (57%; kappa, .47). Mean intraobserver agreement on a per-patient basis was very good (93%; kappa, .87). CONCLUSION: Inter- and intraobserver agreement in the diagnosis of pulmonary embolism with helical CT is very good despite a wide variety of experience among radiologists.

[Thoracic infections in immunocompetent patients. The contribution of computed tomography]. / Infections thoraciques chez le sujet immunocompétent. Apport de la tomodensitométrie.

Chest X-Ray is the most accurate method of imaging for infectious diseases in an immunocompetent patient. Computed tomography (CT) may be useful in certain circumstances, particularly in case of atypical findings at the time of diagnosis or in case of complications. CT helps to detect and perform a complete study of the lesions, some aspects being very suggestive of a diagnosis, as in post-primary active tuberculosis. CT may also detect an unknown underlying etiology. Multiplanar reformations with helical CT can be useful for example in case of empyema. In case of non tuberculous bacterial infections, CT is mainly recommended when abscess and empyema are difficult to differentiate or in case of pleural complications with possible percutaneous treatment. In case of tuberculosis, CT may be indicated when clinical and chest X-Ray findings are discordant, in case of mediastinal adenopathies, when reactivation is suspected or in case of complications as hemoptysis. A baseline CT examination could be proposed at the end of a specific treatment to facilitate the diagnosis of reactivation tuberculosis. A nontuberculous mycobacterial infection should finally be suspected in front of peculiar CT findings.

Association of small cell lung cancer and the anti-Hu paraneoplastic syndrome: radiographic and CT findings.

OBJECTIVE: The anti-Hu syndrome (bearing the name of the patient in whom the antibody was first discovered) is characterized by a paraneoplastic encephalomyelitis or sensory neuronopathy and the presence of a specific antibody in the serum or CSF and is associated with lung cancer in most patients who have the syndrome. The objective of this study was to determine the relative merits of chest radiography and CT in the imaging of patients with the anti-Hu syndrome. MATERIALS AND METHODS: Chest radiographic and CT findings of 11 patients with anti-Hu syndrome were reviewed and correlated with results of bronchoscopy, surgery, or autopsy. RESULTS: Ten of the 11 patients had small cell lung cancer; in the remaining patient, no cancer was found. Small cell lung cancer was first revealed on radiographs in one patient and solely on CT in the remaining nine patients with small cell lung cancer. In six of these nine patients, the initial CT findings were positive for lung cancer. Tumor was found on follow-up CT in 4-8 months when initial CT findings were negative. Mediastinal adenopathy was present in all 10 cancer patients. Hilar adenopathy was present in four. Parenchymal involvement was seen in three of the 10 patients with cancer. In two patients, the only CT finding of small cell lung cancer was one mediastinal lymph node of 10 mm in each patient. CONCLUSION: Chest CT should be recommended for patients with anti-Hu syndrome, even when chest radiographic findings are interpreted as normal.

Pyogenic bacterial pneumonia in human immunodeficiency virus-infected inpatients: a clinical, radiological, microbiological, and epidemiological study.

We prospectively studied features of pyogenic bacterial pneumonia in 263 consecutive human immunodeficiency virus-infected inpatients over a 6-month study period. Risk factors for bacterial pneumonia were examined by a case-control study that included 33 cases who presented with at least one episode of bacterial pneumonia and 80 controls without bacterial pneumonia. The estimated cumulative incidence of bacterial pneumonia per year was 12.5 cases per 100 inpatients (95% confidence interval [CI], 8.8-17.2). The 38 episodes of bacterial pneumonia that occurred in the 33 inpatients were mainly unilateral, but 32 episodes were patchy lobar or diffuse infiltrates. Microbiological etiologies were obtained in 33 of the 38 episodes of bacterial pneumonia. Thirty-seven pathogens were identified, including Streptococcus pneumoniae (16, of which 12 had a decreased susceptibility to penicillin), Haemophilus influenzae (6), and Pseudomonas aeruginosa (6). The risk factors for bacterial pneumonia that were identified after logistic regression included prior sinusitis within 1 month before admission (odds ratio [OR], 3.2; 95% CI, 1.1-9.1) and prior bacterial infection of the lower respiratory tract within 6 months before admission (OR, 3.1; 95% CI, 1.1-8.3).

Congenital anomalies of tracheobronchial branching patterns: spiral CT aspects in adults.

Congenital abnormalities of the bronchi have been classically described with chest X-rays, conventional tomography, bronchography, CT and MR imaging. Recently, the capacity of spiral CT to explore a complete volume with no gap and excellent multiplanar reformations has been emphasized. The contribution of this technique to the analysis of congenital anomalies of tracheobronchial branching patterns encountered in adult patients is illustrated. Agenesis, aplasia, and hypoplasia are discussed, followed by bronchial atresia and abnormalities of bronchial divisions. In most cases spiral CT permits a full and correct evaluation of the malformation as well as its associated anomalies. It appears therefore to be the preferable technique for studying such anomalies of the tracheobronchial tree. Moreover, knowledge of CT aspects of the main congenital bronchial abnormalities along with complete visualization of the tracheobronchial tree will probably lead to detection of more incidental anomalies.