Imaging of community-acquired pneumonia: Roles of imaging examinations, imaging diagnosis of specific pathogens and discrimination from noninfectious diseases.

This article reviews roles of imaging examinations in the management of community-acquired pneumonia (CAP), imaging diagnosis of specific CAP and discrimination between CAP and noninfectious diseases. Chest radiography is usually enough to confirm the diagnosis of CAP, whereas computed tomography is required to suggest specific pathogens and to discriminate from noninfectious diseases. Mycoplasma pneumoniae pneumonia, tuberculosis, Pneumocystis jirovecii pneumonia and some cases of viral pneumonia sometimes show specific imaging findings. Peribronchial nodules, especially tree-in-bud appearance, are fairly specific for infection. Evidences of organization, such as concavity of the opacities, traction bronchiectasis, visualization of air bronchograms over the entire length of the bronchi, or mild parenchymal distortion are suggestive of organizing pneumonia. We will introduce tips to effectively make use of imaging examinations in the management of CAP.

Localized mucinous bronchioloalveolar carcinoma of the lung: thin-section computed tomography and fluorodeoxyglucose positron emission tomography findings.

PURPOSE: The aim of this study was to evaluate thinsection computed tomography (CT) and fluorodeoxyglucose positron emission tomography (FDG-PET) findings of localized pulmonary mucinous bronchioloalveolar carcinomas (BACs). METHODS AND MATERIALS: From February 2000 to February 2009, there were seven patients with pulmonary localized mucinous BACs that were pathologically confirmed in the surgical specimens. Their CT findings were assessed regarding location, extent (percent) of groundglass opacity (GGO), margin characteristics, and the presence of air-containing spaces and contractive changes. We evaluated the presence of the "angiogram sign" in the patients who underwent enhanced CT. The maximum standardized uptake value (SUVmax) on FDG-PET was measured in four cases. RESULTS: All tumors were located in the lower lobes. The percentages of GGOs ranged from 0% to 70% (average 20%). The tumor margins were well defined in five cases and ill-defined in two cases. Air-containing spaces were seen in all cases. Evidence of contractive change was seen in two of the seven cases. The angiogram sign was identified in one of five patients who underwent enhanced CT. The SUVmax on FDG-PET ranged from 0.93 to 1.97 (mean 1.53). CONCLUSION: The imaging features of localized mucinous BACs include solid or partly solid attenuation, the presence of air-containing spaces, lack of contractive changes, and lower lobe predominance. Additionally, the SUVmax is markedly low on FDG-PET.

Chlamydia pneumoniae: comparison with findings of Mycoplasma pneumoniae and Streptococcus pneumoniae at thin-section CT.

PURPOSE: To retrospectively compare thin-section computed tomographic (CT) findings of Chlamydia pneumoniae pneumonia with those of Streptococcus pneumoniae pneumonia and Mycoplasma pneumoniae pneumonia. MATERIALS AND METHODS: Institutional review board and patient informed consent were not required. Twenty-four patients with C pneumoniae pneumonia (17 men, seven women; age range, 19-89 years) underwent thin-section CT; 41 patients with S pneumoniae pneumonia (28 men, 13 women; age range, 19-91 years) and 30 patients with M pneumoniae pneumonia (20 men, 10 women; age range, 16-67 years) were also enrolled. Thin-section CT scans of each patient were retrospectively and independently assessed by two chest radiologists for consolidation, ground-glass opacity (GGO), bronchovascular bundle thickening, nodules, pleural effusion, lymphadenopathy, reticular or linear opacity, airway dilatation, pulmonary emphysema, and bilateral lung involvement. Consensus was reached for disagreements. The frequency of each finding was compared among the three types of pneumonia by using the chi2 test. RESULTS: For C pneumoniae pneumonia, CT demonstrated consolidation in 20 patients, GGO in 13, bronchovascular bundle thickening in 17, nodules in 18, pleural effusion in six, lymphadenopathy in eight, reticular or linear opacity in 15, airway dilatation in nine, pulmonary emphysema in 11, and bilateral lung involvement in 12. Bronchovascular bundle thickening (P = .022) and airway dilatation (P = .034) were significantly more frequent in patients with C pneumoniae pneumonia than in those with S pneumoniae pneumonia. Reticular or linear opacity (P = .017), airway dilatation (P = .016), and associated pulmonary emphysema (P = .003) were significantly more frequent in patients with C pneumoniae pneumonia than in those with M pneumoniae pneumonia. CONCLUSION: C pneumoniae pneumonia demonstrates a wide spectrum of thin-section CT findings that are similar to those of S pneumoniae pneumonia and M pneumoniae pneumonia; airway dilatation and bronchovascular thickening were significantly more frequent in patients with C pneumoniae pneumonia.

Air-containing space in lung adenocarcinoma: high-resolution computed tomography findings.

OBJECTIVE: To disclose imaging features of air-containing spaces other than air bronchograms in lung adenocarcinoma on high-resolution computed tomography (HRCT). MATERIALS AND METHODS: We retrospectively reviewed HRCT scans of 42 consecutive patients with surgically proved lung adenocarcinoma correlating with pathologic specimens. RESULTS: Air-containing spaces were seen in 17 (40%) of cases on HRCT. The air-containing spaces appeared as multiple air densities (16 cases [94%]) with variable shapes and had a relatively larger size than that of air bronchograms. Internal septi were often noted (11 cases [65%]). CONCLUSION: Our results demonstrate that multiplicity, larger diameter, and internal septi are the features of air-containing spaces. These findings could be a key to the definitive diagnosis of lung adenocarcinoma, distinguishing it from the mimics such as organizing pneumonia, tuberculoma, or malignant lymphoma.

[Refractory non-small-cell lung cancer responding to combination chemotherapy with gemcitabine and cisplatin].

The patient was a 60-year-old female with adenocarcinoma of the lung. An effective radiation therapy was performed for cervical lymph node metastases found 19 months after the operation. A right adrenal metastasis and abdominal paraaortic lymph node metastases were detected 11 months later, and chemotherapy with cisplatin (CDDP) was administered. Although a temporary partial response was obtained, the metastatic lesion was refractory to CDDP. The patient was treated with gemcitabine (GEM) and CDDP, which resulted in near complete response continued for 3 months. The combination therapy of GEM and CDDP may be effective for recurrent non-small-cell lung cancer refractory to other regimens.

Bronchiolitis obliterans organizing pneumonia after tangential beam irradiation to the breast: discrimination from radiation pneumonitis.

We report a case of bronchiolitis obliterans organizing pneumonia (BOOP) secondary to tangential beam irradiation to the breast, which occurred seven months after the completion of radiotherapy. Although radiation pneumonitis is an alternative consideration, BOOP could be differentiated from it by its relatively late onset and extensive distribution, which did not respect the radiation field. This disease should always be kept in mind in patients with a history of tangential beam irradiation to the breast.