Illustration of a number of atypical computed tomography manifestations of active pulmonary tuberculosis.

Tuberculosis is a serious public health challenge facing mankind and one of the top ten causes of death. Diagnostic imaging plays an important role, particularly for the diagnosis and treatment planning of tuberculosis patients with negative microbiology results. This article illustrates a number of atypical computed tomography (CT) appearances of pulmonary tuberculosis (PTB), including (I) clustered micronodules (CMNs) sign; (II) reversed halo sign (RHS); (III) tuberculous pneumatocele; (IV) hematogenously disseminated PTB with predominantly diffuse ground glass opacity manifestation; (V) hematogenously disseminated PTB with randomly distributed non-miliary nodules; (VI) PTB changes occur on the background of emphysema or honeycomb changes of interstitial pneumonia; and (VII) PTB manifesting as organizing pneumonia. While the overall incidence of PTB is decreasing globally, the incidence of atypical manifestations of tuberculosis is increasing. A good understanding of the atypical CT imaging changes of active PTB shall help the diagnosis and differential diagnosis of PTB in clinical practice.

[Quantitative comparison of idiopathic interstitial pneumonias on high-resolution computed tomographic findings].

OBJECTIVE: To analyze the high-resolution computed tomographic (HRCT) findings of IPF (interstitial pulmonary fibrosis), NSIP (nonspecific interstitial pneumonia) and COP (cryptogenic organizing pneumonia) retrospectively through quantification methods and to explore their distinguishing features. METHODS: Observers with no prior knowledge of the diagnosis evaluated the frequency, extent and distribution of various thin-section CT findings in 29 males and 17 females. The mean age was 50 ± 10 years old (range: 25 - 76). They had a histological diagnosis of IPF (n = 19), nonspecific interstitial pneumonia (NSIP) (n = 14) and cryptogenic organizing pneumonia (COP) (n = 13). RESULTS: Ground-glass opacity, thickening of bronchovascular bundles and interlobular septal thickening were frequent features of IPF and NSIP. The frequency and extent of honeycombing and bronchiolectasis were more found in IPF than in NSIP and COP (P < 0.05). The frequency and extent of air space consolidation were more found in COP than IPF (P < 0.05). There were more number of segments with traction bronchiectasis and less extent of air space consolidation in IPF than NSIP and COP. The number of segments with traction bronchiectasis was less in NSIP than that of IPF and COP. CONCLUSION: The various subtypes of idiopathic interstitial pneumonias often have the distinguishing characteristics easily identified on HRCT. Bronchiolectasis and honeycombing are valuable features for IPF; air space consolidation is a valuable feature for COP. The features of NSIP are also found in both IPF and COP so that additional features are required for both.

Clinical features of pneumonia caused by 2009 influenza A(H1N1) virus in Beijing, China.

BACKGROUND: Data on symptoms and radiographic changes in patients with pandemic 2009 influenza A(H1N1) (A[H1N1]) pneumonia during convalescence have not been reported. METHODS: During October 26, 2009, and January 23, 2010, adult patients with pneumonia with laboratory-confirmed or clinically suspected A(H1N1) infections were observed for clinical characteristics, high-resolution chest CT scan, and lung function test changes during acute and 3-month convalescent phases. RESULTS: Of the 65 case subjects, the median age was 41 (interquartile range [IQR], 28-57) years, 60.0% were men, and 55.4% had at least one underlying medical condition. Sixty-two patients started oseltamivir therapy within a median of 5 (IQR, 4-6) days from the onset of illness, and 31 received IV corticosteroids. ARDS developed in 33 patients, and 24 were treated initially with noninvasive positive pressure ventilation (NPPV). In this group, NPPV was successful in 13 patients (54.2%). Nine patients died at a median of 16 (IQR, 10-24) days after onset of illness. Multivariate Cox regression identified two independent risk factors for death: progressive dyspnea after resolution of fever (relative risk, 5.852; 95% CI, 1.395-24.541; P = .016) and a higher APACHE (Acute Physiology and Chronic Health Evaluation) II score on presentation (relative risk for each point, 1.312; 95% CI, 1.140-1.511; P < .001). At 3-month follow-up of survivors with A(H1N1), ground-glass opacities were still present, although diminished, in 85.7%, and diffusing capacity for carbon monoxide was mildly reduced in 61.5%. CONCLUSIONS: Ground-glass opacities and decreased diffusing capacity were the main abnormalities observed at 3-month follow-up of survivors of A(H1N1).