Acta Radiologica http://acr.sagepub.com/

Pulmonary cryptococcosis: comparison of CT findings in immunocompetent and immunocompromised patients Li-xuan Xie, You-san Chen, Shi-yuan Liu and Yu-xin Shi Acta Radiol published online 22 April 2014 DOI: 10.1177/0284185114529105 The online version of this article can be found at: http://acr.sagepub.com/content/early/2014/04/22/0284185114529105

Published by: http://www.sagepublications.com

On behalf of: Nordic Society of Medical Radiology

Additional services and information for Acta Radiologica can be found at: Email Alerts: http://acr.sagepub.com/cgi/alerts Subscriptions: http://acr.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav

>> OnlineFirst Version of Record - Apr 22, 2014 What is This?

Downloaded from acr.sagepub.com at Abant Izzet Baysal University on May 18, 2014

XML Template (2014) [16.4.2014–3:11pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/ACRJ/Vol00000/140049/APPFile/SG-ACRJ140049.3d

(ACR)

[1–7] [PREPRINTER stage]

Acta Radiol OnlineFirst, published on April 22, 2014 as doi:10.1177/0284185114529105

Original Article

Pulmonary cryptococcosis: comparison of CT findings in immunocompetent and immunocompromised patients

Acta Radiologica 0(0) 1–7 ! The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0284185114529105 acr.sagepub.com

Li-xuan Xie1, You-san Chen2, Shi-yuan Liu3 and Yu-xin Shi4

Abstract Background: Computed tomography (CT) findings in patients with pulmonary cryptococcosis have been reported, however, many reports were limited by the small number of patients, and not taken into account the distinction between immunocompetent and immunocompromised patients. Purpose: To retrospectively evaluate thoracic CT findings in patients with pulmonary cryptococcosis whose immune status ranged from normal to severely compromised, and determine characteristic imaging features of pulmonary cryptococcosis between patients with different immune status. Material and Methods: CT scan findings of 29 immunocompetent and 43 immunocompromised patients with clinically proven pulmonary cryptococcosis were reviewed retrospectively. Different patterns of CT scan abnormalities between immunocompromised and immunocompetent patients, AIDS and non-AIDS immunocompromised patients were compared by Fisher’s exact test. Results: Pulmonary nodules/masses, either solitary or multiple, were the most common CT finding, present in 65 (90.3%) of the 72 patients; associated findings included CT halo sign (n ¼ 24), cavitation (n ¼ 23), and air bronchogram (n ¼ 17). Areas of consolidation (n ¼ 14), areas of GGO (n ¼ 13), linear opacities (n ¼ 11), lymphadenopathy (n ¼ 5), and pleural effusion (n ¼ 8) were uncommon. The parenchymal abnormalities were peripherally located in 47 (65.2%) of the cases. Cavitations within nodules/masses were more frequently present in immunocompromised patients than in immunocompetent patients (P ¼ 0.009), and in AIDS patients than in non-AIDS immunocompromised patients (P ¼ 0.002). Air bronchograms within nodules/masses were more frequent present in immunocompetent patients than in immunocompromised patients (P ¼ 0.005). Nodules/masses with halo sign were less frequent in AIDS patients than those in non-AIDS immunocompromised patients (P ¼ 0.027). Conclusion: Pulmonary cryptococcosis should be considered in the differential diagnosis of solitary or multiple pulmonary nodules. Cavitations within nodules/masses were more commonly seen in immunocompromised patients, especially AIDS patients, while air bronchograms were more commonly seen in immunocompetent patients.

Keywords Pulmonary, infection, cryptococcosis, immunology, tomography, X-ray, computed Date received: 15 July 2013; accepted: 27 February 2014

Introduction Cryptococcosis is a systemic mycosis caused by two species of the encapsulated basidiomycetes, Cryptococcus neoformans and C. gattii, which, respectively, cause infections in both immunocompromised individuals and immunocompetent hosts. The infection is usually predisposed by defective cellular immune function. Immunosuppressed individuals are usually susceptible to cryptococcosis, including AIDS, diabetes

1 Department of Nuclear Medicine, Wuhan General Hospital of CPLA Guangzhou Military Command, Wuhan, PR China 2 Department of Radiology, Wuhan General Hospital of CPLA Guangzhou Military Command, Wuhan, PR China 3 Department of Radiology, Shanghai Changzheng Hospital Affiliated to the Second Military Medical University, Shanghai, PR China 4 Department of Radiology, Public Health Clinical Center Affiliated to Fudan University, Shanghai, PR China

Corresponding author: Li-xuan Xie, Department of Nuclear Medicine, Wuhan General Hospital of CPLA Guanghzhou Military Command, Wuhan 430070, PR China. Email: [email protected]

Downloaded from acr.sagepub.com at Abant Izzet Baysal University on May 18, 2014

XML Template (2014) [16.4.2014–3:11pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/ACRJ/Vol00000/140049/APPFile/SG-ACRJ140049.3d

(ACR)

[1–7] [PREPRINTER stage]

2

Acta Radiologica 0(0)

mellitus, Hodgkin’s disease, and systemic lupus erythematosus (SLE) patients, or those who receive corticosteroids or other immunosuppressive therapies (1,2). With HIV becoming more epidemic, more than 80% cases of cryptococcosis worldwide have been associated with HIV infection, which is the main reason why the incidence of cryptococcosis has increased dramatically in the last two decades (3). The respiratory tract is thought to be the entry site and the organ most frequently involved when cryptococcal infection develops (4). Although the radiographic manifestations of pulmonary cryptococcosis are well documented (5–8), the descriptions of the CT findings have been limited largely to isolated case reports (9–15).To our knowledge, only one study (16) has concentrated on differences in CT appearance of pulmonary cryptococcosis between immunocompetent and immunocompromised patients, and no one between AIDS patients and other immunocompromised individuals. The purpose of this study was to retrospectively evaluate thoracic CT findings in patients with pulmonary cryptococcosis whose immune status ranged from normal to severely compromised, and determine characteristic imaging features of pulmonary cryptococcosis between patients with different immune status.

Material and Methods Patients The study included 72 patients with proven pulmonary cryptococcosis form Changzheng Hospital of the Second Military Medical University (Shanghai, China), the Public Health Clinical Center of Fudan University (Shanghai, China), and Wuhan General Hospital of CPLA Guangzhou Military Command (Wuhan, China) between January 2006 and May 2011. The study was approved by the local Institutional Review at the three institutions, and waived informed consent was obtained from each patient. They included 49 male and 23 female patients who ranged in age from 17 to 79 years (mean, 48 years  9.3). Of the 72 patients, 29 patients had no comorbidity, and 43 patients were considered immunocompromised with at least one predisposing condition, including AIDS (n ¼ 20), liver cirrhosis (secondary to hepatitis B or C, n ¼ 7; secondary to alcoholism, n ¼ 3), severe diabetes mellitus (n ¼ 5), underlying malignancy (n ¼ 3), hyperthyreosis (n ¼ 2), chronic lymphocytic leukemia (n ¼ 2), and adrenal cortical adenoma (n ¼ 1). The diagnosis of pulmonary cryptococcosis was confirmed by either cytologic observations and culture of the organism from tissue samples obtained by percutaneous biopsy (n ¼ 18), open biopsy or resection

(n ¼ 9), bronchoalveolar lavage (n ¼ 6) and transbronchial biopsy (n ¼ 2), or positive serum cryptococcal antigen test or a positive culture from pleural fluid, cerebrospinal fluid or from blood samples with clinical or radiographic evidence of active pulmonary infection (n ¼ 37). Patients in whom other pathogens were isolated from the lung were excluded from our review. The disease involved the central nervous system (CNS) in four immunocompetent patients (13.8%) and 28 immunocompromised patients (65.1%). Seven of the 29 immunocompetent patients were asymptomatic, all of whom were treated conservatively. Of the 22 symptomatic immunocompetent patients, 18 were treated with antifungal agents and the remaining four patients were treated by surgical intervention. All the immunocompromised patients (n ¼ 43) were symptomatic and treated with antifungal agents (n ¼ 38) or surgical intervention (n ¼ 5). Of the 43 immunocompromised patients, 11 (25.6%) died of cryptococcal fungemiam or underlying diseases. None of the immunocompetent patients died of pulmonary cryptococcosis.

CT scanning Chest CT scans were obtained with a variety of CT systems (Somatom Sensation 16, Siemens Medical Systems, Forchheim, Germany; Aquilion 16, Toshiba Medical Systems, Otawara, Japan; Lightspeed 64, GE Healthcare, Milwaukee, WI, is USA). Routine chest CT scans were obtained from the lung apex throughout the base. Scan increments varied from 5 to 10 mm, depending on the region to be studied. Additional high-resolution CT scans were obtained with 1-mm collimation and a high spatial frequency reconstruction algorithm at selected levels in 35 patients. All images were viewed using window settings appropriate for lung parenchyma (width, 1000–1500 H; level, –450 to –700 H) and soft tissues (width, 300–450 H; level, 30–50 H). Contrast material (Ultravist 300 mg/mL; Bayer Healthcare, Guangzhou, China) was administered in 45 patients.

CT interpretation CT scans were retrospectively reviewed on either a dedicated monitor directly interfaced with picture archiving and communication systems (PACS) (n ¼ 50) or on printed films (n ¼ 22). Three radiologists (SL, YSC, LXX – who had 30, 16, and 7 years of experience with chest CT, respectively) who had no knowledge of the patients’ underlying immune status reviewed the scans and arrived at decisions in consensus. The presence, laterality, and lobar location of nodules, masses, areas of ground-glass attenuation (GGO),

Downloaded from acr.sagepub.com at Abant Izzet Baysal University on May 18, 2014

XML Template (2014) [16.4.2014–3:11pm] //blrnas3/cenpro/ApplicationFiles/Journals/SAGE/3B2/ACRJ/Vol00000/140049/APPFile/SG-ACRJ140049.3d

(ACR)

[1–7] [PREPRINTER stage]

Xie et al.

3

areas of consolidation, reticular opacity, and linear opacity were noted. Nodules and masses were defined as rounded opacities that were at least moderately well marginated and less or greater than 3 cm in maximum diameter, respectively. Nodules/masses were further categorized according to size (diameter, 30 mm), and number (1, 2–10, and >10). If a rim of GGO or hazy increased attenuation surrounded a nodule, it was said to have a halo sign. Centrilobular nodules were defined as parenchymal opacities located in the central portion of the secondary pulmonary lobule, and tree-in-bud pattern as centrilobular branching structures that resemble a budding tree respectively. Cavitations and air bronchograms within nodules or masses and areas of consolidation were noted, respectively. Scans were also assessed for the presence or absence of pleural abnormality and lymphadenopathy. Lymph nodes were considered enlarged if their short-axis diameter was greater than 10 mm. The transaxial distribution of the abnormalities was also identified. Peripheral distribution was considered present when the abnormalities were seen mostly in the outer third of the lung; central distribution, if most abnormalities were in the inner third of the lung; peribronchial distribution, if abnormalities occurred along the bronchovascular bundles; and random distribution, if abnormalities did not fall into any of the aforementioned categories. The distribution of multiple nodules or masses was further subclassified as clustered and scattered depending on the lesions localized to a lobe or scattered to multiple lobes, respectively.

Statistical analysis Different patterns of CT scan abnormalities between immunocompromised and immunocompetent patients, AIDS and non-AIDS immunocompromised patients were compared by Fisher’s exact test. A significant difference was considered to be present for P values

Pulmonary cryptococcosis: comparison of CT findings in immunocompetent and immunocompromised patients.

Computed tomography (CT) findings in patients with pulmonary cryptococcosis have been reported, however, many reports were limited by the small number...
293KB Sizes 0 Downloads 3 Views