Case Report
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Apr 16, 2021; 9(11): 2619-2626
Published online Apr 16, 2021. doi: 10.12998/wjcc.v9.i11.2619
Cryptococcus infection with asymptomatic diffuse pulmonary disease in an immunocompetent patient: A case report
Yong Li, Lei Fang, Fang-Qun Chang, Fang-Zhou Xu, Yan-Bei Zhang
Yong Li, Lei Fang, Fang-Qun Chang, Fang-Zhou Xu, Yan-Bei Zhang, Department of Geriatric Respiratory and Critical Care, The First Affiliated Hospital of Anhui Medical University, Hefei 230000, Anhui Province, China
Yong Li, Department of Tuberculosis, Anhui Medical University Clinical College of Chest & Anhui Chest Hospital, Hefei 230000, Anhui Province, China
Author contributions: Li Y, Chang FQ, and Xu FZ collected the clinical data and wrote the paper; Zhang YB and Fang L contributed to the design and revision of the paper.
Supported by The Colleges and Universities in Anhui Province Natural Science Research Projects, No. KJ2018A0208.
Informed consent statement: Informed written consent was obtained from the patient for publication of this report and any accompanying images.
Conflict-of-interest statement: The authors declare that they have no conflicts of interest to report.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Yan-Bei Zhang, MAMS, Chief Doctor, Professor, Department of Geriatric Respiratory and Critical Care, The First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Street, Hefei 230000, Anhui Province, China. zhangyanbei1963@126.com
Received: December 7, 2020
Peer-review started: December 7, 2020
First decision: December 21, 2020
Revised: January 9, 2021
Accepted: February 10, 2021
Article in press: February 10, 2021
Published online: April 16, 2021
Processing time: 115 Days and 22.1 Hours
Abstract
BACKGROUND

Cryptococcus presenting as an opportunistic pathogen mainly affects immunocompromised patients, but the disseminated form of infection is rare among immunocompetent populations. The partial radiographic characteristics of pulmonary cryptococcosis mimic lung carcinoma, leading to unnecessary open chest exploratory surgery, and the lack of a gold-standard noninvasive diagnostic increases the risk of misdiagnosis. Positron emission tomography/computed tomography (PET/CT), a sensitive method for distinguishing malignant tumors, coupled with cryptococcal latex agglutination test showing a high positive rate may overcome these issues.

CASE

A 36-year-old man presented for general examination, without health complaints. Routine CT showed multiple pulmonary nodules and a mass with high maximum standardized uptake value. Initially, we suspected primary malignancy with hematogenous metastasis. Although his routine fungal analysis had been negative, subsequent CT-guided percutaneous core needle biopsy and histopathology examination indicated a diagnosis of pulmonary cryptococcosis. Fluconazole (200 mg/d) antifungal drug treatment was initiated, and 1 mo later the pulmonary mass had reduced in size markedly (on chest CT scan) without any complications.

CONCLUSION

Serologic and PET/CT examinations may not rule out cryptococcosis, and percutaneous lung puncture is critical under all circumstances.

Keywords: Cryptococcus; Immunocompetent; Positron emission tomography; Computed tomography; Cryptococcal latex agglutination test; Lung diseases; Fungal; Case report

Core Tip: Cryptococcosis is a systemic fungal infection, with presentation ranging from asymptomatic pulmonary involvement to meningitis and disseminated disease. Generally, cryptococcosis is considered an opportunistic infection in immunocompro-mised individuals, affecting persons with human immunodeficiency virus infection in particular. Mass-like and disseminated cryptococcosis lesions are rare in patients with normal immunity, and a negative result on the cryptococcal latex agglutination test may be related to low-grade virulence of the fungus. We describe here a case of pulmonary cryptococcosis that was likely caused by a low-virulence strain, presenting bilaterally distributed lesions on imaging and mimicking hematogenous metastasis.