대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Pulmonary Cryptococcosis

Radiologic Findings

Chest radiograph shows confluent small nodular opacities on left upper lobe. CT shows confluent small nodules on left upper lobe peripheral portion. Faint ground glass opacities are suggested surrounding the nodules. No calcification, cavity or mediastinal lymph nodes are enlarged (not-shown).

Open lung biopsy of the nodular lesion shows multiple pulmonary nodules with chronic granulomatous inflammation with central necrosis and surrounding granulomas with multinucleated giant cells. Specific stain with GMS shows black stained Cryptococcus.

Brief Review

Cryptococcosis neoformans is a ubiquitous fungus found worldwide, particularly in soil contaminated by pigeon droppings. It is a thin-walled nonmycelial budding yeast that is characterized by a thick polysaccharide capsule best seen on India ink preparations. Cryptococcal infection usually results from inhalation of organisms. The spectrum of pulmonary cryptococcosis depends on host defences. In the immunocompetent, cryptococcal infections are commonly localized in the lung and patients are asymtomatic; whereas, in the immunocompromised, cryptococcal infections often cause symptomatic pulmonary infections and often disseminate to the central nervous system, skin, and bones.
Radiographically, the described pulmonary findings of cryptococcosis are diverse but most commonly include single or multiple nodular nodules and segmental or lobar consolidation. Additional features include interstitial infiltrates, miliary disease, cavitation, lymph node enlargement, and pleural effusions. The latter findings has been decribed more frequently in the immunocompromised, particularly those with human immunodeficieny virus (HIV) infection. The report by Friedman et al. of 14 patients known to be HIV-1 antibody positive with chest radiographic findings showed interstitial infiltrates and focal or widespread alveolar consolidation to be the most common findings. The six patients showed ground glass opacities. Therefore, earlier reports suggested that there was difference in the radiographic abnormalities between immunocompromised and immunocompetent individuals with pulmonary cryptococcosis. But recent reports show there is no difference in radiologic findings between of immunocompromised and of immunocompetent. Zinck and colleagues reviewed the CT and pathologic findings in 7 immunocompromised and 4 immunocompetent patients. In their study, nodules, either solitary or multiple, and often seen in association with the CT halo sign and other parenchymal masses and consolidation, are the most common CT manifestation of pulmonary cryptococcosis. A more recent report of pulmonary cryptococcosis in 46 patients by Lacomis et al. showed there was no difference in the radigraphic appearance of pulmonary disease between HIV-infected patients and other immunocompromised individuals. Bilateral pulmonary abnormalities and airspace consolidation were the most common radiologic manifestations of pulmonary cryptococcosis in the three groups of patients (solid organ transplant, AIDS, and non organ transplant and non AIDS). Nodules/masses were also quite common in all groups. In all groups, a combination of findings consisting of consolidation, nodules and effusions or lymph node enlargement (HIV and non-organ transplant) was more frequent than a single abnormality.
Most patients with pulmonary cryptococcosis do not need treatment. But amphotericin B, flucytosine has required in disseminated disease.

References

1. Khoury MB, Godwin JD, Ravin CE, Gallis HA, Halvorsen RA, Putman CE. Thoracic cryptococcosis: immunologic competence and radiologic appearance. AJR Am J Roentgenol. Roentgenol 1984; 142:893-896.

2. Patz EF, Jr., Goodman PC. Pulmonary cryptococcosis. J Thorac Imaging 1992; 7:51-55.

3. Friedman EP, Miller RF, Severn A, Williams IG, Shaw PJ. Cryptococcal pneumonia in patients with the acquired immunodeficiency syndrome. Clin Radiol 1995; 50:756-760.

4. Lacomis JM, Costello P, Vilchez R, Kusne S. The radiology of pulmonary cryptococcosis in a tertiary medical center. J Thorac Imaging 2001; 16:139-148.

5. Zinck SE, Leung AN, Frost M, Berry GJ, Muller NL. Pulmonary cryptococcosis: CT and pathologic findings. J Comput Assist Tomogr 2002; 26:330-334.

Keywords

Lung, Infection, Fungal infection,