Pulmonary cryptococcus infection

Pulmonary

cryptococcosis complicated with pulmonary aspergillosis: a series of studies and a literature review. Histopathological findings and CT results of the patient. A: From P2, found in a single tissue sample with cryptococcus and Aspergillus infection. The lung tissue sent for examination showed foci of coagulative necrosis, in which refractory strong spores were seen, and neutrophilic exudates, abscess formation, in which sharply branched hyphae and spores were also seen, and eosinophils and lymphocyte infiltration in the adjacent lung tissue. The histologic changes were those of pulmonary cryptococcosis combined with Aspergillus infection. B: The patient’s CT results are arranged in chronological order. The patient’s CT results are arranged in chronological order. The sequence is as follows: initial diagnosis of pulmonary cryptococcosis, diagnosis of pulmonary cryptococcosis combined with pulmonary aspergillosis infection, and postcure imaging

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Cryptococcosis

with pulmonary cavitation in an immunocompetent child: a case report and literature review. Images. a CT on admission showed a lesion and cavities in the right lower lobe of the lung, suggesting infection. b CT on the recovery phase (after taking fluconazole orally for 1 month) showed the lesion in the lower lobe of the right lung had reduced. c CT on the recovery phase (after taking fluconazole orally for 4 month) showed the inflammation in the lower lobe of the right lung had well absorbed

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Establishment

and evaluation of a CT-based radiomic model for AIDS-associated pulmonary cryptococcosis. A 25-year-old male with AIDS complicated by Cryptococcus pneumonia presented to the hospital with fever for 2 weeks. A CT scan showed a thin-walled cavity in the lower lobe of the left lung. The automatic machine delineated the lesion approximately 1–2 mm from its outer edge

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Establishment

and evaluation of a CT-based radiomic model for AIDS-associated pulmonary cryptococcosis. A 42-year-old man with AIDS and invasive aspergillosis presented with a 3-week history of expectoration. CT showed a thin-walled cavity lesion in the lower lobe of the left lung. The ground-glass opacity component was observed in the right outer edge of the lesion, and the radiologist manually adjusted the lesion edge after automatic machine delineation to include the GGO

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Radiopaedia • CC-by-nc-sa 3.0 • de

Pulmonary cryptococcosis is a form of pulmonary fungal infection caused by Cryptococcus gattii and C. neoformans. The respiratory tract is the principal route of entry for infection via inhalation of fungal spores.

For a general discussion of infection with this organism, please refer to the article cryptococcosis.

Epidemiology

Cryptococcosis predominantly occurs in immunocompromised patients but can also be seen in immunocompetent hosts, particularly, those exposed to avian (e.g. pigeon) droppings. The spectrum of pulmonary cryptococcosis depends on the host's defenses.

Clinical presentation

The presentation of pulmonary cryptococcosis can range from asymptomatic nodular disease to severe acute respiratory distress syndrome (ARDS) :

most often, causes several lung nodules or masses +/- cavitation, chiefly in immunocompromised patients
additionally, consolidation, mediastinal lymphadenopathy, and pleural effusion may also be present.

In the immunocompetent host the pulmonary infections normally are asymptomatic, in contradistinction to the immunocompromised patient, in whom cryptococcal infection is most often symptomatic, and commonly disseminates to the central nervous system, skin, and bones .

Overall, approximately one-third of patients are asymptomatic.

Symptoms range from a mild cough and low-grade fever to acute presentation with high fever and severe shortness of breath.

Pathology

The method of entry is usually by inhalation of cryptococcal particles into the lungs, causing pulmonary infection. Spores are found worldwide in soil contaminated by avian droppings.

Serology

Serum cryptococcal antigen (sCRAG) levels are helpful in diagnosis and follow-up.

Radiographic features

CT

In general, there are several CT patterns that can be seen:

clustered nodular pattern: most prevalent
solitary pulmonary nodule or mass with or without cavitation
scattered nodules
peribronchovascular consolidation

The most common CT findings in immunocompetent patients with pulmonary cryptococcosis are pulmonary nodules. The nodules are most often multiple, smaller than 10 mm in diameter, and well-defined with smooth margins. The nodules usually involve less than 10% of the parenchyma and tend to be distributed peripherally (up to 65% ) in the middle and upper zones. Where there are multiple nodules, they are usually bilateral . Associated cavitation may be seen in up to 40% of cases . Occasionally, unusual presentation such as large cavities may be seen .

Cavitations within nodules/masses tends to be more frequently present in immunocompromised patients than in immunocompetent patients .