대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Semi-invasive Aspergillosis

Radiologic Findings

Thin-section CT scan shows a cavitary nodule with surrounding halo of ground-glass attenuation in left upper lobe. Underlying centrilobular emphysema is noted in both lungs.

It is not clear whether the lesion happened to be located around a preexisting emphysematous bulla or the cavity represents central necrosis.

Brief Review

This type is the chronic granulomatous form of aspergillosis, arising in the setting of mild immunologic compromise and being a progressive form of localized disease. This unusual form of pulmonary aspergillosis resembles clinically a number of other chronic pulmonary diseases including tuberculosis, actinomycosis, histoplasmosis (1).

The patients are usually middle-aged and have poor nutrition due to alcoholism, diabetes mellitus, chronic granulomatous disease or connective tissue disorders. Pulmonary abnormalities resulting in lowered defense mechanisms of the lung such as fibrotic area of mycobacterial infection, chronic obstructive lung disease, previous surgery, radiation therapy, pulmonary infarction or pneumoconiosis may be associated (2).

Clinical symptoms include cough, sputum, fever, weight loss, and hemoptysis, usually persisting at least for a few months. This time course is different from that of invasive aspergillosis (IPA) in which the rate of progression depends on the degree of immunosuppression of host (usually two or three weeks).

Gefter et al (3) reviewed radiographic findings of semi-invasive pulmonary aspergillosis in five patients. They appeared as consolidation or progressing cystic infiltrate subsequently forming a thick-walled cavity and aspergilloma with upper lobe predominance. And pleural thickening was frequently seen.

According to Kim et al (4) in a review of six cases of semi-invasive aspergillosis, the CT findings of the disease were diverse ranging from findings of bronchopneumonia to cavitary consolidation containing an aspergilloma. Main feature distinguishing chronic necrotizing pulmonary aspergillosis from aspergilloma is the presence of obvious tissue invasion and destruction in the former. Whereas, pulmonary aspergilloma usually forms within preexisting cavity without tissue invasion. Pathologically, the findings of angioinvasion are lacking which are characteristic in IPA.

Treatment option depends on the clinical status of the patients; from observation in asymptomatic patients to antifungal therapy or surgical resection in patients with hemoptysis or progressing disease.

References

1. Cheon J-E, Im J-G, Kim MY, Lee JS, Choi GM, Yeon KM. Thoracic actinomycosis: CT findings. Radiology 1998; 209:229-233

2. Binder RE, Faling LJ, Pugatch RD, Mahasaen C, Snider GL. Chronic necrotizing pulmonary aspergillosis: a discrete clinical entity. Medicine 1982; 61:109-124

3. Gefter WB, Weingrad TR, Epstein DM, Ochs RH, Miller WT. "Semiinvasive" pulmonary aspergillosis: A new look at the spectrum of Aspergillus infections of the lung. Radiology 1981; 140:313-321

4. Kim SY, Lee KS, Han J, et al. Semi-invasive pulmonary aspergillosis: CT and pathologic findings in six patients. (Submitted to Radiology)

Keywords

Lung, Infection, Fungal infection, Semi-invasive Aspergillosis