Aspergillus nodules; another presentation of Chronic Pulmonary Aspergillosis

Abstract

Background: There are a number of different manifestations of pulmonary aspergillosis. This study aims to review the radiology, presentation, and histological features of lung nodules caused by Aspergillus spp.

Methods: Patients were identified from a cohort attending our specialist Chronic Pulmonary Aspergillosis clinic. Patients with cavitating lung lesions, with or without fibrosis and those with aspergillomas or a diagnosis of invasive aspergillosis were excluded. Demographic, laboratory, and clinical data and radiologic findings were recorded.

Results: Thirty-three patients with pulmonary nodules and diagnostic features of aspergillosis (histology and/or laboratory findings) were identified. Eighteen (54.5 %) were male, mean age 58 years (range 27-80 years). 19 (57.6 %) were former or current smokers. The median Charleston co-morbidity index was 3 (range 0-7). All complained of a least one of; dyspnoea, cough, haemoptysis, or weight loss. None reported fever. Ten patients (31 %) did not have an elevated Aspergillus IgG, and only 4 patients had elevated Aspergillus precipitins. Twelve patients (36 %) had a single nodule, six patients (18 %) had between 2 and 5 nodules, 2 (6 %) between 6 and 10 nodules and 13 (39 %) had more than 10 nodules. The mean size of the nodules was 21 mm, with a maximum size ranging between 5-50 mm. No nodules had cavitation radiographically. The upper lobes were most commonly involved. Histology was available for 18 patients and showed evidence of granulation tissue, fibrosis, and visualisation of fungal hyphae.

Conclusion: Pulmonary nodules are a less common manifestation of aspergillosis in immunocompetent patients. Distinguishing these nodules from other lung pathology may be difficult on CT findings alone.

Keywords: Aspergillus; Chronic pulmonary aspergillosis; Fungal infection of lung; Pulmonary nodule.

Fig. 1

Different patterns of Aspergillus nodule disease. A showing multiple nodules, B a single pulmonary nodule on background of emphysematous lungs

Fig. 2

CT imaging showing cavitating disease initially, which developed into nodular disease

Fig. 3

Biopsy demonstrating inflammation and necrosis and fungal hyphae (low power) and fungal conidia (arrow) on high power

Fig. 4

Current management algorithm for Aspergillus nodules. CXR = chest radiograph; CT = computed tomography; FU = follow up