Pediatric Aspergillosis

  • Etiology: Aspergillus infection whose manifestation is dependent on patient’s immune status
  • Allergic Bronchopulmonary Aspergillosis (ABPA)
    — Etiology: hyperimmune status – hypersensitivity reaction associated with asthma
    — Imaging: affects airways, mucoid impaction with central bronchiectasis – “gloved finger”
    — Clinical: uncommon in children
  • Aspergilloma (Fungus ball / mycetoma)
    — Etiology: normal immunity
    — Imaging: affects / infects pre-existing cavity
    — Complications: pulmonary hemorrhage
  • Invasive aspergillosis
    — Etiology: hypoimmune status / immunocompromised – post chemotherapy or stem cell transplant
    — Imaging: affects parenchyma – bronchocentric / angiocentric lesion, halo sign – parenchymal density surrounded by irregular ground glass density (hemorrhagic halo), air crescent sign – central necrosis detached from wall
    — Complications: 25-50% has systemic hematogenous dissemination to brain, liver, spleen, kidneys
    — DDX: other fungi – Candidiasis, Cryptococcus

Radiology Cases of Aspergillosis

Radiology Cases of Allergic Bronchopulmonary Aspergillosis (ABPA)

Radiology Cases of Aspergilloma

Radiology Cases of Invasive Aspergillosis

CXR and CT of invasive aspergillosis
CXR AP and lateral (above) shows a round opacity on the lateral view posteriorly projecting over a mid-thoracic vertebral body. Axial CT without contrast of the chest shows a cavitary lesion in the superior segment of the right lower lobe that has a halo sign peripherally with the parenchymal density surrounded by an irregular ground glass density and an air crescent sign with an area of central necrosis detached from the wall of the lesion.
CT of invasive aspergillosis
CXR AP (above) shows a triangular appearing lesion in the right middle lobe. Axial CT with contrast of the lung (below) shows a thick walled cavitary lesion in the right lower lobe that contains debris.
CXR and CT of invasive aspergillosis
CXR on day 8 of the fever (above left) shows opacities in the left upper lobe and right middle lobe. Axial CT without contrast of the chest on day 13 of the fever (above right) shows parenchymal opacities surrounded by irregular ground glass density (halo sign). CXR on day 20 of the fever (below left) shows interval cavitation of the bilateral lung lesions which on axial CT with contrast of the chest on day 34 of the fever (below right) shows central necrosis in the lesions which is detached from the wall (air crescent sign).