An immunocompromised patient presents with fever, hemoptysis, and pleuritic chest pain. A chest X-ray shows ground-glass opacities and serum galactomannan is positive. What is the most likely diagnosis?

The clinical presentation and test results provided strongly support the diagnosis of invasive pulmonary aspergillosis. In immunocompromised patients, particularly those with conditions such as hematological malignancies, severe neutropenia, or those undergoing immunosuppressive therapy, invasive aspergillosis is a significant concern.

The combination of fever, hemoptysis, pleuritic chest pain, and the presence of ground-glass opacities on chest X-ray aligns with the typical manifestations of this condition. Ground-glass opacities can represent infectious infiltrates or inflammation in the lungs, and this finding is often associated with various types of pneumonia, including those from fungal infections.

The positive serum galactomannan antigen test is particularly notable for diagnosing invasive aspergillosis. Galactomannan is a polysaccharide component of the Aspergillus cell wall, and its presence in the serum indicates an active infection with this pathogen. A threshold level of galactomannan can assist in confirming the diagnosis when clinical suspicion is high.

Given these factors—an immunocompromised state, characteristic symptoms, imaging findings, and a positive serum galactomannan test—the diagnosis of invasive pulmonary aspergillosis is the most plausible. Other options listed