From the question on page 12.

Our initial diagnostic hypothesis was pulmonary alveolar phospholipoproteinosis in view of the “crazy paving” appearance on the CT scan. Bronchoalveolar lavage was performed and the fluid recovered had a total cell count of 700×10³/ml (89% macrophages, 3% neutrophils, 1% eosinophils). There were no germs, tumour cells or alveolar bleeding. The periodic acid/Schiff test was negative. Polarised light microscopy revealed …