MPO and pulmonary alveolar proteinosis: The diagnostic power of NE, MPO, and cir‐nDNA as determined by the Area Under Receiver Operating Curves (AUROC) was 0.95, 097, and 0.64; 0.99, 1.0, and 0.82; and 0.94, 1.0, and 0.93, in NS, S, and PAP patient subgroups, respectively.