See Hemoptysis
Massive: intubate (ideally ETT >8.0), angio or bronch to identify and stop localized source, consider nebulized TXA
Correct coagulopathy
Methylprednisolone 1g + plasmapheresis
See Glomerulonephritis, consult nephrology
Plasmapheresis shown to be beneficial 
In severe cases may need:
Rheumatology eval: Immunosuppressants
Massive: intubate (ideally ETT >8.0), angio or bronch to identify and stop localized source, consider nebulized TXA
Correct coagulopathy
Methylprednisolone 1g + plasmapheresis
Rheumatology eval: Immunosuppressants
Goodpasture syndrome
Infectious
Nephrogenic systemic fibrosis
Bronchitis
Drug rash with eosinophilia and systemic symptoms syndrome
Pneumonia
Eosinophilic granulomatosis with polyangiitis
Lung abscess