Abstract
Background: Pulmonary alveolar proteinosis (PAP) is an uncommon illness characterized by the aberrant accumulation of surfactant lipids and proteins in the lungs. Both autoimmune and secondary PAP have been linked to autoimmune illnesses, such as rheumatoid arthritis (RA).
Case Presentation: A 29-year-old female living in Saudi Arabia was presented to the emergency department with worsening dyspnea for 6 months. A systemic evaluation revealed a considerable history of polyarthritis and early morning stiffness over 4 years. A high-resolution CT scan of the chest was performed, which revealed a diffuse bilateral appearance of a crazy paving pattern. The bronchoalveolar lavage fluid included proteinaceous granular debris that tested positive for Periodic Acid-Schiff. Following the whole lung lavage (WLL), the patient’s health improved dramatically, with oxygen saturation ranging from 90%-93%. According to findings, this patient had PAP together with a newly established seropositive RA. Her quality of life improved with WLL and the start of a brief, low-dose prednisone treatment with hydroxychloroquine.
Conclusion: PAP is rarely related to connective tissue disorders such as RA. It is an important differential diagnosis for interstitial lung disease-RA. The pathophysiology of these relationships is currently poorly understood.

Key words: Pulmonary alveolar proteinosis, rheumatoid arthritis, Anti-GM-CSF antibody, molgramostim, case report