Congenital pulmonary alveolar proteinosis

Other Names: Pulmonary alveolar proteinosis, congenital; Congenital PAP

Congenital pulmonary alveolar proteinosis is a rare form of respiratory failure that is present from birth. In this condition, a substance made up of fat and protein (surfactant) builds up in the air sacs (alveoli) of the lungs, making breathing difficult.

Epidemiology

Congenital pulmonary alveolar proteinosis is rare and occurs in about 1 in 1.5 million births.

Cause

Congenital pulmonary alveolar proteinosis is caused by genetic changes (mutations) in one of several different genes.

Inheritance

It is inherited in either an autosomal dominant, autosomal recessive or X-linked recessive pattern depending on the gene involved. If the gene involved is the ABCA3 gene, the CSF2RB gene, or the SFTPB gene, inheritance is autosomal recessive. If the gene involved is the SFTPC gene, inheritance is autosomal dominant. If the gene involved is the CSF2RA gene, inheritance is X-linked recessive.

Signs and symptoms

Symptoms typically begin the newborn period and get worse over time.

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. 30%-79% of people have these symptoms

• Crazy paving pattern on pulmonary HRCT
• Failure to thrive in infancy(Faltering weight in infancy)
• Hypoxemia(Low blood oxygen level)
• Respiratory distress(Breathing difficulties)
• Respiratory failure requiring assisted ventilation
• Restrictive ventilatory defect(Stiff lung or chest wall causing decreased lung volume)

5%-29% of people have these symptoms

• Acute infectious pneumonia
• Autoimmune antibody positivity
• Cough(Coughing)
• Crackles
• Elevated carcinoembryonic antigen level
• Foam cells
• Tachycardia(Fast heart rate)
• Tachypnea(Increased respiratory rate or depth of breathing)

Diagnosis

Congenital pulmonary alveolar proteinosis is diagnosed based on the symptoms, imaging studies and genetic testing.

Treatment

Treatment is difficult and can involve washing out the lungs (bronchoalveolar lavage) or lung transplant. Infants may be put on an artificial breathing machine. Without treatment, this condition may be fatal within a few months of life.

NIH genetic and rare disease info

• NIH info on Congenital pulmonary alveolar proteinosis

Congenital pulmonary alveolar proteinosis is a rare disease.