Congenital Pulmonary Airway Malformation

Question 1

What is CPAM?

Incidence of CPAM?

Answer 1

Congenital pulmonary malformation

• rare anomaly of the respiratory tract
• development malformation of the lower respiratory tract

1/8,300-35,000 live births
1/3 diagnosed after birth

Question 2

Is CPAM related to race, age or exposure?

Answer 2

NO

Question 3

How are CPAMS distributed?

Answer 3

Equally distributed between right and left lobes

Typically found in lower lobes

Not typically found bilaterally

Question 4

What are the type of CPAMs?

[Type 0, 1, 2, 3, and 4]

Answer 4

Type 0- rarest; 1-3%; originates from tracheal or bronchial tissue; small cysts <0.5 cm; no gas exchange; death at birth

Type 1-most common form 60-70%; distal bronchi; originated 7-10 weeks GA; thin walled cysts 2-10 cm; adjacent alveoli are normal; at risk for developing malignancy

Type 2-15-20% of CPAMs; multiple cysts 0.5-2 cm; anomalies associated include tracheoesophageal fistual, bilateral renal agenesis;

Type 3-5-10%; large and involves one or more lobes, mixture of cystic and solid; not associated with malignancy; birth severe respiratory distress or death

Type 4-(5-10%); max diameter of 7 cm; cause tension ptx or infection; strongly associated with malignancy

Question 5

Prenatal presentation? What is the natural course of CPAM?

Answer 5

Appearance on second trimester ultrasound.

Typically peak CPAM size at 25 weeks

Regress and resolve during course of gestation approximately 50% of the time

Question 6

Appearance of CPAM on prenatal imaging

Answer 6

Microcystic lesions-<5mm diameter cystic appearance echogenic and solid

Macrocystic lesions: >5 mm in diamter

Question 7

Differential diagnosis for chest masses

Answer 7

1) CPAM
2) Bronchopulmonary sequestration
3) Congenital lobar inflation
4) Bronchogenic cyst
5) Diaphragmatic hernia
6) Congenital high airway obstruction
7) Neuroenteric cyst
8) Mediastinal cystic teratoma
9) Fetal neoplasm

Question 8

Neonatal period for infants with CPAM

Answer 8

3/4 of patients with CPAM are asymptomatic

1/4 of patients are symptomatic

Type 0-no gas exchange, affected infants die

Type 1- tachypnea, increased RR, cyanosis

Type 2-similar to type 1

Type 3- fetal hydrops and pulmonary hypoplasia are typically

Type 4- infant presenting with tension ptx