Congenital pulmonary airway malformation in a cat.

Congenital structural anomalies of the lower airways of the respiratory tract are uncommon in cats. We describe here a case of cystic pulmonary lesions in a 6-wk-old domestic shorthair cat consistent with congenital pulmonary airway malformation (CPAM; formerly referred to as cystic adenomatoid malformation of the lung, or congenital pulmonary adenomatoid malformation; Stocker type II). CPAM is rarely reported in veterinary species and, to our knowledge, has not been reported in cats. In humans and veterinary species, individuals with CPAM (Stocker types I-IV) can be asymptomatic at birth but are predisposed to developing respiratory abnormalities that typically manifest clinically in the early years of life. We review the pathologic features of CPAM.