Identical twins with lethal congenital pulmonary airway malformation type 0 (acinar dysplasia): further evidence of familial tendency.

We report a case of identical twins with lethal congenital pulmonary airway malformation (CPAM) type 0. Twin A expired several hours after birth, and twin B was sustained by extra-corporeal membrane oxygenation (ECMO) support; however, care was withdrawn from twin B following the autopsy of twin A, which revealed a diagnosis of CPAM type 0. Both twins showed pulmonary hypoplasia, histologically consistent with CPAM type 0 and pulmonary hypertension. Furthermore, the family also had a previous male who presented with pulmonary hypoplasia and respiratory failure and died shortly after birth; however, no autopsy was performed to confirm a diagnosis of CPAM. Here, in discussing our case, as well as previously reported cases, we demonstrate CPAM type 0's high prevalence among females (9:1 ratio). From the reported cases, it appears that CPAM type 0's tendency to recur in families is up to 40%, suggesting an autosomal recessive inheritance pattern. However, the actual tendency of familial recurrence is hard to assess due to the rarity of the disease and the potential lack of reporting CPAM type 0 cases. To our knowledge, our report represents the first description of CPAM type 0 in identical twins.