Hypoplasia of the parabrachial/kölliker-fuse complex in perinatal death.

We report the first observation of perinatal death attributable to morphological alterations of the parabrachial/Kölliker-Fuse complex. In an infant, born at 41 weeks of gestation with severe signs of asphyxia and dead 20 h after delivery, we observed the presence of rare and immature neurons in the brain stem areas of both lateral and medial parabrachial nuclei and the absence of the characteristic neurons of the Kölliker-Fuse nucleus. Such hypoplasia was associated with severe hypoplasia of the arcuate nucleus and pulmonary hypoplasia.