CASK Mutation in an Infant with Microcephaly, Pontocerebellar Hypoplasia, and Hearing Loss

The requirement for informed consent was waived by board. A female infant was born at 40 weeks of gesta-tion by vaginal delivery at a local hospital. There were no remarkable complications during the pregnancy. The infant had a birth weight of 3,200 g (50th percentile), a height of 49.5 cm (50th to 75th percentile), and a head circumference of 33.5 cm (25th to 50th percentile). Immediately after birth, the auditory brainstem response test results were 35 dB on the left and 60 dB on the right and she had hearing aid treatment. She was found to have severe microcephaly (<1st percen-tile) persistently in routine infant check-ups (at 2 months), so she underwent brain computed to-mography (CT) when she was 5 months old at another clinic. Cerebellar hypoplasia was found on the brain CT. When she came to our clinic (at 6 months), her weight was 7,830 g (50th to 75th percentile), her length was 65.3 cm (25th to 50th percentile), and her head circumference was 37.7 cm (–4 SD [38.1 cm]). She had facial particularities, including an oval face, micrognathia, arched eyebrows, hypertelorism, long eyelashes, epican-thus, low-set and prominent ears, long philtrum,