Table 1

Clinical findings in adaptor protein complex-4 (AP-4) deficiency syndrome patients

Patient	Present study		Verkerk et al 200911
Patient	IV-4	IV-5	IV-1	IV-3	IV-4	IV-5^*	IV-6
AP-4 subunit disrupted	AP4E1	AP4E1	AP4M1	AP4M1	AP4M1	AP4M1	AP4M1
Sex	F	M	F	M	F	M	M
Age at evaluation (years)	23	22	24	23	22	1.5	21
Early infantile hypotonia	+	+	+	+	+	+	+
Spastic tetraplegia	+	+	+	+	+	NA	+
Hypertonia	+	+	+	+	+	NA	+
Hyperreflexia	+	+	+	+	+	NA	+
Babinski sign	+	+	+	+	+	NA	+
Head circumference	-3 SD	-3 SD	-1 SD	0 SD	-2 SD	NA	-2.5 SD
Severe ID	+	+	+	+	+	+	+
Epilepsy	+	+	−	−	−	−	−
Ambulation	−	−	−	−	−	NA	−
Normal speech	−	−	−	−	−	NA	−
Sphincter control	−	−	−	−	−	NA	−
Stereotypic laughter	+	+	+	+	+	NA	+
Drooling	+	+	+	+	+	NA	+
Eye evaluation	Normal	Normal	NA	Normal	NA	NA	Pale optic discs
Hearing evaluation	Normal	Normal	NA	NA	NA	NA	NA
Neuroimaging	MRI: dilated ventricles, cerebellar atrophy, abnormal white matter	CT: dilated ventricles, prominent cisterns	CT: normal (age 3 months)	MRI: dilated ventricles, cerebellar atrophy, abnormal white matter	MRI: dilated ventricles, abnormal white matter	NA	MRI: dilated ventricles, cerebellar atrophy, abnormal white matter

↵* Patient died at 17 months of age from aspiration pneumonia.
F, female; ID, intellectual disability; M, male; NA, not available; +, present; −, absent.