Abstract
Adults with intellectual and developmental disabilities (IDD) are increasingly living into adulthood, highlighting the need for adult clinicians to expand their familiarity with congenital conditions. Smith-Lemli-Opitz syndrome (SLOS) is a rare autosomal recessive inborn error of cholesterol synthesis. SLOS is commonly diagnosed in childhood, but a number of adults with IDD progress into adulthood without a formal diagnosis. We present an 18-year-old male with a history of IDD and altered pain sensation who was hospitalized following a self-inflicted knife injury resulting in a traumatic ventricular septal defect. Over the following 15 years, the patient continued to exhibit self-injurious behaviors. At the age of 33, caregivers consented to further work-up of his intellectual disability, and whole-exome genetic sequencing revealed a diagnosis of SLOS. The clinical course of this patient represents a unique presentation of altered pain sensation, a delayed diagnosis of SLOS into adulthood, and the challenges of providing care to an adult with IDD. The case further highlights the importance of understanding the typical workup and management of genetic and congenital conditions arising in childhood.