Holly's Story: Illustration of an Attention Deficit Hyperactivity Disorder Case

Abstract

During the last 10years a significant increase of childhood neuropsychiatric disorders, such as attention deficit hyperactivity disorder (ADHD), has been reported. ADHD is believed to have a multifactorial etiology including multiple genetic and prenatal environmental factors. For this reason, there has been a recent revival regarding the role of autoimmunity in this pathology. An ADHD combined-type patient born from a drug-addicted mother was studied. Neuropsychological tests according to the criteria of the 4 th edition of the Diagnostic and Statistical Manual (DSM4) permitted us to make the ADHD-diagnosis. The HLA-A, -B, and -DRBI alleles of the child were determined by sequence-based typing (SBT) after DNA extraction. Although no autistic behavioral features were observed in the patient, a double genetic association between ADHD and autism was reported. In fact, HLA class I alleles (A*02 and B*44) associated to autism and the HLA class II allele (DRBI*04) associated both to autism and ADHD were identified.Attention deficit hyperactivity disorder (ADHD) is a neurobehavioral disorder that arouses continuous and increasing interest from the clinicians and genetists oriented to individuate further details which will be able to help the affected children and their families. ADHD is a multifactorial illness often linked to other childhood disorders, and multiple genes of the immune system seem to be involved in its aetiopathogenesis (I). It is also very important to report the existence of non-genetic factors, such as a premature birth, maternal smoking during pregnancy, and prenatal drug exposure that may increase the risk for behavioral disorders (2). In this study, we investigate the genetic factors that could constitute the physiological bases of this neurobehavioral disorder. In particular, the HLA genes have been studied as a group of highly polymorphic genes, mainly responsible for autoimmune etiology of a large group of pathologies. MATERIALS AND METHODSHolly is the fictitious name of a nine-year old boy with an ADHD diagnosis who arrived at our institute with other pediatric patients who were admitted to a case-control study with the aim of finding a possible association between HLA region and childhood neuropsychiatric disorders. Holly is different from the other patients as he has a complex story and he presents a multiplicity of risk factors. Firstly, Holly's mother took drugs (heroin) during pregnancy. This fact elicited withdrawal symptoms