A CASE STUDY OF CHILDHOOD DISINTEGRATIVE DISORDER USING SYSTEMATIC ANALYSIS OF FAMILY HOME MOVIES

Background: Childhood Disintegrative Disorder (CDD) is a rare Pervasive Developmental Disorder. Like autism, it is characterised by impairments in social interaction and communication and by repetitive behaviours. In CDD, symptom emergence must be preceded by a period of at least two years of typical development and a loss of skills in several developmental domains (American Psychiatric Association, 2000). Objectives: The purpose of the case study is to examine the validity of CDD and investigate the timing of regression. Methods: We describe the development of a boy with CDD who after a period of 4 years of typical development experienced a loss of skills parallel to the emergence of autism symptoms. Moreover, unique to this study, family home movies recording his development from birth through the regression were systematically analyzed by coders unaware of the child’s diagnosis or the purposes of the study, trained to reliability on an objective coding system (Werner & Dawson, 2005). Using Noldus 5.0, The Observer, the rates of gaze to people, non-word vocalizations, one-word and multi-word verbalizations, orienting to name, pointing, repetitive motor movements, repetitive actions on objects, and unusual visual behaviours were objectively quantified. Results: The systematic analysis of family home movies, as well as clinical observation, show a dramatic reduction of social orienting behaviours, pointing, and language, as well as a great increase of repetitive and unusual visual behaviours after a period of 4 years of normal development. No medical causes or correlates were found. The regression was quite abrupt in its onset and losses continued for up to a year afterward. Improvement has been limited. Conclusions: CDD validity is supported. The characteristics of the regression timing and the need of clearer diagnosis criteria due to the overlap of CDD with autism with regression are also discussed.