We did not consider Smith-Magenis syndrome for the patient described in our article.1 This chromosomal microdeletion syndrome is associated with a clinically recognizable pattern of physical, developmental and behavioural features.2 The facial appearance is characterized by broad, square shape, brachycephaly, prominent forehead, synophrys, up-slanting palpebral fissures, deep-set eyes, broad nasal bridge, midfacial hypoplasia and prognathism. The behavioural phenotype includes sleep disturbance, attention deficit disorders, attention-seeking, aggression, self-injurious behaviour and stereotypes, especially the self-hug and lick-and-flip movements.
We suspect that Chitra Prasad raised the possibility of Smith-Magenis syndrome because the patient was mentally retarded and ingested foreign bodies. However, 2 important distinctions must be made. First, most people with Smith-Magenis syndrome have mild to moderate mental retardation, whereas this patient had severe to profound retardation. Second, the syndrome is associated with polyembolokoilamania, the insertion of objects into body orifices such as the rectum, vagina, urethra, nose and ear, rather than pica, in which ingestion is restricted to the oral route, as in the patient we described. Smith-Magenis syndrome is rare, occurring in 1 of 25 000 births, but pica affects some 20% of mentally retarded people.3
Other facts about this patient, not given in the article, made a diagnosis of Smith-Magenis syndrome unlikely. For example, the patient did not show the distinctive facial appearance or behavioural phenotype of this syndrome. Furthermore, virtually all cases of Smith-Magenis syndrome occur de novo, whereas the patient's family included other mentally retarded siblings, which indicated an inherited abnormality.
Fawzi E. Ali Medical Rehabilitation Center UN Square Al-Sabah Health Zone Kuwait