Familial idiopathic oedema in prepubertal children: a new syndrome

Idiopathic oedema has not been previously described in prepubertal children. Between 1977 and 1991, eighteen children (15 girls, three boys) from 13 unrelated kindreds presented with the clinical features of idiopathic oedema commencing between the neonatal period and 12 years. These comprised a triad of swelling, affective disturbance and functional autonomic symptoms. There was a family history of idiopathic oedema in 16 (89%) children, including all 15 girls, and of diabetes mellitus in 12 (67%) children, suggesting a major genetic basis for the syndrome. Laboratory investigations excluded cardiovascular, hypoproteinaemic, allergic and obstructive causes of oedema. Adherence to a restricted carbohydrate diet, the avoidance of refined carbohydrate and the correction of precipitating weight gain controlled symptoms in most children. Relapses followed dietary non-compliance and life-event stress. A neuro-transmitter-based autonomic abnormality of vascular and visceral smooth muscle tone modulated by metabolic and neuroendocrine mechanisms provides a partial explanation for this syndrome. Insulin-mediated modulation of capillary permeability to water and electrolytes may also be involved. The pathogenesis, clinical features and management of paediatric idiopathic oedema may provide a model for the adult syndrome.