Reflex sympathetic dystrophy: complex regional pain syndrome type I in children with mitochondrial disease and maternal inheritance.
OBJECTIVE
Complex regional pain syndrome type I (CRPS-I), previously known as reflex sympathetic dystrophy (RSD), is an idiopathic condition characterised by localised, abnormally intense and prolonged pain, allodynia and autonomic nervous system changes (ie, swelling, skin colour and temperature changes and altered perspiration) that usually appear following a "noxious" trigger such as trauma or surgery. The objective of this report is to demonstrate that children with CRPS-I can have additional dysautonomic conditions secondary to an underlying maternally inherited mitochondrial disease, an association not previously published.


METHODS
Medical records of about 500 patients seen by one paediatric metabolic geneticist were reviewed to identify children meeting established CRPS diagnostic criteria.


RESULTS
CRPS-I was present in eight children in seven families, each of which also had additional functional/dysautonomic conditions, the most common (> or = 4 cases per condition) being gastrointestinal dysmotility, migraine, cyclic vomiting and chronic fatigue. All seven probands studied met Nijmegen (2002) diagnostic criteria for definite mitochondrial disease on the basis of the clinical signs and symptoms and biochemical analyses. Six of the seven families met our pedigree-based criteria for probable maternal inheritance.


CONCLUSIONS
In one tertiary-care paediatric genetics practice, children meeting the CRPS-I diagnostic criteria frequently had additional autonomic-related conditions secondary to maternally inherited mitochondrial disease, suggesting that mitochondrial DNA sequence variants can predispose children towards the development of CRPS-I and other dysautonomias. CRPS-I should be considered in patients with mitochondrial disease who complain of idiopathic pain. Maternally inherited mitochondrial disease may not be a rare cause of CRPS-I, especially in children who present with other manifestations of dysautonomia.
Higashimoto
T
T
Division of Medical Genetics and the Saban Research Institute, Childrens Hospital Los Angeles, Los Angeles, California, USA.
Baldwin
E E
EE
Gold
J I
JI
Boles
R G
RG
D000293:Adolescent; D001342:Autonomic Nervous System Diseases / Q000209:etiology* / Q000235:genetics; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004272:DNA, Mitochondrial / Q000235:genetics; D005111:Extrachromosomal Inheritance / Q000235:genetics; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D028361:Mitochondrial Diseases / Q000150:complications* / Q000235:genetics; D012019:Reflex Sympathetic Dystrophy / Q000209:etiology / Q000235:genetics; D012189:Retrospective Studies
D004272:DNA, Mitochondrial