Background Fabry disease is known as a lysosomal storage disease, which had been recognized as a rare inherited disease . Alpha galactosidase A (α-gal A) gene is coded on X chromosome, so it has been considered to be developed predominantly in male, however, recent studies revealed not a few female patients exist even though the symptom is rather mild compared to that of classical male patients . Fabry disease develops various symptoms, such as, cerebral infarction, cardiomegaly, and kidney failure, corneal opacity, angiokeratoma, hearing loss, chronic peripheral pain, and so on. Especially, peripheral pain is usually antecedent to the major symptoms, such as kidney failure, cerebral infarction and heart failure. Classical Fabry patients present peripheral pain in their childhood, and sometimes this symptom is overlooked. In female, the symptom is rather mild and appears later than classical type, so that it can be possible this symptom occur in the adulthood.
Objectives In this study, to clarify whether Fabry disease is hidden in fibromyalgia patients, α-gal A activity were measured and compared with health control. Moreover, α-gal A activity was statistically examined with patients' medical information.
Methods 54 patients with fibromyalgia (female:male =48:6, average age: 42.0±13.4 year old) and age and sex matched 105 healthy controls (female:male =92:13, average age: 40.1±15.1 year old) were selected (p=0.512). Blood sample was obtained from each subject and measured α-gal A activity by dried blood spot method (Chamoles NA, et al, 2004). Precise medical histories including family history within the relation in the second degree were obtained from fibromyalgia patients. Statistical analysis were done by student t-test, Man-Whitney U-test and Spearman test.
Results Mean value of α-gal A activity of fibromyalgia patients was 26.2 + 9.2 AgalIU, whereas that of healthy control was 29.2±9.2 AgalIU (p=0.074, by t-test). There was no significant correlation between α-gal A activity and present age, age of onset, number of tender points, presence of Fabry disease like symptom, such as heart, kidney in fibromyalgia patients. However, there was a significant difference between patients with and without family history of symptoms which can be seen in Fabry disease, such as cerebral infarction, kidney failure, ischemic heart disease (19.7±1.7 AgalIU and 27.1±1.2 AgalIU, respectively, p=0.011, by Mann-Whitney U-test).
Conclusions Our findings showed α-gal A value has no significant difference between fibromyalgia patients and healthy controls, however, fibromyalgia patients with family history of Fabry disease like symptom showed significantly low level of α-gal A activity. These findings suggest there might be hidden patients with Fabry disease in chronic pain patients, such as fibromyalgia.
Zarate, et al. Lancet 2008. 372:1427-35.
Pisani, et al. BMC cardiovascular disorders. 2012. 12:39-43.
Disclosure of Interest None declared