Bruce Jancin, Denver Bureau
[Pediatric News 33(3):40, 1999. © 1999 International Medical News Group.]
Orthostatic intolerance is seen in both conditions, presumably because connective tissue abnormalities predispose to excessive venous pooling during upright posture. This explanation makes the observed association biologically plausible, Dr. Michael T. Geraghty said at the annual meeting of the American Society of Human Genetics.
Denver -- Chronic fatigue syndrome appears to be common among patients with Ehlers-Danlos syndrome, a connective tissue disorder characterized by joint hypermobility, hyperelastic skin, and connective tissue fragility.
According to other investigators, as many as one in nine people may have a mild variant of the connective tissue disorder. Other manifestations of the disorder may include acrocyanosis when limbs are in a dependent position, wide papyraceous scarring over bony prominences, ocular lesions, easy bruisability, and other vascular abnormalities.
It's too early to say how often the two conditions coexist, however, said Dr. Geraghty of Johns Hopkins University, Baltimore.
Dual-diagnosis patients may obtain symptomatic improvement using medications that address orthostatic intolerance by reducing venous pooling. Moreover, establishing the diagnosis of Ehlers-Danlos syndrome has added benefits, including a heightened awareness of potentially serious complications, improved detection of affected relatives, and avoidance of unnecessary diagnostic and surgical procedures.
Dr. Geraghty reported on 10 patients averaging 16 years of age who were evaluated both in the Hopkins chronic fatigue syndrome clinic and the genetics clinic. All met prevailing diagnostic criteria for both disorders. Diagnosis of chronic fatigue syndrome preceded that of Ehlers-Danlos by a median of 42 months in 9 of 10 patients.
The medical literature has historically underemphasized the easy fatiguability of patients with Ehlers-Danlos, as well as their common complaints of widespread muscle and joint pain. Indeed, all 10 patients in this series complained of varying degrees of pelvic, joint, and limb pain in the absence of articular swelling or erythema. Nine had a history of recurrent joint dislocations, requiring surgery in three cases, Dr. Geraghty noted.
All patients had abnormal results on orthostatic testing. Based upon the results of an upright tilt-table test or a 10-minute standing test, eight patients had postural tachycardia syndrome, six had neurally mediated hypotension, and four had both.
Several prior studies in patients with chronic fatigue syndrome have shown application of military antishock trousers results in symptomatic improvement, with prevention of orthostatic tachycardia and hypotension. It's logical that symptoms of chronic fatigue and orthostatic intolerance in patients with Ehlers-Danlos syndrome might respond to vasoconstrictors that reduce gravitational venous pooling, but this hypothesis awaits testing in randomized, controlled trials.
Before using these agents in patients with Ehlers-Danlos syndrome, however, the presence of an enlarged aortic root should be ruled out. It's not a common abnormality -- it was present in 1 of 10 patients in this series -- but it predisposes to a feared complication of the connective tissue disorder: dissecting aortic aneurysm, he said.