Maayan C, Bar-On E, Foldes A J, Gesundheit B, Pollak R Dresner
Department of Pediatrics, Hadassah University Hospital, Mount Scopus, Hebrew University Hadassah Medical School, Jerusalem, Israel.
Osteoporos Int. 2002 May;13(5):429-33. doi: 10.1007/s001980200050.
Familial dysautonomia (FD) patients suffer from multiple fractures and have reduced bone pain, which defers the diagnosis. The pathogenesis of bone fragility in FD is unknown. This study aimed to characterize bone mineral metabolism and density in FD. Seventy-nine FD patients aged 8 months to 48 years (mean age 13.9 +/- 10.4 years, median 12.3) were studied. Clinical data included weight, height, bone age, weekly physical activity and history of fractures. Bone mineral density (BMD) of the lumbar spine (n = 43), femoral neck (n = 26), total hip (n = 22) and whole body (n = 15) were determined by dual-energy X-ray absorptiometry. Serum 25-hydroxyvitamin D3, osteocalcin, bone alkaline phosphatase (B-ALP), parathyroid hormone and urinary N-telopeptide cross-linked type 1 collagen (NTx) were determined in 68 patients and age- and sex-matched controls. Forty-two of 79 patients (53%) sustained 75 fractures. Twenty-four of 43 patients had a spine Z-score < -2.0, and 13 of 26 had a femoral neck Z-score < -2.0. Mean femoral neck BMD Z-score was lower in patients with fractures compared with those without (-2.5 +/- 0.9 vs -1.5 +/- 1.0, p = 0.01). Mean body mass index (BMI) was 16 kg/m2 in prepubertal patients and 18.4 kg/m2 in postpubertal patients. Bone age was significantly lower than chronological age (75.5 vs 99.3 months in prepubertal patients, p < 0.001; 151 vs 174 in postpubertal patients, p < 0.05). NTx and osteocalcin levels were higher in FD patients compared with controls (400 +/- 338 vs 303 +/- 308, BCE/mM creatinine p < 0.02; 90 +/- 59.5 vs 61.8 +/- 36.9 ng/ml, p < 0.001, respectively). B-ALP was lower in FD patients compared with controls (44.66 +/- 21.8 vs 55.36 +/- 36.6 ng/ml, p < 0.04). Mean spine Z-score was significantly lower in physically inactive compared with active patients (-3.00 +/- 1.70 vs -1.77 +/- 1.3, respectively, p = 0.05). We conclude that fractures in FD patients are associated with reduced BMD. FD patients have increased NTx and osteocalcin. Contributing factors include reduced BMI, failure to thrive and reduced physical activity. Preventive therapy and early diagnosis are essential.
家族性自主神经功能障碍（FD）患者易发生多处骨折且骨痛减轻，这会延迟诊断。FD患者骨脆性的发病机制尚不清楚。本研究旨在描述FD患者的骨矿物质代谢和骨密度特征。对79例年龄在8个月至48岁（平均年龄13.9±10.4岁，中位数12.3岁）的FD患者进行了研究。临床数据包括体重、身高、骨龄、每周体育活动量和骨折史。采用双能X线吸收法测定了43例患者的腰椎、26例患者的股骨颈、22例患者的全髋和15例患者的全身骨密度（BMD）。对68例患者以及年龄和性别匹配的对照组测定了血清25-羟基维生素D3、骨钙素、骨碱性磷酸酶（B-ALP）、甲状旁腺激素和尿I型胶原交联N-端肽（NTx）。79例患者中有42例（53%）发生了75处骨折。43例患者中有24例腰椎Z值＜-2.0，26例患者中有13例股骨颈Z值＜-2.0。与未发生骨折的患者相比，发生骨折的患者股骨颈平均BMD Z值更低（分别为-2.5±0.9和-1.5±1.
