一个66岁的女性面对nontraumatic慢性dull-aching下腰痛症状恶化前一年。疼痛影响她走,“鸭步”来避免痛苦。有时疼痛会辐射到右腿大腿前部和侧面而不是过去的膝盖。没有相关的感觉异常或重大弱点。她否认历史的癌症、体重减轻、发烧、发冷、或盗汗。没有历史的肾结石或骨折。她被治疗糖尿病和高血压。她的历史不清楚病因在1990年代的肺栓塞。外科1994年历史包括胆囊切除术,子宫内膜消融,1996年双边腕管手术。她对青霉素过敏导致皮疹,杜绝磺胺类引起腹部不适。 The patient reported remote history of smoking for 15 years, quitting 25 years ago. Family history was negative for bone disease. Physical exam was remarkable for her being overweight. She had a side-to-side waddle in her gait and slightly lifted her feet on walking. Straight leg raising test was negative. She did not have tenderness to percussion of the lower back but did have a gibbous at L-4. There was no back pain with movement. She had weakness at the iliopsoas and quadriceps bilaterally but no loss of sensation. An outside MRI of the lumbar spine showed an infiltrative lesion in the L-4 vertebra with collapse of the body (confirmed on repeat MRI at our institution, Figure
1)。CT扫描证实病理骨折骶溶解病变。骨骼扫描显示轻度放射性示踪剂摄取增加,骶和额外的吸收是在几个较低的胸肋骨双边,剑突,右上角股骨,头骨,暗示代谢性骨病。损伤骶hypermetabolic在PET扫描(图
2)。初始损伤的CT引导穿刺活检nondiagnostic证明只有骨头,纤维组织和软骨。实验室检测的低血清磷1.5 mg / dL (2.5 - -4.5 mg / dL)。额外的异常包括血清钙升高10.6 mg / dL (8.9 - -10.1 mg / dL),不合理的高甲状旁腺激素(素120 pg / mL (15 - 65 pg / mL),低1,25-dihydroxyvitamin D < 8 pg / mL (18 - 78 pg / mL),和温和的血清碱性磷酸酶升高162 u / L (45 - 115 u / L)。血清白蛋白是正常的在4.0 g / dL (3.5 - -5.0 g / dL),血清肌酐1.2 mg / dL (0.6 - -1.1 mg / dL),人体内25 -羟维生素D和正常31 ng / mL (25 - 80 ng / mL)。她弗兰克phosphaturia,尤其是她的血清磷水平(772毫克,正常的0 - 1099毫克)。24小时尿钙低10毫克(20 - 275毫克)。血清和尿蛋白电泳immunofixation是正常的。促甲状腺激素(TSH)是正常的在2.12个人/ L(0.3 - -5.0个人/ L)。甲状旁腺扫描是正常的。 Plasma FGF-23 from a peripheral vein was significantly elevated at 3,500 RU/mL (<180 RU/mL), confirming TIO. Oral phosphate supplementation and calcitriol were prescribed. She was subsequently lost to followup from our medical center for two years, and when she returned, she reported that she had internal fixation with a rod placement for a spontaneous right femur fracture. She also had deep pain in her left thigh and was told by a local provider that she had a “brown tumor” in the left femur based on plain radiographs. She had not been taking phosphate supplements or calcitriol on a regular basis. Repeat laboratory investigations continued to show a significantly low phosphorus of 1.4 mg/dL (2.5–4.5 mg/dL), high serum calcium of 10.6 mg/dL (8.9–10.1 mg/dL), elevated PTH of 229.1 pg/mL (10–65 pg/mL), and serum creatinine of 0.9 mg/dL (0.6–1.1 mg/dL). Plasma FGF-23 level remained significantly elevated at 4,460 RU/mL (<180 RU/mL). A repeat CT guided needle biopsy of L-4 showed a low grade spindle cell neoplasm with positive FGF-23 mRNA expression by RT-PCR (Figure
3),确认混合phosphaturic间质肿瘤的诊断(PMT)。她经历了自发离开peritrochanteric骨折髓内的要求放置设备。病人然后选择手术涉及的前切除骶椎体完成总spondylectomy在脊髓水平,以及corpectomy。切除标本的病理证实了梭形细胞肿瘤与PMTMCT一致。手术切除后六个月,她在日常生活活动是独立的,但使用沃克移动行走和右脚下降由于一些困难。她规定的物理治疗。后续实验室检测显示正常血清磷2.5 mg / dL (2.5 - -4.5 mg / dL)和钙9.6 mg / dL (8.9 - -10.1 mg / dL)。甲状旁腺素是619 pg / mL (10 - 65 pg / mL)。这是最小的磷酸没有骨化三醇的补充。重复等离子FGF-23水平仍然较高,但大大减少到422俄文/毫升(< 180俄文/毫升)。