Objective: Multiple endocrine neoplasia type 1-related PHPT (MHPT) differs in many aspects from sporadic PHPT (SHPT). The aims of the study were to summarize the clinical features of Chinese MHPT and compare the severity of the disease with SHPT.
Design and methods: A total of 40 MHPT cases (27 sporadic, seven families) and 169 SHPT patients of Chinese descent were retrospectively analyzed. X-rays and ultrasound were used to assess the bone and urinary system. Dual energy X-ray absorptiometry (DXA) were performed to measure bone mineral density (BMD). The present study was approved by the local Ethics Committee.
Results: The mean age at diagnosis of PHPT in MHPT group was younger than SHPT group (45.0 vs 50.7 years, P=0.025). Compared with SHPT patients, MHPT patients showed lower prevalence of skeletal involvement (87.1% vs 57.5%, P<0.001) but higher prevalence of urolithiasis/renal calcification (40.2% vs 60.0%, P=0.024). MHPT patients showed higher phosphate level (0.84 vs 0.73 mmol/l, P<0.05) but lower ALP (103.0 vs 174.0 U/L, P<0.001) and PTH (4.0 vs 9.8×upper limit, P<0.001) levels than SHPT patients. There were no significant differences in BMD Z-scores at the lumbar spine and femoral neck between the two groups even after adjustment of age, sex, course of PHPT (P=0.829, 0.510 respectively). Compared with SHPT, the incidences of parathyroid hyperplasia and multi-glandular involvement were both higher in MHPT patients (both P<0.001). MEN1 gene mutations were detected in 27 MHPT cases. Nine mutations were novel, and one of which was deletion of exon 5 and 6.
Conclusions: MHPT patients showed more common kidney complications but less common skeletal involvement despite a milder biochemical presentation compared with SHPT patients. MEN1 mutation detection rate was 79.4% and nine mutations were novel.
14 May 2016 - 17 May 2016