S. C. Oltmann1, T. M. Madkhali2, H. Chen2, R. S. Sippel2, D. F. Schneider2 1University Of Texas Southwestern Medical Center,Department Of Surgery,Dallas, TX, USA 2University Of Wisconsin,Department Of Surgery,Madison, WI, USA
Introduction
Patients with end stage renal disease (ESRD) suffer from hypocalcemia and secondary hyperparathyroidism (SPHPT). Therefore, defining recurrence or persistence after parathyroidectomy (PTX) using calcium values alone becomes problematic. The 2009 Kidney Disease: Improving Global Outcomes (KDIGO) guidelines provide target ranges for serum calcium (Ca: 8.4 to 10.2 mg/dL), phosphorous (Phos: 2.5 to 4.6 mg/dL) and parathyroid hormone (PTH: 130 to 600 pg/mL) levels for those patients with ESRD requiring dialysis. The study purpose is to see if KDIGO targets, which often determine need for initial surgical intervention, are also appropriate to define disease persistence or recurrence in SHPT.
Methods
A retrospective review of a prospective endocrine surgery database was performed. Included patients had SHPT, due to ESRD, were on dialysis and underwent PTX. Ca, Phos and PTH were classified as below, within, or above the KDIGO targets at various pre and post-operative time points.
Results
Between 2000 and 2013, 36 patients with SHPT met inclusion criteria. Mean age was 44±SEM2.1 years. 42% were females. Subtotal PTX was performed in 89%, with 11% undergoing total PTX. Follow-up time was 54±7 months. 8 patients (22%) required additional procedures to address recurrent and/or persistent SHPT. 28 patients (76%) of were alive at last follow-up, with estimated survival at 1 year (100%), 2 years (94%), 5 years (82%) and 10 years (65%) calculated. Sensipar use at last follow-up was noted in 2 patients (5%). At time of last follow up, 46% of patients had Phos levels, and 17% had PTH levels still above the KDIGO ranges (Table).
Factors associated with need for re-operation were assessed. Patient PTH levels within or above target at time of first post-operative visit were associated with a higher rate of reoperation(p<0.01). At the time of last follow-up, Ca levels with respect to KDIGO ranges were not associated with higher reoperation rates (p=0.33), but higher Phos (p=0.054), PTH (p<0.001) levels were associated with increased rates of reoperation.
Conclusions
Of the various KDIGO laboratory indices for patients with ESRD on dialysis with SHPT, PTH and Phos levels above target were associated with additional surgical intervention. However, a significant number of patients had laboratory indices above suggested ranges at last follow-up, suggesting many more patients residual or recurrent disease than have undergone reoperation, suggesting that there are many patients who may benefit from more aggressive surgical or medical management.
