The Challenges of Hypoparathyrodism in Roux en Y gastric bypass Patients; A call for awareness and a novel therapeutic strategy

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 234-256-Bone & Calcium Metabolism: Clinical Trials & Case Series
Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-248
Muhammad K Ahmed*, Guilherme M Campos, Vanessa Rein and Dawn Belt Davis
University of Wisconsin, Madison, WI
Background: Hypoparathyroidism (HP) is a known complication of total thyroidectomy (TT). With high volume endocrine surgeons the acceptable risk of definitive HP is around 0.7% (1).  This is an acceptable risk in a normal population. The treatment of HP requires ingestion and absorption of high doses of calcium and vitamin D. A large number of patients are now undergoing Roux en Y gastric bypass (RYGB) which results in malabsorption of macro and micronutrients. Therefore, the combination of HP and RYGB can lead to persistent and recurrent severe hypocalcemia.

Clinical Cases: 1. A 51 year old women underwent TT in 2001 for bilateral papillary thyroid CA. Post-TT she developed HP and was maintained on 640 mg elemental Ca daily. She underwent RYGB in 2007. She required over 14,400 mg of elemental Ca daily, and needed intravenous and gastrostomy tube administration. We also treated her with rPTH, which led to severe bone pain. High dose oral Ca resulted in hypercalciuria and azotemia. She underwent laparoscopic reversal of RYGB in 2011. She is now maintaining Ca levels with 1200 mg of elemental Ca daily.

2. A 28 year old woman underwent RYGB in 2009 and then had TT in 2012 for Hashimoto’s thyroiditis with goiter causing compressive symptoms. Post-TT she developed HP. We were unable to maintain serum Ca levels with high dose oral therapy. rPTH was not approved by her insurance. After multiple hospital admissions/ER visits and frequent IV calcium infusions, laparoscopic reversal of RYGB was performed. Now she is maintaining Ca levels with 600 mg elemental Ca daily.

2.  A 32 year old woman underwent RYGB in 2004. She had TT in 2012 for bilateral papillary thyroid CA. Post-surgery she developed HP. She has had several admissions and IV calcium infusions. She is maintaining Ca levels, but requires 13,800 mg elemental Ca daily.

Conclusions: We propose that 0.7% risk of definitive HP post thyroidectomy is an unacceptable risk in the bariatric surgery population.  Therefore total thyroidectomy should be avoided in patients with RYGB and, if necessary, should be performed by experienced surgeons after obtaining informed consent regarding this unique complication. In addition, patients considering RYGB need to be carefully screened for history of TT and/or HP. Finally, we show that reversal of gastric bypass is a promising treatment option for these complex patients.

(1) Zambudio AR, et al., Ann Surg. 2004 July; 240(1): 18-20.

Nothing to Disclose: MKA, GMC, VR, DBD

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