Introduction: Hypocalcaemia is a potential post-thyroidectomy complication. Patients with previous Roux-en-Y Gastric Bypass (RYGBP) are at increased risk of symptomatic hypocalcaemia refractory to treatment. This complication is rare and there is not consensus on how to act.
Clinic case: Female with 34 years old, with a history of Obesity (BMI 45.7 kg/m2), submitted to RYGBP in 2013, with a total loss of 47 kg (current BMI 27.3 kg/m2). In October 2014, she had total thyroidectomy for nodular hyperplasia. Postoperative was complicated with symptomatic hypocalcaemia requiring calcium gluconate i.v. and early replacement therapy with calcium and vitamin D as an outpatient. Over the next 6 months she had five admissions in the Emergency Department due to hypocalcaemia, requiring calcium gluconate i.v. administration. For this reason was referred to our clinic in March 2015. After discussing the case with surgeons, due to difficulties in normalizing calcium levels (calcium of 7.1 mg/dl with calcium carbonate 31 500 mg/day and calcitriol 1.5 μg/day and calcium gluconate i.v. 3/3 weeks) decides to reverse the RYGBP in May 2015, which occurred without complications. There was only a partial improvement of the hypocalcaemia. In January 2016, she has calcium of 7.4 mg/dl with calcium carbonate 9000 mg/day, cholecalciferol 2400 UI/day. Phosphorus was 4.6 mg/dl (2.74.5) and PTH 4 pg/ml (1687).
Conclusions: This case shows that patients with hypoparathyroidism and RYGBP have a high risk of recalcitrant hypocalcaemia. For this reason, several authors have argued that performing thyroidectomy after RYBGP should be done after analysing benefits and risks. There are cases described in the literature that after medical treatment failure, the reversal of RYBG can be a solution, as it restores the absorption of calcium and vitamin D places, however we need randomized controlled studies.