PTH and Hypocalcemia: Hungry bone syndrome (HBS), rarely named “bone starvation syndrome”, severe hypocalcemia following parathyroidectomy (PTX) due to rapid drop of PTH after a previous long term elevated concentration and associated bone remineralization, impairs the outcome of underlying parathyroid (PT) disease by affecting the quality of life, prolonged hospitalization stay, and increased post-operatory re-admission rate [1,2,3].