All cause diarrhea except;: (A) Diabetes, (B) Hypercalcemia, (C) Hypehyroidism, (D) Irritable bowel syndrome
Answer is B. Hypercalcemia increases the tone of sphincters of the gut leading to refractory constipation. Autonomic dysfunction in diabetes explains the diarrhea. Due to sympathetic activity increase in thyrotoxicosis there is a reduction in small bowel transit time explaining the diarrhea. IBS has variable presentation between diarrhea and constipation