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Revise with quality questions and detailed explanations
Demo Question
Serum calcium levels are influenced by a number of factors, including many hormones.
Which of the following scenarios would naturally occur in a normal, healthy individual as a response to hypocalcaemia?
Decreased kidney phosphate reabsorption, high PTH, low calcitonin
High calcitonin, low PTH, raised thyroid hormone
High thyroid hormone, high PTH, high calcitonin
Increased osteoblast activity, high PTH, low calcitonin
Increased osteoclasts activity, low PTH, raised calcitonin
Key learning points
A perforated appendix implies that peritonitis occurred which increases the risk of future adhesions leading to bowel obstruction.
Explanation
PTH levels rise in response to hypocalcaemia, promoting decreased phosphate reabsorption at the kidneys. Serum calcium is found freely in an ionised form (50%) but also albumin bound (40%) and complexed (10%) with compounds such as phosphate. As such decreased serum phosphate will increase the availability of ionised calcium, the bioactive form. Calcitonin would be low in hypocalcaemia.
PTH levels rise in response to hypocalcaemia, promoting decreased phosphate reabsorption at the kidneys. Serum calcium is found freely in an ionised form (50%) but also albumin bound (40%) and complexed (10%) with compounds such as phosphate. As such decreased serum phosphate will increase the availability of ionised calcium, the bioactive form. Calcitonin would be low in hypocalcaemia.
