Hypocalcemia and Hypercalcemia Quiz

Calcium Disorders

• Diagnosis and management of calcium disorders is the focus of the study.
• RCSI (Royal College of Surgeons in Ireland) developed the materials.

Learning Outcomes

• The learning outcomes help guide the study.
• Students will define hypercalcemia and hypocalcemia.
• Students will explain the pathophysiology of both conditions.
• Students will identify cardinal symptoms and signs of both conditions.
• Students will explain the cause of each symptom and sign in each condition.
• Students will identify the differential diagnosis for both conditions.
• Students will outline the principles for investigating and managing these disorders.

Learning Outcome 1

• Hypercalcemia is a serum calcium level greater than 2.6 mmol/L.
• Hypocalcemia is a serum calcium level less than 2.2 mmol/L.
• Corrected calcium levels account for albumin levels.

Learning Outcome 2

• Calcium homeostasis is regulated by parathyroid hormone (PTH) and vitamin D.
• Calcium regulation occurs through: bone turnover, intestinal absorption and renal excretion.

Learning Outcome 2 (Continued)

• PTH is secreted by the parathyroid glands stimulated by low calcium levels in the blood.
• PTH increases bone resorption, intestinal absorption and reduces calcium loss in the urine to increase calcium in the blood.

Learning Outcome 3

• Symptoms and signs of hypercalcemia might be asymptomatic, include bone pain, pathological fractures, kidney stones, and gastrointestinal issues like abdominal pain, nausea, vomiting, constipation and pancreatitis, as well as psychological symptoms like confusion and lethargy.

Learning Outcome 4 (continued)

• In hypocalcemia symptoms might be asymptomatic, include acute symptoms like tetany, papilledema and seizures, and chronic symptoms like ectodermal changes, cataracts, basal ganglia calcification and extrapyramidal disorders.

Learning Outcome 4(continued)

• Symptoms in hypercalcemia are caused by the increase in calcium levels affecting bone, muscle contraction and function, nervous system function, coagulation cascades and intracellular signaling mechanisms.
• Symptoms in hypocalcemia result from the decrease in calcium levels leading to neuromuscular excitability, affecting nerve function and causing muscle cramps, spasm and tetany, as well as cardiac manifestations.

Learning Outcome 5

• Hypercalcemia differentials: Primary hyperparathyroidism, malignancy, vitamin D excess (supplements, sarcoidosis, tuberculosis), renal disease, drugs (lithium, thiazide diuretics), familial hypocalciuric hypercalcemia, and dehydration.
• Hypocalcemia differentials: Hypoparathyroidism, vitamin D deficiency, postsurgical, autoimmune hypoparathyroidism, inherited disorders like familial hypocalcemia, infiltrative disorders (haemochromatosis, Wilson's disease), and metastatic diseases.
• (Further factors for hypocalcemia: Vitamin D deficiency, chronic kidney disease, hyperphosphatemia, osteoblastic metastases and acute pancreatitis)

Learning Outcome 6

• Investigation and management of calcium disorders need to consider underlying causes like drugs, kidney disease or even genetic predisposition.
• The investigation should involve evaluating PTH levels and consider imaging and other tests.
• Treatment varies depending on the specific cause and severity of the condition.

Hypercalcemia Investigation

• Initial steps include verifying serum calcium and measuring PTH.

Hypocalcemia Investigation

• Testing serum calcium and measuring PTH are initial steps.
• Further tests to investigate for underlying causes.

Hypercalcemia Management

• Prevention involves regularly reviewing medications and treating underlying conditions.
• Management is based on the severity and underlying cause, with mild cases potentially needing only monitoring and moderate cases avoiding exacerbating factors.
• Severe cases need aggressive therapy including IV isotonic saline, calcitonin, and bisphosphonates.

Hypocalcemia Management

• Prevention includes regularly reviewing medications and treating underlying causes
• Treatment varies based on severity, with severe cases requiring significant interventions like IV calcium while milder cases can involve oral calcium.

Additional Key Points

• Corrected calcium levels are vital to account for varying albumin levels.
• Serum calcium levels should be verified with corrected calcium levels.
• The underlying causes of either condition need to be addressed.
• The severity of the condition dictates immediate response and treatment choices.

Resources

• UpToDate
• Geeky medics