A 27-year-old patient presents with the following laboratory results after a prolonged sub-acute illness.
Parameter |
Patient Value |
Adult Normal Range |
Sodium |
132 mmol/L* |
135 – 150 |
Potassium |
2.2 mmol/L* |
3.5 – 5.5 |
Chloride |
94 mmol/L* |
100 – 110 |
Bicarbonate |
28 mmol/L* |
22 – 27 |
Urea |
8.3 mmol/L* |
3.0 – 8.0 |
Creatinine |
236 μmol/L* |
70 – 120 |
Total Calcium |
5.04 mmol/L* |
2.15 – 2.60 |
Ionised Calcium |
2.6 mmol/L* |
1.1 – 1.3 |
Magnesium |
0.7 mmol/L |
0.7 – 1.1 |
Phosphate |
1.09 mmol/L |
0.70 – 1.40 |
Albumin |
37 g/L |
35 – 47 |
Total Bilirubin |
8 μmol/L |
4 – 20 |
g-Glutamyl transferase |
105 U/L* |
0 – 50 |
Alkaline phosphatase |
263 U/L* |
40 – 110 |
Alanine transferase |
76 U/L* |
< 40 |
Aspartate transferase |
48 U/L* |
< 40 |
a) List the ECG changes associated with the most striking biochemical abnormalities. (10% marks)
b) List three differential diagnoses. (15% marks)
c) List three management strategies. (15% marks)
Not available.
a)
The biochemical abnormalities which are the most "striking" here are the hypokalemia and hypercalcemia.
b)
What could be happening here? And more importantly, what meaning can we scry from the decision to call this illness both "prolonged" and "sub-acute"? It sometimes helps to itemise the abnormalities. They are:
So:
c)
List three management strategies. But for which disorder? You have three differential diagnoses. Do they mean a management strategy for each of the differentials, or three management strategies for the most likely differential? In which case, what if you chose poorly? Reader, it is safest to assume that the severe hypercalcemia is what they were asking about here, considering that the management strategies for the hypokalemia will largely consist of potassium replacement, and to test this spinal reflex couldn't possibly have been the objective of a final-level exam question.
So, the management options for hypercalcemia are:
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Beall, Douglas P., et al. "Milk-alkali syndrome: a historical review and description of the modern version of the syndrome." The American journal of the medical sciences 331.5 (2006): 233-242.
Van Der Plas, W. Y., et al. "Secondary and tertiary hyperparathyroidism: a narrative review." Scandinavian Journal of Surgery 109.4 (2020): 271-278.
Bukowczan, J., et al. "Gitelman’s syndrome presenting with hypercalcaemia due to severe primary hyperparathyroidism." Endocrine Abstracts. Vol. 29. Bioscientifica, 2012.