Nandita has been diagnosed with osteomalacia. The results from recent blood tests are given below.
Analyte Patient result Reference range Units
Serum adjusted Ca 2.0 2.1 – 2.6 mmol/L
Serum intact PTH 7.5 1.6 – 6.9 pmol/L
Serum 25(OH)D 15 >50 nmol/L
Using this case study as an example, critically discuss and evaluate the biochemical investigation of vitamin D deficiency. Your answer should include an explanation of why the analytes listed above are measured and an evaluation of the methods used.
A 40-year-old woman went to see her GP because she had gained 12 kg in weight over the last year. Her other symptoms included headaches, generalized weakness, irregular and infrequent menstrual periods and a slight rounding of the face. Her pulse rate was 90 beats per minute and her blood pressure was 160/100 mmHg. Thyroid function tests and a prolactin test, performed in the last few months, showed normal results.
The doctor ordered additional tests and the results are shown below;
Analyte Patient result Reference Range Units
Sodium (Na+) 140 130-145 mmol/L
Potassium (K+) 3.5 3.5-5 mmol/L
Glucose 12 <11 mmol/L
Creatinine 125 60-120 µmol/L
Cortisol 1000 <200 nmol/L
Using the case study and biochemical data, explain your differential diagnosis in this patient and what causes this condition. In your answer, explain the further tests required to differentiate between different forms of this endocrine condition.
