1 Introduction
2 Anatomical location of parathyroid adenomas
3 Clinical features and pathophysiology
3.1 Genetic basis of PHPT and FHH
4 Diagnosis and management
5 Case 1: PHPT due to eutopic parathyroid adenoma
Investigations | Primary hyperparathyroidism | FHH | ||||
---|---|---|---|---|---|---|
Case 1: Eutopic parathyroid adenoma | Case 2: Eutopic parathyroid adenoma | Case 3: Eutopic parathyroid adenoma | Case 4: Ectopic parathyroid adenoma | Case 5: Syndromic PHPT | Case 6: CASR inactivating mutation | |
Age (years) | 72 | 43 | 75 | 68 | 39 | 43 |
Family history of hypercalcaemia | None | None | None | None | Under investigation | Mother and maternal grandmother* |
Calcium (mmol/l, mg/dl) | 2.80, 11.2 | 2.45, 9.8 | 3.00, 12.0 | 3.23, 12.9 | 3.23, 12.9 | 2.75, 11.0 |
PTH (pmol/l) | 12.8 | 10.2 | 10.7 | 42.1 | 37.6 | 4.4 |
Vitamin D (nmol/l) | 39 | 78 | 69 | 57 | 44 | 75 |
Phosphate (mmol/l) | 1.01 | 0.95 | 0.85 | 0.87 | 0.39 | 0.52 |
ALP (IU/l) | 116 | 54 | 92 | 80 | 71 | 18 |
Creatinine (mol/l) | 98 | 58 | 58 | 72 | 89 | 61 |
GFR (ml/min) | 50 | >60 | >60 | >60 | >90 | >90 |
CCCR (%) | 1.5 | 1.39 | 2.5 | 2.8 | 1.02 | 0.31 |
US (or CT) kidneys | No renal calculi | Renal calculi (on CT) | No renal calculi | No renal calculi | Renal calculi (on CT) | No renal calculi |
Lumbar spine BMD (T-score) | −2.3 | Z-score: −0.7 | −1.6 | −1.4 | Z-score: −0.7 | Z-score: +0.2 |
Femoral BMD (T-score) | −2.7 | Z-score: −0.3 | −2.6 | −2.5 | Z-score: −0.6 | Z-score: −1.3 |
Forearm BMD (T-score) | −1.9 | Z-score: −0.1 | −1.9 | −3.8 | Z-score: −0.5 | – |
US neck | Left inferior parathyroid adenoma | Left inferior parathyroid adenoma | No parathyroid adenoma identifiable† | No parathyroid adenoma identifiable | Right inferior double parathyroid adenomas | Not required |
99mTc-sestamibi-SPECT/CT | Left inferior parathyroid adenoma | Left inferior parathyroid adenoma | No parathyroid adenoma identifiable† | Mediastinal ectopic parathyroid adenoma | Right inferior parathyroid adenoma | Not required |
Genetic analysis | – | – | – | MEN1 | CASR frameshift variant‡ | |
Management | Left inferior parathyroidectomy | Awaiting parathyroidectomy | Right superior parathyroidectomy initially followed by left inferior parathyroidectomy | Left VATS thoracoscopic excision of parathyroid gland | Parathyroidectomy of double adenomas Referred to MEN1 clinic | Family genetic assessment |
6 Case 2: PHPT with normocalcaemic hyperparathyroidism
7 Case 3: PHPT due to an elusive eutopic parathyroid adenoma (not identifiable by ultrasound scan and 99mTc-sestamibi-SPECT/CT)
8 Case 4: PHPT due to ectopic parathyroid adenoma
9 Case 5: Syndromic PHPT
Fasting biochemical screening tests | Reference range | Results |
---|---|---|
Prolactin (mU/l) | 45–175 | 1630 |
IGF-1 (nmol/l) | 9.4–29.3 | 32.4 |
Glucose (mmol/l) | 4.1–6.0 | 5.7 |
Insulin (pmol/l) | – | 48 |
Gastrin (pmol/l) | 0–40 | >400 |
Glucagon (pmol/l) | 0–50 | 18 |
CART (pmol/l) | 0–129 | 58 |
Somatostatin (pmol/l) | 0–150 | 25 |
Chromogranin A (pmol/l) | 0–60 | 72 |
Chromogranin B (pmol/l) | 0–150 | 145 |
Pancreatic polypeptide (pmol/l) | 0–300 | 46 |
Vasointestinal polypeptide (pmol/l) | 0–30 | 6 |
Calcitonin (ng/l) | 0–11.8 | 3.2 |
24 h urine 5-HIAA (μmol/24 h) | 0–47 | 37 |
2-h OGTT | ||
Baseline: GH (μg/l), glucose(mmol/l), IGF-1(nmol/l) | 3.7, 4.9, 33.9 | |
GH at 30, 60, 90 and 120 min | 0.6, 0.2, 0.1, 0.1 | |
Glucose at 30, 60, 90 and 120 min | 13.2, 12.1, 11.0, 5.4 | |
Genetic analysis | ||
MEN1 | NM_130799: c.1256G > Tp.(Gly419Val) | |
Radiological investigations | ||
CT chest, abdomen and pelvis | 2 × 1.5 cm solid structure posterior to the right thyroid lobe suggestive of two parathyroid adenomas Bilateral non-obstructing renal calculi (2 mm) Bones appear sclerotic Spleen, pancreas and adrenal glands appear normal | |
Ultrasound neck | Two parathyroid adenomas in right thyroid lobe | |
DEXA | Osteopenia | |
99mTc-sestamibi-SPECT/CT | Right parathyroid adenomas | |
MRI pituitary with contrast | No pituitary adenoma identified | |
Oesophago-gastro-duodenoscopy | Ulcers at gastro-oesophageal junction | |
Visual field test | No VF defects |
10 Case 6: Familial hypocalciuric hypercalcaemia due to CaSR mutation
11 Case 7: Secondary hyperparathyroidism
12 Discussion
PHPT | FHH | |
---|---|---|
Age at presentation | Older | Younger |
Family history | ± † | +++ |
Symptoms | ++ | – |
Hypercalcaemia | +++ | ++ |
Hyperparathyroidism | +++ | ± |
Calcium/creatinine clearance ratio | >1% | <1% |
Vitamin D insufficiency | ++ | – |
Raised alkaline phosphatase | ++ | – |
Ultrasound scan | +++ | – |
99mTc-sestamibi-SPECT/CT | +++ | – |
Osteopenia/osteoporosis | ++ | – |
Renal calculi | ++ | – |
Peptic ulcers | + | – |
Curative parathyroidectomy | +++ | – |