This is the diagnosis your endocrinologist may give you if your blood calcium and parathyroid hormone aren’t massively high or he doesn’t have the guts to send you to an endocrine surgeon for surgery. He may also carry out a calcium creatine clearance test and possibly a 24hr urine calcium test. If you’re not peeing out masses of calcium in your wee wee then I’m afraid your endocrinologist may tell you have FHH caused by a genetic mutation on your calcium receptor gene.
Your calcium receptor is like a calcium thermostat – the mutated gene means your thermostat is set too high (or should that be higher than non-mutants).
In FHH your blood calcium runs ‘naturally higher’ than normal people – so a slightly higher than normal blood calcium is normal for you and will not give you the symptoms of Primary Hyperparathyroidism – foggy brain, joint pain, muscle pain, osteoporosis, thirst, constipation etc.
(But I do have these symptoms Mr. Consultant Endocrinologist – ‘shut up, I’m the expert here – you couldn’t possibly be suffering form these symptoms with only a slightly abnormal blood calcium level’ (Note from blog owner: My consultant didn’t actually say this but he probably wanted to!))
Familial Hypocalciuric Hypercalcemia (FHH) is rarer than hens teeth (erm but hens don’t have teeth) it’s a few thousand times rarer than Primary Hyperparathyroidism.
The golden rule of medicine is test for and diagnose the statistically most probable disease which is most likely to cause the symptoms the patient presents with. This particular gem of wisdom is thrown out of the window when it comes to diagnosing Primary Hyperparathyroidism.
FHH is the last refuge of the endocrinologist who doesn’t want to send you to a surgeon because your calcium levels and Parathyroid hormone (PTH) are high but not too high.
If you have symptoms and occasional or permanently high blood calcium along with an inappropriately high PTH then the chances are that you have Primary Hyperparathyroidism.
So to recap Familial Hypocalciuric Hypercalcemia (FHH) is rare, rare, rare.
Jesus, Mary and Joseph on a bicycle FHH wasn’t even discovered by medical science until the 1970’s – when some nosey medical scientist gene hunter type happened upon a freaky family of mutants with a wonky calcium sensor gene.
Thanks to this family and their wonky genes the rest of us potential Primary Hyperparathyroidism patients are denied life changing surgery to remove a parathyroid tumour.
My endocrinologist thinks I may have FHH and so he has sent a sample of my blood off to test my genes.
So sitting in a lab somewhere in the Royal Halamshire Hospital genetic testing laboratory is a sample of my blood which will be spun to extract the white cells (red blood cells don’t have nuclei – so they don’t contain DNA).
It has now been over 13 weeks since my blood sample was taken – they do them in batches so they’ll be waiting for other FHH gene samples to arrive so they can do them all in the same day.
I am confident my endocrinologist will report a negative result – then it will be time to demand surgery!
If your endocrinologist has told you you have FHH (Familial hypocalciuric hypercalcemia) because your blood calcium is high, but not that high then he may be making an educated guess.
My endocrinologist told me I had FHH, but I didn’t I had a parathyroid tumour causing Primary Hyperparathyroidism, which made me very unwell over the past 10 years.
FHH is extremely rare!! Your endocrinologist will probably never see anyone with the genetic defect.
Take my advice, the only proof of FHH is via a genetic test – get your endocrinologist to prove it to you with a genetic test.
I had the test and it was negative – because I had a nasty little 2cm parathyroid tumour in my neck and it’s now in a jar of formaldehyde somewhere.