Several comments were made a month or so ago about this case of
hypercalcaemia in pregnancy. A copy of the original posting is appended to
this e-mail for ease of reference.
*Update*:
The pregnancy proceeds uneventfully. She is now 25 weeks. Her latest
albumin adjusted calcium is 3.18 mmol/L, now the highest it has been. Her
phosphate is 0.86 mmol/L (0.8-1.45). Urine creatinine and alkaline
phosphatase are normal.
Following suggestions here, we went back and got 25-OH vitamin D done on
serum at about 14 weeks pregnant. The level was 109 nmol/L (15-100,
non-pregnant reference range). I assume this result is compatible with
oestrogen-induced rise in vitamin D binding protein?
Other findings to report now :
1. The patient says she took one multivitamin tablet (from Boots) and
one cod liver oil capsule (from a Health Food shop) daily prior to her
pregnancy but stopped these as soon as she knew she was pregnant.
2. She has developed two patches of vitiligo on her cheek.
3. We have repeated PTH, 25-OH vitamin D and 1,25-diOH vitamin D.
The repeat PTH was less than 2 ng/L ( Immulite). The vitamin D results are
awaited.
4. She is having a steroid suppression test at the moment.
I will report back when there is something further to say. With regard to
some of the previous correspondence:
a) Geoff Lester: We felt her 24-hr urinary calcium and previously
normal
serum calcium excluded FHH. We have not done urine calcium studies. Is
that good enough? Also as Trevor Gray intimated we would not have
pregnancy reference ranges for indices of calcium excretion.
b) Brian Payne: No, she was not pregnant in 1988 and the normal
calcium then was albumin adjusted.
c) Swami: I am afraid we have still not done her pH or bicarbonate.
e) Tony Mak: I guess her suppressed PTH now virtually excludes
"usual" primary hyperparathyroidism, although the PTH originally was not
completely suppressed. As for the references regarding PTHRP from
placenta or mammary gland causing hypercalcaemia, do you think we should
repeat the PTHRP? How else might we investigate this further, if at all?
f) Sten Ohman: No we do not have ionised calcium results. We
discontinued
use of our ionised calcium analyser about 5 years ago, not being able to
justify the running costs against the clinical usefulness ........ but say
no more ........
Note bene: this is not an attempt to rekindle the ionised calcium versus
albumin adjusted calcium debate!
g) Snail mail discussion of this case led to one correspondent
describing a pregnant patient with hypercalcaemia which appeared well
documented, but relatively short-lived (a few days), of unknown aetiology,
with a question as to whether such hypercalcaemia in pregnancy may be more
common than we realise. We just don't measure calcium very often in
pregnancy. Even if that is the situation the case currently under
discussion does seem rather different.
Thanks for all your comments which have been most instructive, to me at
least! I only hope our patient is "telling the truth" about her use of
vitamin pills and the like!
The physician involved & myself look forward to any further guidance.
John Harrop
The physician concerned and myself look forward to any further guidance.
John Harrop
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*The original presentation was as follows:*
<
Hypercalcaemia and pregnancy - advice needed!
The patient is 31 years old. She presented to her GP when about 8 weeks
pregnant.
A blood sample sent in by her GP showed an albumin-adjusted calcium of 3.02
mmol/L. She had developed some nausea and sickness, and had sought her
GPs advice. He did not think she merited admission to hospital but did
arrange some blood tests.
Her U&Es, LFTs and glucose were normal. Phosphate was 1.01 mmol/L, and
alkaline phosphatase 135 IU/L (non-pregnant ref.range 90-260).
She was referred to a Consultant Endocrinologist. Examination was
unremarkable. It was felt that her nausea & vomiting were related to the
pregnancy rather than the moderate hypercalcaemia. Her calcium was noted
to have been 2.49 mmol/L in 1988. No biochemistry had been done since
then.
Investigations showed:
Alb-adjusted calcium 2.96 mmol/L
Phosphate 1.11 mmol/L
24h urine calcium 6.6 mmol (2.5-9.0)
TSH 1.38 mU/L (0.3 - 6.0)
Serum cortisol 420 nmoL/L at 0900h (190-690)
ACE 22 IU/L (up to 55)
PTH 11 ng/L (11-54)
Chest X-ray was normal.
She did not appear to have any dietary fads or fancies.
One week later her calcium was 2.83 mmol/L.
PTHrP was 0.3 pmol/L (normal up to 2.6).
Her nausea and vomiting has subsided.
The cause of her raised calcium remains unclear. In view of the reported
risks, especially to the foetus, of persisting hypercalcaemia through
pregnancy (although there have been some case reports indicating that this
may be overstated), we would welcome discussion, suggestions or advice
about any further investigation and/or management. This is a "real-time"
clinical problem - there is no final diagnosis.... yet!
>
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