John Harrop wrote:
>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!
I think this case is very illustrative: The laboratory has discontinued the
use of ionized calcium because they could not justify the running costs.
But this single case has caused:
1) Several samplings and measurements of serum albumin and total calcium
2) (Repeated?) measurement(s) of serum phosphate
3) Measurement of urinary creatinine and alkaline phosphatase
4) Measurement of serum 25-OH Vitamin D
5) (Repeated?) measurement(s) of serum PHT
6) Probably also other tests not mentioned
7) A great number of hours not only for the clinical chemist but also for
the obstetrcian
For the cost of all these test and all this time you could have done several
hundreds of tests for ionized calcium!
The pregnancy apparently proceeds completely normal, and I strongly suspect
ionized calcium to be normal in this patient and that all reports on
"pregnancy hypercalcaemia" are artifacts, caused by an increase of
calcium-complexing agent(s) during pregnancy.
As far as I know, nobody has found ionized calcium to be increased during
pregnancy and, until otherwise has been proved, you should suspect all cases of
increased total or albumin-corrected calcium during pregnancy to be caused
by artifacts.
I should strongly recommend measurement of serum ionized calcium in this
case! If not done locally, send the sample to a another laboratory. Take
the sample in a plain vacuum tube, and NEVER REMOVE THE CAP!!!
Such samples are stable for at least 4 days, which is sufficient for sending
to any laboratory in the world.
Best wishes
Mr Sten Öhman, PhD
-----------------------------------------------------
From: Mr Sten Öhman, PhD
Postal address: p.o. Box 133, S-590 70 Ljungsbro, Sweden
E-Mail address: [log in to unmask]
Phone: int: +46 13 219020, nat: 013-219020
Fax: int: +46 13 219021, nat: 013-219021
Personal home page: http://hem1.passagen.se/stoh7971/
Company home page: http://www.elfinilab.se/
------------------------------------------------------
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|