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From: Robertson, Stuart
Sent: 09 May 2001 17:44
To: 'Jeffrey Barron'
Subject: RE: Corrected calcium in childhood
I don't quite follow this. Using your formula, if the albumin is higher than
40 g/L then corrected calcium should be LOWER than measured calcium.
Some labs only correct calcium if the albumin is lower than 40 g/L.
I know this formula is used as a rough correction by many labs (I think it
was first published in a BMJ editorial over 20 years ago), but the
correction will depend on the assay methods you are using (eg BCG or BCP for
albumin).
To make the appropriate correction for your assays, you really need to look
at your own data and calculate the regression of calcium on albumin.
See Ann Clin Biochem 1996; 33: 55-62
Stuart Robertson
Biochemistry Dept
Hull Royal Infirmary
Hull
HU3 2JZ
Phone 01482-607707
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From: Jeffrey Barron [SMTP:[log in to unmask]]
<mailto:[SMTP:[log in to unmask]]>
Sent: 09 May 2001 17:17
To: [log in to unmask]
<mailto:[log in to unmask]>
Subject: Corrected calcium in childhood
We give a corrected serum calcium for both adults and children using
the formula
Corrected serum calcium = Total calcium +(( 40-Albumin) x 0.02 )
The paediatric endocrinologist has noted that a number of children
have a normal total calcium with a raised corrected calcium, due to a high
albumin.
I require advice as to whether we should continue to give a
corrected calcium for children because the formula is probably adult
derived. Is there another formula for children ?
Jeff
Dr Jeffrey Barron
Consultant Chemical Pathologist
St Helier Hospital
Carshalton
Surrey SM5 1AA
UK
Tel UK 20 8296 2660
Fax UK 20 8641 2633
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