I heard yesterday from the US that in fact C-peptide assays were actually
done on the samples from laboratory staff which yielded spuriously high
insulin assays, and the results from these were low, as in the case of the
samples from the child taken into care.
This means that high insulin assays coupled with low c-peptide content do
not necessarily mean exogenous administration of insulin.
Compliance with standard operating procedures cannot be guaranteed and care
proceedings are too easily conducted using flawed data, behind the closed
doors of the family courts where independent scrutiny is impossible.
This is not exclusive to the US and similar cases have occurred in the UK.
Brian Morgan
.
Brian Morgan wrote:
> A case of a 3 week old 3 week premature hypoglycemic white female in
> the US yielded high insulin assays in conjunction with a very low
> c-peptide results which gave rise to concerns about exogenous insulin
> administration. The father is diabetic.
>
> However, later media investigation yielded information that the blood
> samples for insulin assay had been left on a window ledge in open
> sunlight for significant periods, prompting an investigation by experts
> retained by a film production company into the effect of holding blood
> samples from their own lab. staff at elevated temperatures for differing
> periods of time before spinning down.
>
> Bloods left at temperatures of 98 deg F or 120 F resulted in high
> insulin assays similar to some of the results in the child's case - one
> of them in excess of 500,000 micro units/ml - compared with assays in
> single or double figures from bloods left at 85 deg F or less for the
> same periods of time.
>
> There was some uncertainty over the storage of the spun down samples -
> whether they were frozen in dry ice or not - so tests were redone with
> all samples being frozen appropriately, and this time assays were
> 'normal'.
>
> None of the experimental work, sadly, included assays of c-peptide in
> the lab staff blood.
>
> There is unsurprisingly some interest in the US as to what really was
> going on in the original case - were the high insulin assaays
> artefactual - might the very low c-peptide result - (0.05ng/ml) - also
> be artefactual - is there a plausible explanation for these huge
> variations in insulin assay other than the received wisdom that high
> insulin - low c-peptide automatically means exogenous insulin?
>
> Do any list members anywhere in the world have observations - is insulin
> assay really so critically dependent on the correct storage of samples?
>
> Can diagnosticians be certain standard operating procedures have been
> followed when faced with such extraordinary results?
>
> Brian Morgan
> Freelance Journalist
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