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Clinical
Indications |
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Most
organic acids are cleared efficiently by the kidney and
urine is used for screening. Plasma is limited to
monitoring methylmalonic acidaemias.
The circumstances under which samples is collected is of
critical importance since in cases of an incomplete
metabolic block, characteristic metabolites may only be
detected at times of metabolic decompensation (e.g.
infection).
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Request
Form |
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Combined Pathology Blood form
(Yellow/Black or Blue for GP's) and Metabolic
screening questionnaire
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Availability |
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Analysed by referral laboratory if specific criteria
met.
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Specific
Criteria |
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Requests
must be accompanied by a completed Metabolic
screening questionnaire which has been authorised by a Consultant.
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Patient
Preparation |
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Samples
should be collected when the patient is unwell and
before treatment or a change in diet alters the pattern
of metabolites.
A fasting or pre-breakfast urine is required for
investigation of fatty acid oxidation defects.
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Turnaround
Time |
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2
weeks
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Specimen |
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Urine
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Volume |
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5.0
ml
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Container |
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White Capped
Universal
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Collection |
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Samples should be transported to laboratory immediately.
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Lab.
Handling |
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Separate into 2 aliquots and freeze at minus 20’C.
(UORG & send; NOORG & save)
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Causes for
Rejection |
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Unlabelled
sample.
Not meeting specific criteria for analysis.
Delay in sample reaching laboratory
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