Porphyrin, Blood

Diagnostic Use

Clinical suspicion of acute or non-acute porphyria.

May include otherwise unexplained abdominal pain, neurological or psychotic features, skin lesions.

May occasionally be requested as a corroborative test for lead poisoning.

Department

Lipids/Trace Metals

Delphic Registration Code

PORB

Laboratory Handling

Phlebotomy

Whole blood protected from light

Separating

whole blood protected from light to Trace metals fridge

Synonyms

EPP
Erythrocyte Protoporphyrin
FEP
Free Erythrocyte Protoporphyrin
Protoporphyrin IX

Turnaround Time

1 week

Test Code

3476

Specimen Type

• Whole Blood

Specimen Requirements

Tube/Container Type:

Preferred

• Lithium Heparin - Non-gel (Green Cap)

Preferred Sample Volume (ml)

1

No of Samples Required

1

Paediatric Specimen Requirements

Tube/Container Type:

Preferred

• Lithium Heparin - Non-gel (Green Cap)

Preferred Sample Volume (ml)

0.2

Additional Specimen Information

Protect from light.

Aliquot Instructions

Sample Type

• Whole Blood

Minimum Volume (ml)

0.2

Transport to Lab

Chilled (2 - 8 degrees Celsius)
If overnight - Chilled (2 - 8 degrees Celsius)

Additional Referral/Aliquot Information

Protect from light. Fridge

Interpretation

Raised blood porphyrins may indicate underlying porphyria, in particular the non-acute erythropoietic protoporphyria (EPP), a childhood onset photosensitive disorder.
In EPP, plasma will show a fluorescence emission peak at 632nm, which is highly specific.

If EPP is suspected, it is important to send all samples – blood, urine and faeces protected from light for full evaluation which may include HPLC profiling. FECH genotyping is also available.

More commonly, blood porphyrins are raised in the context of iron deficiency as the disorder affects the final enzyme in the haem pathway, ferrochelatase which incorporates iron into protoporphyrin to form haem. Lead poisoning also leads to raised zinc protoporphyrin (blood porphyrins).

Note that a raised urine PBG is the diagnostic hallmark of an acute attack of porphyria.
A negative urine PBG during an acute symptomatic episode excludes acute porphyria as the cause.

Reference Intervals

Expected to be not raised.

Test Method

Fluorimetry

Non-Funded Test Cost

$15.12 (Exclusive of GST)

Billing Code

3476

Additional Costing Information

NB: EPP is an abreviation Erythrocyte Protoporphyrin.

For adequate screening tests for porphyria we require:

Blood: 2-5 ml heparinised blood (T34)
Urine: 10-15 ml fresh random specimen
Faeces: A stool minimum 10 g (walnut size)
Specimens should be wrapped in foil, placed in a paper bag and not exposed to direct sunlight.
Urgent testing by arrangement.

Contact Information

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