Pathology Handbook

Porphyrins

Synonyms

 -

Clinical Indications

Clinical Presentation

Specimens

Comments

Acute neurological attacks(suspected AIP, VP, HCP)

Urine
Faeces
Blood

To exclude a current attack or to monitor known porphyria, urine alone is adequate. Urine screen is provided in-house.

Acute photosensitivity(suspected EPP)

Blood

Urine and faeces of no value.

Skin lesions (suspected PCT, VP, HCP or CEP)

Urine
Faeces
Blood

To monitor patients with PCT send urine only.

Request Form

Request on ICE

Relevant clinical information MUST be given

Availability

On request, if specific criteria met

Specific Criteria

Investigation suspected porphyria. The incidence of porphyria is such that an average District should contain about 20 patients with overt porphyria. The rate of diagnosis is much less than this and may be due to failure to suspect porphyria as a possible diagnosis.

Turnaround Time

3 weeks

Specimen

Blood (heparin and EDTA)

Early Morning Urine

Faeces (random sample)

Protect samples from light

Volume

2 ml (blood); 10 ml (urine); 10 g (faeces)

Container

Vacutainer lemon top

Vacutainer green top

Porphy

Urine bottle white top

Collection

Samples should be transported to the laboratory protected from light (wrap in black plastic or put into thick brown envelope)

Causes for Rejection

Unlabelled sample

Interpretation

See laboratory report for interpretation

In acute neurological attacks: if urine screen normal and urine was collected during a suspected attack then no further tests are normally required.