Ordering Recommendation

Evaluate patients with suspected porphyria presenting with neurologic/psychiatric, abdominal, and/or cutaneous symptoms.

New York DOH Approval Status

Testing is not New York state approved. Specimens from New York clients will be sent out to a New York state-approved laboratory.

Specimen Required

Patient Preparation
Collect

24-hour or random urine. Refrigerate 24-hour specimens during collection.

Specimen Preparation

Protect from light. Transfer 8 mL aliquot to an ARUP amber transport tube. (Min: 4 mL) Record total volume and collection time interval on transport tube and test request form.

Storage/Transport Temperature

Frozen.

Unacceptable Conditions

Body fluids other than urine.

Remarks
Stability

Ambient: Unacceptable; Refrigerated: 4 days; Frozen: 1 month

Methodology

Quantitative High Performance Liquid Chromatography (HPLC)/Quantitative Spectrophotometry/Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry

Performed

Sun-Sat

Reported

2-5 days

Reference Interval

Test Number
Components
Reference Interval
  Creatinine, Urine - per 24h
Age
Male (mg/d)
Female (mg/d)
3-8 years 140-700 140-700
9-12 years 300-1300 300-1300
13-17 years 500-2300 400-1600
18-50 years 1000-2500 700-1600
51-80 years 800-2100 500-1400
81 years and older 600-2000 400-1300

  Porphobilinogen, Urine - ratio to CRT 0.0 - 0.2 mmol/mol CRT
  Uroporphyrin - ratio to CRT 0-4 µmol/mol CRT
  Heptacarboxylate - ratio to CRT 0-2 µmol/mol CRT
  Porphobilinogen (PBG), Urine -per 24h 0.4 - 1.5 µmol/d
  Coproporphyrin I - ratio to CRT 0-6 µmol/mol CRT
  Coproporphyrin III - ratio to CRT 0-14 µmol/mol CRT

Interpretive Data

Results are normalized to creatinine concentration and reported as a ratio of amounts (micromoles of porphyrin/moles of creatinine).

Porphobilinogen (PBG), Urine

Results for random urine specimens are normalized to creatinine (CRT) concentration and reported as a ratio of amounts (millimoles of PBG/mole of creatinine).

Porphobilinogen (PBG) in a random urine specimen is used to evaluate an attack of acute porphyria. Slight increases in urinary PBG are associated with acute porphyrias other than acute intermittent porphyria (AIP) and may indicate a resolving or treated acute porphyria.

Urinary PBG in excess of two times the upper reference limit is consistent with acute porphyria.

Per 24h calculations are provided to aid interpretation for collections with a duration of 24 hours and an average daily urine volume. For specimens with notable deviations in collection time or volume, ratios of analytes to a corresponding urine creatinine concentration may assist in result interpretation.

Compliance Category

Laboratory Developed Test (LDT)

Note

Urine porphyrins are useful for the evaluation of cutaneous photosensitivity to exclude porphyria cutanea tarda (PCT). Urine porphobilinogen (PBG) is useful for the evaluation of neurologic and/or psychiatric symptoms to exclude acute porphyrias such as acute intermittent porphyria (AIP).

Hotline History

N/A

CPT Codes

84120; 84110

Components

Component Test Code* Component Chart Name LOINC
0020207 Creatinine, Urine - per volume 2161-8
0020208 Creatinine, Urine - per 24h 2162-6
0080262 Porphobilinogen (PBG), Urine -per volume 2811-8
0080365 Uroporphyrin - ratio to CRT 32043-2
0080366 Heptacarboxylate - ratio to CRT 38175-6
0080369 Porphobilinogen (PBG), Urine -per 24h 14882-5
0080459 Porphyrin Urine Interpretation 49292-6
0097110 Total Volume 19153-6
0097111 Hours Collected 30211-7
2002059 Coproporphyrin I - ratio to CRT 45313-4
2002061 Coproporphyrin III - ratio to CRT 45315-9
3017599 Porphobilinogen, Urine - ratio to CRT
3017600 Porphobilinogen Interpretation
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • Coproporphyrin
  • Heptacarboxyl Porphyrin
  • Hexacarboxyl Porphyrin
  • PBG
  • Pentacarboxyl Porphyrin
  • Porphobilinogen
  • Porphyrins, Quantitative, 24-Hour Urine
  • Urine Quantitative
  • Uroporphyrin
Porphyrins and Porphobilinogen (PBG), Urine