Porphyrins, Stool (Sendout)

Useful For: Evaluation of patients who present with signs or symptoms suggestive of porphyria cutanea tarda, hereditary coproporphyria, variegate porphyria, congenital erythropoietic porphyria, erythropoietic protoporphyria, or X-linked dominant protoporphyria.

Patient Preparation:

• Patient should refrain from eating red meat and taking aspirin-containing medications for 3 days prior to, as well as during, specimen collection. Compliance should be indicated.
• No barium, laxatives, or enemas may be used within 24 hours of starting, or during, the collection.

Ordering Requirements: Include a list of medications that the patient is currently taking in the Epic order comments.

Cautions:

Heme from red meat can contribute to fecal protoporphyrin concentrations and cause a misleading indication of erythropoietic protoporphyria, X-linked dominant protoporphyria, or variegate porphyria.

Aspirin ingestion may cause minimal gastrointestinal bleeding, leading to false elevations of protoporphyrin.

Specimen submitted should contain at least 100 g of feces. Specimens smaller than 100 g may not provide interpretable results. Specimens weighing less than 10 grams will be rejected.

Timed Stool Specimen (48, 72, or 96 hour): Collect stool in Mayo preservative-free Mayo collection container(s) (Mayo Supply T291) for the requested time period indicated by the ordering provider.

• Also Acceptable: 24-Hour collection is adequate if the collection volume is approximately 100 g.
• Patients should label all containers (1 of 3, 2 of 3, etc.) during collection and record the total collection interval.

UW Medicine Patients may obtain Mayo Collection Kits at:

• HMC Laboratory (Harborview Medical Center, Room GWH-47)
• UW-MT laboratory (University of Washingtong Montlake, Room NW-220)
• Mayo generally recommends one kit (includes 2 containers) per 24 hours of collection.
  • 24-Hr: 1 kit; 48-Hr: 2 kits; 72-Hr: 3 kits; 96-Hr: 4 kits

Random Collection: Collect a minimum of 100 g stool in a preservative-free stool collection container.

Outside Clients:

• For timed collections, obtain preservative-free collection containers from Client Support Services (Mayo supply T291).
• Instruct the patient to label all containers (1 of 3, 2 of 3, etc.) during collection and record the total collection interval.
• Freeze samples at -20°C upon completion.
• On the DLMP Requisition, indicate:
  • Duration of collection.
  • Weight of the non-homogenized sample.
  • List of medications that the patient is currently taking.
• Transport samples on dry ice.

Stability: Frozen (preferred): 14 days; Refrigerated: 14 days; Ambient: Unacceptable.

Reject Due To: Specimens in preservative. Specimens smaller than 100 g may not provide interpretable results.

Freeze specimen(s) at -20°C. Write the collection duration on the requisition and make a copy for Sendouts.

Sendouts:

• Order Mayo Test: FQPPS.
• Interfaced: No.
• Enter the collection duration in the MayoAccess order. If a list of medications was included in the Epic order comments, include them under 'Non-Chartable Comments.'

Stability: Frozen (preferred): 14 days; Refrigerated: 14 days; Ambient: Unacceptable.

Reject Due To: Specimens in preservative. Specimens smaller than 100 g may not provide interpretable results.