75025-7

Coproporphyrin 3/Porphyrins.total in Stool

Active

Term Description

Total fecal porphyrins are markedly increased especially in active HCP (Hereditary Coproporphyria) and VP (Variegate Porphyria) and to a lesser extent in PCT (Porphyria Cutanea Tarda) and EPP (Erythropoietic Protoporphyria). Fecal porphyrins can be separated and measured individually by HPLC. Porphyrins with 2-4 carboxyl groups generally predominate in feces. These are excreted by the liver into the bile and then flow into the intestine. As with urine, it is most useful to measure the total amount of porphyrins in a fecal sample. If this is increased, then the laboratory should determine which porphyrins predominate rather than focus on the amount of each porphyrin. Fecal porphyrin determinations may be confounded by variations in fecal flow; most people have one or a few bowel movements daily and a "24 hour stool collection" is really not uniform from day to day. Substances in the diet and any internal bleeding into the stomach or intestines may also interfere.

Part Description

LP14372-4   Coproporphyrin 3
Coproporhyrin III is a porphyrin metabolite arising from heme synthesis. Porphyrins are pigments found in both animal and plant life. Coproporphyrin III is a tetrapyrrole dead-end product from the spontaneous oxidation of the methylene bridges of coproporphynogen, arising from heme synthesis and secreted in feces and urine. Increased levels of coproporphyrins can indicate congenital erythropoietic porphyria or sideroblastic anaemia. Porphyria is a pathological state characterised by abnormalities of porphyrin metabolism and results in the excretion of large quantities of porphyrins in the urine and in extreme sensitivity to light. A large number of factors are capable of increasing porphyrin excretion, owing to different and multiple causes and etiologies: 1) the main site of the chronic hepatic porphyria disease process concentrates on the liver, 2) a functional and morphologic liver injury is almost regularly associated with this chronic porphyria, 3) the toxic form due to occupational and environmental exposure takes mainly a subclinical course. Hepatic factors includes disturbance in coproporphyrinogen metabolism, which results from inhibition of coproporphyrinogen oxidase as well as from the rapid loss from, and diminished utilization of coproporphyrinogen in the hepatocytes, which may also explain why coproporphyrin, its autoxidation product, predominates physiologically in the urine; decreased biliary excretion of coproporphyrin leading to a compensatory urinary excretion, so that the coproporphyrin ring isomer ratio (1:III) becomes a sensitive index for impaired liver function and intrahepatic cholestasis; and disturbed activity of hepatic uroporphyrinogen decarboxylase. In itself, secondary coproporphyrinuria is not associated with porphyria symptoms of a hepatologic-gastroenterologic, neurologic, or dermatologic order, even though coproporphyrinuria can occur with such symptoms. PMID: 3327428 Copyright Copyright ©2005-2009 Genome Alberta (Reference to original publication: Wishart DS, Knox C, Guo AC, et al. HMDB: a knowledgebase for the human metabolome. Nucleic Acids Res. 2009 37(Database issue):D603-610.) Source: Human Metabolome Database , Corproporphyrin III

Fully-Specified Name

Component

Coproporphyrin 3/Porphyrins.total

Property

SFr

Time

Pt

System

Stool

Scale

Qn

Method

Additional Names

Long Common Name

Coproporphyrin 3/Porphyrins.total in Stool

Short Name

Copro3 SFr Stl

Display Name

Coproporphyrin 3/Total porphyrins (Stl) [Molar fraction]

Consumer Name Alpha Get Info

Coproporphyrin 3/Total Porphyrins, Stool

Basic Attributes

Class

CHEM

Type

Laboratory

First Released

Version 2.48

Last Updated

Version 2.48 (MIN)

Order vs. Observation

Both

Member of these Panels

Language Variants Get Info

Related Names

• Bowel movement
• Chemistry
• Copro
• Copro3
• Coproporph
• Coproporphyrin III
• Coproporphyrins
• Faecal
• Faeces
• Fecal
• Feces
• Hematology
• Heme
• III
• Percent
• Point in time
• Porph
• Porphyrin
• QNT
• Quan
• Quant
• Quantitative
• Random
• Stl
• Stool = Fecal
• Substance Fraction
• Tetracarboxyl porphyrin
• Tetracarboxylporphyrin
• Tetracarboxylporphyrins
• Tetracarboxyporphyrin
• Tot
• Totl

Example Units

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