CD-ROM Today (UK) (Spanish) 15/CDRT.iso/dp/0412/04125.txt

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$Unique_ID{BRK04125}
$Pretitle{}
$Title{Porphyria}
$Subject{Porphyria Acute Intermittent Porphyria Variegate Porphyria Hereditary
Coproporphyria Protoporphyria Porphyria Cutanea Tarda Congenital
Erythropoietic Porphyria ALA-D Porphyria}
$Volume{}
$Log{}

Copyright (C) 1990, 1991, 1992 National Organization for Rare Disorders,
Inc.

675:
Porphyria

** IMPORTANT **
It is possible the main title of the article (Porphyria) is not the name
you expected.  Please check the SYNONYMS listing on the next page to find
alternate names and disorder subdivisions covered by this article.

Synonyms

Disorder Subdivisions:

     Acute Intermittent Porphyria
     Variegate Porphyria
     Hereditary Coproporphyria
     Protoporphyria
     Porphyria Cutanea Tarda
     Congenital Erythropoietic Porphyria
     ALA-D Porphyria

General Discussion

** REMINDER **

The information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.


Porphyria is not one, but at least seven types of rare and complex
disorders.  The different types vary in their clinical presentation.
Basically the clinical problems group themselves into disorders of the
nervous system and skin.  Sometimes these symptoms are so ill-defined that
proper diagnosis is delayed.  The urine of some patients is a purple-red
color or changes to that color when exposed to light.

ACUTE INTERMITTENT PORPHYRIA
Abdominal pain is the most common complaint in Acute Intermittent
Porphyria.  In addition, some of the following symptoms occur with varying
frequency:  pain in the arms and leg, generalized weakness, vomiting,
confusion, constipation, tachycardia, fluctuating blood pressure, urinary
retention, psychosis, hallucinations, and seizures.  The muscle weakness may
progress to respiratory paralysis, necessitating artificial respiration.
Porphobilinogen is elevated during the attack but may be consistently high in
some patients.  urine may exhibit a purple-red color.  Unlike other forms of
porphyria, sun sensitivity is not present in this type.

VARIEGATE PORPHYRIA
Variegate Porphyria is characterized by abrasions, blisters, and erosions
of the skin which are commonly seen during the second and third decade.
These lesions tend to heal slowly, often leaving pigmented or slightly
depressed scars.  The patients experience sensitivity to light and fragility
of skin exposed to the sun.  Although in many patients manifestations remain
limited to the skin, episodes similar to those of acute porphyria are not
uncommon.  Therefore, the symptoms, drugs, precautionary measures, and
treatment described for Acute intermittent porphyria are applicable to
variegate porphyria.  (See the Standard Therapy section.

HEREDITARY COPROPORPHYRIA
The large amounts of coproporphyrin present in Hereditary Coproporphyrin
makes the patient sensitive to sunlight, but skin disease is rarely severe in
this type of porphyria.  Clinically it resembles Variegate Porphyria except
that a larger percentage of affected individuals exhibit few symptoms.  Other
symptoms are similar to those listed for Acute Intermittent Porphyria.

PROTOPORPHYRIA

Protoporphyria can have mild to severe light sensitivity and burning on
exposure to the sunlight.  Usually, the symptoms subside in twelve to twenty-
four hours and heal without significant scarring or discoloration to the
skin.  The skin lesions may also progress to a chronic stage persisting for
weeks and healing with a superficial scar.  These manifestations generally
begin in childhood.  They are more severe in the summer and can recur
throughout life.  Affected skin, at times, exhibits the fragility or blister
formation seen in other photosensitizing types of porphyria.  Hepatobiliary
dysfunction may be associated with significant liver damage.

PORPHYRIA CUTANEA TARDA
In Porphyria Cutanea Tarda, exposed skin shows abnormalities similar to
those found in variegate porphyria.  They range from slight fragility of the
skin to persistent scarring and disfiguration.  Due to fragility of the skin,
minor trauma may induce blister formation.  Areas of increased and decreased
pigment content may be noted on the skin.  Blistering of light exposed skin
and increased hair growth, especially on the face, are also characteristic.

CONGENITAL ERYTHROPOIETIC PORPHYRIA
This is a very rare disease with approximately 150 patients reported in
the world.  Congenital Erythropoietic Porphyria is often manifested shortly
after birth with dark urine and sunlight sensitivity causing blistering and
skin fragility.  Later, brownish, fluorescent teeth, increased hair growth,
and pronounced scarring may occur.  In some cases, loss of fingers and toes
and cartilage from ears or nose may be noted.

ALA-D PORPHYRIA
ALA-D Porphyria symptoms usually arise from effects on the nervous system
and/or the skin.  Sometimes, the cause of the nervous system symptoms is not
clear.  Skin manifestations include burning, blistering, and scarring of the
sun exposed areas.  The disease usually manifests after puberty, and more
commonly occurs in women.  The most common symptom is severe abdominal pain.
Other characteristics are nausea, vomiting, rapid heart rate, increased blood
pressure, confusion and/or seizures, and the passing of ALA (delta-
aminolevulinic acid) in the urine.

For more complete information on each of the individual types of
Porphyria, choose "Porphyria" as your search term in the Rare Disease
Database.)

Causes

The porphyrias are most often inherited.  There is a unique enzyme deficiency
in each type of the disease.  These enzymes are involved in the synthesis of
heme, the oxygen carrying part of hemoglobin in red blood cells.  Virtually
all cases or porphyria have a dominant inheritance.  (Human traits including
the classic genetic diseases, are the product of the interaction of two genes
for that condition, one received from the father and one from the mother.  In
dominant disorders, a single copy of the disease gene (received from either
the mother or father) will be expressed "dominating" the normal gene and
resulting in appearance of the disease.  The risk of transmitting the
disorder from affected parent to offspring is 50% for each pregnancy
regardless of the sex of the resulting child.)

Therapies:  Standard

The basic defect cannot presently be treated, but significant effort is being
directed toward treating the underlying mechanisms that cause symptoms.

Drugs which are considered harmful for persons with Acute Intermittent
Porphyria, Varigeta Porphyria, and Hereditary Coproporphyria include:

     1.  Barbiturates
     2.  Sulfonamides
     3.  Other tranquilizers and sedatives
     4.  Griseofulvin
     5.  Anti-epilepsy drugs.
     6.  Birth control pills

The orphan drug Hemin 2,3, is approved for use as a treatment for various
forms of Porphyria.  It is manufactured by Abbott Labs.

Therapies:  Investigational

Dr. Karl Anderson of Texas Medical Branch, Galveston, TX, 77550, has received
orphan drug designation for Histrelin, a drug to treat various types of
Porphyria.

Leiras, manufacturer of the drug heme arginate for treatment of
Porphyria, has agreed to supply the United States with the drug for studies
here.  Heme Arginate may prove to be a safer product for treatment of acute
prophyrias as there are fewer side effects.  Leiras is the pharmaceutical
division of the Finish company Huhtamaki Corp.  For more information, please
contact:

     Ms. Pirjo Pietilainen
     Leiras
     P.O. Box 415
     SF-20101 Turku
     Finland

This disease entry is based upon medical information available through
July 1992.  Since NORD's resources are limited, it is not possible to keep
every entry in the Rare Disease Database completely current and accurate.
Please check with the agencies listed in the Resources section for the most
current information about this disorder.

Resources

For more information on Porphyria, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     American Porphyria Foundation
     P.O. Box 22712
     Houston, TX  77227
     [phone]

     National Digestive Diseases Information Clearinghouse
     Box NDDIC
     Bethesda, MD  20892
     [phone]

For genetic information and genetic counseling referrals, please contact:

     March of Dimes Birth Defects Foundation
     1275 Mamaroneck Avenue
     White Plains, NY  10605
     [phone]

     Alliance of Genetic Support Groups
     35 Wisconsin Circle, Suite 440
     Chevy Chase, MD  20815
     (800) 336-GENE
     [phone]

References

American Porphyria Foundation Brochure, "Common Questions Asked About
Porphyria."