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PORPHYRIA FACTS: TESTING
EHRLICH’S ALDEHYDE
Ehrlich’s aldehyde test
Urinary porphobilinogen test
Ehrlich's aldehyde test is used to confirm a diagnosis of acute intermittent
porphyria.
Ehlich's aldehyde reagent consists of p-dimethyl amino benzaldehyde in acid
solution.
Equal volumes of urine and Ehrlich's reagent are mixed. If a pink colour is
formed this indicates a raised urinary concentration of either porphobilinogen or
urobilinogen.
In cases of raised porphobilinogen, as in acute intermittent porphyria, the pink
precipitate is observed to be insoluble in chloroform.
SOURCE:
The University of Minnesota
Watson-Schwartz Laboratory
Minneapolis, MN.
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TESTING WATSON - SCHWARTZ
In obtaining a porphyria diagnosis the Watson-Schwartz test for excessive
amounts of urinary porphobilinogen still widely used in emergencies is favored
for its easy execution with just a few test tubes and some reagents, must always
lead to further detailed studies.
A newer test, although slightly more complicated, is more sensitive.
SOURCE:
Porphyria Conundrum
Claus A. Pierach
Cecil Watson Laboratory
University of Minnesota
Abbott Northwestern Hospital
Minneapolis, MN 55407-3799
Clinical Chemistry.
1999;45:932-933.
American Association for Clinical Chemistry, Inc.
++++++++++
A comparison of the Hoesch and the Watson-Schwartz tests shows that the
latter, although slightly more complicated, generally yields more concise results
and is superior in sensitivity and specificity for porphobilinogen.
The recommendation of the Hoesch test for use as a "bedside screening"
method seems unrealistic.
SOURCE:
Clinical Chemistry
1977 Sep;23(9):1666-8.
Comparison of the Hoesch and the Watson-Schwartz tests for urinary
porphobilinogen.
Pierach CA, Cardinal R, Bossenmaier I, Watson CJ.Clinical Chemistry
1977 Sep;23(9):1666-8.
+++++++++++
The Watson-Schwartz Test is the porphyria "bedside test" of choice.
SOURCE:
Clinical Chemistry
1977 Sep;23(9):1666-8.
Comparison of the Hoesch and the Watson-Schwartz tests for urinary
porphobilinogen.
Pierach CA, Cardinal R, Bossenmaier I, Watson CJ.Clinical Chemistry
1977 Sep;23(9):1666-8.
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TESTING - BLOOD PORPHYRIN TESTING
Blooding testing in porphyria is not just one test.
There are several various red blood cells testswhich measure different aspects.
Descriptions of each are below.
Unlike urine testing blood serum testing in porphyria can be undertaken at any
time as the blood porphyrin level remains constant whether in attack or in
remission.
SOURCE
Robert Johnson MD
Internal Medicine
++++++++++++++++++
In contrast to plasma porphyrins, no other tests detects all cutaneous
porphyrias.
SOURCE:
Primer on Laboratory Testing for Porphyrias
Dr. Karl E. Anderson
Porphyria Laboratory
University of Texas Medical Branch
Galveston, TX
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Measurement of porphobilinogen in serum is useful when acute
porphyria is suspected and urine cannot be collected.
SOURCE:
Primer on Laboratory Testing for Porphyrias
Dr. Karl E. Anderson
Porphyria Laboratory
University of Texas Medical Branch
++++++++++++++++++
Heme enzyme assays are useful for family studies, when it is established that an
index case has a particular enzyme deficiency .
SOURCE:
Primer on Laboratory Testing for Porphyrias
Dr. Karl E. Anderson
Porphyria Laboratory
University of Texas Medical Branch
Galveston, TX
+++++++++++++++++++++
PORPHYRIN TYPES FOUND IN BLOOD TESTING
What are the types of porphyrins that can be measured in the porphyrin red
blood cell test?
Coproporphyrin, protoporphyrin, and uroporphyrin are three porphyrins
related to red blood cells that can normally be measured in small amount in
the human blood stream.
SOURCE:
Prodigy Porphyria Resource
1999 A.D.A.M Internet Health Inc.
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PORPHYRIN DETECTION IN RED BLOOD CELLS
Can porphyria be detected in RBCs?
The definitive test is to measure monopyrrole porphobilinogen deaminase
in RBCs.
SOURCE:
Porphyria: reexamination of psychiatric implications.
Burgovne K, Swartz R, Ananth J.
Harbor-UCLA Medical Center, Torrance 90509, USA.
Psychother Psychosom 1995;64(3-4):121-30
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DEFINITIVE PORPHYRIA TEST FOR AIP TYPE I
What is the definitive test for AIP Type I?
The definitive test for AIP Type I is to measure monopyrrole porphobilinogen
deaminase in RBCs.
This test however will remain negative for AIP Type II which must be measured
in urine and/or liver biopsy.
SOURCE:
Porphyria
Burgoyne, K., R. Swartz, et al.
Psychotherapy & Psychosomedicine
1995; 64(3-4): 121-30.
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NO DEFINITIVE BLOOD TEST FOR HCP
Is there a blood enzyme test for the diagnosis of HCP?
No enzyme test is currently available to measure the activity of
coproporphyrinogen oxidase.
SOURCE:
Lister Hill National Center for
Biomedical Communications
National Institutes of Health
Department of Health & Human Services
+++++++++++++++
When should the special porphyria laboratories be used and contact made with
a testing porphyria specialist?
In specialized testing, a physician and laboratory with experience in
testing for porphyrias and in theclinical management of these disorders should
be consulted.
SOURCE:
Primer on Laboratory Testing for Porphyrias
Dr. Karl E. Anderson
Porphyria Laboratory
University of Texas Medical Branch
Galveston, TX
++++++++++++++++++++++
Do all AIP patients have a 50% diminished level of PBG-deaminase
in their blood?
A subgroup of patients with AIP have normal PBG deaminase activity in
erythrocytes, although the activity of the hepatic enzyme is decreased.
SOURCE:
Acute Intermittent Porphyria
Scheiber, William E. et. al.
American Jornal of Clinical Pathology
Vol. 103 No. 6
June 1995
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Do all AIP patients have to have a diminished level of PBG-D in their blood
serium?
In one study of 385 acute intermittent porphyria patients 5% had normal
porphobilinogen deaminase activity.
SOURCE:
Heterogeneity of acute intermittent porphyria: a
subtype with normal erythrocyte porphobilinogen
deaminase activity
Gross U, Honcamp M, Doss MO.
Abteilung fur Klinische Biochemie
Klinikum der Philipps-University
Marburg, Germany
European ournal of Clinical Chemistry & Clinical Biochemistry
1996 Aug;34(8):613-8
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PORPHYRINS - red cell
Specimen: 5 mL blood in heparinised tube, protected from light and
transported rapidly to the laboratory.
Method: Spectrophotometry or fluorometry.
Reference Interval: <900 nmol/L red cells.
Application: Detection of congenital erythropoietic porphyria (EP), which is
very rare, and protoporphyria (PP) in childhood.
The test may be indicated in adults with skin photosensitivity not due to
porphyria variegata or porphyria cutanea tarda, if mild EP or PP require
exclusion.
Interpretation: Erythrocyte protoporphyrin is raised in PP.
It is also raised in lead exposure and may be useful in the assessment of lead
intoxication.
It is slightly elevated in iron deficiency but should not be used for the diagnosis
of this condition.
SOURCE:
Porphyria
Kushner JP.
New EnglandJournal of Medicine
1991; 324: 1432-1434
++++++++++++++++++
Hemolysis of a blood sample invalidates a plasma porphyrin determination
because normal erythrocytes contain much larger amounts of porphyrin (in the
form of Zn protoporphyrin) than does normal plasma.
SOURCE:
Primer on Laboratory Testing for Porphyrias
Dr. Karl E. Anderson
Porphyria Laboratory
University of Texas Medical Branch
++++++++++++++++++++
PORPHOBILINOGEN SYNTHETASE - red cell
Specimen: 2 mL blood in lithium heparin tube.
Method: Spectrophotometry.
Reference Interval: Varies with method: generally 10-26 U/L.
Application: Decrease in the enzyme has been used as an indicator of
increased lead exposure, but this has been largely superseded by measurement
of blood lead.
The enzyme is also decreased in the very rare genetic disease,
plumboporphyria.
Interpretation: Inhibition of the enzyme commences with levels of blood lead
unlikely to cause acute symptoms.
Plumboporphyria is an autosomal recessive disease with virtual absence of
enzyme activity; heterozygotes have about 50% activity.
SOURCE:
The Porphyrias
Thunell S.
Journal of Clinical Chemistry &
Clinical Biochemistry
1987; 25: 5-14.
Porphyrins, blood
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Are red blood cell indices testing used in porphyria patients?
When anemia is found such testing is performed.
Also bed blood cell indices are performed on hepatic porphyria patients.
SOURCE:
Guide ot Medical Tests
Pinckney, Cathey et. al.
3rd Edition
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PROTOCOL FOR PORPHYRIN BLOOD TESTING
Blood is drawn from a vein (venipuncture), usually from the inside of
the elbow or the back of the hand.
The puncture site is cleaned with antiseptic, and a tourniquet (an elastic band)
or blood pressure cuff is placed around the upper arm to apply pressure and
restrict blood flow through the vein.
This causes veins below the tourniquet to distend (fill with blood).
A needle is inserted into the vein, and the blood is collected in an air-tight vial or
a syringe.
During the procedure, the tourniquet is removed to restore circulation.
Once the blood has been collected, the needle is removed, and the puncture
site is covered to stop any bleeding.
The sample is then placed in ice and taken immediately to the laboratory.
This test is used to diagnose porphyrin disorders involving red blood
cells.
Special Considerations
Failure to comply with dietary restrictions prior to the test may alter
and invalidate test results.***
How to prepare for the test.
*****Fasting for 12 to 14 hours prior to this test is required.
You may drink water right before the test.
SOURCE: Prodigy Porphyria Resource
1999 A.D.A.M Internet Health Inc.
RED BLOOD CELL PORPHYRIN TEST
Definition
This test measures total red blood cell porphyrins.
Porphyrins are pigments found in both animal and plant life.
Coproporphyrin,protoporphyrin, anduroporphyrin are three porphyrinsrelated to
red blood cells that can normally be measured in smallamount in the human
blood stream.
Protoporphyrin is normally found in highest quantity and thus thistest is
occasionally known as the PROTO test.
Additional tests must be performed to know the levels of specific porphyrins.
Alternative Names for this test include:
uroporphyrin levels; protoporphyrin levels; porphyrins, total; coproporphyrin
levels
How the test is performed
Blood is drawn from a vein during a venipuncture procedure.
The sample is then placed in ice and taken immediately to the laboratory.
Normal values
This test specifically measures total porphyrin levels, but reference values
for the individual components are also included:
total porphyrin levels: 16 to 60 mcg/dl
coproporphyrin levels: < 2 mcg/dl
protoporphyrin levels: 16 to 60 mcg/dl
uroporphyrin levels: < 2 mcg/dl
Note: mcg/dl = micrograms per deciliter
Special Considerations
Failure to comply with dietary restrictions prior to the test may alter and
invalidate test results.
What abnormal results mean in red blood testing.
Increased levels of coproporphyrins may indicate:
congenital erythropoietic porphyria
sideroblastic anemia
Increased protoporphyrin levels may indicate:
infection
thalassemia
sideroblastic anemia
lead poisoning
iron deficiency anemia
erythropoietic anemia
increased erythropoiesis
Increased uroporphyrin levels may indicate:
congenital erythropoietic porphyria
erythropoietic protoporphyria
How to prepare for the test
Fasting for 12 to 14 hours prior to this test is required. You may drink water right
before the test.
If your child is to have this test performed it may be helpful to explain how the
test will feel, and evenmpractice or demonstrate on a doll.
The more familiar your child is with what will happen to them, and the
purpose for the procedure, the less anxiety they will feel.
SOURCE
*Used with permision.
United Hospital Laboratory Services
1996
++++++++++++++++++
Erythrocyte count; Red blood cell count
The Erthrocyte count is a blood test that measures the number of red blood cells
(RBCs).
The RBC count is almost always ordered as part of the complete blood count
(CBC) test.
RBCs transport hemoglobin which, in turn, transports oxygen. The amount of
oxygen received by tissue is dependent on the amount and function of RBCs
and hemoglobin.
RBCs normally survive for about 120 days in the blood; they are then removed
by phagocytic cells in the spleen or Kupffer cells in the liver.
SOURCE:
Rebecca Elstrom, M.D.,
Division of Hematology-Oncology,
University of Pennsylvania Medical Center,
Philadelphia, PA.
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Blood sedimentation test.
A test that measures the speed at which red blood cells settle at the bottom of a
column of blood in a glass tube.
The rate (speed) depends on the amount of certain proteins in the blood.
Elevated levels may indicate some types of inflammatory or infectious disorders.
Also called erythrocyte sedimentation rate or sed rate.
SOURCE:
Mayo Medical Education
Mayo Foundation
Rochester, MN
+++++++ ++++
This test measures total red blood cell porphyrins.
Porphyrins are pigments found in both animal and plant life.
They are involved in the formation of many important substances in the body
including hemoglobin which carries oxygen in the blood.
Coproporphyrin, protoporphyrin, and uroporphyrin are three porphyrins related
to red blood cells that can normally be measured in small amount in the human
blood stream.
Protoporphyrin is normally found in highest quantity and thus this test is
occasionally known as the PROTO test.
Additional tests must be performed to know the levels
: TESTING - URINE PORPHYRIN
When urine porphyrins are abnormal, characterization of the chromatogram is
facilitated by calculation of uroporphyrin-to-heptacarboxylate porphyrin
(uro/hepta) and (uro/iso) ratios.
SOURCE:
K. Nutall M.D.
Annals of Clinical Laboratory Science
2001 Jul;31(3):259-64
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Delta-ALA Urine Test (delta-aminolevulinic acid)
A test that measures the amount of delta-ALA in urine.
A 24-hour urine sample is needed.
The health care provider will instruct you, if necessary, to discontinue drugs that
may interfere with the test.
Drugs that may increase test measurements include penicillin, barbiturates, oral
contraceptives, and griseofulvin.
On day 1, urinate into the toilet upon arising in the morning.
Collect all subsequent urine (in a special container) for the next 24-hours.
On day 2, urinate into the container in the morning upon arising.
Cap the container. Keep it in the refrigerator or a cool place during the collection
period. Label the container with your name, the date, the time of completion, and
return it as instructed.
Deliver it to the laboratory or your health care provider as soon as possible upon
completion.
Avoid exposure of the urine to direct light.
Keep the sample refrigerated.
This test is useful in detecting specific liver abnormalities.
1 to 7 mg per 24-hours are normal values.
Note: mg = milligrams
Increased levels of urinary delta-ALA may indicate:
lead poisoning
porphyria (several types)
Decreased levels may occur with chronic liver disease.
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PBG (porphobilinogen ) urine test
A test that measures the amount of PBG in urine.
A 24-hour urine sample is needed.
The health care provider will instruct you, if necessary, to discontinue drugs that
may interfere with the test.
Drugs that can affect test measurements include aminosalicylic acid,
barbiturates, chloral hydrate, chlorpropamide, ethyl alcohol, griseofulvin,
morphine, oral contraceptives, phenazopyridine, procaine, and sulfonamides.
On day 1, urinate into the toilet upon arising in the morning.
Collect all subsequent urine (in a special container) for the next 24-hours.
On day 2, urinate into the container in the morning upon arising.
Cap the container. Keep it in the refrigerator or a cool place during the collection
period. Label the container with your name, the date, the time of completion, and
return it as instructed.
Deliver it to the laboratory or your health care provider as soon as possible upon
completion.
This test may be performed when porphyria or another disorder associated with
abnormal PBG level is suspected.
Normal values in PBG testing are:
random urine: negative test
24-hour urine: 1.5 to 2 mg (milligrams) per 24-hours
Increased levels of urinary PBG may indicate:
hepatic carcinoma (liver cancer)
hepatitis
lead poisoning
porphyria (several types)
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Uroporphyrin Testing
This is a test that measures the level of porphyrins in urine.
A 24-hour urine sample is needed.
The health care provider will instruct you, if necessary, to discontinue drugs that
may interfere with the test.
Drugs that can affect test measurements include aminosalicylic acid,
barbiturates, chloral hydrate, chlorpropamide, ethyl alcohol, griseofulvin,
morphine, oral contraceptives, phenazopyridine, procaine, and sulfonamides.
On day 1, urinate into the toilet upon arising in the morning.
Collect all subsequent urine (in a special container) for the next 24-hours.
On day 2, urinate into the container in the morning upon arising.
Cap the container. Keep it in the refrigerator or a cool place during the collection
period. Label the container with your name, the date, the time of completion, and
return it as instructed.
Deliver it to the laboratory or your health care provider as soon as possible upon
completion.
This test is most often performed when porphyria or other disorders that can
cause abnormal urine porphyrins is suspected.
Random urine: negative test
24-hour urine: 50 to 300 mg per 24-hours
Note: mg = milligrams
Increased levels of urinary PBG may indicate:
Hepatic carcinoma (liver cancer)
Hepatitis
Lead poisoning
Porphyria (several types)
Levels of ALA, uroporphyrin, and coproporphyrin may also be raised in specific
types of porphyria.
SOURCE:
Rebecca Elstrom, M.D.
Division of Hematology-Oncology
University of Pennsylvania Medical Center
Philadelphia, PA.
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LIVER ENZYME TESTING
Liver enzyme testing does not typically fall within the realm of routine diagnostic
testing.
However, testing for these levels is indicated if liver or biliary tract disease is in
the differential diagnosis list.
Four liver enzymes should be monitored as markers of liver or biliary tract
disease: alanine aminotransferase (ALT), aspartate aminotransferase (AST),
alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (GGT).
Alanine aminotransferase and aspartate aminotransferase are indicators of liver
cell damage.
Alkaline phosphatase and gamma-glutamyl transpeptidase are indicators of
biliary system obstruction.
Fasting is not required for liver enzyme function tests. Other liver function tests
(serum albumin, prothrombin time and bilirubin) or hepatitis panels may be
ordered when you suspect hepatobiliary disease.
Liver Cell Damage
Alanine aminotransferase (formerly serum glutamic-pyruvic transaminase or
SGPT) is very specific for liver malfunction because high concentrations of this
enzyme occur in the liver.
The ALT is especially useful in determining hepatic cirrhosis and viral hepatitis.
If testing shows elevations in the ALT, follow up with a hepatitis panel.
Aspartate aminotransferase (formerly SGOT) occurs primarily in the liver, heart,
skeletal muscles, kidneys and pancreas.
Elevations of this enzyme indicate cellular damage but the readings are not
specific for the liver.
For example, in the presence of myocardial infarction, the AST will peak within
24 hours and return to normal within 3 to 7 days.
Shock, muscle disease, extreme exercise and renal disease can also cause
elevations.
Biliary Tract Obstruction
Alkaline phospatase is very sensitive to mild biliary obstruction and is a primary
indicator of space-occupying hepatic lesions.
Also, since ALP is an indicator of metabolic bone disease, additional liver
function studies are usually required to identify hepatobiliary disorders.
Numerous acute hepatic diseases cause ALP elevations before they result in
any change in serum bilirubin levels.
Gamma-glutamyl transpeptidase is more sensitive to biliary obstruction than
AST and ALP.
The GGT is also useful in diagnosing cancer of the liver or pancreas. Another
use for the GGT is to screen for the consequences of chronic alcoholism.
The table accompanying this article outlines normal and abnormal liver enzyme
findings and what the results suggest.
Liver Enzyme Results and Corresponding Indications
Liver Enzyme
Normal
Result
Abnormal
Result
Indications
Alanine
Aminotransferase
7-24 U/L
50 x Normal
Viral or severe drug-induced hepatitis
Moderate
Mononucleosis, chronic hepatitis,
cholesystitis, hepatic congestion
Slight to
moderate
Acute liver injury—active cirrhosis,
drug-induced or alcoholic hepatitis
Aspartate
Aminotransferase
6-20 U/L
20 x normal
Viral hepatitis, severe skeletal muscle
trauma, extensive surgery
10-20 x
normal
MI, mononucleosis, alcoholic
cirrhosis
5-10 x normal
Duchenne muscular dystrophy,
dermatomyositis, chronic hepatitis
2-5 x normal
Hemolytic anemia, metastatic hepatic
tumors, acute pancreatitis, pulmonary
emboli, delirium tremens, fatty liver
Alkaline Phosphatase
20-70 U/L
Sharp
Biliary obstruction
Moderate
Biliary obstruction, cirrhosis,
mononucleosis, viral hepatitis
Less than 20
Hypophosphatasia, protein or
magnesium deficiency
Gamma-Glutamyl
Transpeptidase
5-37 U/L
Sharp
Obstructive jaundice, hepatic
metastases
Moderate
Acute Pancreatitis, renal disease,
prostatic metastases, brain tumors
SOURCE:
Margaret Colyar , Dr.NS, FNP
Co-director NP
College of Nursing
University of Utah
Salt Lake City UT
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