Delta-ALA Porphyrin Urine test.
The Delta-ALA
urine test is a test that measures the
amount of delta-ALA in urine. It is one of the mmore
basic porphyria tests.
Delta-ALA
means delta-aminolevulinic acid. It is a basic
component
of the heme biopathway.
A 24-hour
urine sample collection of urine is needed.
An order for the test must be ordered by your personal
physician.
The physician will instruct you, if necessary, to
discontinue drugs
that will most likely compromise the results of the test.
Also check with your physician that the correct
preservative
is being used in the collection jug. There are
several
porphyrin urine tests and each has its own specified
preservative.
A few things
to remember about the tests is that light, air,
and heat will effect the outcome of the test because
these factors will
lower the porphyrin count in the collection. Be sure that
the cap is
securely screw onto the container to avoid the leakage of
air or
light into the container.
On day 1, urinate into the toilet upon arising in the
morning.
Collect all subsequent urine in the special plastic
"hat" for the next
24-hours.
On the second day urinate and pour all of the urine into
the container in
the morning upon arising. Cap the container. Keep it in
the refrigerator or a cool
place [36 to 40 degrees F.] during the entire collection
period.
Label the container with your name, the date, the time of
completion,
and return it as instructed by yopur physician.
Submit the
collection to the laboratory or your
physician as soon
as possible upon completion of the test. Be sure
that it is properly stored
in refrigeration and not left on the counter in the light
and heat.
It would be good to walk with the lab tech to the storage
area and
also find out the time it will be transfered to the
assaying lab, and
expected time of results. Be sure to always follow
through on the
test during the entire process to avoid the test being
compromised in some way.
Avoid exposure
of the urine to direct light. The best results for
this test happen when the urine is voided in complete
darkness and
poure directly into the collection jug in the dark or
very dim
indirect light. This test is useful in detecting specific
liver abnormalities and
is a good indicator test for patients suspected of having
porphyria.
Delta-ALA is a
chemical produced from amino acids in the liver.
It is the basic "building block" for the
synthesis of porphyrins.
The most important function of porphyrins are as
components
of heme. Heme is the major building block of
hemoglobin.
Oxygen binds to the iron in the heme molecules.
Various kinds
of porphyrins exist with the same basic structure
but with slightly different chemical "side-chains".
The major biochemical pathway is:
delta-ALA
PBG
uroporphyrin
coproporphyrin
protoporphyrin
heme
Each step in
the pathway requires a specific enzyme.
If any of the enzymes is deficient, them a type of
porphyria results.
Normal values 1 to 7 mg per 24-hours
Before
starting this test be sure that you are NOT taking any
drugs
which may compromise the test results.
Drugs that may
increase test measurements include penicillin,
barbiturates, oral contraceptives, and griseofulvin.
Increased
abnormal levels of urinary delta-ALA may indicate
many types of porphyria. In addition increased levels may
indicate lead poisoning. Decreased levels may occur with
chronic liver disease.
Dr. Robert Johnson MD
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PBG Urine testing
The PBG Urine test is a test that measures the
amount
of porphobilinogen in the urine. Another name for
the test is the PHB test.
The test of completed by collecting a 24-hour urine
sample.
The test must be ordered by your physician.
Your physician will instruct
you as to what drugs you may have to
discontinue because some drugs may interfere with
the test results. It is impereative that you do not use
certain drugs or use any alcohol for a week prior to
collection of the test.
Also please note that you are NOT to undergo glucose
injection or infusion until after the collection has been
made. The use of glucose will dramatically reduce
porphyrin levels in the test results.
Before you leave the physician's office, be sure that the
collection jug has the correct preservative within the
jug. On day 1,
urinate into the toilet upon arising in the morning.
Collect all
subsequent urine in a special container called a "hat"
for the next 24-hours.
But sure to
try and void in as limited of light as possible. Exposure
of the urine to light will diminish the total porphyrins
and the object of the test is to have as high as possible
count of porphyrins.
Also note that
of the collection toexposure to air will diminish
the porphyrins and therefore you should never let the
voided urine stand in
the hat, but immediately.
On day 2,
urinate into the "hat" and immediately
pout into the
container in the morning upon arising.
Be sure that
the cap is on the container at all times.
Keep it in the refrigerator or a cool place during the
collection period.
Be sure that
the collection jug is labeled with your name, the date,
the time of completion.
Then the
next step is to return the collection jug
as instructed
by your physician. To safeguard your collection and
to be sure that
it is not compromised, accompany it to the lab, and go
with it to the
area where it is being stored and see it safety
refrigerated. Remember that
many a collection sample has been compromised because it
was left unattended on a lab counter in light and heat.
Ask questions.
Find out when it is being shipped and to whom. When it is
expected to arrive and when the results are expected to
be completed and returned.
Following the
directions of your phyrisician immediately deliver the
collection jug. Be sure that it is refrigerator
upon receipt.
This test may is performed when porphyria or
another disorder
associated with abnormal PBG level is suspected.
PBG is a substance (enzyme) used by the body to
synthesize
porphyrins (nitrogen containing organisms).
The important function of porphyrins is as components of
heme.
Heme is made
from iron + protoporphyrin. Hemoglobin is made up of four
globin proteins + 4 heme groups. Oxygen binds to the iron
in the heme molecules.
Various kinds of porphyrins exist with the same basic
structure,
but with slightly different chemical appearance.
The major biochemical pathway includes conversions from
porphyrins to delta-ALA, then to PBG, then uroporphyrin,
then coproporphyrin, then protoporphyrin, and finally
into the end product, heme.
Each step requires the presence of an enzyme. If any of
the enzymes are deficient (because of a genetic disease
or inhibition by a toxic substance), a type of porphyria
results. The following are the normal values for the PBG
24-hour urine test. 1.5 to 2 mg (milligrams) per 24-hours
Many drugs can affect the results of the PBG 24 urine
test. Drugs that can affect test measurements include
aminosalicylic
acid, barbiturates, chloral hydrate, chlorpropamide,
ethyl alcohol, griseofulvin, morphine, oral
contraceptives, phenazopyridine, procaine, and
sulfonamides. Abnormal increased levels of urinary PBG
may indicate several types of porphyria. In addition
elevated PBG may indicate hepatic carcinoma (liver cancer)
, cirrhrosis, hepatitis, and lead poisoning.
Dr. Robert Johnson MD
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24 HOUR PORPHYRIN URINE TEST
The Porphyrin
Urine Tests is a test that measures the level of
porphyrins in urine.
An alternative
name for this test is The Uropoprhyrin Test.
The test is
performed by the collection of a urine for a 24-hour
period.
The test must
be ordered by a physician. The ordering physician
will instruct you, if necessary, to discontinue
drugs that may interfere with the test.
Be sure that
the proper preservative has been added to the
collection jug before leaving your doctor's office. Many
a porphyrin urine
test has been compromised because of the wrong
perservative being used or lack of a preservative.
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.
Always cap the
container.
Always void
into a special "hat" which fits into the
average toilet seat.
Do not let the
voided urine sit in the hat. Pour it immediately
into the collection jug. Exposure to air will compromise
the collection.
Try to void
with no direct light as exposure of urine to light
will
diminish the number of porphyrin, and the higher number
of porphyrin
in the urine, is what is needed for an accurate
test assay.
Be sure that
no toilet tissue touches the collection as chemicals
in paper products will compromise the collection.
Keep it in the
refrigerator or a cool place during the collection
period. Ideally the temperature should run between
36-40 degrees, that of
the standard refrigerator setting.
Always be sure
that the container is marked with your name, the
date, the time of completion, and return it as instructed.
Do not let it sit
out in room temperatures or in bright light.
Be sure the receptionist at the lab
takes it to the proper storage
in the lab immediately. Ascertain that it has been
properly stored
at the lab. Find out when it will be transported
and how it will be
transported to the assaying laboratory. ALso find out
when the assay is to
be run and when the results will be know. Asking
these questions helps
alleviate any problems of a lost specimen and/or
compromised tests results. There are no risks in
performing this test.
The reason that this test is performed
is because of a high degree of
suspicion that the patient may have porphyria.
The most
important function of porphyrins is as components of heme.
Heme is made from iron + protoporphyrin.
Hemoglobin is
made up of four globin proteins + 4 heme groups.
Oxygen binds to the iron in the heme molecules.
Various kinds
of porphyrins exist with the same basic structure.
However the various kinds of porphyrins have
slightly different chemical
appearance.
The major
biochemical pathway includes conversions from
porphyrins to delta-ALA, then to PBG, then uroporphyrin,
then coproporphyrin, then protoporphyrin, and finally
into the end product, heme.
Each step
requires the presence of an enzyme. If any of the enzymes
are deficient (because of a genetic disease or inhibition
by a toxic
substance), a type of porphyria results. Normal values
for porphyria
urine tests are as follows: random urine: negative test
24-hour urine: 50 to 300 mg per 24-hours Note: mg =
milligrams
Before you
undertake this porphyrin urine test you must determine
whether you have taken any drugs which can affect test
measurements.
These drugs
include aminosalicylic acid, barbiturates, chloral
hydrate, chlorpropamide, ethyl alcohol, griseofulvin,
morphine, oral
contraceptives, phenazopyridine, procaine, and
sulfonamides.
Abnormal tests
results which result in increased levels of urinary
PBG may indicate porphyria (several types), hepatic
carcinoma (liver
cancer), hepatitis or lead poisoning .
All too often
porphyrin tests must be repeated a number of times.
Timing is important for many of the tests. The best time
to test is
at the onset of an acute attack and BEFORE
GLUCOSE infusion has begun.
Dr. Robert Johnson, MD
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Problems with Porphyrin Urinary
Testing in a Hospital Setting
As I recall
a porphyria patient of mine, the urinary porphyrin
test would not show anything for her time and again
when she would go into an attack over a weekend or when I
was on vacation.
She would fo
to the ER and instead of regarding the diagnostic urinary
testing as a priority, they would finish placing her i.v.
line and instead of waiting while she completed the
testing , they would immediately begin the glucose.
When
gluocse is started, it immediately begins to
repress the over productions of porphyrins in the liver.
By the time the 24 hours is completed there are no
or very little porphyrin population left in urine.
The laboratory will find nothing. And then
generally the phyhsicians reviewing the test results will
assume that the patient is not porphyric based upon the
results.
This problem
continued for several years unless one day
she came to the clinic directly and I told her she could
do just
as well at home for 24 hours and then I would admit here
because our
facility was at a capacity level and medically there was
nothing we could
not do for her at home.
Then the
test came back uncompromised and the results
were most dramatic. Very elevated and beyond a doubt.
Then the
problem was for me to figure out why this had not been
the case
with previous testings.
After
reviewing charts and procedures it was clear that
the admitting doctors did not understand the
connection between
testing and compromised collection if administered
glucose.
Even between
acute crises this patient had spot checked
with high urinary porphyrin levels, although for many
patients
such spot checks fail to show any elevation during times
of remission.
My
admonishment is to not expect a positive result for
your urine
test if it is administered at the hospital and you are
placed on glucose.
The best time
to have urine and stool 24h tests is when you begin
to have symptoms but do not need to go to ER. When
you follow through here, if you are porphyric, your test
results will in this case the level will be very
high most likely.
Dr. Robert Johnson M.D.
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