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Q: What Blood Test Results Mean ( Answered,   0 Comments )
Subject: What Blood Test Results Mean
Category: Health > Conditions and Diseases
Asked by: dawn88-ga
List Price: $10.00
Posted: 15 Aug 2006 12:18 PDT
Expires: 14 Sep 2006 12:18 PDT
Question ID: 756265
Anca Screen Blood Test Done, Positive Result P-Anca.  Confirmatory
Test Done, Strong Anti-MPO Activity.  C-Anca Negative.  Doctor is
sending me to a Rheumatologist.  What does this mean?
Subject: Re: What Blood Test Results Mean
Answered By: crabcakes-ga on 15 Aug 2006 21:41 PDT
Hello Dawn88,

  Your doctor is referring you to an rheumatologist because s/he
suspects you MAY have a connective tissue disease such as rheumatoid
arthritis, polyangiitis, vasculitis, SLE (Systemic lupus
erythematosis), Sjogren?s or some other undifferentiated disease. The
rheumatologist will likely request more specific tests after examining
you and reviewing your medical history.

 The fact that you have a negative C-ANCA rules out Wegener's
Granulomatosis. A positive P-ANCA can indicate immuno-vasculitis,
glomerulonephritis, C-S syndrome, polyarteritis nodosa, SLE, and RA

   Strong Anti-MPO Activity - ?Presence of anti-MPO antibodies is
highly specific for idiopathic and vasculitis-associated crescentic
glomerulonephritis, classic polyarteritis nodosa, Churg-Strauss
syndrome, and polyangiitis overlap syndrome without renal involvement.
Levels of anti-MPO are elevated during active phases of disease and
lower during remission. Therefore, monitoring anti-MPO levels can aid
in disease management.?

   ?ANCA are antibodies found in the blood in most people with
Wegener's granulomatosis, a disease that affects the upper respiratory
tract, lungs, and kidneys. They are uncommon in other diseases, which
makes them useful in diagnosing this particular disease.?

?Normal Range = none present. 
ANCA is the antibody to white cells
It is found in approx 20% lupus patients, lupus specificity is poor.
C-ANCA suggests a systemic vasculitis disease, and is rarely seen in
patients with lupus.
P-ANCA is most seen in necrotizing, crescentic glomerulonephritis and
polyarteritis nodosa. P-ANCA is found in some lupus patients.?

 A positive P-ANCA can indicate:
?microscopic polyangiitis
?idiopathic glomerulonephritis
?Churg-Strauss syndrome
?primary sclerosing cholangitis

You can click the links on this page to find more about each condition:

A Positive P-ANCA can also indicate:
P-ANCA is useful in differentiating IBD from other diarrheal disease.8

A positive P-ANCA pattern along with a negative S. cerevisiae
antibodies result strongly suggests UC7

UC and CD, P-ANCA are generally positive in patients with a more
aggressive disease course and are less responsive to treatment;
however, they can also be positive in patients who respond to

The sensitivity of ANCA testing in UC increases from 56% to 78% by
combining IgG and IgA ANCA assays.

Specialty also tests for ANA as these antibodies can generate a
P-ANCA-like pattern.

More on a positive P-ANCA
?Churg-Strauss syndrome (C-Ss) of allergic granulomatosis (a syndrome
of asthmatics)
?necrotizing and crescentic glomerulonephritis (n/cGN)
?small vessel vasculitis/microscopic polyarteritis nodosa
(MPA)/microscopic polyangiitis [60% of cases MPO positive]
?"false positives" [not  C-Ss, n/cGN, or MPA] 
osystemic polyarteritis nodosa (but positivity so rare in this disease
that great caution urged in making a diagnosis in the face of a
positive ANCA)
o Goodpasture's syndrome/anti-GBM-positive renal disease
o 11%  of cases of giant-cell arteritis
o giant-cell arteritis
o Felty's syndrome
o atypical pneumonia cases
o post-streptococcal glomerulonephritis
o systemic lupus erythematosus
o mixed connective tissue disease (MCTD)
o about 25% of WGs have this MPO positivity
o MPO ANCA develops in many people on hydralazine therapy4

   ?The ANCA blood test has been shown to be very valuable in the
diagnosis and follow-up of patients with Wegener's Granulomatosis. It
is a very helpful test in early cases in which the diagnosis is not
very clear, and in patients who already have been diagnosed with
Wegener's and have a flare, to know if the flare is due to concurrent
infection or due to a flare of the disease itself. It is a very
helpful guide to determine the treatment and whether the disease is
improving and is in remission or not. Every Wegener's patient should
have the test done to confirm the diagnosis and follow the disease

   ?There are two kinds of ANCA -- one called cytoplasmic and
abbreviated as C-ANCA; and the other called perinuclear, abbreviated
P-ANCA. This has been very helpful to differentiate between Wegener's
Granulomatosis in which the type of the test is C-ANCA and another
related disease called microscopic polyarteritis in which there is
inflammation of the blood vessels (small ones, particularly in the
kidneys) in which the test is P-ANCA.?

I hope this has helped you out! Please request an Answer
Clarification, and allow me to respond before you rate, if anything is

I wish you the best!

Sincerely, Crabcakes

Search Terms

ANCA testing
P-ANCA + antibodies
C-ANCA + antibodies
Antimyeloperoxidase  antibodies or MPO antibodies
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