Re: Key Concept: Immunologic tests are not useful as screening tests

[Guest guest]

I wish we could send this to every doctor. It is amazing how many doctors

know very little about rheumatic diseases.

a

On 5/30/04 12:16 AM, " " <Matsumura_Clan@...> wrote:

> Medscape

> Introduction to Rheumatic Diseases

>

>

> Key Concept/Objective: To understand that immunologic tests are not

> useful as screening tests.

>

>

> As a class, immunologic tests have low specificity and only moderate

> sensitivity. They are more expensive than other clinical laboratory

> tests, and the results are less reproducible. Immunologic tests should

> never be used as screening tests; their greatest utility occurs when the

> pretest probability of disease is high. The misuse of immunologic tests

> frequently confounds the diagnosis and leads to unnecessary rheumatology

> referrals. The use of so-called arthritis panels, in which many

> serologic tests are bundled together, increases the likelihood of an

> abnormal test result occurring in a patient without rheumatic disease;

> such panels should be avoided. It is common for young women to test

> positive for ANA; approximately 32% of young women will test positive

> for ANA at low titers. A positive ANA in and of itself is by no means

> diagnostic of systemic lupus erythematosus. The probability of testing

> positive for rheumatoid factor increases with age even in healthy

> persons. Additionally, conditions other than rheumatoid arthritis can be

> associated with elevations in rheumatoid factor; because of this, a

> positive test result for rheumatoid factor is not diagnostic of

> rheumatoid arthritis. A careful and detailed history is the most

> important part of the evaluation of a patient with arthritis. Laboratory

> findings should be evaluated in the context of the information obtained

> by a detailed history and physical examination. Diagnoses of rheumatic

> diseases should not be based solely on the findings of immunologic

> tests.

>

>

> http://www.medscape.com/content/2003/00/46/35/463550/ans8.html

>

>

>

>

> I'll tell you where to go!

>

> Mayo Clinic in Rochester

> http://www.mayoclinic.org/rochester

>

> s Hopkins Medicine

> http://www.hopkinsmedicine.org

>

>

>

>

[Guest guest]

a,

I agree with you, and so would my oncologist! He was very interested

in the fact that the biggest reaction I had to the Interferon was in

all my joints! I felt like I was literally being torn apart from the

inside out, and my hips, elbows, knees, and knuckles were hot, even

when I got to the doctor on Monday. He could not explain it, and my

sed rate was only slightly elevated. The only explanation he could

give is that " Dercum's is autoimmune, but it may take years to find

out what the mechanism is. " Oh goody.

Judi

>

> > Medscape

> > Introduction to Rheumatic Diseases

> >

> >

> > Key Concept/Objective: To understand that immunologic tests are

not

> > useful as screening tests.

> >

> >

> > As a class, immunologic tests have low specificity and only

moderate

> > sensitivity. They are more expensive than other clinical

laboratory

> > tests, and the results are less reproducible. Immunologic tests

should

> > never be used as screening tests; their greatest utility occurs

when the

> > pretest probability of disease is high. The misuse of immunologic

tests

> > frequently confounds the diagnosis and leads to unnecessary

rheumatology

> > referrals. The use of so-called arthritis panels, in which many

> > serologic tests are bundled together, increases the likelihood of

an

> > abnormal test result occurring in a patient without rheumatic

disease;

> > such panels should be avoided. It is common for young women to

test

> > positive for ANA; approximately 32% of young women will test

positive

> > for ANA at low titers. A positive ANA in and of itself is by no

means

> > diagnostic of systemic lupus erythematosus. The probability of

testing

> > positive for rheumatoid factor increases with age even in healthy

> > persons. Additionally, conditions other than rheumatoid arthritis

can be

> > associated with elevations in rheumatoid factor; because of this,

a

> > positive test result for rheumatoid factor is not diagnostic of

> > rheumatoid arthritis. A careful and detailed history is the most

> > important part of the evaluation of a patient with arthritis.

Laboratory

> > findings should be evaluated in the context of the information

obtained

> > by a detailed history and physical examination. Diagnoses of

rheumatic

> > diseases should not be based solely on the findings of immunologic

> > tests.

> >

> >

> > http://www.medscape.com/content/2003/00/46/35/463550/ans8.html

> >

> >

> >

> >

> > I'll tell you where to go!

> >

> > Mayo Clinic in Rochester

> > http://www.mayoclinic.org/rochester

> >

> > s Hopkins Medicine

> > http://www.hopkinsmedicine.org

> >

> >

> >

> >