If we started depending upon
laboratory tests then most of the autoimmune
diseases would go undetected.
It is by history alone, then physical findings
that a autoimmune disorder needs to be diagnosed.
The best tests are SED RATE,
CRP, ASO TITER.
Sed rate is the cheapest test and the oldest and simplest one
to measure inflammation.
the ESR: Key Considerations
- The ESR is an inexpensive,
simple test of chronic inflammatory activity.
- Indications for the ESR have
decreased as the sophistication of laboratory testing has
- The ESR rises with age, but
this increase may simply reflect a higher disease prevalence in
- The use of the ESR as a
screening test in asymptomatic persons is limited by its low
- An elevated ESR is a key
diagnostic criterion for polymyalgia rheumatica and temporal
arteritis, but normal values do not preclude these conditions.
- When there is a moderate
suspicion of disease, the ESR may have some value as a "sickness
- An extremely elevated ESR (>100
mm/hr) will usually have an apparent cause--most commonly
infection, malignancy or temporal arteritis.
- A mild to moderately elevated
ESR without obvious etiology should prompt repeat testing after
several months rather than an expensive search for occult
Screening for Systemic Disease or Neoplasia
Unfortunately, the ESR is neither sensitive nor specific when used as a
general screening test. For instance, the ESR may be elevated in the presence of
infectious disease, other inflammatory or destructive processes, collagen
vascular disease or malignancy,1-3 but it may
not be increased in a number of infectious diseases (e.g., typhoid fever,
malaria, mononucleosis), allergic processes, angina (as opposed to myocardial
infarction) or peptic ulcer disease (as opposed to active inflammatory bowel
Because an elevated ESR may occur in so many different clinical settings,
this finding is meaningless as an isolated laboratory value. In addition, some
patients who have malignant tumors, infections or other inflammatory disorders
will have normal ESR values. Most unexplained ESR elevations are short-lived and
not associated with any specific underlying process. In those instances where
disease is present, it will usually be obvious after completion of history
taking, physical examination and collection of routine laboratory data.
It is not a new test, but it is a test in the news. CRP, also known as
C-Reactive Protein, is a test which measures the concentration in blood serum of
a special type of protein produced in the liver that is present during episodes
of acute inflammation or infection.