Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (42 page)

   Takayasu syndrome is the term for granulomatous arteritis of the aorta. Temporal arteritis and rheumatic disease may also be associated with aortitis.

   Greater incidence in young to middle-aged Asian females. Coronary involvement occurs in 15–25% of cases. Involvement is usually in segments and rarely diffuse.

   Average age of onset is 24 years, and the diagnosis should be considered in individuals of <40 years with acute myocardial infarction.

   Diagnosis is established by characteristic arteriographic narrowing or occlusion or histologic examination. Laboratory tests are not useful for diagnosis or to guide management.

   Laboratory Findings

Findings are due to involvement of coronary or renal vessels.

   Hematology: increased ESR is found in approximately 75% of cases during active disease but is normal in only 50% of cases during remission. WBC count is usually normal.

   Core laboratory: serum proteins are abnormal, with increased γ globulins (mostly composed of IgM). Female patients have a continuous high level of urinary total estrogens (rather than the usual rise during the luteal phase after a low excretion during the follicular phase).

THROMBOANGIITIS OBLITERANS (BUERGER DISEASE)

   Thromboangiitis obliterans is very rare and is the vascular inflammation and occlusion of medium and small arteries and veins of limbs; it is related to smoking and occurs mostly in males. Histology shows characteristic inflammatory and proliferative lesions. Coronary involvement is uncommon. Laboratory tests are usually normal.

INFECTIOUS (SECONDARY) VASCULITIS

   Definition

   Various microorganisms may cause vasculitis of any size vessel by either hematogenous spread or direct extension of cardiac structures involved (pericardium, valves).

   Most important infections of the coronary arteries are syphilis, tuberculosis, and syphilitic arteritis.

   Who Should Be Suspected?