Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (713 page)

   Lower secretion occurs in recumbency, hypoosmolality, volume expansion, and hypertension.

   Plasma sample should not be left at room temperature.

ANTIHYPERTENSIVES

See Cardiovascular Drugs.

ANTI-INFLAMMATORIES

See Acetaminophen, Salicylates.

ANTINEOPLASTICS

See Methotrexate.

ANTIMITOCHONDRIAL ANTIBODIES

   Definition

   Mitochondrial antibodies are found in a variety of liver diseases and have been characterized to react with at least nine different mitochondrial antigens (M1–M9). M2, M1, and M7 are antigens on the inner mitochondrial membranes while the M3, M4, M5, M6, M8, and M9 antigens are present on the outer membranes. Antibodies to the M2, M4, M8, and M9 antigens are found in patients with PBC. About 95% of patients with PBC will be positive for anti-M2. When M4 and M9 are also present, the patient usually has a more rapidly progressive disease course. Some PBC patients (<5%) may only have anti-M9. These patients are usually early in the disease course and may have a more limited disease.

   
Normal range:

   Immunofluorescence assay (IFA): negative, if positive, results are tittered, ELISA: <1:40 titer.

   AMA titers >1:40 are significant.

   Use

   Diagnosis of primary biliary cirrhosis (PBC)

   Interpretation

Increased In

   Ninety-five percent of PBC cases

Decreased In

   NA

   Limitations