Influence of Methodology on the Detection and Diagnosis of Congenital Analbuminemia

Congenital analbuminemia is a rare recessive inherited disorder characterized by an absence or very low concentrations of serum albumin (1)(2). The diagnosis of analbuminemia is suggested by persistent hypoproteinemia with adequate hepatic function and a lack of evidence for either a renal or gastrointestinal protein loss. The diagnosis is typically confirmed by serum protein electrophoresis that depicts an absence of an albumin band (3). Rapid diagnosis of analbuminemia is appealing because patients can be subjected to extensive and prolonged testing to ascertain the cause of their apparent protein-losing disorder. Unfortunately, the diagnosis of analbuminemia may be delayed by clinically misleading laboratory results generated by tests of analytes that are usually bound to albumin, e.g., calcium (4) and thyroxine (5), and tests sensitive to the concentration of albumin in the matrix, e.g., some free thyroxine immunoassays (6)(7). In particular, rapid diagnosis of analbuminemia would be delayed if the method for serum albumin falsely reports the presence of albumin.