Abstract
Objective: Presentation of current knowledge of clinical issues of macro-complexes and possibilities of their detection. Clinical problems of macro-complexes are evaluated on the basis of literature review.
The types of macro-complexes, their association with diseases and frequency of occurrence are listed. Furthermore, current possibilities of detection of macro-complexes are reported.
Results: Macro-complexes are most often formed by binding of enzyme and immunoglobulin G (IgG). This may be either non-specific binding or binding with specific autoantibodies circulating in the serum.
Macro-amylase was the first described macro-enzyme, which is reported most frequently together with macro-AST. Due to the increasing sensitivity of laboratory methods, macro-troponins and other macro-proteins are currently captured.
The prevalence of macro-complexes in serum is not fully known, it varies in each particular macro-complex in studies, and is reported from 0.5% (macro-TSH) to 20.4% (macro-troponin). The presence of the macro-complex is considered to be a benign finding that occurs both in completely healthy individuals without symptoms and in association with autoimmune (especially systemic lupus erythematosus) and other diseases (malignancies, inflammatory diseases, etc.).
Conclusion: In case of persistent isolated increase in enzyme or protein without proven causes, attention should be paid to the possibility of the presence of the macro-complex in the patient's serum or other possible interferences (presence of heterophilic antibodies, rheumatoid factor, hemolysis, etc.). Effective communication between the clinician and the laboratory is therefore essential for the discrepancy of results both for the capture and detection of suspected macro-complexes and for the detection of other interfering substances in the serum sample.