Protein electrophoresis is commonly used as an aid in the diagnosis of monoclonal gammopathies and is performed in many laboratories in Canada and throughout the world. However, unlike many other diagnostic tests, there is limited guidance for standardization and neither guidance nor specific recommendations for clinical reporting of serum (SPE) or urine (UPE) protein electrophoresis and immunotyping available in the literature. Therefore, a Canadian effort was undertaken to recommend standards that cover all aspects of clinical reporting with an ultimate goal towards reporting standardization. The Canadian Society of Clinical Chemists (CSCC) Monoclonal Gammopathy Interest Group (MGIG), which is composed of CSCC members with an interest in protein electrophoresis, has formed a Monoclonal Gammopathy Working Group (MGWG) to take initial steps towards standardization of SPE, UPE and immunotyping. Candidate standardization recommendations were developed, discussed and voted upon by the MGWG. Candidate recommendations that achieved 90% agreement are presented as consensus recommendations. Recommendations that did not achieve 90% consensus remain candidate recommendations and are presented with accompanying MGWG discussion. Eleven consensus recommendations along with candidate recommendations for nomenclature, protein fraction reporting, test utilization, interference handling and interpretive reporting options are presented.

Chronic kidney disease (CKD) is a major public health problem. Estimated glomerular filtration rates based on serum creatinine values are used to diagnose this condition, and accuracy of laboratory testing is a crucial step in diagnosing and managing these patients efficiently in a timely manner. Spuriously elevated creatinine values have been reported due to the interference of other substances, including paraproteins. Paraproteins can interfere with the determination of various clinically important analytes in an unpredictable manner. While mild to moderate degrees of interference affecting the measurement of serum creatinine values have been previously reported, we present a case of a patient with markedly elevated serum creatinine who was referred for emergent assessment for possible consideration of renal replacement therapy. A thorough history and repeat laboratory investigations at several laboratories ultimately revealed the initial serum creatinine level to be spuriously high, i.e. "pseudohypercreatinimea" due to immunoglobulin interference. Further investigations ultimately led to the diagnosis of Waldenstrom's macroglobulinemia and the patient was appropriately treated. However, this case sheds light on the importance of being aware of a spuriously high creatinine value and its possible causes, as it can have significant diagnostic implications.