Abstract
Despite advances in modern medicine, classic laboratory parameters are still crucial pillars of clinical decision-making. The report focuses on four routinely measured analytes: serum creatinine levels, liver transaminase activities and albumin levels. In 2024, these accounted for more than 15% of laboratory determinations in Hungary. Laboratories measure serum creatinine levels using two methods: the Jaffé or the enzymatic method. Although both are suitable for estimating the glomerular filtration rate (GFR), the results may differ by 5-14% from each other. According to the professional opinion, both methods can be used, but they should be indicated on the report. The presence of pyridoxal phosphate (vitamin B6) in the reagent is critical for the determination of transaminase activities (GOT/AST, GPT/ALT). In its absence, the measured values may be 15-30% lower, which may lead to misdiagnosis, especially when calculating the FIB4 score for estimating the severity of liver fibrosis. Therefore, the use of reagents containing pyridoxal phosphate is recommended for measuring transaminase activities. In the case of albumin determination, the use of bromocresol red reagent is recommended instead of bromocresol green, as the former gives inaccurate results in liver disease and renal failure. Method changes should be made in consultation with clinicians, and it should be noted that the LOINC codes (an international standard for parameter identification) for the tests may change.