Prevalence of macroenzymes creatine kinase, amylase and lipase in macroprolactinemia: A cross-sectional study

Objectives: Macroforms of proteins, including macroprolactin (mPRL) and macroenzymes, may interfere with immunoassay-based estimations, leading to diagnostic confusion. This study aimed to estimate the prevalence of macroenzymes (creatine kinase [CK], amylase and lipase) in patients with macroprolactinemia. Materials and Methods: This prospective, cross-sectional study was conducted at the Department of Biochemistry and Department of Endocrinology, ABVIMS and Dr. RML Hospital, New Delhi, between August 2022 and February 2024. A total of 100 patients with positive or borderline-positive macroprolactinemia detected by polyethylene glycol (PEG) precipitation were included. The prevalence of macroenzymes (CK, amylase and lipase) was determined using the PEG precipitation method. Statistical analysis: Data were analysed using the Statistical Package for the Social Sciences version 21. Fisher’s exact test was used to assess associations between variables. Results: Among 100 subjects, 31 were mPRL-positive (<40% recovery) and 69 were borderline-positive (40– 60% recovery). The prevalence of borderline-positive macro-CK and macroamylase was 3.22%, observed only in mPRL-positive subjects. No positive macroenzyme cases were found. Borderline-positive macrolipase was observed in 70.96% of mPRL-positive and 62.32% of borderline-positive cases, with p < 0.05 considered as significant association between mPRL and macroenzyme presence. Conclusions: Although macroprolactinemia is a recognised analytical phenomenon, its association with macroenzymes (CK, amylase and lipase) was not significant in this cohort. Screening for macroforms using PEG precipitation helps avoid diagnostic and therapeutic misinterpretations. Further large-scale studies are warranted to confirm these findings.