Analysis of five cases showing false-high Hemoglobin A1c due to reduced catalase activity

Endocr J. 2023 Nov 28. doi: 10.1507/endocrj.EJ23-0212. Online ahead of print.ABSTRACTWe encountered five cases that exhibited false-high Hemoglobin A1c (HbA1c) levels when samples were examined using the enzyme-based NORUDIA N HbA1c kit. HbA1c levels were higher than those obtained using other methods, such as HPLC, immune-based methods, and other enzyme-based kits. This kit produced inaccurate results for HbA1c when residual peroxides were present in samples. The addition of peroxidase solution restored false-high HbA1c levels in the five cases, indicating that reduced catalase activity was responsible for these values because catalase eliminates peroxide. Catalase activity and gene mutations were examined in the five cases and an immunohistological analysis was performed to assess the expression of catalase. Cases #1 and 2 were diagnosed as acatalasemia and cases #3, 4, and 5 as hypocatalasemia based on compound heterozygous SNP and heterozygous splicing mutations in the catalase gene. Therefore, impaired catalase activity was responsible for false-high HbA1c levels measured by the NORUDIA N HbA1c kit.PMID:38030260 | DOI:10.1507/endocrj.EJ23-0212

Source: Endocrine Journal - November 29, 2023 Category: Endocrinology Authors: Kenji Hara Atsushi Ujiie Shiori Suzuki Takenori Okumura Mio Kubo Hiroyuki Shinozaki Mototaka Yamauchi Takafumi Tsuchiya Kohzo Takebayashi Nobuyuki Shimozawa Masafumi Koga Koshi Hashimoto Source Type: research