Validation of an automated immune turbidimetric assay for serum gelsolin and its possible clinical utility in sepsis

• Published in: Journal of clinical laboratory analysis 2018-03, Vol.32 (3), p.n/a
• Main Authors: Horváth‐Szalai, Zoltán, Kustán, Péter, Szirmay, Balázs, Lakatos, Ágnes, Christensen, Per H., Huber, Tamás, Bugyi, Beáta, Mühl, Diána, Ludány, Andrea, Miseta, Attila, Kovács, Gábor L., Kőszegi, Tamás
• Format: Article
• Language: English
• Subjects: Actin; Adult; Aged; Aged, 80 and over; Automation; Automation, Laboratory - methods; diagnostic marker; Female; Gelsolin; Gelsolin - blood; Humans; immune turbidimetry; Inflammation; Limit of Detection; Linear Models; Male; Middle Aged; Nephelometry and Turbidimetry - methods; Quantitation; Reproducibility of Results; ROC Curve; Sepsis; Sepsis - blood; Sepsis - diagnosis; serum gelsolin; Systemic inflammatory response syndrome
• ISSN: 0887-8013; 1098-2825
• DOI: 10.1002/jcla.22321

Background Studies showing the potential predictive value of the actin‐binding protein gelsolin, in critically ill patients are scarce. Moreover, even up to now a rapid automated measurement of gelsolin has still remained a challenge. Therefore, we developed and validated an automated serum gelsolin immune turbidimetric assay for possible clinical use. Methods Validation of serum gelsolin assay was performed on a Cobas 8000/c502 analyzer (Roche) according to the second edition of Eurachem guidelines. Furthermore, we also studied the diagnostic value of serum gelsolin in sepsis when investigating sera of septic (n = 25), systemic inflammatory response syndrome (SIRS; n = 8) and control patients (n = 14). We compared our previously published Western blot data with those of the new turbidimetric assay. Results The sample volume was 7 μL and the assay time was 10 minutes. The detection limit was 0.72 mg/L, intra‐ and inter‐assay imprecision remained in most cases less than 5% expressed as CV. Recovery was found to be 84.56%‐93.52% and linearity study gave an appropriate correlation coefficient by linear regression analysis (r2 = .998). Septic patients exhibited lower (P = .015) first‐day serum gelsolin levels than SIRS patients, which confirmed our previous Western blot results. The determined cut‐off point for serum gelsolin was 14.05 mg/L (sensitivity: 75%; specificity: 60%) when investigating its diagnostic value in sepsis. Conclusion Based on the results, our immune turbidimetric measurement offers a rapid and accurate quantitation of gelsolin in human serum samples. Serum gelsolin seems a promising additional diagnostic marker of sepsis which has to be further investigated.