BACKGROUND: The determination of κ free light chains (KFLC) in cerebrospinal fluid (CSF) by nephelometry is a feasible alternative to immunoglobulin G oligoclonal bands (OCB) in the evaluation of intrathecal synthesis of immunoglobulin in multiple sclerosis (MS) and other demyelinating diseases. The aim of this study was to assess the diagnostic value of KFLC and its inclusion in a procedure algorithm along with OCB interpretation. METHODS: A cross-sectional study, which included 123 patients with a CSF OCB request, was carried out. Isoelectric focusing followed by immunofixation was used to detect OCB, and nephelometry was used to analyze KFLC. The KFLC index was calculated using CSF/serum quotient of KFLC and albumin. The KFLC index was compared with MS diagnosis to find the optimal cutoff. It was obtained from the receiver operating characteristic (ROC) curves and the Youden method. RESULTS: The CSF KFLC median was 1.66 mg/L in the MS group, whereas in other central nervous system diseases, KFLC showed generally no or only moderate increase in CSF (median 0.10 mg/L). KFLC index showed a significant difference between groups. ROC analysis for CSF KFLC concentration, and KFLC indexes were 91.88% and 93.94%, respectively. The best cutoff for the KFLC index was 2.91 for MS diagnosis (sensitivity: 83.78%; specificity: 85.88%). The proposed algorithm showed high sensitivity (89.19%) and specificity (84.71%). CONCLUSIONS: KFLC determination is rapid and automatized, but it has no higher sensitivity and specificity than OCB in MS diagnosis. Nevertheless, when used in screening, it could reduce the number of manual OCB tests.
BACKGROUND: The determination of κ free light chains (KFLC) in cerebrospinal fluid (CSF) by nephelometry is a feasible alternative to immunoglobulin G oligoclonal bands (OCB) in the evaluation of intrathecal synthesis of immunoglobulin in multiple sclerosis (MS) and other demyelinating diseases. The aim of this study was to assess the diagnostic value of KFLC and its inclusion in a procedure algorithm along with OCB interpretation. METHODS: A cross-sectional study, which included 123 patients with a CSF OCB request, was carried out. Isoelectric focusing followed by immunofixation was used to detect OCB, and nephelometry was used to analyze KFLC. The KFLC index was calculated using CSF/serum quotient of KFLC and albumin. The KFLC index was compared with MS diagnosis to find the optimal cutoff. It was obtained from the receiver operating characteristic (ROC) curves and the Youden method. RESULTS: The CSF KFLC median was 1.66 mg/L in the MS group, whereas in other central nervous system diseases, KFLC showed generally no or only moderate increase in CSF (median 0.10 mg/L). KFLC index showed a significant difference between groups. ROC analysis for CSF KFLC concentration, and KFLC indexes were 91.88% and 93.94%, respectively. The best cutoff for the KFLC index was 2.91 for MS diagnosis (sensitivity: 83.78%; specificity: 85.88%). The proposed algorithm showed high sensitivity (89.19%) and specificity (84.71%). CONCLUSIONS: KFLC determination is rapid and automatized, but it has no higher sensitivity and specificity than OCB in MS diagnosis. Nevertheless, when used in screening, it could reduce the number of manual OCB tests.
Authors: C E Leurs; Ham Twaalfhoven; B I Lissenberg-Witte; V van Pesch; I Dujmovic; J Drulovic; M Castellazzi; T Bellini; M Pugliatti; J Kuhle; L M Villar; J C Alvarez-Cermeño; R Alvarez-Lafuente; H Hegen; F Deisenhammer; L M Walchhofer; E Thouvenot; M Comabella; X Montalban; L Vécsei; C Rajda; D Galimberti; E Scarpini; A Altintas; K Rejdak; J L Frederiksen; G Pihl-Jensen; Peh Jensen; M Khalil; M M Voortman; F Fazekas; A Saiz; D La Puma; M Vercammen; L Vanopdenbosch; Bmj Uitdehaag; J Killestein; C Bridel; C Teunissen Journal: Mult Scler Date: 2019-05-08 Impact factor: 6.312
Authors: Frida Duell; Björn Evertsson; Faiez Al Nimer; Åsa Sandin; Daniel Olsson; Tomas Olsson; Mohsen Khademi; Max Albert Hietala; Fredrik Piehl; Magnus Hansson Journal: Neurol Neuroimmunol Neuroinflamm Date: 2020-06-11
Authors: Franz Felix Konen; Philipp Schwenkenbecher; Konstantin Fritz Jendretzky; Stefan Gingele; Kurt-Wolfram Sühs; Hayrettin Tumani; Marie Süße; Thomas Skripuletz Journal: Cells Date: 2021-11-06 Impact factor: 6.600
Authors: Franz Felix Konen; Philipp Schwenkenbecher; Konstantin Fritz Jendretzky; Stefan Gingele; Torsten Witte; Kurt-Wolfram Sühs; Matthias Grothe; Malte Johannes Hannich; Marie Süße; Thomas Skripuletz Journal: Brain Sci Date: 2022-04-03