Diagnosis of IgG4-Related Hypertrophic Pachymeningitis (IgG4-HP) relies on meningeal biopsies, because cerebrospinal fluid (CSF) diagnostic biomarkers are lacking. Here, we determined whether IgG4 intrathecal production could distinguish IgG4-HP from other disorders presenting with HP (OHP). ⋯ An IgG4Loc cut-off of 0.47 identified 100% of IgG4-HP and no cases of OHP. Our results support CSF IgG4 quantification and IgG4 Indices as alternatives to meningeal biopsy for the diagnosis of IgG4-HP when this procedure is contraindicated or uninformative.
Emanuel Della-Torre, Laura Galli, Diego Franciotta, Enrica Paola Bozzolo, Chiara Briani, Roberto Furlan, Luisa Roveri, Maria Sessa, Gabriella Passerini, and Maria Grazia Sabbadini.
Università Vita-Salute San Raffaele, School of Medicine, San Raffaele Scientific Institute, via Olgettina 58, 20132, Milan, Italy; Unit of Medicine and Clinical Immunology, San Raffaele Scientific Institut... more e, via Olgettina 60, 20132, Milan, Italy. Electronic address: dellatorre.emanuel@hsr.it. less