Fig. 2

Immunoglobulin staining of control patients, control meningitis patients and DCT patients. a–c A non-meningitis control case without immunoglobulin deposition. IgA (a), IgG (b) and IgM (c). d–f A non-meningitis control case with deposition of IgG (e). No IgA (d) and IgM (f) deposition is seen. g–i A non-meningitis control case with deposition of IgA (g), IgG (h) and IgM (i). IgG is also deposited in tunica media (arrow). j–l Representative image of immune globulin deposition in both DCT and control meningitis cases. IgG (k) and IgM (l) deposition can be seen in all three arterial layers. There was stronger IgM stain observed than IgG. IgA (j) was in most cases absent. m–o Immunoglobulin deposition in artery without inflammation. IgG (n) and IgM (o) were seen in all three arterial layers including media of a non-DCT meningitis case (arrows). Little IgA (m) was observed only in tunica adventitia (arrow head)