PT  - JOURNAL ARTICLE
AU  - Levraut, Michaël
AU  - Cohen, Mikaël
AU  - Bresch, Saskia
AU  - Giordana, Caroline
AU  - Burel-Vandenbos, Fanny
AU  - Mondot, Lydiane
AU  - Sedat, Jacques
AU  - Fontaine, Denys
AU  - Bourg, Véronique
AU  - Martis, Nihal
AU  - Lebrun-Frenay, Christine
TI  - Immunoglobulin G4-related hypertrophic pachymeningitis
AID  - 10.1212/NXI.0000000000000568
DP  - 2019 Jul 01
TA  - Neurology - Neuroimmunology Neuroinflammation
PG  - e568
VI  - 6
IP  - 4
4099  - http://nn.neurology.org/content/6/4/e568.short
4100  - http://nn.neurology.org/content/6/4/e568.full
SO  - Neurol Neuroimmunol Neuroinflamm2019 Jul 01; 6
AB  - Objective Meningeal involvement in Immunoglobulin G (IgG)-4-related disease is rare and only described in case reports and series. Because a review into the disease is lacking, we present 2 cases followed by a literature review of IgG4-related hypertrophic pachymeningitis (IgG4-HP).Methods Two IgG4-HP cases were reported, one involving the spinal cord and responding to surgical management and a second involving the brain and responding to Rituximab therapy. We then review clinical cases and case-series of histologically proven IgG4-HP that were published in the PubMed-NCBI database.Results Forty-two case reports and 5 case-series were studied (60 patients, 20 women). The median age was 53. Eighteen patients had systemic involvement and 24 had single-organ IgG4-HP. Fifty-five percent of patients had an elevated serum IgG4. Treatment was surgical in 20/53 cases. Steroid therapy and immunosuppressors were effective in 85% and more than 90% of the cases, respectively. The rate of disease relapse was 42.1% after steroid therapy was discontinued.Discussion/conclusion IgG4-HP is characterized by the lack of extra-neurologic organ-involvement and systemic signs. Histopathologic studies should be performed as it is crucial for diagnosis because serum markers are rarely informative. 18F-FDG positon tomography can be useful to characterize systemic forms. There is no specific CSF marker for IgG4-HP and the diagnostic value of CSF IgG4 levels needs to be studied with larger samples. We provide a treatment algorithm for IgG4-HP. Such treatment strategies rely on early surgery, steroids, and early immunosuppressive therapy to prevent neurologic complications.CYC=cyclophosphamide; GPA=granulomatosis with polyangeitis; HPF=high-power field; IgG4=immunoglobulin G4; IgG4-HP=IgG 4-related hypertrophic pachymeningitis; IgG4-RD=IgG 4-related disease; RI=Responder Index; RTX=Rituximab; WBC=white blood cell