Imaging features, clinicopathological analysis and diagnostic strategy of IgG4-related hypertrophic pachymeningitis

This study was conducted to summarize the clinical, magnetic resonance imaging (MRI) and pathological features of IgG4-realated hypertrophic pachymeningitis (IgG4-RHP) and its differential diagnosis from similar diseases.

Data of IgG4-RHP patients admitted to Department of Neurology, Neurosurgery and Infection, the First Affiliated Hospital of Medical School of Zhejiang University from January 1, 2015 to July 31, 2019 were collected and their clinical symptoms, laboratory examinations, imaging and pathological features were investigated. At the same time, the clinicopathological and imaging findings of other dura thickening diseases diagnosed in our hospital were compared and analyzed.

The clinical symptoms of 4 IgG4-RHP patients include chronic headache and cranial nerves injury, etc. Levels of serum IgG4 and cerebrospinal fluid (CSF) IgG4 increased in all patients. Focal enhancement of dura mater could be seen on plain and enhanced cranial MRI. Pathological results were consistent with IgG4-RHP symptoms. Among other diseases that cause dural thickening, the content of serum C-reactive protein in patients with Rosai-Dorfman disease declined. Patients with intracranial hypotension syndrome often have postural headache. Patients with tuberculous meningitis can have previous pulmonary tuberculosis. The diagnosis of patients with atypical meningioma depends on the results of operation and pathology. Patients with central nervous system leukemia can be diagnosed with reference to the results of laboratory results.

The clinicopathological and imaging manifestations of IgG4-RHP are summarized in this study. Meanwhile, the clinical data of several other diseases with similar imaging characteristics are analyzed in order to clarify the diagnostic strategy of IgG4-RHP and provide help for the next treatment.