Background Idiopathic hypertrophic pachymeningitis (IHP) is a rare chronic inflammatory disease characterized by fibrous thickening of the cerebral and/or spinal dura matter, with a clinical presentation depending on the topography of the dural thickening. Prevalence of IHP is not known due to its rarity. Case series come mainly from Asian countries and only a handful of case reports from Latin American countries can be found in the literature.
Objectives We aimed to elucidate the clinical, laboratory, and radiological features, treatment and outcome of a cohort of Mexican patients with IHP.
Methods Consecutive patients with the final diagnosis of IHP seen between November 2002 and January 2016 at Hospital Civil de Guadalajara “Fray Antonio Alcalde”, a tertiary referral center in western Mexico, were included. Known causes of secondary hypertrophic pachymeningitis were ruled out. All patients gave informed consent to be included in this study. We analyzed demographic, clinical, laboratory, neuroimaging and therapeutic data.
Results Five patients were included (1 male and 4 female). Mean age of beginning of symptoms was 32.2 years (range: 13–59); mean age at diagnosis of IHP was 36.8 years (range: 20–63); mean duration of symptoms before diagnosis was 55.4 months (range 2–132). All patients presented with headache and visual complaints. One presented with ataxia and 2 with encephalopathy. Main cranial nerve (CN) affected was CN II (4/5, 80%), followed by CN IV, CN VI and CN VII (3/5, 60% each). Multiple cranial neuropathy was the presentation in 4 patients (4/5, 80%). One patient presented with bilateral proptosis and one patient with the Tolosa-Hunt syndrome. Mean C-reactive protein (CRP) level of 4.05 mg/dl (N= <0.80) (range: 0.78–6.63). Mean erythrocyte sedimentation rate (ESR) was 77 mm/hr (N= <10) (range: 35–109). Mean CSF cell count was 58 cells/ml (range: 2–169) and mean CSF protein was 98 mg/dl (range: 25–254). Contrast-enhanced brain MRI showed diffuse dural thickening in 4 patients and focal in one; other MRI findings were: cavernous sinus involvement (1), hypophysitis (1), orbital pseudotumor (1), pansinusitis (1), cerebral edema (3), involvement of internal auditory canals and optic canals (1). Biopsy of orbital pseudotumor was performed in one patient showing non-specific chronic inflammation. Corticosteroids were used in 4 patients. Other immunosuppressants were used as corticosteroid-sparing agents, mainly methotrexate (MTX) (4/5 patients). Mean duration of follow-up was 18.4 months (range: 2–38). Mean pre-treatment clinical score was 8.2 (range: 5–10) and mean post-treatment clinical score was 2.6 (range: 0–5).
Conclusions IHP in Mexican patients seem to occur more commonly in female patients and at a younger age compare to other populations. Main symptoms were headache and multiple cranial neuropathies and main CN affected was CN II, consistent with other series. Corticosteroids and MTX were used successfully as first line treatment with an evident decline in the HP clinical score. IHP should be consider in the differential diagnosis of headache associated with visual complaints, even in younger patients.
Acknowledgement No acknowledgements to report.
Disclosure of Interest None declared