CHRONIC HYPERTROPHIC PACHYMENINGITIS IN A SHUNTED PATIENT. ¿CAUSE OR COINCIDENCE?

Abstract

Introduction: Chronic hypertrophic pachymeningitis (HCP) is an inflammatory disease characterized by diffuse thickening of the cranial or spinal dura mater. It is related to various inflammatory, autoimmune or infectious conditions. The diagnosis of the idiopathic pachymeningitis is usually made by exclusion, even though recently it has been related to the IgG4 deposition disease. This condition produces a refractory headache, occasionally associated with cranial nerves involvement, increased intracranial pressure, high CSF protein concentration or pleocytosis. To confirm the diagnosis of HCP, granulomatous and autoimmune diseases have to be discarded and a meningeal biopsy with compatible findings is required. In patients with a history of ventricle peritoneal shunt, the diagnosis can be challenging because the findings in neuroimaging are similar to the intracranial hypotension syndrome. Case report: We present a 46 years old woman shunted due to a benign intracranial hypertension who presented years later a refractory headache, raised ICP and neurological deficit in cranial nerves. Despite several surgeries to check the shunt, the patient only responded to corticosteroids. The MRI showed lineal meningeal enhancement and the meningeal biopsy lymphoplasmacytic cell infiltration and fibrous tissue hyperplasia. After the diagnosis of HCP, she was treated with daily metilprednisolone. Currently she is stable, with cranial nerves deficits and daily headache. Conclusions:  HCP and intracranial hypotension syndrome have similar neuroimaging so in a patient with a ventricle peritoneal shunt, the diagnosis can be challenging. A secondary HCP can´t be ruled out.