Paquimeningitis hipertrófica por enfermedad relacionada con IgG4 (ER-IgG4), reporte de un caso / Hypertrophic pachymeningitis due to IgG4-related disease (RD-IgG4). A case report

Introducción: La paquimeningitis hipertrófica (PH) es una entidad clínico-imagenológica caracterizada por un engrosamiento de la duramadre que puede ser focal o difuso manifestada por una variedad de síndromes neurológicos. Etiológicamente se clasifica en infecciosa, neoplásica, autoinmune e idiopática. Se ha demostrado que muchos de estos casos, antes idiopáticos, caen en el espectro de la enfermedad relacionada con IgG4. Objetivo: Describir el caso de una paciente asistida en nuestro servicio por compromiso neurológico por PH con diagnóstico inicial de tumor miofibroblástico inflamatorio (TMI) y diagnóstico final de enfermedad relacionada con IgG4. Caso: Mujer de 25 años con cuadro neurológico de 3 años de evolución caracterizado inicialmente por hipoacusia derecha, que evoluciona con cefalea y diplopía. Se realiza resonancia magnética nuclear (RMN) de encéfalo donde se evidencia engrosamiento paquimeníngeo con compromiso de estructuras vasculonerviosas en la punta del peñasco, seno cavernoso, agujero rasgado y quiasma óptico. Se presenta a la consulta con resultado de biopsia incisional que informa de lesión proliferativa que combina elementos fibrosos, de disposición fascicular o arremolinada con bandas colagenizadas con infiltrado linfoplasmocitario denso y algunos macrófagos, con tinción negativa para ALK 1 y con diagnóstico de tumor miofibroblástico inflamatorio. Por sospecha de enfermedad relacionada con IgG4 (ER-IgG4) se envía pieza de biopsia a revisión y se solicitan estudios complementarios pertinentes. Revisión de biopsia: fibrosis de tipo no estoriforme, infiltrado con predominio linfoplasmocitario, en otros cortes se reconocen también histiocitos y polimorfonucleares, sin granulomas ni atipias. Tinción para gérmenes negativos. Inmunohistoquímica con 50-60 células IgG4+/HPF e intervalo del 15 al 20%, CD68+ en histiocitos, CD1a− y S100...(AU)

Introduction: Hypertrophic pachymeningitis (HP) is a clinico-radiological entity characterized by a thickening of the dura mater that may be focal or diffuse and manifested by a variety of neurological syndromes. Aetiologically, it is classified as infectious, neoplastic, autoimmune, and idiopathic. Many of these formerly idiopathic cases have been shown to fall into the spectrum of IgG4-related disease. Objective: To describe the case of a patient attended for neurological involvement due to hypertrophic pachymeningitis with initial diagnosis of inflammatory myofibroblastic tumour and final diagnosis of IgG4-related disease. Case: A 25-year-old woman with neurological symptoms of 3 years’ evolution characterized initially by right hypoacusis, evolving with headache and diplopia. Magnetic resonance imaging (MRI) of the encephalon showed pachymeningeal thickening with involvement of vasculo-nervous structures in the tip of the cerebellum, cavernous sinus, ragged foramen, and optic chiasm. The patient presented for consultation with the result of an incisional biopsy that reported a proliferative lesion combining fibrous elements of fascicular or swirling arrangement with collagenized streaks with dense, lymphoplasmacytic infiltrate and some macrophages, with negative staining for ALK 1, with a diagnosis of inflammatory myofibroblastic tumour.Due to suspicion of IgG4-related disease (IgG4-RD) the biopsy was sent for review and pertinent complementary studies were requested.(AU)

Hypertrophic pachymeningitis due to IgG4-related disease (RD-IgG4). A case report.

INTRODUCTION: Hypertrophic pachymeningitis (HP) is a clinico-radiological entity characterized by a thickening of the dura mater that may be focal or diffuse and manifested by a variety of neurological syndromes. Aetiologically, it is classified as infectious, neoplastic, autoimmune, and idiopathic. Many of these formerly idiopathic cases have been shown to fall into the spectrum of IgG4-related disease. OBJECTIVE: To describe the case of a patient attended for neurological involvement due to hypertrophic pachymeningitis with initial diagnosis of inflammatory myofibroblastic tumour and final diagnosis of IgG4-related disease. CASE: A 25-year-old woman with neurological symptoms of 3 years' evolution characterized initially by right hypoacusis, evolving with headache and diplopia. Magnetic resonance imaging (MRI) of the encephalon showed pachymeningeal thickening with involvement of vasculo-nervous structures in the tip of the cerebellum, cavernous sinus, ragged foramen, and optic chiasm. The patient presented for consultation with the result of an incisional biopsy that reported a proliferative lesion combining fibrous elements of fascicular or swirling arrangement with collagenized streaks with dense, lymphoplasmacytic infiltrate and some macrophages, with negative staining for ALK 1, with a diagnosis of inflammatory myofibroblastic tumour. Due to suspicion of IgG4-related disease (IgG4-RD) the biopsy was sent for review and pertinent complementary studies were requested. BIOPSY REVIEW: Non storiform fibrosis, predominantly lymphoplasmacytic infiltrate, histiocytes, and polymorphonuclear infiltrate in sectors, without granulomas or atypia. Staining for germs negative. Immunohistochemistry with 50-60 IgG4+/HPF cells and range of 15%-20%, CD68+ in histiocytes, CD1a-, S100-. The patient presented deterioration of visual acuity due to ophthalmic nerve involvement, so glucocorticoid treatment was started in pulses and rituximab with regression of symptoms and imaging improvement of the lesions. CONCLUSION: HP is a clinical imaging syndrome with variable symptoms and aetiologies that poses a diagnostic challenge. In this case the initial diagnosis was inflammatory myofibroblastic tumour, which is a neoplasm of variable behaviour, locally aggressive, and can metastasize; it is one of the main differential diagnoses of IgG4-related disease because they share anatomopathological features, including storiform fibrosis. IgG4-RD is an immune-mediated condition that can have single or multiple involvement. Its diagnosis is complex when it presents with single organ involvement or in non-typical organs (CNS, meninges) in which data are scarce, as in the case of our patient with single organ involvement of the CNS. Although there are classification criteria to guide non-specialists in the diagnosis, the sum of the clinical picture, imaging, laboratory, pathological anatomy, and immunohistochemistry will always be evaluated together for a definitive diagnosis.