Extranodal Rosai-Dorfman disease manifesting as Sjögren's syndrome combined with panuveitis and hypertrophic pachymeningitis: a case report and review of literature.

Rosai-Dorfman disease (RDD) is a rare non-Langerhans cell histiocytosis characterized by massive lymphadenopathy and systemic extranodal lesions. We present the case of a 28-year-old woman who presented with recurrent blurred vision in her right eye for 3 months. She developed blindness and atrophy in her left eye a decade prior to presentation. She subsequently developed headache, fever, and impaired mental status. Cranial magnetic resonance imaging indicated hypertrophic pachymeningitis (HP), and 18F-fluoro-2-deoxy-2-d-glucose (FDG) positron emission tomography/computed tomography revealed significant FDG uptake in the left dura mater. Autoimmune testing revealed elevated anti-nuclear, anti-SS-A, and anti-SS-B antibody levels. Incisional biopsy of the atrophic eyeball revealed RDD with marked polyclonal plasmacytosis. The patient was diagnosed with RDD accompanied by multisystem involvement, including Sjögren's syndrome (SS), panuveitis, and HP. Treatment with methylprednisolone for several weeks resulted in significant improvement. This is the first reported case of RDD presenting with SS in combination with panuveitis and HP. Although RDD is rarely diagnosed in young patients, interdisciplinary collaboration is essential to prevent a delayed diagnosis.

Cogan's Syndrome Combined with Hypertrophic Pachymeningitis: A Case Report.

Cogan's syndrome (CS) is a rare chronic inflammatory disease, characterized by interstitial keratitis and vestibular auditory dysfunction. Hypertrophic pachymeningitis (HP) is a rare chronic aseptic inflammatory disease of the central nervous system. This article reports a patient with CS coexisting with HP. The patient was a 66-year-old male with fever, headache, red eyes, hearing loss, and significantly elevated inflammatory markers. Cerebrospinal fluid examination, blood culture, and tests for autoantibodies such as antinuclear antibodies were negative. Pure tone audiology (PTA) indicated bilateral sensorineural deafness. Both Positron emission tomography-computed tomography (PET/CT) and vascular color Doppler ultrasound suggest the presence of vasculitis. Considering Cogan's syndrome, the patient received 40 mg of methylprednisolone intravenously once daily. The brain's magnetic resonance imaging (MRI) revealed slightly thickened and enhanced dura mater, suggesting HP. The dose of methylprednisolone was increased to 40 mg intravenously every 8 hours, leading to the patient's improved symptoms and decreased inflammatory markers. Both CS and HP are rare chronic inflammatory diseases, and their coexistence is even rarer, with only two reported cases in literature up to date. The coexistence of CS and HP should be considered when the CS patients with headaches do not respond well to treatment.

[Idiopathic hypertrophic pachymeningitis]. / Idiopaticheskii gipertroficheskii pakhimeningit.

The article presents a case of idiopathic hypertrophic pachymeningitis of a 61-year-old male patient with severe cephalgia and progressive neuropathy of the oculomotor nerves. The diagnosis was confirmed by MRI with gadolinium, which revealed thickening of the dura mater with accumulation of paramagnetic in the convexital parts of the frontal and temporal regions, as well as on the base of the skull and tentorium. During the use of pulse therapy with glucocorticosteroids (GCS) the symptoms regressed, but when the therapy was stopped, there was a relapse of ptosis and oculomotor abnormalities on the other side followed by a slower effect of GCS therapy. The article also presents a brief review of current knowledge about this pathology.

Hypertrophic Pachymeningitis: An Unusual Cause of Headache.

Hypertrophic pachymeningitis (HP) is a rare condition characterized by inflammation and thickening of the dura mater. It can be idiopathic or secondary to various causes, including infections, tumors, or systemic inflammatory diseases. Diagnosis is challenging due to its rarity and the overlap of symptoms with other conditions. We present the case of a 42-year-old Hispanic woman with diabetes mellitus type 2 and end-stage kidney disease who presented with chest pain, dry cough, mild dyspnea, and chronic occipital headaches. Physical examination revealed cranial VI nerve palsy. Imaging showed pulmonary cavitary lesions and mediastinal lymphadenopathy. Elevated inflammatory markers and positive autoimmune tests, including rheumatoid factor and antineutrophil cytoplasmic antibody (ANCA), led to further investigation. Brain imaging revealed dural thickening, confirming HP. The patient's medical history revealed double ANCA positivity and a lung biopsy confirmed granulomatous pneumonitis. A diagnosis of ANCA-associated vasculitis (granulomatosis with polyangiitis (GPA)) was established, and treatment with rituximab and high-dose corticosteroids led to symptom improvement. GPA rarely involves meningeal inflammation, but severe and persistent headaches are common early symptoms. Inflammatory markers are often elevated, and around two-thirds of HP cases related to GPA have positive serum ANCA. MRI is the primary diagnostic tool, with characteristic findings of dural thickening and contrast enhancement. This case highlights HP as a rare cause of chronic headaches and the importance of a comprehensive medical history in diagnosis. Early recognition and treatment are crucial for improving outcomes in GPA-related HP.

Hypertrophic pachymeningitis of the internal auditory canal and cerebellopontine angle from a large recurrent attic cholesteatoma.

OBJECTIVES: To describe a rare complication of cholesteatoma. METHODS: Case report with literature review. RESULTS: We report a case of a 37-year-old male who presented for evaluation of otorrhea, headache, and progressive left sensorineural hearing loss. Clinical and radiologic evaluation demonstrated a large recurrent attic cholesteatoma with erosion into the lateral and superior semicircular canals, and diffuse enhancement of the internal auditory canal and cerebellopontine angle suggestive of hypertrophic pachymeningitis secondary to cholesteatoma. After treatment with a course of antibiotics and canal wall down mastoidectomy surgery for cholesteatoma exteriorization, he experienced improvement of his symptoms and resolution of hypertrophic pachymeningitis. CONCLUSION: Hypertrophic pachymeningitis is a rarely described complication of cholesteatoma. In the context of cholesteatoma, treatment with antibiotics and surgical removal or exteriorization of cholesteatoma are effective treatments for HP.

An Incidental Finding of Idiopathic Hypertrophic Pachymeningitis: A Case Report.

In this case report, we discuss and explore the clinical, laboratory, and imaging findings, as well as the treatment options and follow-up measures, in an 83-year-old patient with idiopathic hypertrophic pachymeningitis (IHP), a rare disorder characterized by fibrosing, hypertrophic inflammation that thickens the dura mater. An 83-year-old female with a medical history of hypertension and hyperlipidemia presented with speech arrest and was taken to the emergency department, where she received a stroke code, a CT scan, and an MRI. The MRI results showed a temporal lobe meningioma and a pan-cranial pachymeningitis encasing the entire brain and cerebellum and extending into the upper cervical spine. Multiple unsuccessful attempts at a lumbar puncture were made, so a dural biopsy specimen was obtained, which revealed no malignant process. A cerebral spinal fluid specimen (CSF) from the biopsy showed minimal white blood cells (WBCs) which ruled out infection. Idiopathic hypertrophic pachymeningitis was the given diagnosis based on the apparent MRI findings. The patient was treated in the hospital for four days with IV methylprednisolone and discharged on oral methylprednisolone for four to six weeks.

Immunoglobulin G4-related hypertrophic pachymeningitis with an isolated scalp mass mimicking a brain tumor: a case report and literature review.

Immunoglobulin G4-related disease (IgG4-RD) is an autoimmune disorder associated with fibroinflammatory conditions that can affect multiple organs. Hallmark histopathological findings of IgG4-RD include lymphocytic infiltration of IgG4-positive plasma cells, storiform fibrosis, and obliterative phlebitis. However, little is known about central nervous system involvement of IgG4-RD. Hypertrophic pachymeningitis (HP) has recently been reported as a manifestation of IgG4-RD, which may have previously been demonstrated in a significant percentage of idiopathic cases. Herein, we report a rare case of a 63-year-old male who presented with a scalp mass that mimicked a brain tumor. He was diagnosed with IgG4-related HP (IgG4-RP) after surgery. This case suggests that awareness of a possibility of IgG4-RP in patients with isolated scalp masses, even in the absence of systemic symptoms, is crucial. A combination of careful history taking, evaluation of serum IgG4-levels and imaging as an initial work-up, followed by tissue biopsy, is important for the differential diagnosis of IgG4-RP, malignancy, and other infectious diseases.

The Spectrum of Intracranial Hypertrophic Pachymeningitis at an Eastern Indian Tertiary Care Center.

Introduction: Hypertrophic pachymeningitis (HP) is a treatable, rare inflammatory disease, either primary or secondary to systemic causes. Aims: To characterize the etiology, clinical manifestations, and treatment outcomes of HP patients and determine the factors influencing the radiological resolution of the pachymeningeal enhancement and recurrence of symptoms within the follow-up period. Materials and Methods: We collected data for this prospective observational study between March 1, 2021 and May 31, 2022, at the Bangur Institute of Neurosciences, Kolkata, and the patients were followed for a 6-month period. Demographic, clinical, laboratory, and treatment-related data were collected. A univariate logistic regression model was used for comparison between patients with and without radiological resolution of pachymeningitis and between patients with and without symptom recurrence. Results: Among 44 patients, the male: female ratio was 1.2:1. The median age at disease onset was 35.5 (28.5-49.5) years. The etiologies were idiopathic (56.8%), tuberculosis (22.8%), immunoglobulin G subtype 4 (IgG4) disease (9.2%), other infections (6.8%), and neoplastic (4.4%). Headache was the most common presentation (95.4%), followed by cranial neuropathies (68.2%). Optic and oculomotor neuropathies were the most common. In terms of radiological features, 27.27, 29.54, and 43.18% of patients had diffuse, focal regular, and focal irregular enhancement, respectively. Temporal (50%), followed by cavernous sinus (38.63%) enhancement, was the most common. Recurrence occurred in 36 and 50% of idiopathic and IgG4-related HP cases, respectively. Mycophenolate mofetil was added to their steroid regimen with no further recurrences. Conclusion: The cohort had a marked absence of (antineutrophil cytoplasmic antibodies) ANCA-associated HP. The severity of clinical manifestations or distribution of pachymeningitis did not differ significantly among the etiological groups. The presence of idiopathic etiology and focal regular enhancement had a significantly higher chance of radiological resolution. The response to therapy was satisfactory. Recurrence was significantly related to shorter steroid courses (

Hypertrophic Pachymeningitis as an Unusual Cause of Headache and Sphincter Dysfunction in Systemic Lupus Erythematosus.

Hypertrophic pachymeningitis (HP) is an uncommon condition characterised by focal or diffuse thickening of the dura mater. An increasing number of cases have been reported of its association with underlying connective tissue diseases. It is a rare complication in systemic lupus erythematosus (SLE) and might be the initial and sole clinical manifestation. We report a case of a 21-year-old man presenting with febrile meningeal syndrome and sphincter dysfunction. Physical examination showed malar rash and joint pain. Biological assessment revealed a regenerative normocytic normochromic anaemia, a leucopenia and a lymphopenia. The 24-hour urine protein was positive at 0.6 g. Immunological evaluation revealed positive antinuclear, anti-Sm and anti-dsDNA antibodies. Brain and spinal magnetic resonance imaging showed hypertrophic pachymeningitis. Cerebrospinal fluid biochemistry was within normal limits. Renal biopsy revealed a mesangial proliferative lupus nephritis. The diagnosis of SLE with neurologic and renal involvement was established, and the patient was treated with intravenous methylprednisolone pulse, followed by oral prednisone in association with azathioprine and hydroxychloroquine. Considering the persistence of symptoms and MRI lesions after 6 months, a treatment with rituximab was initiated with good evolution. LEARNING POINTS: Hypertrophic pachymeningitis is a rare condition of diverse aetiologies.A workup including search for infectious, autoimmune and neoplastic aetiologies should be performed.It is an extremely rare complication in systemic lupus erythematosus and might be the initial and sole clinical manifestation.

A Rare Diagnosis of Aseptic Hypertrophic Pachymeningitis: A Case of Mycobacterial Tuberculosis Origin.

Tubercular meningitis is a rare yet devastating type of extrapulmonary tuberculosis (TB) posing great diagnostic challenges due to the nonspecific clinical presentation of the patients. Here, we present a rare diagnosis of hypertrophic pachymeningitis due to Mycobacterium tuberculosis. A 36-year-old male presented with a history of headaches and giddiness for one month. Neurological examination revealed hypo-reflexive triceps and ankle reflexes. Routine blood tests and autoimmune workup were normal. Brain MRI with contrast revealed diffuse dural thickening, focal leptomeningeal enhancement in the right temporal sulci, and enhancement in both the frontal and parietal convexity and the falx cerebri and along the tentorium cerebelli. Cerebrospinal fluid (CSF) analysis revealed elevated proteins, suggestive of aseptic meningitis. Meningeal biopsy revealed a chronic ill-formed granulomatous inflammatory lesion with occasional acid-fast bacilli, consistent with tubercular pachymeningitis. The patient was administered intravenous (IV) methylprednisolone for five days, following which the symptoms subsided. He was advised tablet prednisolone on discharge, and immunomodulation with rituximab was recommended as outpatient treatment. Hypertrophic pachymeningitis is a rare diagnosis characterized by the inflammation and fibrosis of the dura matter due to a diverse etiology. Tubercular etiology must be considered when the routine laboratory tests are negative, and the diagnosis should be confirmed by meningeal biopsy. The treatment of the underlying cause and corticosteroids remain the mainstay management of hypertrophic pachymeningitis. Hence, mycobacterial tuberculosis should be considered as a possible differential diagnosis while evaluating hypertrophic pachymeningitis, especially when the routine laboratory tests and immunological workup are negative.

Quantitative evaluation of the thickened dura mater impacting clinical signs in immune-mediated hypertrophic pachymeningitis.

OBJECTIVE: This study evaluated the volume of thickened dura mater lesions and their impact on clinical findings in immune-mediated hypertrophic pachymeningitis (HP). METHODS: The volume of contrast-enhanced dura mater on magnetic resonance imaging was evaluated using the imaging feature quantification system in 19 patients with immune-mediated HP, including 12 with antineutrophil cytoplasmic antibody-related, 4 with IgG4-related, and 3 with idiopathic HP, as well as 10 with multiple sclerosis (MS) as controls. The implications of HP volume on neurological manifestations and cerebrospinal fluid (CSF) laboratory markers were statistically analyzed in patients with immune-mediated HP. RESULTS: The volumes of the contrast-enhanced dura mater in the convexity, cranial fossa, and tentorium cerebelli were significantly higher in patients with immune-mediated HP than in those with MS. Among patients with immune-mediated HP, those with cranial nerve (CN) VIII neuropathy had a significantly higher volume of the contrast-enhanced dura mater in the cranial fossa than those without CN VIII neuropathy. The volume of the contrast-enhanced dura mater in the tentorium cerebelli was positively correlated with CSF protein levels. CONCLUSION: Quantification of the thickened dura mater is useful for elucidating the relationship with the clinical findings in immune-mediated HP. Thickened dura mater lesions in the cranial fossa may be implicated in the development of CN VIII neuropathy. The enlargement of HP lesions in the tentorium cerebelli can increase CSF protein levels.

A selected case series of idiopathic hypertrophic pachymeningitis in a single center: Pathological characteristics and case-oriented review.

Hypertrophic pachymeningitis (HP) is a relatively rare disease of the central nervous system characterized by local or diffuse fibrous thickening of the dura mater. At present, there is still insufficient research on the pathogenesis and treatment strategies of this disease. We reported a continuous case series of seven patients with idiopathic HP (IHP), and also details one case of immunoglobulin G4-related HP requiring surgical intervention. Early diagnosis and appropriate surgical intervention for IHP could prevent the progression of permanent neurological damage and spinal cord paraplegia.

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)

Chronic Suppurative Otitis Media Patient Presenting With Hyperhomocysteinemia in Granulomatosis With Polyangiitis.

Granulomatosis with Polyangiitis (GPA) can present with Cerebral Venous Sinus Thrombosis (CVST), Chronic Suppurative Otitis Media, and Lower Motor Neuron (LMN) Facial Palsy. However, an association between CVST and Hyperhomocysteinemia in GPA has not previously been reported. Here, we report a case of CVST and Hyperhomocysteinemia in Proteinase 3 anti-neutrophil cytoplasmic antibody (PR3-ANCA) positive GPA without renal involvement.

Hypertrophic Pachymeningitis with Persistent Intrathecal Inflammation Secondary to Neurosarcoidosis Treated with Intraventricular Chemotherapy: A Case Report.

Hypertrophic pachymeningitis (HP) is a rare immune-mediated disease characterized by thickening of the dura mater with consecutive cranial neuropathy. While HP is usually treated with systemic immunotherapies, response to therapy is variable and may be limited by insufficient drug concentrations in the brain. We report on a 57-year-old patient with HP manifesting with vision and hearing loss who had sustained clinical progression despite various systemic immunotherapies. Intraventricular chemotherapy with methotrexate, cytarabine, and dexamethasone was initiated. We present clinical, imaging and cerebrospinal fluid (CSF) findings, including cytokine levels before and after intraventricular treatment: rapid decrease of cell count, lactate and profibrotic cytokine levels in the CSF following intraventricular chemotherapy was paralleled by a mild reduction of dura thickness in MRI. The already severely impaired visual acuity and hearing loss did not progress further. Treatment was complicated by exacerbation of previously subtle psychiatric symptoms. Follow-up was terminated after 6 months as the patient suffered from a fatal ischemic stroke. Autopsy revealed neurosarcoidosis as the underlying cause of HP. This case report suggests that intrathecal chemotherapy can reduce the inflammatory milieu in the CNS and should be considered for treatment-refractory HP before irreversible damage of cranial nerves has occurred.

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.

Hypertrophic pachymeningitis in ANCA-associated vasculitis: Clinical and immunopathological features and insights.

Hypertrophic pachymeningitis (HP) is an inflammatory disorder characterized by intracranial and spinal thickened dura mater, leading to several neurological manifestations including headaches, cranial neuropathies, seizures, and sensorimotor disorders. Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a crucial disease that is implicated in the development of immune-mediated HP. HP is observed throughout the clinical course of AAV, and 3%-4% of patients with AAV experience HP as the initial clinical episode. However, patients with ANCA-related HP are unclassifiable in the classification criteria of AAV when HP is the only manifestation, suggesting that ANCA-related HP can be identified as a central nervous system-limited type of AAV. Among patients with AAV, those who develop HP have predominantly been classified as having granulomatosis with polyangiitis (GPA). Myeloperoxidase-ANCA positivity has been more frequently demonstrated than proteinase 3-ANCA positivity in patients with ANCA-related HP. The ear, nose, and throat manifestations, such as otitis media, sinusitis, and mastoiditis, as well as mucous membranes/eyes manifestations including sudden visual loss, are robustly associated with HP in AAV. The histology of thickened dura mater tissues includes fibrotic changes and infiltration of several immunocompetent cells, but the typical findings of GPA, such as granulomatous inflammation with necrotizing vasculitis, are not observed in all patients with ANCA-related HP. Corticosteroids are the first-line therapy for ANCA-related HP, while the concomitant use of immunosuppressive agents including cyclophosphamide, methotrexate, and mycophenolate mofetil, is an ideal strategy for achieving remission. Rituximab is a useful agent in refractory ANCA-related HP.

Granulomatosis with Polyangiitis Presenting with Thrombovasculitic and Necrotizing Pachy- and Leptomeningitis Accompanied by a Brain Tumor-like Lesion.

We report a case of granulomatosis with polyangiitis (GPA) presenting with hypertrophic pachymeningitis with a huge brain tumor-like lesion. A 57-year-old man acutely developed consciousness disturbance. Magnetic resonance imaging revealed a right frontal lobe mass with thickened, contrast-enhanced dura. Computed tomography revealed sinusitis and multiple lung nodules. The presence of proteinase 3-anti-neutrophil cytoplasmic antibody indicated GPA. Histopathology of the excised brain tissues revealed thrombovasculitis with heavy neutrophilic infiltration in the pachy- and leptomeninges covering an ischemic cerebral cortex. The patient improved with corticosteroids and rituximab. Our case warrants considering GPA as a cause of hypertrophic pachymeningitis with brain-tumor like lesions.

Long-term response to immunotherapy in patients with hypertrophic pachymeningitis.

Objective: In this study, we aimed to clarify the relationship between initial treatment response, prednisolone (PSL) dosage, clinical type, and recurrence in patients with hypertrophic pachymeningitis (HP). Methods: The study cohort comprised eight patients with HP who had been admitted to our hospital from April 2015 to June 2020. Diagnostic criteria for HP included neurological abnormalities and dural thickening on magnetic resonance gadolinium-enhanced T1-weighted images. Results: Relevant characteristics of the eight study patients are as follows. There were two men and six women. The average age at onset was 58.3 (range: 29-79) years. Three of them had myeloperoxidase-antineutrophil cytoplasmic antibody-related vasculitis, one immunoglobulin G4-related disease, and one ulcerative colitis. The remaining three patients had idiopathic HP. The average maximum dosage of PSL was 0.79 mg/kg/day, and the average daily maintenance dosage 0.18 mg/kg/day. Three patients needed additional immunosuppressive drugs. Both idiopathic and secondary HP initially responded well to PSL, with improvement in activities of daily living. Six patients had some sequelae related to cranial nerve involvement. No relapses occurred while the patients were taking moderate doses of PSL; however, all patients with idiopathic HP had recurrences when their PSL dosage was reduced. Conclusions: Patients with idiopathic HP and HP associated with immune disorders respond to steroids and immunosuppressive drugs and recover well. However, there is a high rate of relapse after reduction of PSL dosage, mainly in those with idiopathic HP.