Neurological Manifestations of IgG4-Related Disease

A 79-Year-Old Woman With Worsening Headaches and Pachymeningeal Enhancement: A Case Report From the National Multiple Sclerosis Society Case Conference Proceedings

A 79-year-old woman presented with subacutely worsening headaches and right arm weakness. MRI showed diffuse pachymeningeal enhancement. Serologic workup revealed elevated erythrocyte sedimentation rate and C-reactive protein. CSF demonstrated elevated opening pressure, a lymphocytic pleocytosis, and elevated protein. We discuss our differential diagnosis and distinguish between 2 overlapping clinical entities.

IgG4-related disease in the nervous system

IgG4-related disease (IgG4-RD) is a recently described multisystemic disorder with a spectrum of manifestations that continue to be described. Nonetheless, there are recognised distinct patterns of disease. Neurological involvement is rare, particularly in isolation, but IgG4-RD may present with orbital disease, hypophysitis or pachymeningitis. Typically, it is highly responsive to treatment. This review highlights neurological manifestations of IgG4-RD and emphasises the importance of a high index of clinical suspicion to facilitate investigation and appropriate management, avoiding irreversible tissue damage and neurological dysfunction. We present a treatment algorithm for suggested management of IgG4-RD affecting the nervous system.

A framework for exclusion of alternative diagnoses in sarcoidosis

Sarcoidosis is a multisystem granulomatous syndrome that arises from a persistent immune response to a triggering antigen(s). There is no "gold standard" test or algorithm for the diagnosis of sarcoidosis, making the diagnosis one of exclusion. The presentation of the disease varies substantially between individuals, in both the number of organs involved, and the manifestations seen in individual organs. These qualities dictate that health care providers diagnosing sarcoidosis must consider a wide range of possible alternative diagnoses, from across a range of presentations and medical specialties (infectious, inflammatory, cardiac, neurologic). Current guideline-based diagnosis of sarcoidosis recommends fulfillment of three criteria: 1) compatible clinical presentation and/or imaging 2) demonstration of granulomatous inflammation by biopsy (when possible) and, 3) exclusion of alternative causes, but do not provide guidance on standardized strategies for exclusion of alternative diagnoses. In this review, we provide a summary of the most common differential diagnoses for sarcoidosis involvement of lung, eye, skin, central nervous system, heart, liver, and kidney. We then propose a framework for testing to exclude alternative diagnoses based on pretest probability of sarcoidosis, defined as high (typical findings with sarcoidosis involvement confirmed in another organ), moderate (typical findings in a single organ), or low (atypical/findings suggesting of an alternative diagnosis). This work highlights the need for informed and careful exclusion of alternative diagnoses in sarcoidosis.

IgG4-Related Disease of Mastoid Presenting as Headache: A Case Report

IgG4-related disease (IgG4-RD) is a complex multi-system inflammatory disorder that can affect various organs in the body. This condition is characterized by elevated levels of immunoglobulin G subclass 4 (IgG4) and the presence of specific histopathological features. While neurological involvement is not as common as in other organs, when it occurs, it can lead to hypertrophic pachymeningitis and hypophysitis. Here, we present a case of a 53-year-old male with right-sided hemicranial headache and diplopia. Computed tomography revealed a soft tissue density lesion in the middle ear cavity and mastoid antrum with the destruction of the mastoid septae. Magnetic resonance imaging revealed a lesion in the right middle ear cavity associated with pachymeningitis and right sigmoid and transverse sinus thrombosis. Tissue pathology revealed dense plasma cell-rich chronic inflammation with storiform fibrosis. Immunohistochemistry was positive for IgG4. Hence, a diagnosis of IgG4-related disease causing mastoiditis, pachymeningitis and cerebral venous thrombosis was made. The patient was successfully operated and treated with steroids. IgG4-RD remains a rare but serious condition. It is crucial to identify and treat this condition promptly as it can lead to permanent organ damage. When patients continue to experience middle ear symptoms after an infection has been treated and cancer has been ruled out, it is important to consider inflammatory conditions as a differential diagnosis.

Lateral micro-orbitotomy as the technique of choice for orbital pseudotumor in IgG4-RD. Case report and review of the literature

Immunoglobulin G4-related disease (IgG4-RD) is characterized by a systemic fibroinflammatory infiltrate that often involves the orbit in addition to other tissues. Thus it has to be considered in the differential diagnosis of orbital tumors. We report the clinical case of a 64-year-old woman who presented with right mydriasis, progressive proptosis and paralysis of the third cranial nerve of 1 year of evolution. Cranial MRI identified an intraconal lesion of the right orbit, located between the external and inferior rectus muscles and the optic nerve, and she was scheduled for surgery by transcranial approach with lateral micro-orbitomy. A satisfactory macroscopic excision was achieved with no remarkable complications and a definitive deferred histological result of pseudotumor by IgG4-RD. Follow-up for 24 months showed no tumor recurrence, and the patient clinically improved from ophthalmoplegia. This case highlights the efficacy of lateral orbitotomy in the etiologic diagnosis and successful therapeutic outcome of complex orbital lesions associated with IgG4-RD pseudotumor.

Neurological Involvement in a Portuguese Cohort of IgG4-Related Disease

INTRODUCTION

Neurological involvement in immunoglobulin G4-related disease (IgG4-RD) is increasingly recognized. Its diagnosis can be challenging due to clinical mimics and difficulty in obtaining nervous system biopsies. The aim of this study was to describe a cohort of neurological IgG4-RD patients.

METHODS

Patients were recruited from a neuroimmunology tertiary center. Clinical, laboratory, neuroimaging and histological data were reviewed.

RESULTS

Fifteen patients (60% women), with a median age of 53 years (48.5 - 65.0) were included: 13 (86.7%) classified as possible IgG4-RD, one (6.7%) as probable and one (6.7%) as definitive. The most common neurological phenotypes were meningoencephalitis (26.7%), orbital pseudotumor (13.3%), cranial neuropathies (13.3%), peripheral neuropathy (13.3%), and longitudinally extensive transverse myelitis (LTEM) (13.3%). Median serum IgG4 concentration was 191.5 (145.0 - 212.0) mg/dL. Seven in 14 patients had CSF pleocytosis (50.0%) and oligoclonal bands restricted to the intrathecal compartment, while most cases presented elevated CSF proteins (64.3%). Magnetic resonance imaging abnormalities included white matter lesions in four (26.7%), hypertrophic pachymeningitis in two (13.3%), and LETM in two (13.3%). Two patients had biopsy-proven IgG4-RD in extra-neurological sites.

CONCLUSION

This study highlights the phenotypical variability of the neurological IgG4-RD. Biopsy inaccessibility reinforces the importance of new criteria for the diagnosis of this subset of patients.

Neurosurgical Intervention for Nerve and Muscle Biopsies

(1) Background: Neurologic and musculoskeletal diseases represent a considerable portion of the underlying etiologies responsible for the widely prevalent symptoms of pain, weakness, numbness, and paresthesia. Because of the subjective and often nonspecific nature of these symptoms, different diagnostic modalities have been explored and utilized. (2) Methods: Literature review. (3) Results: Nerve and muscle biopsy remains the gold standard for diagnosing many of the responsible neurological and musculoskeletal conditions. However, the need for invasive tissue sampling is diminishing as more investigations explore alternative diagnostic modalities. Because of this, it is important to explore the current role of neurosurgical intervention for nerve and muscle biopsies and its current relevance in the diagnostic landscape of neurological and musculoskeletal disorders. With consideration of the role of nerve and muscle biopsy, it is also important to explore innovations and emerging techniques for conducting these procedures. This review explores the indications and emerging techniques for neurological intervention for nerve and muscle biopsies. (4) Conclusions: The role of neurosurgical intervention for nerve and muscle biopsy remains relevant in diagnosing many neurological and musculoskeletal disorders. Biopsy is especially relevant as a supportive point of evidence for diagnosis in atypical cases. Additionally, emerging techniques have been explored to guide diagnostics and biopsy, conduct less invasive biopsies, and reduce risks of worsening neurologic function and other symptoms secondary to biopsy.

A case report of Immunoglobulin-G4-related hypertrophic sclerosing pachymeningitis

IgG4-related diseases (IgG4-RD) are a group of chronic progressive autoimmune diseases of unknown etiology that are increasingly recognized as an important pathophysiological basis for a variety of systemic diseases. It is thought to involve almost any organ of the body, but the involvement of the central nervous system is relatively rare. We report the case of a 56-year-old male patient admitted to the hospital d recurrent dizziness and nausea for more than 3 months. The preoperative imaging was misdiagnosed as a meningioma, with this lesion demonstrated localized inhomogeneous thickening of the meninges in the left parietal region on T2-weighted and T2 fat suppression sequences with localized nodular changes. The patient's final pathologic diagnosis was IgG4-associated sclerosing thick encephalitis. The diagnosis of IgG4-associated hypertrophic pontine meningitis is challenging. Clinically, IgG4-associated sclerosing diseases usually present as mass-like lesions, which can be easily misdiagnosed as neoplastic lesions due to their similar appearance. These fundamentally recognized autoimmune disorders respond well to corticosteroid therapy. Therefore, accurate detection of IgG4-related disease is critical to prevent patients from undergoing unnecessary surgery.

IgG4 disease with multiorgan involvement: a case report

BACKGROUND

IgG4-related disease (IgG4RD) is a rare fibroinflammatory disease with multiorgan involvement. It presents insidiously over several years and can be a diagnostic enigma. Delays in diagnosis occur due to failure to consider IgG4 as a differential diagnosis, atypical presentations, and an insidious clinical course.

CASE PRESENTATION

We report the case of a 70-year-old Sri Lankan man with pulmonary, renal, and neurological involvement of IgG4-related disease. Clinical manifestations evolved over a 4-year period and included exertional shortness of breath and dysesthesia of extremities. The diagnosis was established with clinical, radiological, and pathological criteria laid down by The American College of Rheumatology/European League Against Rheumatism in 2019. Following diagnosis, the patient was started on oral steroids, with rapid improvement of his respiratory and neurological symptoms. He is currently under follow-up and will be monitored with clinical and radiological parameters, complement levels, and lung function tests.

CONCLUSION

This case outlines the presentation of a patient with IgG4-related disease with concurrent involvement of three uncommon sites. It highlights methods of diagnostic deduction by considering the clinical course of illness, imaging, and histopathology. It also describes evolving associations of IgG4-related disease with tuberculosis and lymphomas, which bear important diagnostic and therapeutic considerations.

IgG4-Related Neurological Disease: A Single Center Ambispective Study from South India

IgG4-related disease (IgG4-RD) is an immune-mediated multi-system disorder. The nervous system (IgG4-RND) is rarely affected. We describe a short case series. We performed an ambispective analysis of IgG4-RND patients admitted at our centre between January 2016 and December 2022. Eight patients (M: F-2:6) were included with a mean age at presentation of 40.63 ± 17.88 years and disease duration of 5.16 ± 4.08 years. The common diseased sites were pachymeninges (7), orbits (4), paranasal sinuses (3), frontal lobe (1), hypophysis (1), leptomeninges (1), and middle ear (1). Common symptoms were headache and cranial neuropathy. The common nerves involved were the optic nerve, followed by the third, fifth, sixth, and seventh. Cerebrospinal fluid showed lymphocytic pleocytosis. Histopathology showed lymphoplasmacytic infiltrate (8), fibrosis (5), >10 IgG4 + cells (7), and IgG4/IgG >40% (6). Six had a relapsing course. The rituximab-based treatment regimen showed a favourable response.

Intracranial inflammatory pseudotumour related to IgG4: A very rare case

Background

Intracranial inflammatory pseudotumours (IPT) are rare entities that frequently lead to misdiagnosis with malignant lesions. The identification of these lesions is difficult, but important to avoid inadvertent iatrogenicity and to adjust therapeutic protocols.

Case Presentation

We report the case of a 30-year-old man who presented a single tonic-clonic seizure. Brain imaging showed a right frontal lesion with intra and extra axial components. Facing the radiologic presentation, a brain tumor was suspected, thus the patient underwent surgery. Pathological exam concluded to a plasma cell granuloma. A whole-body CT-scan showed only a thoracic aortitis. Complete blood work studies came back negative. The patient was also tested for an array of antibodies among which antinuclear antibodies were positive (blood level superior to 1/100). CSF evaluation revealed clear fluid with normal glucose concentration, normal protein levels and lymphocytic pleocytosis. Finally, IgG-4 plasma levels were elevated which led to the diagnosis of an IgG4-RD. The patient was put under prednisolone with a favorable outcome.

Conclusion

IPT have several etiologies, among which IgG4 related disease may be one of the less known as only 2 cases have previously been reported. Herein, we report a new case of a young man who presented for seizures related to an intracranial lesion of an IgG4 related disease. The challenge is to suspect such conditions to avoid unnecessary surgeries.

Giant skull base mass need not be a tumor - a rare presentation of IgG4-related disease

BACKGROUND

Giant intracranial 'IgG4-related' lesions are uncommon. They may present as pachymeningitis or localized mass. Here we report, probably, the largest IgG4 skull base mass ever to be reported.

CASE

A 40-year male presented with headache, diplopia, right-sided sensori-neuronal hearing loss, and left spastic hemiparesis. Magnetic resonance imaging showed a lesion of 8.5 cm extending from the paranasal sinuses to the right petroclival region with uniform contrast enhancement and T2 hypointensity. Endonasal biopsy revealed respiratory epithelium with fibrosis, and lymphoplasmacytic infiltrate having IgG4 positive cells >30/HPF suggestive of 'IgG4-related' disease. Serum IgG4 was within normal levels. With oral prednisolone 60 mg given daily for 6 weeks and then tapered off over 8 weeks, he improved symptomatically.

CONCLUSION

Though rare, 'IgG4-related' disease can also present as a giant skull base mass and should be kept as a differential to fungal granulomas and meningiomas. As they improve dramatically with medical management, extensive skull base resection should not be planned before obtaining a tissue biopsy, especially when there is extension into paranasal sinuses and T2 hypointensity.

Differential Diagnosis of Tumor-like Brain Lesions

Purpose of Review

Tumor-like brain lesions are rare and commonly suggest a neoplastic etiology. Failure to rapidly identify non-neoplastic causes can lead to increased morbidity and mortality. In this review, we describe 10 patients who presented with atypical, non-neoplastic tumor-like brain lesions in which brain biopsy was essential for a correct diagnosis and treatment.

Recent Findings

There has been increasing recognition of autoimmune conditions affecting the nervous system, and many of those diseases can cause tumor-like brain lesions. Currently available reports of non-neoplastic tumor-like brain lesions are scarce. Most case series focus on tumefactive demyelinating lesions, and a comprehensive review including other neuroimmunological conditions such as CNS vasculitis, neurosarcoidosis, histiocytic and infectious etiologies is lacking.

Summary

We review the literature on tumor-like brain lesions intending to increase the awareness and differential diagnosis of non-neoplastic brain tumor mimics. We advocate for earlier brain biopsies, which, in our case series, significantly changed diagnosis, management, and outcomes.

IgG4-related pachymeningitis-Long term follow up and outcome of six patients

OBJECTIVE

Our understanding of IgG4-RD and pachymeningitis has grown substantially, but the optimal approach for diagnosis, management, and long-term outcomes is still an area of uncertainty.

METHODS

HUVAC is a database for IgG4-RD patients, this database was retrospectively evaluated for pachymeningeal disease. Demographic, clinical, serological, imaging, histopathological data, and treatment details were re-interpreted in patients with pachymeningitis.

RESULTS

Among 97 patients with IgG4-RD, 6 (6.2%) had pachymeningitis. None of these patients had extracranial features, and also, in most of the patients, serum IgG4 levels were normal. Tentorium cerebelli and transverse sinus dura were the most commonly involved in the posterior fossa. During 18 months of median follow-up on steroid+-rituximab, none of them relapsed as pachymeningitis.

CONCLUSION

Our patients were mainly older males with sole neurological involvement. Non-specific headache was the most common manifestation, and serum IgG4 levels were not useful for diagnosis. Typical radiology and tentorial thickening should suggest IgG4-RD and prompt an early biopsy. Moreover, accompanying hypophysitis could also be a clue. With steroids+ rituximab treatment, no relapse related to meningeal involvement was seen in long-term follow-up.

Translation, cross-cultural adaptation, and validation of a Latin American Spanish version of the ID Migraine screening test

OBJECTIVE

To translate, culturally adapt, and validate a version of the ID Migraine into Latin American Spanish.

BACKGROUND

Although still considered a common diagnosis, half of the patients with migraine in Latin America experience diagnostic delay. The ID Migraine is a test developed in 2003 as a valuable tool for the early diagnosis of migraine at the primary care level; however, there is no validated Spanish or culturally adapted version for the Spanish-speaking population.

METHODS

This is an analytical, translation, and test-validation study. We performed back translation and cross-cultural adaptation. The Latin American Spanish version ID Migraine MX was applied to headache clinic patients from March 2021 to January 2022 to perform a validation process against the gold standard: blinded expert diagnosis according to the International Classification of Headache Disorders, 3rd edition (ICHD-3), criteria.

RESULTS

One hundred seventeen patients from the headache clinic of the National Institute of Neurology and Neurosurgery of Mexico City were screened. We found 62/117 (53%) patients positive for screening with ID Migraine MX, and 47/117 (40%) positive for migraine according to ICHD-3 criteria. A sensitivity (95% CI) of 0.91 (0.80-0.97), specificity of 0.73 (0.61-0.82), positive predictive value of 0.694 (0.57-0.794), and negative predictive value of 0.93 (0.83-0.97) were obtained. The positive likelihood ratio was 3.38 (2.27-4.99), and the negative likelihood ratio was 0.12 (0.04-0.30). After calling the patients 1 month after the first interview, the calculated Kappa test-retest was 0.75 (p = 0.001).

CONCLUSION

A translated and cross-culturally adapted version into Spanish of the ID Migraine was obtained, with a diagnostic performance similar to the original instrument. Clinicians may use this test at the first level of care to reduce the rate of misdiagnosis and the time from onset of symptoms to diagnosis and treatment of migraine.

Neurosarcoidosis: Diagnostic Challenges and Mimics A Review

PURPOSE OF REVIEW

Neurosarcoidosis is a rare manifestation of sarcoidosis that is challenging to diagnose. Biopsy confirmation of granulomas is not sufficient, as other granulomatous diseases can present similarly. This review is intended to guide the clinician in identifying key conditions to exclude prior to concluding a diagnosis of neurosarcoidosis.

RECENT FINDINGS

Although new biomarkers are being studied, there are no reliable tests for neurosarcoidosis. Advances in serum testing and imaging have improved the diagnosis for key mimics of neurosarcoidosis in certain clinical scenarios, but biopsy remains an important method of differentiation. Key mimics of neurosarcoidosis in all cases include infections (tuberculosis, fungal), autoimmune disease (vasculitis, IgG4-related disease), and lymphoma. As neurosarcoidosis can affect any part of the nervous system, patients should have a unique differential diagnosis tailored to their clinical presentation. Although biopsy can assist with excluding mimics, diagnosis is ultimately clinical.

Epiduritis related to IgG4 disease: A very rare cause for spinal cord compression

Background

Inflammatory pseudotumors are rare, and those attributed to immunoglobulin G4 (IgG4) diseases are even less frequently encountered. Here, we reviewed 41 cases from the literature of spinal inflammatory pseudotumors due to IgG4 and have added our single new case.

Case Presentation

A 25-year-old male presented with progressive back pain, bilateral paraparesis, and sphincter dysfunction. His deficit was attributed to MR-documented posterolateral lesion between the T5 and T10 levels for which he levels underwent a T1-T1010 laminectomy. The pathology revealed an immunoglobulin G4-related inflammatory pseudotumor. Postoperatively, the patient additionally required systemic and epidural administration of glucocorticoids.

Conclusion

IgG4-related disease is an emerging clinical condition that rarely involves the central nervous system. Spinal inflammatory pseudotumors, including IgG4 disease, should be more commonly considered among the potential differential diagnoses of lesions compressing the spinal cord.

Case report: Clinical highlights and radiological classification of IgG4-related spinal pachymeningitis: A rare case series and updated review of the literature

Purpose

Hypertrophic pachymeningitis associated with immunoglobulin G4-related disease (IgG4-RD) has been rarely reported, and there is little information and no clear consensus on the management of IgG4-related spinal pachymeningitis (IgG4-RSP). The present study described its possible clinical features, including the symptoms, imaging, treatment and prognosis of patients with IgG4-RSP.

Methods

We report three patients who presented with progressive neurological dysfunction due to spinal cord compression. Relevant articles were searched from the PubMed, Web of Science, and Embase databases, and the resulting literature was reviewed.

Results

The literature review provided a summary of 45 available cases, which included three cases from our center. Progressive worsening of neurological impairment was observed in 22 patients (48.9%). The lesions involved the thoracic spine (n=28, 62.2%), cervical spine (n=26, 57.8%), lumbar spine (n=9, 20.0%), and sacral spine (n=1, 2.2%). Furthermore, the lesions were located in the dura mater (n=18, 40.0%), epidural space (n=17, 37.8%), intradural-extramedullary space (n=9, 20.0%), and intramedullary space (n=1, 2.2%). On magnetic resonance imaging (MRI), the lesions generally appeared as striated, fusiform, or less often lobulated oval changes, with homogeneous (n=17,44.7%) and dorsal (n=15,39.5%) patterns being the most common. Thirty-five patients had homogeneous T1 gadolinium enhancement. Early surgical decompression, corticosteroid treatment, and steroid-sparing agents offered significant therapeutic advantages. A good therapeutic response to disease recurrence was observed with the medication.

Conclusion

The number of reported cases of IgG4-RSP remains limited, and patients often have progressive worsening of their neurological symptoms. The features of masses identified on the MRI should be considered. The prognosis was better with decompression surgery combined with immunosuppressive therapy. Long-term corticosteroid treatment and steroid-sparing agent maintenance therapy should be ensured. A systemic examination is recommended to identify the presence of other pathologies.

A rare lymphoplasmacyte-rich meningioma involving the dura of the skull base and cervical spinal cord: A case report

Lymphoplasmacyte-rich meningioma (LPRM) is a rare subtype of meningioma, the specific pathogenesis of which remains unclear. Herein, we report the case of a 48-year-old Asian man who experienced progressive deafness and limb weakness. Magnetic resonance imaging revealed extramedullary masses diffusely growing, wrapping, and compressing the cervical spinal cord. The dural lesion was partially excised by surgery, and postoperative pathological examination confirmed the diagnosis of LPRM. Diffuse LPRM is extremely rare, and its treatment is challenging owing to difficulties associated with surgery and the uncertain efficacy of traditional therapies. Therefore, further clinical practice and basic research are needed to improve the prognosis of diffuse LPRM.

IgG4-related brain pseudotumor mimicking CNS lymphoma. A case report

Here, we report a case of IgG4-related brain pseudotumor (IgG4-BP) in a 39-year-old woman, mimicking central nervous system (CNS) lymphoma. She presented with headache, fever, and fatigue. Her medical history was notable for appearance of a tumefactive brain lesion seven years before. Brain biopsy performed at the age of 32 revealed nonspecific inflammatory changes, and her condition improved with oral low-dose steroid therapy. Magnetic resonance imaging performed at the age of 39 identified a hyperintensity lesion with edema located at the medial temporal lobe region adjacent to the inferior horn of the left lateral ventricle on fluid-attenuated inversion recovery images, which showed gadolinium-contrast enhancement on T1-weighted images and a slightly hyperintensity signal on diffusion-weighted images. Methionine-positron emission tomography (PET) depicted a high methionine uptake in the lesion. Additionally, soluble levels of interleukin (IL)-2 receptor (sIL-2R) and IL-10 were increased in cerebrospinal fluid (CSF). Based on these findings, we suspected CNS lymphoma and performed partial resection of the brain lesion. Pathological examination revealed prominent lymphocytic infiltration associated with plasma cell infiltration. Most of the plasma cells were immunoreactive for IgG4. Storiform fibrosis and partially obliterative phlebitis were concomitantly observed. Thus, the patient was diagnosed as having IgG4-BP. To the best of our knowledge, this is the first case report of IgG4-BP with detailed findings obtained by CSF testing, methionine-PET, and pathological examination. Because IgG4-related diseases can present as a pseudotumor that mimics CNS lymphoma, it is essential to carefully differentiate IgG4-BP from CNS lymphoma.

A unique presentation of IgG4 disease with ocular, neurologic and mastoid involvement

A man in his 20s presented with headache and acute deterioration in visual acuity. He was found to have panuveitis and raised intracranial pressure with papilloedema. MRI and F-fluorodeoxyglucose positron emission tomography confirmed a subclinical, but active, inflammatory mastoid process. Histology of the mastoid showed immunoglobulin G4 (IgG4) cells, plasma cells and storiform fibrosis.This presentation of IgG4 disease has not been previously described.Treatment with high-dose steroids was initiated, followed by long-term immunosuppressive therapy. The patient's symptoms improved, although he remains dependent on azathioprine and low dose oral steroids for symptom control. To date, there has been no progression of the disease.

Imaging findings of immunoglobin G4-related hypophysitis: A case report

BACKGROUND

Immunoglobin G4 (IgG4)-related hypophysitis (IgG4-RH) is a rare form of IgG4-related disease (IgG4-RD), which often manifests as a single organ disease and is easily misdiagnosed as a pituitary tumor clinically and by imaging. There are few reports of imaging findings of IgG4-RH. Therefore, we describe a case of IgG4-RH, which mimicked a pituitary macroadenoma, that was detected by computed tomography (CT) and magnetic resonance imaging (MRI), and review the previous literature in order to further the understanding of IgG4-RH.

CASE SUMMARY

A 47-year-old man presented with a history of blurred vision for more than 2 mo, without other symptoms. A preoperative unenhanced CT scan revealed a slightly hyperdense mass in the sellar region measuring 2.5 cm × 2.3 cm × 1.8 cm, with a CT value of 45 HU. T1-weighted imaging (T1WI) and T2-weighted imaging showed iso-hypointensity, and gadolinium contrast-enhanced T1WI showed obvious homogeneous enhancement. The MRI revealed involvement of the pituitary gland and stalk. Preoperative laboratory tests revealed abnormal pituitary hormone levels, including an increased prolactin level, and decreased levels of insulin-like growth factor, dehydroepiandrosterone, and testosterone. The lesion was surgically resected. Postoperative histopathological examination of a tissue sample and an elevated serum IgG4 level confirmed the diagnosis of IgG4-RH. The patient was treated with cortisone acetate postoperatively and made a good recovery without developing any neurological deficit.

CONCLUSION

An elevated serum IgG4 concentration is the main clue for diagnosis of IgG4-RD. Imaging combined with laboratory testing is useful for preoperative diagnosis of IgG4-RH.

IgG4-related disease associated with the primary manifestation of recurrent cerebral venous thrombosis: A rare case report

Nervous system involvement in IgG4-related systemic disease (IgG4-RD) is rarely reported and manifests as hypertrophic pachymeningitis and hypophysitis. In this report, a 33-year-old woman with neurological manifestations was diagnosed with IgG4-RD by biopsy. The patient showed improvement in symptoms after treatment.

[A case of IgG4-related disease exclusively affecting pia matter and cerebral parenchyma]

A 61-year-old man presented with slowly progressive cognitive decline. Brain MRI revealed left frontal lobe lesions with gadolinium enhancement along pia mater. Brain biopsy was performed and histopathological findings was compatible with the diagnosis of IgG4-related disease (IgG4-RD). Serum IgG4 level was within a normal range, and no other systemic organs were suggested to be involved by clinical symptoms or laboratory findings. Intravenous methylprednisolone therapy followed by oral prednisone induction markedly improved the cognitive functions and MRI findings detected at the initial diagnosis. Our case highlights the importance of including IgG4-RD as one of the differential diagnosis when encountering the patients suffering from isolated cranial lesions even in the absence of normal serum IgG4 level.

IgG4-related disease presenting with multiorgan involvement

Immunoglobulin G4-related disease (IgG4-RD) is a rare fibroinflammatory immune-mediated condition which can affect multiple organ systems and form mass-like lesions. Initial presentation can mimic other diseases such as pancreatic malignancy when there is pancreatic involvement or tuberculosis (TB) when there are pulmonary lesions or hypertrophic pachymeningitis (HP). Here, we report a novel case of IgG4-RD presenting as bilateral subdural haematomas with additional findings. Our patient is a male who presented with headaches and blurred vision. Physical examination showed disconjugate gaze with a fixed pupil. Trauma survey radiologic imaging revealed a pancreatic mass concerning for malignancy. Subsequent workup found hypophysitis with optic chiasm compression and hypopituitarism, mediastinal lymphadenopathy and HP. Laboratory values showed an elevated serum IgG4 level and latent TB. Our case adds to the existing IgG4-RD literature by highlighting a unique presentation. It is important to maintain it on the differential diagnosis especially in multisystemic presentations with competing diagnoses.

Immunoglobulin G4-related disease presenting as an intracranial mass extended from the infratemporal fossa

Background

Neurological manifestations in immunoglobulin G4-related diseases (IgG4-RD) are rare and documented in <2% of cases. It commonly involves pachymeninges forming hypertrophic pachymeningitis and rarely forms tumor-like masses.

Case Description

We present our experience with a biopsy-proven case of IgG4-RD presenting with an intracranial extradural tumor-like mass infiltrating the temporal lobe. The patient was treated with high doses of corticosteroids followed by slow tapering. The neurological manifestations gradually improved and resolved after 2 months with a cerebral MRI showing a significant reduction in the tumoral size.

Conclusion

When it comes to intracranial mass, IgG4-RD neuropathy is one of the rarest differential diagnoses for the central nervous system tumors. Early recognition of IgG4-RD and appropriate establishment of its long-term treatment may avoid unnecessary investigations and morbidity.

It's Not All in Your Head: Thoracic Manifestations of Neurologic Diseases and Disorders

Myriad conditions may affect both the neurologic system and the thorax, while other diseases primarily affecting the thorax may manifest with neurologic abnormalities. Correlation of signs, symptoms, and imaging findings in the neurological system with those in the thorax can help diagnose certain conditions and/or guide further diagnostic work-up and treatment. We will review and illustrate the imaging appearance of several systemic/neurological diseases with thoracic manifestations as well as discuss conditions in the thorax that can lead to neurologic symptoms.

The great imposter: A case report of IgG4-RD hypertrophic pachymeningitis with skull lytic lesion and pulmonary nodules

Immunoglobulin G4-related disease (Ig4RD) is an inflammatory condition with unique clinical, serological, and pathological features. In this study, we report a challenging diagnostic clinical case of Ig4RD diagnosed based on histopathology. This unique imitating nature reinforces that it is crucial to consider the diagnosis of IgG4-RD in those presenting with pachymeningitis.

IgG4-Related Chronic Sinonasal Pseudotumor with Refractory Nasal Bleeding: A Case Report

Immunoglobulin G4-related disease (IgG4-RD) is a systemic fibro-inflammatory and idiopathic autoimmune disorder. IgG4-RD can be characterized by the presence of pseudotumors. Inflammatory pseudotumors may involve any part of a human organ. There are few reports of sinus lesions in IgG4-RD. An 82-year-old man has a history of chronic sinusitis for the last several years and no remarkable family history. Two years before disease presentation, the patient experienced intermittent nasal bleeding, stuffy nose, dizziness, and fatigue. Blood test revealed positive (160X) antinuclear antibody with a mixed speckled and nucleolar pattern, IgG level of 1370 mg/dL, and IgG4 level of 99.7 mg/dL. Computed tomography (CT) of the sinus revealed several calcifications in the sphenoid sinus. Surgical findings revealed tumor-like materials. Pathological examination of the soft tissues revealed acute and chronic granulomatous inflammation. Immunohistochemical analysis demonstrated high levels of positive-affinity markers of IgG, IgG4, and CD138 and a IgG4/IgG ratio > 40%. IgG4-RD with pseudotumor was diagnosed. The initial treatment was intravenous methylprednisolone 120 mg daily for three days and oral prednisolone 10 mg twice a day and azathioprine 50 mg daily. The efficacy of the treatment was insufficient, and nasal bleeding did not decrease. Subsequently administered intravenous rituximab 1000 mg monthly for 2 months. Following this treatment, nasal bleeding stopped. CT revealed reduction in nasal mucosal swelling compared with that in a previous scan. This report highlights that in cases with an inflammatory mass mimicking malignancy, IgG4RD should always be considered, and rituximab treatment is recommended upon failure of steroid and azathioprine therapy.

IgG4-Related Disease Presenting as Hypertrophic Pachymeningitis

IgG4-related disease (IgG4-RD) is a multi-organ, immune-mediated inflammatory condition of unknown etiology characterized by infiltration of tissues by IgG4 producing plasma cells. IgG4-related disease (IgG4-RD) can ideally affect any organs, but the involvement of the central nervous system (CNS) is a rare entity. We present a case of a 67-year-old male who presented with diplopia with imaging showing hypertrophic pachymeningitis (HPM) and was diagnosed with IgG4-RD of the CNS based on histopathology report.

IgG4-related hypertrophic pachymeningitis with tumor-like intracranial and intracerebral lesions

OBJECTIVE

IgG4-related hypertrophic pachymeningitis is a rare fibroinflammatory disorder that may cause localized or diffused thickening of the dura mater. Misinterpretations of the clinical and imaging findings are common. Clinical manifestations depend on the location of the inflammatory lesion and on compression of neural structures leading to functional deficits. A dural biopsy is commonly needed for a definitive diagnosis. Immunomodulatory therapy is considered the therapy of choice.

METHODS

Four patients with IgG4-related hypertrophic pachymeningitis were identified over a 5-year period. Patient-related characteristics including age, preoperative workup, signs and symptoms of patients, and diagnostic procedures were evaluated. Furthermore, the surgical treatment and 5-year follow-up outcomes were analyzed.

RESULTS

There were two adults and two adolescents (mean age 32 years; range 15 to 67 years). Two patients were male, and two were female. No history of disease was known in any of the patients. Clinical symptoms were epilepsy (n = 2), ataxia and nausea (n = 1), and facial nerve palsy (n = 1). MR imaging studies showed contrast enhancing lesions in the temporal region in two patients, and in the cerebellar region in the other two patients. Subtotal resection was performed in two instances and a biopsy via a suboccipital retrosigmoid approach was obtained in the other two patients. Histochemical and immunohistochemical investigations revealed an IgG 4 disease in all of these patients. Immunomodulatorry therapy led to clinical stability during follow-up of 5 years in all four cases.

CONCLUSION

The diagnosis of IgG4-related hypertrophic pachymeningitis is challenging, but is of great relevance as treatment differs significantly from other forms of pachymeningitis and a specific therapeutic approach may avoid long-term neurological complications. Our series contributes to a better clinical characterization of this rare disease.

Immunoglobulin G4-related disease of the cavernous sinus with orbit invasion - A case report

Background

Immunoglobulin G4-related disease (IgG4-RD) is a rare systemic disease of unknown etiology. It is characterized by tissue infiltration caused by IgG4 plasma cells and sclerosing inflammation of various body organs. At present, there are very few reported cases of IgG4-RD invasion of cavernous sinus and the orbit.

Case Description

A 56-year-old female with a history of rheumatoid arthritis was presented with a gradual onset of right oculomotor, abducens, and trigeminal nerve deficits. Four weeks after the onset of symptoms, the patient developed gradual visual deficit. Following this, a trial of steroids was administered to the patient. However, the treatment did not work as expected and patient's condition worsened. She progressed on to suffer complete visual loss in the right eye. Extensive work-up conducted on her turned out to be nondiagnostic. After this, the patient was referred to us for our evaluation. Neuroimaging revealed a right-sided cavernous sinus and orbital apex lesion. Given the lack of diagnosis and response to steroid treatment, we recommended surgical intervention and performed a modified pterional and pretemporal approach with extradural anterior clinoidectomy and transcavernous approach. We performed a lesion biopsy and cavernous sinus decompression, which helped in the partial recovery of visual function. The pathology report was consistent with IgG4-RD.

Conclusion

IgG4-RD is a rare disease that occurs even less in combination with cavernous sinus and orbit invasion. The rarity of the disease and the diverse presentation of symptoms have sometimes caused delayed diagnosis and intervention. Patients who failed to respond to conservative management and patients in the fibrotic stage of the disease without other organ involvement may benefit from surgical intervention if amenable. Early suspicion, diagnosis, and intervention can facilitate better prognosis.

IgG4-related pachymeningitis masquerading as foramen magnum meningioma: illustrative case

BACKGROUND

Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated inflammatory condition with potential multiorgan involvement. Common manifestations include autoimmune pancreatitis and retroperitoneal fibrosis. Pathological analysis reveals lymphoplasmacytic infiltrate rich in IgG4-positive cells and characteristic storiform fibrosis. Early treatment with glucocorticoids may prevent progression to poorly responsive fibrotic disease.

OBSERVATIONS

A 63-year-old female patient presented with reports of left-sided headaches, nausea, and photophobia in addition to recently diagnosed chronic rhinosinusitis (CRS). Neurological examination revealed dysarthria secondary to left hypoglossal nerve palsy. Computed tomography (CT) revealed a contrast-enhancing extraaxial mass at the left craniocervical junction, CRS with secondary hyperostotic reaction, and multiple hypodense lesions involving the occipital bone. Magnetic resonance imaging revealed a dural-based lesion involving the foramen magnum and invading the left hypoglossal canal. The patient underwent a far-lateral craniotomy. Histopathological analysis revealed severe lymphoplasmacytic inflammation, storiform fibrosis and rich plasma-cell population positive for IgG4. Serum IgG4 was markedly elevated. Total-body CT showed no systemic involvement. The patient was diagnosed with IgG4-RD and was prescribed prednisone, with normalization of her IgG4 levels after 1 month.

LESSONS

IgG4-RD may mimic a variety of diseases, including skull-base meningiomas and CRS. Accurate diagnosis and expedited administration of steroids may prevent unnecessary interventions and progression to treatment-resistant fibrosis.

Intracranial Tumors Associated With IgG4-Related Disease

IgG4-related disease (IgG4-RD) is an immune-mediated inflammatory condition which is characterized by dense lymphoplasmacytic infiltrations with a predominance of IgG4 plasma cells in the affected tissue. Although pachymeninx and pituitary gland are the most common sites where IgG4-RD infiltrates, the associations with IgG4-RD and a true intracranial tumor have not been yet reported in literature. Herein, we report two cases with intracranial tumors associated with IgG4-RD; a 36-year-old male patient with a huge meningioma and another 54-year old woman with a pituitary macroadenoma. Pathological examination revealed their tumors were substantially infiltrated by IgG4 plasma cells indicating its possible relation with IgG4-RD.

Nerve biopsy: Current indications and decision tools

After initial investigation of patients presenting with symptoms suggestive of neuropathy, a clinical decision is made for a minority of patients to undergo further assessment with nerve biopsy. Many nerve biopsies do not demonstrate a definitive pathological diagnosis and there is considerable cost and morbidity associated with the procedure. This highlights the need for appropriate selection of patients, nerves and neuropathology techniques. Additionally, concomitant muscle and skin biopsies may improve the diagnostic yield in some cases. Several advances have been made in diagnostics in recent years, particularly in genomics. The indications for nerve biopsy have consequently changed over time. This review explores the current indications for nerve biopsies and some of the issues surrounding its use. Also included are comments on alternative diagnostic modalities that may help to supplant or reduce the use of nerve biopsy as a diagnostic test. These primarily include extraneural biopsy and neuroimaging techniques such as magnetic resonance neurography and nerve ultrasound. Finally, we propose an algorithm to assist in deciding when to perform nerve biopsies.

Intrathecal activation of CD8+ memory T cells in IgG4-related disease of the brain parenchyma

IgG4-related disease (IgG4-RD) is a fibroinflammatory disorder signified by aberrant infiltration of IgG4-restricted plasma cells into a variety of organs. Clinical presentation is heterogeneous, and pathophysiological mechanisms of IgG4-RD remain elusive. There are very few cases of IgG4-RD with isolated central nervous system manifestation. By leveraging single-cell sequencing of the cerebrospinal fluid (CSF) of a patient with an inflammatory intracranial pseudotumor, we provide novel insights into the immunopathophysiology of IgG4-RD. Our data illustrate an IgG4-RD-associated polyclonal T-cell response in the CSF and an oligoclonal T-cell response in the parenchymal lesions, the latter being the result of a multifaceted cell-cell interaction between immune cell subsets and pathogenic B cells. We demonstrate that CD8⁺ T effector memory cells might drive and sustain autoimmunity via macrophage migration inhibitory factor (MIF)-CD74 signaling to immature B cells and CC-chemokine ligand 5 (CCL5)-mediated recruitment of cytotoxic CD4⁺ T cells. These findings highlight the central role of T cells in sustaining IgG4-RD and open novel avenues for targeted therapies.

A Tale of Two Organ Systems: Imaging review of diseases affecting the thoracic and neurological systems. Part 1

In an era of rapidly expanding knowledge and sub-specialization, it is becoming increasingly common to focus on one organ system. However, the human body is intimately linked, and disease processes affecting one region of the body not uncommonly affect the other organ systems as well. Understanding diseases from a macroscopic perspective, rather than a narrow vantage point, enables efficient and accurate diagnosis. This tenet holds true for diseases affecting both the thoracic and neurological systems; in isolation, the radiologic appearance of disease in one organ system may be nonspecific, but viewing the pathophysiologic process in both organ systems may markedly narrow the differential considerations, and potentially lead to a definitive diagnosis. In this article, we discuss a variety of disease entities known to affect both the thoracic and neurological systems, either manifesting simultaneously or at different periods of time. Some of these conditions may show neither thoracic nor neurological manifestations. These diseases have been systematically classified into infectious, immune-mediated / inflammatory, vascular, syndromic / hereditary and neoplastic disorders. The underlying pathophysiological mechanisms linking both regions and radiologic appearances in both organ systems are discussed. When appropriate, brief clinical and diagnostic information is provided. Ultimately, accurate diagnosis will lead to expedited triage and prompt institution of potentially life-saving treatment for these groups of complex disorders.

A Unique Case of Encephalopathy with an Elevated IgG-4 and Extremely High Interleukin-6 Level and Delayed Myelodysplastic Syndrome

We herein report a 75-year-old man who developed disturbed consciousness with polynuclear cell dominant pleocytosis and low glucose and extremely high interleukin (IL)-6 levels in his cerebrospinal fluid. The biopsy specimen from his right supraclavicular lymph node showed the infiltration of inflammatory cells positive for IgG, IgG4 and IL-6. Prednisolone and azathioprine administered under suspicion of IgG4-related disease (IgG4-RD) or multicentric Castleman's disease (MCD) successfully remitted the symptoms. However, he developed myelodysplastic syndrome (MDS) and died 18 months later. The extremely high IL-6 may have been related to the rare neurological manifestations and development of MDS in the present case.

The First Case of Eosinophilic Granulomatosis with Polyangiitis Simultaneously Demonstrating Various Clinical Manifestations with Retroperitoneal Fibrosis and Membranous Nephropathy

The first case of eosinophilic granulomatosis with polyangiitis (EGPA) simultaneously demonstrating various clinical manifestations, including retroperitoneal fibrosis (RPF) causing hydronephrosis and membranous nephropathy (MN) leading to nephrotic syndrome, is presented. There have been no previous case reports demonstrating the simultaneous onset of these three disease categories with significant complex pathologies. This case was successfully managed by providing adequate combination therapies according to each disease category, leading to complete remission (CR) of all three diseases. In conclusion, we believe this case is extremely rare and clinically suggestive, and that these findings can be applied to a future phenotype-tailored treatment strategy for EGPA.

Immunoglobulin G4-related Disease Accompanied by Peripheral Neuropathy: A Report of Two Cases

Due to its rarity and the limited literature, the clinicopathological characteristics of peripheral nerve involvement in immunoglobulin G4 (IgG4)-related disease are unknown. We present two cases of IgG4-related disease, accompanied by peripheral neuropathy, presenting as unilateral ptosis (case 1) and sclerosing cholangitis (case 2), respectively. In both cases, sural nerve biopsy indicated vasculitis as the underlying pathophysiology; the peripheral neuropathy was refractory to corticosteroid therapy. In contrast to the previously proposed pathomechanism of IgG4-related neuropathy (direct lymphoplasmacytic infiltration), the pathological findings in our cases suggest that vasculitis occurs secondary to systemic autoimmune conditions.

18F-FDG PET/CT Manifestations of IgG4-related Disease

Immunoglobulin G4-related disease (IgG4-RD) was not recognised as a systemic condition until 2003, when extra pancreatic manifestations were identified in patients with autoimmune pancreatitis. Since then, IgG4-RD has been described to involve virtually every organ system. It is highly responsive to immunosuppressants but can have detrimental effects if left untreated. Early recognition of the disease is, therefore, critical. The diagnosis of IgG4-RD is frequently challenging owing to its non-specific clinical manifestations, indolent nature and broad differential diagnoses. Although histopathological examination remains the cornerstone of diagnosis, imaging plays an important role in establishing extent of disease and identifying areas suitable for biopsy. ¹⁸F-Fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) has been demonstrated to be useful in assessing organ involvement, guiding biopsy and monitoring disease response. The ¹⁸F-FDG PET/CT scan is highly sensitive and able to evaluate multiorgan involvement in a single examination, a key advantage over conventional imaging modalities. A potential pitfall is its low specificity. As such, detailed knowledge of the imaging findings in IgG4-related disease is required to avoid misdiagnosis. This pictorial review aims to depict the diverse spectrum of imaging findings of IgG4-RD and the key imaging features to distinguish it from other important differential diagnoses.

Successful treatment of IgG4-related hypertrophic pachymeningitis with induction rituximab and dexamethasone followed by maintenance rituximab

IgG4-related disease (IgG4RD) with intracranial involvement is rare. We report a 56-year-old male who had an excellent response to rituximab and dexamethasone after going undiagnosed for 5 years. After 3 years of rituximab maintenance, he has no evidence of disease on brain MRI.

The protean manifestations of central nervous system IgG4-related hypertrophic pachymeningitis: a report of two cases

Background

IgG4-related hypertrophic pachymeningitis is a relative newly recognized and rare manifestation of IgG4-related disease, an immune-mediated fibroinflammatory tumefactive disorder. Fewer than 80 patients have been reported in the literature, and it can mimic common neurosurgical conditions. We describe the clinical presentation of two patients that were initially considered to have a subdural collection, tuberculous meningitis, and a cervical spinal meningioma, but were eventually diagnosed with this disease.

Case presentation

Two ethnic Chinese men, 86 and 62 years old, experienced a 4-week history of headache. Both patients had a history of autoimmune disease, namely glomerulonephritis and Grave’s disease, respectively. Magnetic resonance brain imaging revealed diffuse dural thickening with the latter patient exhibiting homogeneous and intense gadolinium-contrast enhancement. Since the 86-year-old patient also had progressive bilateral visual loss, giant cell arteritis was suspected and a 2-week course of glucocorticoid therapy was prescribed, but his symptoms failed to improve. The 62-year-old patient also had accompanying low-grade fever and was treated empirically as having tuberculous meningitis although there were no confirmatory microbiological findings. This patient further developed right hemiparesis, and additional imaging revealed a C4/5 intradural-extramedullary contrast-enhancing lesion resembling a meningioma causing cord compression. Both patients underwent neurosurgical intervention with the former undergoing a dural biopsy and the latter having the cervical lesion resected. The final diagnosis was IgG4-related hypertrophic pachymeningitis with the hallmark histological features of lymphoplasmacytic infiltration of IgG4+ plasma cells, storiform fibrosis, and obliterative phlebitis. In addition, their serum IgG4 levels were elevated (i.e., > 135 mg/dL). Both patients received at least 6 months of glucocorticoid therapy while the latter also had azathioprine. Their symptoms improved significantly and recurrent lesions were not detected on follow-up imaging.

Conclusions

A high index of suspicion for this condition is suggested when a male patient with a history of autoimmune disease and compatible radiological findings, experiences subacute headache that is disproportionate to the degree of dural involvement. Neurosurgeons should consider early meningeal biopsy to establish a definitive histological diagnosis in order for early effective immunosuppressive treatment to be initiated and to avoid unnecessary morbidity.

Immune-Mediated Disorders Affecting the Spinal Cord and the Spine

PURPOSE OF REVIEW

To review the most recent advances and provide a description of the most common autoimmune diseases causing myelitis and selective spine disorders. The ultimate goal of this article is to facilitate the prompt recognition of these diseases.

RECENT FINDINGS

The recent discovery of biomarkers such as aquaporin 4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibodies has changed our understanding of autoimmune diseases affecting the spinal cord as well as their treatment and outcomes. Autoimmune neurology is an increasingly evolving field that encompasses a broad spectrum of autoimmune-inflammatory diseases of the central nervous system (CNS) and peripheral nervous system (PNS). Autoimmune disorders of the spinal cord are a heterogeneous group of myelopathies with a broad differential diagnosis and many of them have been recently identified. Prompt recognition of these myelopathies is important as some of them are treatable, which could improve patient outcomes and prevent disability.

Neurosurgical and neuro-immunological management of IgG4-related hypertrophic sclerosing pachymeningitis. A literature survey and discussion of a unique index case

BACKGROUND

Dural thickening is observed in lymphoma, dural carcinomatosis, meningioma, tuberculosis, and autoimmune diseases. We encountered a patient with dural thickening and complaints of neck and back pain, numbness and loss of strength in the hands. The patient also suffered from polychondritis and had previously received steroid and methotrexate treatment for this indication. The patients' serum was also positive for ANA, yet she did not have any other findings suggesting lupus. Our radiological and pathological analysis revealed IHSP (IgG4-related hypertrophic sclerosing pachymeningitis). In this review study, we provided a detailed literature survey to increase the awareness about IHSP in the neurosurgical community.

METHODS

MRI (magnetic resonance imaging)-based radiological analyses revealed a posterior extramedullary spinal mass extending from C2 to T2-T3 level. The dural mass was surgically excised and a broad panel of immunohistochemical markers including S100, EMA, CD246/ALK-1, CD45, CD20, CD79a, CD138, CD68, CD1a and CD34 was studied. Immunoglobulin heavy chain/kappa chain gene rearrangement analysis was performed which ruled out a lymphoproliferative disorder.

RESULTS

MRI and pathological findings suggested IHSP. As the disease relapsed with a new anterior extramedullary multilobulated lesion extending from C5 to T1 level, the patient is now closely monitored for further medical and surgical treatment.

CONCLUSIONS

IHSP is a relatively novel entity of hypertrophic pachymeningitis and should be included in the differential diagnosis of dural thickening. The fibrosis accompanying IHSP may not respond to medical treatment, which includes steroids and immunosuppressive agents. Additionally, neurological deficits, seizures, spinal decompression, hydrocephalus, or brainstem compression necessitate early surgical intervention. A continued vigilance is also necessary as the disease may relapse long-term following surgical treatment.

An Update on Idiopathic Hypertrophic Cranial Pachymeningitis for the Headache Practitioner

PURPOSE OF REVIEW

We aim to review idiopathic hypertrophic cranial pachymeninigitis (IHCP), describe common head pain patterns and features associated with the disorder, suggest potential classification of head pain syndromes based on the recently published International Classification of Headache Disorders-3, explore pathophysiology found to be associated with cases of IHCP, and indicate common treatment for the disorder.

RECENT FINDINGS

It is suggested that a subset of IHCP is an IgG4-related autoimmune disorder. Patients with IHCP were found to have elevated cerebrospinal fluid (CSF) protein and lymphocytic pleocytosis. Corticosteroids are a mainstay of treatment. Other immunosuppressive agents and steroid sparing agents as add-on therapy may have utility in the treatment of cases refractory to corticosteroids alone. Clinical manifestations of IHCP depend upon the location of the inflammatory lesions and compression of the adjacent nervous system structures. Headache and loss of cranial nerve function were the most common presenting features of hypertrophic cranial pachymeninigitis. Several headache diagnoses may result from IHCP. Gadolinium-enhanced MRI is the standard imaging modality for diagnosing. Although the pathophysiology is poorly understood, many cases of hypertrophic pachymeninigitis (HP) are thought to be closely related to inflammatory disorders. Cases of HP previously thought to be idiopathic may have IgG4 pathophysiology. CSF and serological studies are helpful. Treatment involves immunosuppressive agents. Advancement in neuroimaging, assays, tests, and further delineation of inflammatory disorders affecting the nervous system may provide further insight to the etiology of cases of HP previously considered and diagnosed as idiopathic.

Cavernous sinus lesions

The cavernous sinus is a complex structure susceptible to a wide variety of vascular, neoplastic and inflammatory pathologies. Vascular pathologies include ICA aneurysms, carotid-cavernous fistulas, cavernous sinus thrombosis, and cavernous hemangioma. Neoplasms that involve the cavernous sinus include pituitary adenoma, meningioma, schwannoma, lymphoma, perineural tumor spread, metastases, and direct tumor invasion. Infectious and inflammatory diseases include Tolosa-Hunt syndrome, sarcoidosis, granulomatosis with polyangiitis, IgG-4 related disease and invasive fungal infections. In this article, we review the clinical and imaging findings of a number of pathologies involving the cavernous sinus, focusing on key features that can narrow the differential diagnosis and, in some cases, support a particular diagnosis.

Recurrent myelitis and asymptomatic hypophysitis in IgG4-related disease: case-based review

IgG4-related disease (IgG4-RD) is a disorder with various clinical manifestations. Central nervous system (CNS) involvement is well recognized, with hypertrophic pachymeningitis and hypophysitis being the most common manifestations. Spinal cord involvement is an extremely rare manifestation. We present the first case of an IgG4-RD patient with spinal cord parenchymal disease and concurrent hypophysitis. We review also the current literature about CNS parenchymal involvement in the context of IgG4-RD. A young female presented with clinical symptoms of myelitis. Cervical spinal cord magnetic resonance imaging (MRI) displayed features of longitudinally extensive transverse myelitis (LETM). Brain MRI showed a small number of high-intensity lesions in the deep white matter and enlargement of hypophysis with homogeneous gadolinium enhancement (asymptomatic hypophysitis). Diagnostic workup revealed elevated IgG4 serum levels (146 mg/dL). Our patient fulfilled the organ-specific diagnostic criteria of IgG4-hypophysitis. Treatment with intravenous glucocorticoids led to rapid clinical response, and to the substantial resolution of imaging findings. Azathioprine was used as a maintenance treatment. One relapse occurred 2 years after the initial diagnosis and patient was re-treated with glucocorticoids. Three years after relapse, patient is in remission with azathioprine. We present the first case of myelitis with radiological features of LETM associated with increased IgG4 serum levels and the simultaneous presence of asymptomatic IgG4-related hypophysitis.