Neurosarcoidosis: a clinical dilemma

[A case of neurosarcoidosis initially diagnosed as cervical spondylotic myelopathy, leading to diagnosis by gadolinium contrast-enhanced MRI]

A 70-year-old female presented with bilateral numbness in her upper limbs. She was diagnosed with cervical spondylotic myelopathy and underwent cervical laminoplasty. However, there was no significant improvement in sensory disturbance, and at 6 months after surgery, she developed subacute motor and gait disturbance in four extremities. Spinal MRI revealed a long lesion of the spinal cord with edema, and a part of the lesion showed gadolinium contrast enhancement. Bronchoscopy revealed an elevated CD4/8 ratio, and gallium scintigraphy demonstrated an accumulation in the hilar lymph nodes, leading to a diagnosis of neurosarcoidosis. In case of rapid deterioration during the course of cervical spondylotic myelopathy, neurosarcoidosis should be considered as a differential diagnosis, which can be assessed by contrast-enhanced MRI.

Uncommon and Miscellaneous Inflammatory Disorders of the Brain and Spine

Inflammatory disorders of the brain and spine have a highly variable MRI appearance, often demonstrating significant overlap in imaging features. The resulting diagnostic dilemma is particularly challenging when considering the more uncommon neuroinflammatory entities. Diligent examination of the salient clinical presentation and signal alteration on imaging examination is necessary when considering neuroinflammation as a diagnostic possibility and may aid in raising suspicion for a particular neuroinflammatory entity. This article reviews a selection of uncommon and miscellaneous inflammatory disorders of the brain and spine to raise awareness of the clinical and imaging features that may assist in this challenging diagnostic task.

Neurosarcoidosis and Transverse Myelitis: Life-Threatening Manifestations of Sarcoidosis

Sarcoidosis, a systemic granulomatous disorder, typically involves the lungs, skin, and lymph nodes. Neurological manifestations are diverse and may include longitudinally extensive transverse myelitis (LETM), an uncommon inflammatory disorder of the spinal cord. We present a case of a 62-year-old female with LETM as the initial manifestation of sarcoidosis. The patient exhibited progressive bilateral lower extremity weakness, urinary retention, and sensory disturbances. Diagnostic workup revealed characteristic findings on spinal magnetic resonance imaging (MRI), cerebrospinal fluid analysis, and thoracic biopsy. Treatment with high-dose corticosteroids and subsequent immunomodulatory therapy resulted in significant improvement. Our case highlights the importance of including sarcoidosis in the differentials of LETM, particularly in patients with no respiratory manifestations.

Neurosarcoidosis, Coccidioidomycosis, or Both!

Purpose

To report a case of neurosarcoidosis (NS) who was initially diagnosed as Coccidioidomycosis immitis (CI) infection.

Observations

A 57-year-old diabetic man presented with sudden painless diminution of vision, metamorphopsia, and color vision deficits in the left eye (OS) for one month. His vision was 20/20 in the right eye (OD) and 20/40 OS. Ophthalmic examination revealed left relative afferent pupillary defect, blurred optic nerve margin, creamy chorioretinal infiltration around the optic disc, and mild macular edema. OD examination was non-revealing. Chest CT scan with contrast showed calcified mediastinal lymph nodes, but biopsy of the lymph nodes was normal. Brain and orbit MRI demonstrated soft tissue abnormality with enhancement in left orbital apex with involvement of the extraocular muscles. CSF culture was negative, but complement fixation had positive titer of 1:2 for CI. The patient was diagnosed with CI meningitis, and antifungal therapy was initiated. Slight visual and symptomatic improvement was observed, which was not completely satisfactory. Biopsy of extraocular orbital muscle five months later revealed non-caseating granulomatous inflammation, leading to initiation of prednisone trial therapy. Nine months later, the patient was referred to a tertiary center owing to persistence of optic disc edema OS. PET CT was consistent with a diagnosis of sarcoidosis. Antifungal treatment was discontinued, and oral prednisone with methotrexate was initiated. Subsequently, methotrexate was replaced by infliximab to further manage ocular inflammation and neurologic symptoms which was effective. Vision was 20/20 OD and 20/30 OS at the most recent visit.

Conclusion and Importance

Signs and symptoms of neurosarcoidosis and coccidioidomycosis can be similar and deceiving. The index case underscores importance of considering appropriate differential diagnoses in patients with similar symptoms and signs who may respond to preliminary designated treatment but not to the optimal extent. Considering such possibility could assist clinicians in managing the patients timely and efficiently.

A Unique Case of Sarcoid-associated Myelopathy Accompanied by Lung Cancer

The differential diagnosis of myelopathy in patients with malignancies may be challenging, as a spinal biopsy is not always applicable. A 66-year-old woman who had shown transient double vision and nausea developed spasticity and impaired deep sensation in both feet. Magnetic resonance imaging showed abnormal gadolinium enhancement of the brainstem, spinal meninges, and nerve root. Cerebrospinal fluid (CSF) revealed mild pleocytosis and elevated protein and decreased glucose levels, although CSF cytology was normal. Lung carcinoma was simultaneously detected, and noncaseating granuloma was detected from the hilar and axillary lymph nodes, so she was diagnosed with sarcoid-associated myelopathy. Her symptoms were kept stable by intravenous methylprednisolone, oral prednisolone, and methotrexate. This is the first case of sarcoid-associated myelopathy accompanied by lung cancer, suggesting the importance of clinical course, repetitive CSF cytology, and a biopsy of the lymph nodes to distinguish sarcoid-associated myelopathy from meningeal metastasis in patients with malignancies.

Cerebral lesions sites in neurosarcoidosis: a lesion mapping study

BACKGROUND AND PURPOSE

Sarcoidosis is a granulomatous disease of unknown etiology affecting the central nervous system in up to 15% of the patients. Diagnosis of neurosarcoidosis is very challenging due to the heterogeneity of its clinical manifestation. This study intended to evaluate the distribution of cerebral lesion sites and the potential presence of specific lesion clusters in neurosarcoidosis patients using voxel-based lesion symptom mapping (VLSM).

METHODS

Patients with neurosarcoidosis were retrospectively identified and included between 2011 and 2022. Cerebral lesion sites were correlated voxel-wise with presence and absence of neurosarcoidosis using non-parametric permutation test. Multiple sclerosis patients served as controls for the VLSM-analysis.

RESULTS

Thirty-four patients (mean age 52 ± 15 years) of whom 13 were diagnosed with possible, 19 with probable and 2 with confirmed neurosarcoidosis were identified. Lesion overlap of neurosarcoidosis patients demonstrated a distribution of white matter lesions in all brain areas, with a periventricular predilection similar to multiple sclerosis. In contrast to multiple sclerosis controls, no propensity for lesions in proximity of the corpus callosum was observed. Neurosarcoidosis lesions appeared smaller and lesion volume was lower in the neurosarcoidosis cohort. The VLSM analysis showed minor associations between neurosarcoidosis and damaged voxels in the bilateral frontobasal cortex.

CONCLUSIONS

The VLSM analysis yielded significant associations in the bilateral frontal cortex, suggesting that leptomeningeal inflammatory disease with following cortical involvement is a quite specific feature in neurosarcoidosis. Lesion load was lower in neurosarcoidosis than in multiple sclerosis. However, no specific pattern of subcortical white matter lesions in neurosarcoidosis was revealed.

A Perplexing Case of Bladder Mass Biopsy-Proven Neurosarcoidosis

Sarcoidosis is a multi-organ systemic disease that presents with several clinical manifestations, and patients can develop neurologic complications. Neurosarcoidosis may be life-threatening; therefore, early recognition and treatment are key. Here, we present a case of a 55-year-old African American male who presented with a complaint of dizziness and left-sided weakness; he ultimately received a diagnosis of neurosarcoidosis after elaborate radiographic investigations and bladder mass biopsy. Neurosarcoidosis remains a diagnostic dilemma as it can clinically and radiographically mimic multiple conditions including multiple sclerosis, central nervous system lymphoma, multiple myeloma, and progressive multifocal leukoencephalopathy.

Cerebrospinal fluid B-cell activating factor levels as a novel biomarker in patients with neurosarcoidosis

OBJECTIVES

Neurosarcoidosis (NS) is a severe complication of sarcoidosis. Patients with NS often have poor outcomes. To improve both the quality of life and prognosis in patients with NS, accurate and reliable methods for early diagnosis and determining the efficacy of treatment are needed. This study aims to investigate B-cell-activating factor of the tumor necrosis factor family (BAFF) in cerebrospinal fluid (CSF) and elucidate the relationship between CSF BAFF levels and various parameters of NS.

METHODS

We studied 20 patients with NS and 14 control subjects. We measured CSF BAFF levels in all subjects and investigated the relationship with clinical findings, serum and CSF measures, and magnetic resonance imaging (MRI) findings.

RESULTS

CSF BAFF levels were significantly increased in patients with NS compared with controls (median 0.089 vs 0.04 ng/mL, p = 0.0005). CSF BAFF values were correlated with CSF findings-cell count, protein, angiotensin-converting enzyme, lysozyme, soluble interleukin-2 receptor, and immunoglobulin G-but not with serum parameters. CSF BAFF levels were especially higher in patients with abnormal intraparenchymal lesions of the brain and abnormal spinal MRI findings. CSF BAFF levels decreased significantly after immunosuppressive therapy.

CONCLUSION

CSF BAFF may aid the quantitative evaluation of NS and may serve as a biomarker for this disease.

Rare Presentations of Sarcoidosis: A Case Series

Sarcoidosis is a systemic disease of unknown etiology with multi-system affection. It typically involves the skin, eyes, hilar lymph nodes, and pulmonary parenchyma. However, as any organ system could be involved, one has to be aware of its atypical manifestations. We present three uncommon manifestations of the disease. Our first case presented with fever, arthralgias, and right hilar lymphadenopathy with a history of tuberculosis in the past. He was treated for tuberculosis but had a relapse of symptoms three months after completion of treatment. The second patient presented with a headache for two months. On evaluation, cerebrospinal fluid examination showed evidence of aseptic meningitis, while an MRI of the brain demonstrated enhancement of the basal meninges. The third patient was admitted with a mass on the left side of the neck for one year. On evaluation, he was found to have left cervical lymphadenopathy, with its biopsy showing non-caseating epitheloid granuloma. Immunofluorescence did not show evidence of leukemia or lymphoma. All the patients had negative tuberculin skin tests and elevated serum angiotensin-converting enzyme levels supporting the diagnosis of sarcoidosis. They were treated with steroids with complete resolution of symptoms and no recurrence at follow-up. Sarcoidosis is an underdiagnosed entity in India. Thus, awareness of the atypical clinical features could lead to early recognition of the disease and its treatment.

Neurosarcoidosis Presenting as Longitudinally Extensive Transverse Myelitis and Orbital Mass: A Case Report

We describe a case of neurosarcoidosis in a 64-year-old female who presented with proptosis and orbital inflammation together with bilateral lower extremity neuropathy and longitudinally extensive transverse myelitis. These two entities are not commonly associated, and the etiology of the transverse myelitis was facilitated by an orbital biopsy. The transverse myelitis caused numbness in her lower extremities and tightness in her chest and abdomen, which progressed over weeks to difficulty walking and bilateral neuromuscular weakness. Magnetic resonance imaging (MRI) revealed longitudinally extensive transverse myelitis in the cervical and thoracic spine. Computed tomography (CT) imaging of the chest revealed right hilar and mediastinal lymphadenopathy and calcified subcarinal nodes. Positron emission tomography (PET) scan revealed hypermetabolism in the mediastinum and medial left orbit. Orbital biopsy revealed non-necrotizing granulomatous inflammation suggestive of sarcoidosis. The neurologic deficits and orbital inflammation responded well to intravenous corticosteroids. Neurosarcoidosis can present with unusual clinical manifestations, as evidenced by this patient.

Neurosarcoidosis in children: A systematic review and summary of cases, imaging and management

Neurosarcoidosis is a rare disorder in children. We identified 30 pediatric NS cases through a systematic review. Twenty-one (70%) had systemic sarcoidosis with 30% having primary neurosarcoidosis. Eyes (37%), lymph nodes (37%) and lungs (30%) were most commonly involved. Isolated neurosarcoidosis were more likely in children (30%) than in adults (6%, p = 0.0005). Seizures and optic neuritis were also more common in children than adults (33% vs 14%, p = 0.002; and 30% versus 6%, p = 0.008, respectively). Evaluation, imaging, laboratory findings, and treatments are discussed. Additional research, including multi-center studies, is needed.

Perspective of sarcoidosis in terms of rheumatology: a single-center rheumatology clinic experience

Sarcoidosis may present with many rheumatological symptoms as well as mimic and/or may occur concomitantly with many other rheumatic diseases. We examined the demographic, clinical and laboratory characteristics of patients diagnosed with sarcoidosis in the rheumatology department. This study planned as retrospective cross-sectional study. Medical records of patients who applied to our rheumatology outpatient clinic due to complain of musculoskeletal problems and then diagnosed sarcoidosis were retrospectively investigated. Joint findings, extrapulmonary involvements, and coexisting rheumatic disease were evaluated. Fifty-six patients (41.21 ± 7.83 years, 75% female) were included. The duration of the disease was 49.61 ± 29.11 months, and the follow-up period was 26.66 ± 13.26 months. All patients had pulmonary system involvement. Arthralgia was present in 91.10% of 56 patients and arthritis in 89.29% of patients. Examining the subtypes of the arthritis findings, mono-arthritis was found in 31/50 (62%) patients, oligo-arthritis in 15/50 (30%) patients, and polyarthritis in 4/50 (8%) patients. A total of 11 (19.60%) patients were diagnosed with uveitis. Excision of the mediastinal LAP was performed in a total of 37 patients (66.1%) and became the most commonly employed method. Considering the treatment distribution of the patients under followed-up, it is seen that non-steroidal anti-inflammatory treatments were used in 15 (26.8%) patients, corticosteroids in a total of 40 (71.4%) patients, methotrexate in a total of 15 patients (26.8%), azathioprine in six (10.7%) patients, hydroxychloroquine in 14 (25%) patients, and infliximab in one (1.8%) patient. As sarcoidosis is a mimicking disease, a good differential diagnosis should be made to avoid misdiagnosis and in order not to be late in diagnosis and treatment. Physicians, especially rheumatologists, should remember sarcoidosis more frequently as the disease may overlap with other rheumatological diseases and may occur with many rheumatological manifestations.

Adult-Onset Genetic Central Nervous System Disorders Masquerading as Acquired Neuroinflammatory Disorders: A Review

Importance

Adult-onset genetic disorders may present with clinical and magnetic resonance imaging (MRI) features suggestive of acquired inflammatory diseases. An ever-growing number of potentially treatable adult-onset genetic neuroinflammatory disorders have been described in the past few years that need to be rapidly identified.

Observations

Adult-onset acquired neuroinflammatory disorders encompass a large group of central nervous system (CNS) diseases with varying presentation, MRI characteristics, and course, among which the most common is multiple sclerosis. Despite recent progress, including the discovery of specific autoantibodies, a significant number of adult-onset neuroinflammatory disorders with progressive or relapsing course still remain without a definite diagnosis. In addition, some patients with genetic disorders such as leukodystrophies, hemophagocytic lymphohistiocytosis, or genetic vasculopathies can mimic acquired neuroinflammatory disorders. These genetic disorders, initially described in pediatric populations, are increasingly detected in adulthood thanks to recent progress in molecular genetics and the larger availability of high-throughput sequencing technologies.

Conclusions and Relevance

Genetic adult-onset neuroinflammatory diseases are at the border between primary CNS inflammatory diseases and systemic disorders with multiorgan involvement and predominantly neurologic manifestations. Neurologists must be aware of the main clues and red flags so they can confirm a diagnosis early, when some of these genetic disorders can be successfully treated.

Neurosarcoidosis: an update on diagnosis and therapy

INTRODUCTION

Clinically overt granulomatous involvement of the nervous system (i.e., neurosarcoidosis) can be seen in up to 10% of patients with sarcoidosis. Establishing a diagnosis of neurosarcoidosis is often challenging due to the heterogeneity of clinical presentations that are sometimes non-specific, and inaccessibility of tissue confirmation. Recommended treatments are based on expert opinions that are derived from clinical experience and limited data from retrospective studies, as data from randomized controlled studies are limited.

AREA COVERED

In this article, we comprehensively review all available literature on epidemiology, clinical presentations, diagnosis, treatment, and outcomes of neurosarcoidosis. We also offer our opinions on diagnostic approach and treatment strategy.

EXPERT OPINION

Given the invasive nature and the limited sensitivity of biopsy of the nervous system, diagnosis of neurosarcoidosis is usually made when ancillary tests (such as magnetic resonance imaging and cerebrospinal fluid analysis) are compatible, and alternative diagnoses are reasonably excluded in patients with established extraneural sarcoidosis. Several factors must be taken into consideration to formulate the initial treatment strategy, including the extent of the disease, severity, functional impairment, comorbidities and patient's preference. In addition, treatment regimen of neurosarcoidosis should be formulated with an emphasis on long-term strategy.

Neurosarcoidosis presenting as longitudinally extensive myelitis: Diagnostic assessment, differential diagnosis, and therapeutic approach

Neurosarcoidosis is an uncommon and multiform clinical entity. Its presentation as an isolated longitudinal extensive transverse myelitis (LETM) is rare and challenging to identify. We report a case of LETM in a 60-year-old patient with no significant systemic symptoms nor relevant medical history. The peculiar spinal magnetic resonance imaging finding characterized by a posterior and central canal subpial contrast enhancement, the so-called “trident sign,” together with chest computed tomography scan and lymph node biopsy led to the diagnosis of sarcoidosis. We also discuss the main differential diagnoses of LETM and therapeutic options for sarcoidosis-related myelitis.

Rare case of sudden onset sensorineural hearing loss in a patient diagnosed with sarcoidosis

We report the case of a woman in her 30s who was referred to the ear, nose and throat department with sudden onset left-sided sensorineural hearing loss (SNHL), left anterior uveitis and erythematous lower limb lesions with bilateral pitting oedema. Based on her symptoms, an underlying inflammatory systemic disease was suspected. Autoantibodies were negative but an X-ray and high-resolution CT scan of the chest were suggestive of sarcoidosis, which was confirmed on endoscopic bronchial biopsy. Following treatment with a course of oral steroids, the patient's hearing has improved but she still suffers from episodes of uveitis. While immune-mediated inner ear disorders are a recognised cause of SNHL, sarcoidosis is a very rare cause. This case demonstrates the importance of screening for systemic autoimmune aetiology in SNHL and highlights the importance of an effective multidisciplinary team in the diagnosis and management of these patients.

Clinical Features, Histopathology and Differential Diagnosis of Sarcoidosis

Sarcoidosis is a chameleon disease of unknown etiology, characterized by the growth of non-necrotizing and non-caseating granulomas and manifesting with clinical pictures that vary on the basis of the organs that are mainly affected. Lungs and intrathoracic lymph nodes are the sites that are most often involved, but virtually no organ is spared from this disease. Histopathology is distinctive but not pathognomonic, since the findings can be found also in other granulomatous disorders. The knowledge of these findings is important because it could be helpful to differentiate sarcoidosis from the other granulomatous-related diseases. This review aims at illustrating the main clinical and histopathological findings that could help clinicians in their routine clinical practice.

Neurosarcoidosis Presenting as Young-Onset Chronic Headache: A Case Report

Sarcoidosis causes granulomatous inflammation in multiple organ systems. Lungs are the most commonly affected organs. In 50% of the cases with lung involvement, other organs are also involved. The central nervous system is one of the rarer organ systems involved - comprising 5-15% of all the cases. Neurological involvement, when present, can affect virtually every part of the central and peripheral nervous system. We present an interesting case of a 30-year-old nonalcoholic, nonsmoker man who presented with a chronic headache of 6 years. He had a recent swaying of the body for 6 months and mild forgetfulness for 4 months. The patient had 2 episodes of facial nerve palsy in the past - which had responded to the treatment of Bell's palsy; however, the patient had some residual findings on presentation. While CSF findings suggested meningeal tuberculosis, the radiological evidence and biopsy confirmed the diagnosis of neurosarcoidosis. On follow-up after 6 weeks of steroid therapy, the patient displayed a marked improvement in headache, cognitive function, and a good response on imaging studies. Our case emphasizes that neurosarcoidosis should be considered in the differential diagnosis of chronic headaches and recurrent facial nerve palsy despite being very rare.

Rare presentation of sarcoidosis with optic neuropathy and third nerve palsy

Sarcoidosis is a systemic, idiopathic and granulomatous disease, which most commonly affects the skin, lungs and lymph nodes but can affect virtually any organ. Neurosarcoidosis can be the presenting or the only clinical manifestation accounting for 5%-15% of sarcoid diagnoses. In contrast to uveitis which is the most common ophthalmic manifestation, neuro-ophthalmic signs are uncommon in sarcoidosis. Optic neuropathy is the most common neuro-ophthalmic sign (70% in one series). Sarcoid-related optic neuropathy commonly presents with a picture similar to optic neuritis. Less commonly, optic nerve involvement occurs secondary to compressive lesions, or from direct granulomatous infiltration. Neuroimaging is crucial to identify the location of the lesion. We describe a case of sarcoid-related compressive optic neuropathy and third nerve palsy and highlight the challenging nature of neurosarcoidosis in a patient without a prior diagnosis of the disease.

Association between neurosarcoidosis with autonomic dysfunction and anti-ganglionic acetylcholine receptor antibodies

OBJECTIVE

To determine whether autonomic dysfunction in neurosarcoidosis is associated with anti-ganglionic acetylcholine receptor (gAChR) antibodies, which are detected in autoimmune autonomic ganglionopathy.

METHODS

We retrospectively extracted cases of sarcoidosis from 1787 serum samples of 1,381 patients between 2012 and 2018. Anti-gAChR antibodies against the α3 and β4 subunit were measured by luciferase immunoprecipitation to confirm the clinical features of each case. We summarized literature reviews of neurosarcoidosis with severe dysautonomia to identify relevant clinical features and outcomes.

RESULTS

We extracted three new cases of neurosarcoidosis with severe dysautonomia, among which two were positive for anti-gAChR antibodies: Case 1 was positive for antibodies against the β4 subunit, and Case 2 was positive for antibodies against both the α3 and β4 subunits. We reviewed the cases of 15 patients with neurosarcoidosis and severe dysautonomia, including the three cases presented herein. Orthostatic hypotension and orthostatic intolerance were the most common symptoms. Among the various types of neuropathy, small fiber neuropathy (SFN) was the most prevalent, with seven of nine cases exhibiting definite SFN. Six of eight cases had impaired postganglionic fibers, of which the present three cases revealed abnormality of 123I-MIBG myocardial scintigraphy. Of the 11 cases, 10 were responsive to immunotherapy, except one seropositive case (Case 2).

CONCLUSIONS

The presence of gAChR antibodies may constitute one of the mechanisms by which dysautonomia arises in neurosarcoidosis.

Aseptic meningitis and hydrocephalus secondary to neurosarcoidosis

A 53-year-old woman presented to hospital with gait instability, urinary incontinence and confusion. She had a 4-month history of headache, blurred vision, personality change and memory problems. Magnetic Resonance Imaging of the brain after contrast application showed tectal plate and occipital enhancement, as well as a known hydrocephalus. Cerebrospinal fluid showed aseptic meningitis with no evidence of clonal expansion. After further imaging that showed generalised lymphadenopathy and subsequent tissue biopsy that showed granulomatous lymphadenitis, she was diagnosed with neurosarcoidosis. She was treated with steroids which resulted in immediate cognitive and motor improvements as well as resolution of her urinary incontinence. We discuss the features of this case that pointed towards neoplastic, infective and other autoimmune aetiologies. We describe how they were excluded and provide the rationale for our treatment. This case demonstrates an important sequela sarcoidosis, and we conclude by recommending a multidisciplinary approach towards its diagnosis and management.

Challenging Mimickers in the Diagnosis of Sarcoidosis: A Case Study

Sarcoidosis is a systemic granulomatous disease of unknown cause characterized by a wide variety of presentations. Its diagnosis is based on three major criteria: a clinical presentation compatible with sarcoidosis, the presence of non-necrotizing granulomatous inflammation in one or more tissue samples, and the exclusion of alternative causes of granulomatous disease. Many conditions may mimic a sarcoid-like granulomatous reaction. These conditions include infections, neoplasms, immunodeficiencies, and drug-induced diseases. Moreover, patients with sarcoidosis are at risk of developing opportunistic infections or lymphoma. Reliably confirming the diagnosis of sarcoidosis and better identifying new events are major clinical problems in daily practice. To address such issues, we present seven emblematic cases, seen in our department, over a ten-year period along with a literature review about case reports of conditions misdiagnosed as sarcoidosis.

A Study of the Clinical Profile, Radiologic Features, and Therapeutic Outcomes in Neurosarcoidosis from Two Tertiary Care Centers in Southern India

Background

Sarcoidosis is an inflammatory granulomatous disease affecting multiple organ systems. Neurological manifestations are rare and seen in approximately 5% cases of sarcoidosis. They may commonly precede the diagnosis of sarcoidosis. Since there is paucity of Indian literature on this subject, we decided to review the clinical and radiological profile, laboratory abnormalities, treatment and long-term outcomes in our patients with neurosarcoidosis (NS).

Methods

The study was done by retrospective review of medical records for all cases diagnosed as NS during the period Jan 2014-Jan 2018. These cases were classified as definite, probable, and possible NS, on the basis of established diagnostic parameters (Zajicek criteria). The follow-up record in these cases ranged from 6 months to 3 years, with special emphasis on monitoring the response to treatment and long-term disability.

Results

The cases showed varied clinical abnormalities and imaging findings. Cranial neuropathies and myelopathy were the most common clinical presentations. Optic neuritis was most common cranial neuropathy, followed by facial nerve palsy and lower cranial nerve palsies. Most common magnetic resonance imaging findings were T2 hyperintense parenchymal lesions and meningeal enhancement. There was strong correlation between baseline clinico radiological parameters and long-term outcomes, as evidenced by relatively poor prognosis seen in cases with bilateral optic neuritis, myelopathy and imaging evidence of hydrocephalus, or leptomeningitis.

Conclusion

The diagnosis of NS requires a high degree of suspicion, coupled with exclusion of alternate diagnosis. It commonly precedes the onset of systemic sarcoidosis. Central nervous system involvement in sarcoidosis is associated with poor clinical outcomes.

Diagnostic approach in multiple sclerosis with MRI: an update

Although neurological examination and medical history are the first and most important steps towards the diagnosis of multiple sclerosis (MS), MRI has taken a prominent role in the diagnostic workflow especially since the implementation of McDonald criteria. However, before applying those on MR imaging features, other diseases must be excluded and MS should be favoured as the most likely diagnosis. For the prognosis the earliest possible and correct diagnosis of MS is crucial, since increasingly effective disease modifying therapies are available for the different forms of clinical manifestation and progression. This review deals with the significance of MRI in the diagnostic workup of MS with special regard to daily clinical practice. The recommended MRI protocols for baseline and follow-up examinations are summarized and typical MS lesion patterns ("green flags") in four defined CNS compartments are introduced. Pivotal is the recognition of neurological aspects as well as imaging findings atypical for MS ("red flags"). In addition, routinely assessment of Aquaporin-4-IgG antibodies specific for neuromyelitis optica spectrum disorders (NMOSD) as well as the knowledge of associated lesion patterns on MRI is recommended. Mistaken identity of such lesions with MS and consecutive implementation of disease modifying therapies for MS can worsen the course of NMOSD.

Cochlear Implant Outcomes in Patients with Neurosarcoidosis

INTRODUCTION

Audiovestibular symptoms are rare in sarcoidosis, but they may also be the first manifestation of the disease. Sudden or progressive bilateral hearing loss is usually associated with vestibular impairment. The mechanism of hearing loss remains unclear, but clinical presentation and magnetic resonance imaging suggest a retrocochlear site for the lesion in most patients. Several cases of hearing recovery after corticosteroid treatment have been reported. In patients with severe or profound hearing loss, the benefit of cochlear implantation is challenging to predict in the case of auditory neuropathy and is rarely described. We present a case series of cochlear implantation in patients with documented neurosarcoidosis.

RESULTS

Seven cases of cochlear implantation in 4 patients with neurosarcoidosis are reported. All of the patients showed a great improvement very quickly in both quiet and noise. Speech performance remained stable over time with a follow-up ranging from 4 to 11 years, even in patients who had disease exacerbation.

CONCLUSION

Cochlear implantation is possible in deaf patients with neurosarcoidosis. The excellent benefit obtained in our patients suggests a particular type of neuropathy, but endocochlear involvement cannot be entirely ruled out.

Infliximab for relapsing neurosarcoidosis recurring after kidney transplantation: a case report

Neurological involvement of sarcoidosis is a rare condition, and its occurrence in the context of transplantation is exceptional. Moreover, treatment can be challenging. We report the unusual case of a patient transplanted with a kidney for end-stage renal disease secondary to sarcoidosis who experienced a neurological recurrence of the disease under immunosuppressive treatment, translating in behavioural aggressiveness, social withdrawal and weight loss. He relapsed thrice under corticosteroids but responded finally to infliximab. This case highlights the potential of sarcoidosis to recur neurologically after kidney transplantation despite immunosuppressive treatment. Also, treatment of relapsing neurosarcoidosis can be challenging and may benefit from TNF-α blockers.

Sarcoidosis: A Clinical Overview from Symptoms to Diagnosis

Sarcoidosis is a multi-system disease of unknown etiology characterized by the formation of granulomas in various organs. It affects people of all ethnic backgrounds and occurs at any time of life but is more frequent in African Americans and Scandinavians and in adults between 30 and 50 years of age. Sarcoidosis can affect any organ with a frequency varying according to ethnicity, sex and age. Intrathoracic involvement occurs in 90% of patients with symmetrical bilateral hilar adenopathy and/or diffuse lung micronodules, mainly along the lymphatic structures which are the most affected system. Among extrapulmonary manifestations, skin lesions, uveitis, liver or splenic involvement, peripheral and abdominal lymphadenopathy and peripheral arthritis are the most frequent with a prevalence of 25-50%. Finally, cardiac and neurological manifestations which can be the initial manifestation of sarcoidosis, as can be bilateral parotitis, nasosinusal or laryngeal signs, hypercalcemia and renal dysfunction, affect less than 10% of patients. The diagnosis is not standardized but is based on three major criteria: a compatible clinical and/or radiological presentation, the histological evidence of non-necrotizing granulomatous inflammation in one or more tissues and the exclusion of alternative causes of granulomatous disease. Certain clinical features are considered to be highly specific of the disease (e.g., Löfgren's syndrome, lupus pernio, Heerfordt's syndrome) and do not require histological confirmation. New diagnostic guidelines were recently published. Specific clinical criteria have been developed for the diagnosis of cardiac, neurological and ocular sarcoidosis. This article focuses on the clinical presentation and the common differentials that need to be considered when appropriate.

Overcoming the Elusiveness of Neurosarcoidosis: Learning from Five Complex Cases

The involvement of the central nervous system in sarcoidosis can manifest with a variety of neurological symptoms, and most of them can be nonspecific. The diagnosis of neurosarcoidosis (NS) can therefore be very challenging without a tissue biopsy. Both computed tomography (CT) and magnetic resonance imaging (MRI) are important imaging modalities in the diagnosis of NS, and MRI is the modality of choice due to its superior soft-tissue contrast resolution. We present a case series of NS with interesting neuroimaging features, complex neurological presentations, and clinical courses. We identify five cases presenting with clinically isolated neurosarcoidosis (CINS) without any other signs or symptoms of systemic disease which were diagnosed as NS on biopsy. In the first case, we describe a patient with an intramedullary cervical spinal cord lesion. In the second case we describe a patient presenting with inflammatory changes and enhancement in the orbit. The third case demonstrates a lesion with calcification around the region of the foramen of Monro. The fourth case shows multiple ring-enhancing lesions. Lastly, the fifth case exhibits unusual findings with both optic neuritis and a cerebellar nodule. We aim to describe the complicated clinical course with neurological workup, neuro-imaging, and eventual diagnosis and treatment of these challenging cases to highlight the variable presentations of NS. This case series will remind clinicians that NS should always be in the differential diagnosis when a patient presents with nonspecific neurological symptoms with unusual neuroimaging findings.

Neurosarcoidosis with hydrocephalus as a first presenting sign: a unique case report

There is a possible relationship with cerebral ischemic events and neurosarcoidosis. It should be considered in the differential diagnosis in a case of unexplained hydrocephalus, vascular white matter lesions and vasculitis related findings.

A multi-center case series of sarcoid optic neuropathy

OBJECTIVE

The diagnosis of sarcoid optic neuropathy is time-sensitive, as delayed treatment risks irreversible vision loss. We sought to analyze its characteristics and outcomes.

METHODS

We performed a multi-center retrospective study of sarcoid optic neuropathy among 5 USA medical centers. Inclusion criteria were: 1) clinical optic neuropathy; 2) optic nerve/sheath enhancement on neuroimaging; 3) pathological confirmation of systemic or nervous system sarcoidosis.

RESULTS

Fifty-one patients were included. The median onset age of sarcoid optic neuropathy was 50 years (range, 17-70 years) and 71% were female. The median visual acuity at nadir in the most affected eye was 20/80 (range, 20/20 to no-light-perception). Thirty-four of 50 (68%) patients had radiologic evidence of other nervous system involvement and 20 (39%) patients had symptoms/signs of other cranial nerve dysfunction. Cerebrospinal fluid analysis revealed an elevated white blood cell count in 22 of 31 (71%) patients (median: 14/μL; range: 1-643/μL). Pathologic confirmation of sarcoidosis was by biopsy of systemic/pulmonary site, 34 (67%); optic nerve/sheath, 9 (18%); or other nervous system region, 8 (16%). Forty patients improved with treatment (78%), 98% receiving corticosteroids and 65% receiving steroid-sparing immunosuppressants, yet 11/46 patients (24%) had a visual acuity of 20/200 or worse at last follow-up.

CONCLUSIONS

Sarcoid optic neuropathy frequently occurs with other clinical and radiologic abnormalities caused by neurosarcoidosis and diagnostic confirmation occasionally requires optic nerve/sheath biopsy. Improvement with treatment is common but most patients have some residual visual disability. Improved recognition and a more expeditious diagnosis and treatment may spare patients from permanent vision loss.

FLT-PET for the assessment of systemic sarcoidosis including cardiac and CNS involvement: a prospective study with comparison to FDG-PET

BACKGROUND

2-deoxy-2-[18F]fluoro-D-glucose's (FDG) biodistribution limits the evaluation of cardiac sarcoidosis (CS) and neurosarcoidosis (NS). While protocols for cardiac suppression exist, they can be inconvenient for patients and lead to incomplete cardiac suppression in many cases. Furthermore, FDG PET is limited in the detection of neurosarcoidosis due to an inability to suppress high level of physiological uptake within the brain. 3'-deoxy-3'-[¹⁸F]fluorothymidine (FLT) has been shown to accumulate in sarcoidosis lesions and this tracer lacks significant physiological myocardial and brain uptake, suggesting that this tracer may be useful for the assessment of sarcoidosis, including CS and NS, without the need for patient preparation. This prospective pilot study examined the performance of FLT vs FDG PET for systemic sarcoidosis, including cardiac and neural involvement.

MATERIALS AND METHODS

Fourteen subjects with sarcoidosis were prospectively recruited and imaged with FDG- and FLT-PET. Two blinded, experienced readers independently reviewed the FLT-PET and FDG-PET images. Lesion distribution was compared between FLT and FDG. Agreement between FLT- and FDG-PET was determined using Cohen's kappa and the intra-class correlation coefficient. Inter-observer variability of FLT and FDG-PET was assessed.

RESULTS

Twelve subjects had CS as per Heart Rhythm Society criteria and 1 had NS. FLT-PET was positive in 12 (86%), and FDG-PET in 11 (79%), with cardiac uptake present in 6 (50%) and 7 (58%) of subjects with CS, respectively. The subject with NS demonstrated uptake on both FLT and FDG-PET, with more lesions on FLT. There were no significant differences in the anatomical distribution of lesions between FLT and FDG. SUVs were significantly (p < 0.001) higher for FDG than FLT (5.8 ± 3.0 vs 2.3 ± 1.1, respectively), but not (p = 0.90) after adjusting for blood pool activity (2.8 ± 1.4 vs 2.8 ± 1.1, respectively). Agreement between FLT- and FDG-PET was good to excellent for the diagnosis of sarcoidosis, lung involvement, CS, and NS (κ = 0.76, 0.69, 0.86, and 1.0, respectively). Inter-observer agreement for FLT was excellent for diagnosing sarcoidosis, CS and NS (κ = 0.81, 0.85, and 1.0, respectively) and comparable to that of FDG.

CONCLUSIONS

FLT-PET may be useful for the assessment of systemic sarcoidosis, as well as cardiac and neural involvement.

Catch the rainbow: Prognostic factor of sarcoidosis

Sarcoidosis is a systemic, chronic, inflammatory disease characterized by noncaseating granuloma formations. The fact that the etiopathogenesis of the disease has not been elucidated yet brings it many theories and assumptions. Being a systemic disease and ability to involve many organs and systems, it attracts the attention of physicians from different branches. In addition to lung involvement, skin, eye, heart, and locomotor system involvement is an important clinical finding. Sarcoidosis may present with very different clinical presentations, and therefore, it is one of the important "imitators" in the medical literature. I like sarcoidosis as a "rainbow," it is a disease that contains the characteristics of many diseases. Different clinical, radiological, and laboratory prognostic factors (lupus pernio, chronic uveitis, late-onset disease, chronic hypercalcemia, nephrocalcinosis, Afro-American race, progressive pulmonary sarcoidosis, radiologic Stage 4, bone involvement, neurosarcoidosis, cardiac involvement, and chronic respiratory failure) have been defined in this "rainbow." Early identification of these factors plays an important role in the determination of treatment strategies, morbidity, and mortality of the disease. In this article, clinical, genetic, laboratory, and radiological factors that determine the prognosis of sarcoidosis are discussed in light of the latest data in the literature.

Biomarkers in the Diagnosis and Prognosis of Sarcoidosis: Current Use and Future Prospects

Sarcoidosis is a heterogeneous disease in terms of presentation, duration, and severity. Due to this heterogeneity, it is difficult to align treatment decisions. Biomarkers have proved to be useful for the diagnosis and prognosis of many diseases, and over the years, many biomarkers have been proposed to facilitate diagnosis, prognosis, and treatment decisions. Unfortunately, the ideal biomarker for sarcoidosis has not yet been discovered. The most commonly used biomarkers are serum and bronchoalveolar lavage biomarkers, but these lack the necessary specificity and sensitivity. In sarcoidosis, therefore, a combination of these biomarkers is often used to establish a proper diagnosis or detect possible progression. Other potential biomarkers include imaging tools and cell signaling pathways. Fluor-18-deoxyglucose positron emission tomography and high-resolution computed tomography have been proven to be more sensitive for the diagnosis and prognosis of both pulmonary and cardiac sarcoidosis than the serum biomarkers ACE and sIL-2R. There is an upcoming role for exploration of signaling pathways in sarcoidosis pathogenesis. The JAK/STAT and mTOR pathways in particular have been investigated because of their role in granuloma formation. The activation of these signaling pathways also proved to be a specific biomarker for the prognosis of sarcoidosis. Furthermore, both imaging and cell signaling biomarkers also enable patients who might benefit from a particular type of treatment to be distinguished from those who will not. In conclusion, the diagnostic and prognostic path of sarcoidosis involves many different types of existing and new biomarker. Research addressing biomarkers and disease pathology is ongoing in order to find the ideal sensitive and specific biomarker for this disease.

Neurosarcoidosis Presentation as Adipsic Diabetes Insipidus Secondary to a Pituitary Stalk Lesion and Association with Anti-NMDA Receptor Antibodies

Sarcoidosis is a multisystemic inflammatory disease of unknown cause. It is characterized by the presence of noncaseating granuloma on a biopsy specimen. Clinical presentation varies across case report series with myriad of symptoms ranging from fever, respiratory symptoms, and skin lesions, or atypical symptoms like heart block or neurological symptoms. Hence, we report the case of a 22-year-old woman with encephalitis, a pituitary mass, and adipsic diabetes insipidus. The diagnostic approach did not end on the biopsy of the lesion, which reported noncaseating granulomas; on the contrary, it was the beginning of a path to exclude other causes of the central nervous system granulomas that ended with the diagnosis of the isolated central nervous system sarcoidosis. Also, we report the first proven association between anti-NMDA receptor antibodies and sarcoidosis.

[A patient with neurosarcoidosis presenting with easy falling and dysphagia]

A 68-year-old woman was referred to our hospital for progressive dizziness, gait disturbances and weight loss for 18 months. The patient was alert and showed dysphagia and a marked tendency to fall backward. Electronystagmography showed bilateral vestibular dysfunction and audiometry showed right sensorineural hearing disturbance. Cerebrospinal fluid exam showed mononuclear pleocytosis and elevated protein levels. On ¹⁸F-FDG PET/CT, abnormal uptake was observed in the mediastinal lymph nodes, from which biopsy specimens were obtained. Histological findings showed non-caseous granuloma and a diagnosis of bilateral vestibulocochlear, glossopharyngeal and vagal nerve palsies due to neurosarcoidosis was made. Steroid therapy resulted in improvement in her clinical symptoms. Neurosarcoidosis should be included in the differential diagnosis of patients showing progressive easy falling and dysphagia.

Neurosarcoidosis: Longitudinal experience in a single-center, academic healthcare system

OBJECTIVE

To characterize patients with neurosarcoidosis within the University of Utah healthcare system, including demographics, clinical characteristics, treatment, and long-term outcomes.

METHODS

We describe the clinical features and outcomes of patients with neurosarcoidosis within the University of Utah healthcare system (a large referral center for 10% of the continental United States by land mass). Patients were selected who met the following criteria: (1) at least one International Classification of Diseases Clinical Modification, 9th revision code 135 or International Classification of Diseases Clinical Modification, 10th revision code D86* (sarcoidosis) and (2) at least one outpatient visit with a University of Utah clinician in the Neurology Department within the University of Utah electronic health record.

RESULTS

We identified 56 patients meeting the study criteria. Thirty-five patients (63%) were women, and most patients (84%) were white. Twelve patients (22%) met the criteria for definite neurosarcoidosis, 36 patients (64%) were diagnosed with probable neurosarcoidosis, and 8 patients (14%) were diagnosed with possible neurosarcoidosis. A total of 8 medications were used for the treatment of neurosarcoidosis. Prednisone was the first-line treatment in 51 patients (91%). Infliximab was the most effective therapy, with 87% of patients remaining stable or improving on infliximab. Treatment response for methotrexate and azathioprine was mixed, and mycophenolate mofetil and rituximab were the least effective treatments in this cohort.

CONCLUSIONS

This is a comprehensive characterization of neurosarcoidosis within a single healthcare system at the University of Utah that reports long-term response to treatment and outcomes of patients with neurosarcoidosis. Our results suggest the use of infliximab as a first-line therapy for neurosarcoidosis.

Analysis of soluble interleukin-2 receptor as CSF biomarker for neurosarcoidosis

OBJECTIVE

To systematically analyze soluble interleukin-2 receptor (sIL-2R) in CSF as a diagnostic and disease activity biomarker in patients with sarcoidosis involving the CNS (neurosarcoidosis).

METHODS

sIL-2R was determined by chemiluminescent immunoassays in CSF/serum samples from patients with neurosarcoidosis (n = 23), MS (n = 19), neurotuberculosis (n = 8), viral (n = 18) and bacterial (n = 9) meningitis, cerebral lymphoma (n = 15), Guillain-Barré syndrome (n = 8), and 115 patients with noninflammatory neurologic diseases (NINDs) as controls. The sIL-2R index was calculated by dividing the CSF/serum sIL-2R quotient (Q_sIL-2R) through the CSF/serum albumin quotient (Q_Alb). sIL-2R quotient diagrams were established by plotting Q_sIL-2R against Q_Alb. sIL-2R levels were correlated with clinical, MRI, and CSF disease activity markers of neurosarcoidosis.

RESULTS

Patients with neurosarcoidosis had higher CSF sIL-2R, Q_sIL-2R, and sIL-2R index values than patients with NINDs (p < 0.0001 for all pairwise group comparisons). sIL-2R quotient diagrams demonstrated an intrathecal sIL-2R synthesis in >50% of neurosarcoidosis samples. Similar findings were observed in viral/bacterial meningitis, CNS lymphoma, and, most pronounced, in neurotuberculosis, but not in patients with MS. CSF sIL-2R parameters were associated with clinical disease activity, leptomeningeal gadolinium enhancement, and the CSF white cell count in patients with neurosarcoidosis.

CONCLUSIONS

CSF sIL-2R parameters are elevated in patients with neurosarcoidosis, but this finding is not specific for neurosarcoidosis. Nevertheless, CSF sIL-2R parameters may help distinguishing neurosarcoidosis from MS and are associated with clinical, radiologic, and CSF disease activity markers of neurosarcoidosis.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that CSF sIL-2R parameters distinguish neurosarcoidosis from NINDs and MS.

Distinguishing neurosarcoidosis from multiple sclerosis based on CSF analysis: A retrospective study

OBJECTIVE

To characterize a cohort of patients with neurosarcoidosis with particular focus on CSF analysis and to investigate whether CSF values could help in distinguishing it from multiple sclerosis (MS).

METHODS

This retrospective cohort study enrolled 85 patients with a diagnosis of neurosarcoidosis (possible, probable, or definite). CSF total protein, white cell count, and angiotensin-converting enzyme levels were measured. CSF and serum oligoclonal immunoglobulin G (IgG) patterns were analyzed with the use of odds ratios and binary logistic regression.

RESULTS

Eighty patients had a probable (nonneural positive histology) or definite (neural positive histology) diagnosis of neurosarcoidosis. Most frequent findings on MRI were leptomeningeal enhancement (35%) and white matter and spinal cord involvement (30% and 23%). PET scan showed avid areas in 74% of cases. CSF analysis frequently showed lymphocytosis (63%) and elevated protein (62%), but CSF-selective oligoclonal bands were rare (3%). Serum ACE levels were elevated in 51% of patients but in only 14% of those with isolated neurosarcoidosis. Elevated CSF ACE was not found in any patient.

CONCLUSIONS

Large elevations in total protein, white cell count, and serum ACE occur in neurosarcoidosis but are rare in MS. The diagnostic use of these tests is, however, limited because minimal changes may occur in both. MS clinical mimics in neurosarcoidosis are not common, and intrathecal synthesis of oligoclonal IgG is a powerful discriminator because it is rare in neurosarcoidosis but occurs in 95% to 98% cases of MS. We suggest caution in making a diagnosis of neurosarcoidosis when intrathecal oligoclonal IgG synthesis is found.

Neurosarcoidosis Presenting as Isolated Bilateral Cerebellopontine Angle Tumors: Case Report and Review of the Literature

OBJECTIVES

To describe a unique case of isolated bilateral sarcoidosis of the cerebellopontine angle as well as the related imaging in the case. To conduct a literature review of the published articles regarding sarcoidosis of the cerebellopontine angle.

DATA SOURCES

Representative case report from a single institution as well as PubMed and Scopus database searches.

METHODS

In addition to a retrospective review, all published case reports and case series of sarcoidosis involving the cerebellopontine angle from 1960 to July 2018 in the English language were reviewed. Demographic data, presenting symptoms, and outcomes were collected.

RESULTS

We identified 8 total cases with pertinent clinical information that were included.

CONCLUSIONS

Isolated neurosarcoidosis of the cerebellopontine angle is an exceptionally rare phenomenon that, on history and imaging, presents similar to more common retrocochlear pathologies. Surgery may be required in large lesions unresponsive to traditional medical therapy with immunosuppression.

[Neuromyelitis optica and neuromyelitis optica spectrum disorders]

The review is devoted to up-to-date data on epidemiology, aspects of the pathogenesis of neuromyelitis optica (NMO) and neuromyelitis optica spectrum disorders (NMOSD). The authors consider a role of myelin oligodendrocyte glycoprotein immunoglobulin G (MOG-IgG) in the syndromes phenotypically similar to NMO and NMOSD. Special attention is drawn to the methods of MOG-IgG antibodies detection and indications for testing. The approaches and management for treatment and prevention of NMO relapses, risks of complications during pregnancy and immediately after delivery, as well as methods for their prevention and treatment, are described.

Leukocyte profiles in blood and CSF distinguish neurosarcoidosis from multiple sclerosis

Distinguishing neurosarcoidosis (NS) from multiple sclerosis (MS) remains challenging and available parameters lack discriminatory power. Comprehensive flow cytometry data of blood and CSF leukocytes of patients with NS (n = 24), MS (n = 49) and idiopathic intracranial hypertension (IIH, n = 52) were analyzed by machine learning algorithms. NS featured a specific immune cell pattern with increased activated CD4+ T cells in CSF and increased plasma cells in blood. Combining blood and CSF parameters improved the differentiation. We thereby identify and independently validate a multi-dimensional model of blood and CSF supporting the difficult differential diagnosis between NS and MS.

Pituitary Stalk Enlargement in Adults

Pathologies involving the pituitary stalk (PS) are generally revealed by the presence of diabetes insipidus. The availability of MRI provides a major diagnostic contribution by enabling the visualization of the site of the culprit lesion, especially when it is small. However, when only an enlarged PS is found, the etiological workup may be difficult, particularly because the biopsy of the stalk is difficult, harmful and often not contributive. The pathological proof of the etiology thus needs to be obtained indirectly. The aim of this article was to provide an accurate review of the literature about PS enlargement in adults describing the differences between the numerous etiologies involved and consequent different diagnostic approaches. The etiological diagnostic procedure begins with the search for possible other lesions suggestive of histiocytosis, sarcoidosis, tuberculosis or other etiologies elsewhere in the body that could be more easily biopsied. We usually perform neck, thorax, abdomen, and pelvis CT scan; positron emission tomography scan; bone scan; or other imaging methods when we suspect generalized lesions. Measurement of serum markers such as human chorionic gonadotropin, alpha-fetoprotein, angiotensin converting enzyme, and IgG4 may also be helpful. Obviously, in the presence of an underlying carcinoma (particularly breast or bronchopulmonary), one must first consider a metastasis located in the PS. In the case of an isolated PS enlargement, simple monitoring, without histological proof, can be proposed (by repeating MRI at 3-6 months) with the hypothesis of a germinoma (particularly in a teenager or a young adult) that, by increasing in size, necessitates a biopsy. In contrast, a spontaneous diminution of the lesion is suggestive of infundibulo-neurohypophysitis. We prefer not to initiate steroid therapy to monitor the spontaneous course when a watch-and-see attitude is preferred. However, in many cases, the etiological diagnosis remains uncertain, requiring either close monitoring of the lesion or, in exceptional situations, trying to obtain definitive pathological evidence by a biopsy, which, unfortunately, is in most cases performed by the transcranial route. If a simple surveillance is chosen, it has to be very prolonged (annual surveillance). Indeed, progression of histiocytosis or germinoma may be delayed.