Extradural Dumbbell-Shaped Tuberculoma Masquerading as Nerve Sheath Tumor: Case Report and Review of Literature.

BACKGROUND: Spinal tuberculosis has been listed as a rare cause of neuroforaminal widening with only 2 previous reports in the literature. Here, we report the third case of an extradural tuberculoma extending through and expanding the neural foramen closely masquerading as a nerve sheath tumor including, to the best of our knowledge, the first description of magnetic resonance imaging, operative, and histopathology findings. CASE DESCRIPTION: A 65-year-old Nigerian man presented with signs and symptoms of worsening thoracic myeloradiculopathy for the past month. Imaging found an extradural dumbbell-shaped lesion involving the spinal canal, neural foramen, and paraspinal area with a combination of solid and cystic components causing bony remodeling of the pedicle and vertebral body, as well as enlargement of the neural foramen. Surgery was performed to resect the mass, and pathology postoperatively demonstrated caseating granulomas, rare thin elongated organisms on Ziehl-Neelsen staining, and involvement of nerve fascicles. CONCLUSIONS: This case illustrates that a tuberculoma can have many of the features of a benign neoplasm, such as encapsulation, appearance of a slow rate of growth, and development of necrosis or even cystic degeneration. With the specific findings of entrapped nerve fascicles, we postulate that the lesion represents a nerve sheath tuberculoma rather than spinal tuberculosis of the pedicle or posterior elements. Furthermore, only a lesion of the nerve sheath would have the characteristic dumbbell appearance as it extends through the foramen.

Hemorrhagic intracranial follicular dendritic cell sarcoma: A case report.

BACKGROUND: Follicular dendritic cell (FDC) sarcoma is an extremely rare neoplasm, which has only been reported once in the literature with an intracranial occurrence. Neither hemorrhagic presentation of an intracranial instance of FDC sarcoma nor its rapid recurrence has yet been published in the literature. CASE DESCRIPTION: We report the case of a 61-year-old female who presented with confusion and headaches secondary to a right frontal hemorrhagic lesion, and her subsequent presentations for recurrence of the lesion and finding of a new intracranial lesion. Immunohistopathologic analysis confirmed the diagnosis based on immunoreactivity for clusterin and CD 35. CONCLUSION: As demonstrated in this case report, the presentation and progression of primary intracranial follicular dendritic cell sarcoma can often be misleading, and consideration for this rare entity should be made in cases of hemorrhagic dural-based lesions without a primary source of malignancy.

Glioblastoma multiforme presenting with an open ring pattern of enhancement on MR imaging.

BACKGROUND: Intracerebral ring enhancing lesions can be the presentation of a variety of pathologies, including neoplasia, inflammation, and autoimmune demyelination. Use of a precise diagnostic algorithm is imperative in correctly treating these lesions and minimizing potential adverse treatment effects. CASE DESCRIPTION: A 55-year-old patient presented to the hospital with complaints of a post-concussive syndrome and a non-focal neurologic exam. Imaging revealed a lesion with an open ring enhancement pattern, minimal surrounding vasogenic edema, and minimal mass effect. Given the minimal mass effect, small size of the lesion, and nonfocal neurological exam, we elected to pursue a comprehensive noninvasive neurologic workup because our differential ranged from inflammatory/infectious to neoplasm. Over the next 8 weeks, the patient's condition worsened, and repeat imaging showed marked enlargement of the lesion with a now closed ring pattern of enhancement with satellite lesions and a magnetic resonance (MR) spectroscopy and perfusion signature suggestive of neoplasm. The patient was taken to surgery for biopsy and debulking of the lesion. Surgical neuropathology examination revealed glioblastoma multiforme. CONCLUSION: The unique open ring enhancement pattern of this lesion on initial imaging is highly specific for a demyelinating process, however, high-grade glial neoplasms can also present with complex and irregular ring enhancement including an open ring sign. Therefore, other imaging modalities should be used, and close follow-up is warranted when the open ring sign is encountered.

Ollier disease with anaplastic astrocytoma: A review of the literature and a unique case.

BACKGROUND: Ollier disease is a rare, nonfamilial disorder that primary affects the long bones and cartilage of joints with multiple enchondromas. It is associated with a higher risk of central nervous system (CNS) malignancies; although the incidence is unknown. CASE DESCRIPTION: Here, we present the case of a 55-year-old woman who developed an anaplastic astrocytoma with a known diagnosis of Ollier disease with a survival time of over 3 years. CONCLUSION: This report draws attention to the rarity of this disease and the paucity of information regarding CNS involvement in Ollier disease, as well as reviews the current literature.

Prenatally Diagnosed Aggressive Intracranial Immature Teratoma-Clinicopathological Correlation.

OBJECTIVE: To describe clinicopathological correlation of congenital intracranial immature teratoma. METHODS: A retrospective case analysis from a tertiary medical center. RESULTS: We report a case of an intracranial immature teratoma detected prenatally at 35 weeks of gestation. The tumor showed rapid growth, causing acute hydrocephalus requiring subsequent ventriculoperitoneal shunting. Resective surgery was performed within 2 weeks after birth. The infant died at day of life 29. Histological examination revealed an immature teratoma, with high MIB1/Ki-67 proliferation index. CONCLUSION/IMPLICATIONS: Intracranial immature teratoma with high MIB1/Ki-67 proliferation index may serve as an independent poor prognostic factor.

ILAE type 3 hippocampal sclerosis in patients with anti-GAD-related epilepsy.

OBJECTIVE: To describe the neuropathologic findings and clinical course of 2 patients who underwent temporal lobectomy for medically refractive epilepsy and were later found to have high anti-glutamic acid decarboxylase (GAD) concentrations. METHODS: Small case series. RESULTS: Neuropathologic examination of both patients revealed International League Against Epilepsy (ILAE) type 3 hippocampal sclerosis. Following surgery, both developed signs and symptoms of stiff person syndrome and later cerebellar ataxia. Laboratory studies demonstrated high concentrations of anti-GAD antibodies in both patients. CONCLUSIONS: These cases suggest that ILAE type 3 hippocampal sclerosis may be immunologically related to and may exist as part of a broader anti-GAD-related neurologic syndrome in some instances.

Optimizing the skeletal muscle biopsy.

Knowledge of disorders of skeletal muscle remains of importance for the practicing pathologist. While genetic testing has proved useful in the diagnosis of many patients, especially those with the more common forms of muscular dystrophy, less common genetic myopathies, congenital myopathies, and toxic myopathies, often related to commonly used therapeutic agents such as statins, still require pathological analysis for diagnostic purposes. A contemporary pathologist may expect to be consulted about unusual familial neuromuscular disorders, autoimmune disorders, and drug-induced myopathies, often in the context of patients with multiple medical conditions that complicate the clinical and pathological analysis. A working knowledge of skeletal muscle biopsy and its clinical utility as well as its limitations is therefore important for all pathologists. Each pathologist must decide if they wish to process the biopsy in their own laboratory, or if the specimen should be sent to a reference laboratory for analysis.

Brief report: life history and neuropathology of a gifted man with Asperger syndrome.

Despite recent interest in the pathogenesis of the autism spectrum disorders (pervasive developmental disorders), neuropathological descriptions of brains of individuals with well documented clinical information and without potentially confounding symptomatology are exceptionally rare. Asperger syndrome differs from classic autism by lack of cognitive impairment or delay in expressive language acquisition. We examined the 1,570 g brain of a 63 year old otherwise healthy mathematician with an Autistic Spectrum Disorder of Asperger subtype. Except for an atypical gyral pattern and megalencephaly, we detected no specific neuropathologic abnormality. Taken together, the behavioral data and pathological findings in this case are compatible with an early neurodevelopmental process affecting multiple neuroanatomic networks, but without a convincing morphologic signature detectable with routine neuropathologic technology.

Neuropathology of Cockayne syndrome: Evidence for impaired development, premature aging, and neurodegeneration.

Global growth and development failure, premature, accelerated, pathologic aging, and neurodegeneration characterize Cockayne syndrome (CS) and the cerebro-oculo-facial-skeletal and xeroderma pigmentosum/CS syndromes which overlap CS partially in their genetic, somatic, and neuropathologic features. Mutations of CSA or CSB genes jeopardize transcription-coupled repair of damaged nuclear and mitochondrial DNA and resumption of replication and transcription. Resultant defective proteins or gene silencing eventuate in profound dwarfism and micrencephaly, cachexia, vasculopathy, and neurodegeneration. Cellular effects are highly selective. Purkinje cells may die by apoptosis and have grossly dystrophic dendrites. Neuronal death and axonal spheroids indexing neuronal pathology predominate in, but are not limited to, the cerebellum. Progressive loss of retinal, cochlear, and vestibular sensory receptors foster degeneration of ganglion cells and transneuronal brain degeneration. Some proliferating astrocytes are multinucleated and bizarre. Primary damage of oligodendrocytes and Schwann cells may - or may not - explain severe patchy myelin loss ("tigroid leukodystrophy") and segmental demyelinating peripheral neuropathy. Age-related changes are minor in the brain, although precocious severe athero- and arteriolosclerosis are responsible for occasional strokes. Vasculopathology may contribute to myelin loss and to dystrophic mineralization of neurons and vessels, especially in basal ganglia and cerebellum. Understanding the genetics, biochemical, and cellular pathophysiology of these disorders remains fragmentary.

The neuroradiological findings in a case of Revesz syndrome.

Revesz syndrome is a variant of dyskeratosis congenita characterized by aplastic anemia, retinopathy, and central nervous system abnormalities. We describe a 3-year-old boy in whom the spectrum of neuroimaging findings, including intracranial calcifications, cerebellar hypoplasia and unusual brain lesions were found by biopsy to be gliosis despite their enhancement and progression. In patients with dyskeratosis-related syndromes, non-neoplastic parenchymal brain lesions occur and gliosis should be considered in the differential diagnosis for progressive enhancing brain lesions. Should this finding be confirmed consistently in additional cases, brain biopsy could potentially be avoided.

Hydroxychloroquine-induced toxic myopathy causing respiratory failure.

Chloroquine and hydroxychloroquine (HCQ) are commonly prescribed antimalarial agents used for a variety of systemic diseases. HCQ neuromyotoxicity is a rare complication characterized by proximal muscle weakness, normal creatinine kinase levels, and characteristic ultrastructural changes on muscle biopsy of curvilinear body formation. In this report, we describe a patient with rheumatoid arthritis and respiratory failure associated with proximal myopathy secondary to HCQ. Characteristic changes on muscle biopsy were present. Patients treated with HCQ in whom proximal myopathy, neuropathy, or cardiomyopathy develop should be evaluated for possible HCQ toxicity. Clinicians should be aware of this unusual complication of antimalarials, as discontinuation of the agent may result in clinical improvement.

Identification of G-protein coupled receptor kinase 2 in paired helical filaments and neurofibrillary tangles.

G-protein coupled receptor kinases (GRKs) constitute a serine/threonine kinase family playing a major role in agonist-induced phosphorylation and desensitization of G-protein coupled receptors. Recently, GRK2 and GRK5 have been demonstrated to phosphorylate alpha-synuclein (Ser129) and other synuclein isoforms. We studied colocalization of GRK2, GRK5, alpha-synuclein, and tau in neurodegenerative disorders characterized by fibrillary tau inclusions and/or alpha-synuclein-enriched Lewy bodies. We found that Lewy bodies were negative for both GRK2 and GRK5 in Lewy body disease (LBD) and LBD mixed with Alzheimer disease (AD + LBD). Instead, GRK2 but not GRK5 colocalized with 40% to 50% of neurofibrillary tangles in AD + LBD and AD brains. In disorders with less prominent alpha-synucleinopathy, neuronal and glial fibrillary tau deposits known to contain distinct subsets of tau isoforms were also positive for GRK2. These deposits included tufted astrocytes and coiled bodies in progressive supranuclear palsy, astrocytic plaques in corticobasal degeneration, and Pick bodies in Pick disease. In addition, paired helical filaments isolated from AD and AD + LBD brains were found to immunogold-label for GRK2, suggesting that GRK2 could be a potential tau kinase associated with fibrillary tau. Our studies indicate that GRK2 is a novel component of neuronal and glial fibrillary tau deposits with no preference in tau isoform binding. GRK2 may play a role in hyperphosphorylation of tau in tauopathies.

Accreditation council for graduate medical education (ACGME) competencies in neuropathology training.

The Accreditation Council for Graduate Medical Education (ACGME) has defined 6 core competencies for all physicians: patient care; medical knowledge; practice-based learning and improvement; interpersonal and communication skills; professionalism; and systems-based practice. However, the specific wording of the descriptions often assumes that the physician is a clinician rather than a pathologist. Therefore, the American Association of Neuropathologists, Inc. asked its Professional Affairs Committee to examine the core competencies and determine how they relate to training in neuropathology. The Committee's report is presented here in 6 sections, corresponding to the 6 competencies. In each section, the ACGME definition of that particular competency is either quoted directly or, more often, modified slightly to clarify how the competency applies to neuropathology. Each of the defined competencies is then followed by possible assessment tools, selected from those recommended in the ACGME's "toolbox." Specific suggestions are given for designing tools that apply to neuropathology. Many of the suggested activities and documentation methods can be combined into efficient, carefully formulated training/evaluation exercises. Different tools may be more applicable in some training programs.

Two cases of spinal meningeal melanocytoma.

Meningeal melanocytoma is a rare pigmented tumor originating from the melanocytes that generally occurs in the posterior fossa and the spinal cord. Although it is known as a relatively benign tumor, some recurrences have been reported. We report two cases of spinal meningeal melanocytoma with immunohistochemical and ultrastructural studies. In addition, we include a summary of published cases since the first case of Limas and Tio in 1972.

Morphological and biochemical correlations of abnormal tau filaments in progressive supranuclear palsy.

Progressive supranuclear palsy (PSP) is characterized by specific filamentous tau inclusions present in 3 types of cells including oligodendrocytes (coiled bodies), astrocytes (tufted astrocytes), and neurons (neurofibrillary tangles; NFTs). To correlate the morphological features and biochemical composition of tau in the inclusions, we examined tau filament-enriched fractions isolated from selected brain regions. Frontal and cerebellar white matter manifested a predominance of coiled bodies. The isolated fractions contained straight, 14-nm-wide filaments of relatively smooth appearance. Caudate nucleus and motor cortex with numerous tufted astrocytes contained mostly straight, but irregular, 22-nm-wide filaments with jagged contours. Perirhinal cortex and hippocampus, rich in NFTs, contained 22-nm-wide filaments that were twisted at 80-nm intervals. Among the regions, those with tufted astrocytes showed the most heterogeneity in the ultrastructure of filaments. In all regions, isolated filaments were immunolabeled with PHF-1, Tau 46, and AT8. Fractions from all regions showed 2 PHF-1 immunoreactive bands of 64 and 68 kDa, while an additional band of 60 kDa was detected in NFT-enriched regions. All fractions, in varying extents, showed Tau-1-immunoreactive bands between 45-64 kDa. The results indicate that the 3 types of PSP tau inclusions vary in the ultrastructure although with some overlapping features. Neuronal and glial inclusions also vary in the biochemical profile of tau protein. These differences may depend on the metabolism of tau in the diseased oligodendrocytes, astrocytes, and neurons.

CD40-CD40L interactions induce chemokine expression by human microglia: implications for human immunodeficiency virus encephalitis and multiple sclerosis.

CD40 is a protein on microglia that is up-regulated with interferon (IFN)-gamma and is engaged by CD40L, found on CD4+ T cells, B cells, and monocytes. These interactions may be important in central nervous system inflammatory diseases. Microglia have been shown to be a source of chemokines, whose expression plays a key role in central nervous system pathologies. We examined the expression of CD40 on microglia in human immunodeficiency virus (HIV) encephalitic brain, and the effects of CD40-CD40L interactions on the expression of chemokines by cultured microglia. We found significantly increased numbers of CD40-positive microglia in HIV-infected brain tissue. Treatment of cultured microglia with IFN-gamma and CD40L increased expression of several chemokines. IFN-gamma- and CD40L-induced MCP-1 protein was mediated by activation of the ERK1/2 MAPK pathway, and Western blot analysis demonstrated phosphorylation of ERK1/2 upon stimulation of microglia. In contrast, IFN-gamma- and CD40L-induced IP-10 protein production was mediated by the p38 MAPK pathway. Our data suggest a mechanism whereby CD40L+ cells can induce microglia to secrete chemokines, amplifying inflammatory processes seen in HIV encephalitis and multiple sclerosis, and implicate CD40-CD40L interactions as a target for interventional strategies.