Mimics of Pediatric Small Vessel Primary Angiitis of the Central Nervous System.

OBJECTIVE: Small vessel primary angiitis of the central nervous system is a rare and often severe disease characterized by central nervous system-restricted inflammatory vasculitis on histopathology. Diagnosis requires brain biopsy for confirmation and is suggested prior to starting immunotherapy when feasible. However, emerging evidence suggests that other neuroinflammatory conditions may have a clinical and radiographic phenotype that mimics small vessel primary angiitis, at times with overlapping pathologic features as well. Such diagnoses, including myelin oligodendrocyte glycoprotein antibody-associated disease and central nervous system-restricted hemophagocytic lymphohistiocytosis, can be non-invasively diagnosed with serum antibody or genetic testing that would prompt different monitoring and treatment paradigms. To determine the ultimate diagnosis of patients who were suspected prior to biopsy to have small vessel primary angiitis, we reviewed the clinical, radiographic, and pathological features of a cohort of patients at a single center undergoing brain biopsy for non-oncologic indications. METHODS: Clinical data were retrospectively extracted from the medical record. Pathology and neuroimaging review was conducted. RESULTS: We identified 21 patients over a 19-year time-period, of whom 14 (66.7%) were ultimately diagnosed with entities other than small vessel primary angiitis that would have obviated the need for brain biopsy. Diagnoses included anti-myelin oligodendrocyte glycoprotein antibody associated disease (n = 9), central nervous system-restricted hemophagocytic lymphohistiocytosis (n = 3), anti-GABAA receptor encephalitis (n = 1), and Aicardi-Goutières syndrome (n = 1). INTERPRETATION: This study highlights the importance of pursuing now readily available non-invasive testing for mimicking diagnoses before performing a brain biopsy for suspected small vessel primary angiitis of the central nervous system. ANN NEUROL 2023;93:109-119.

Eosinophilic pustule smear in the diagnosis of pediatric post-transplant eosinophilic folliculitis.

Hematologic-associated eosinophilic pustular folliculitis is a subtype of eosinophilic pustular folliculitis (EPF) which develops in patients with underlying hematological malignancies after treatment with chemotherapy, bone marrow transplant (BMT), or stem cell transplant (SCT). Few cases of hematological-associated EPF have been reported in pediatric patients. Skin biopsy is considered the gold standard for diagnosis. We describe a case in which Wright staining of a pustule smear for eosinophils provided data to rapidly support a clinical diagnosis of hematologic-associated EPF.

Necrotizing enterovirus myositis in a pediatric renal transplant recipient.

BACKGROUND: Enteroviruses can cause severe infections, including viral myocarditis, meningitis, acute flaccid myelitis, and viral myositis. METHODS/RESULTS: We report a 3-year-old female renal transplant recipient who presented to a tertiary care hospital with elevated serum liver aminotransferases and subsequently developed proximal muscle pain, weakness, and respiratory distress during the first week of hospitalization. Imaging of the lower extremities revealed diffuse myositis of the proximal thigh and pelvic muscles. A muscle biopsy was obtained and revealed necrotizing myositis with immunostaining positive for enterovirus, consistent with a diagnosis of enterovirus necrotizing myositis. She had complete resolution of symptoms with steroids, intravenous immune globulin, reduced tacrolimus dose, and physical therapy. CONCLUSIONS: Enterovirus myositis should be included in the differential diagnosis for necrotizing myositis following renal transplantation in children.

Childhood lymphomatoid papulosis Type D, a rare and challenging diagnosis.

A 10-year-old female with a several-year history of pityriasis lichenoides (PL) presented with a new, asymptomatic, large, and necrotic ulcer of her right upper arm. Skin biopsy was consistent with lymphomatoid papulosis (LyP) Type D, a recently recognized subtype of LyP that is distinguished histologically by marked epidermotropism and a perivascular infiltrate of medium-sized pleomorphic lymphocytes with a cytotoxic phenotype (CD3+, CD8+). This is only the sixth reported case of LyP Type D in a child, and while the prognosis in children appears favorable, with no reports of progression to lymphoma to date, more experience in children with longer-term follow-up is needed. Our case highlights both the challenging clinical diagnosis, since in our patient the longstanding clinical presentation was indistinguishable from PL, as well as histopathologic diagnosis, which required expert opinion and consensus.

Fatal Hemoperitoneum Due to Isolated Splenic Peliosis.

ABSTRACT: Isolated splenic peliosis is an exceedingly rare condition of unclear etiology characterized by blood filled cyst-like cavities in the primary mononuclear phagocytic organ. People with splenic peliosis are typically asymptomatic. However, splenic peliosis may present as an incidental mass on imaging mimicking a neoplasm during life, or present as sudden death after hemoperitoenum when ruptured, mimicking traumatic injury. Awareness of this condition is important to forensic pathologists so as to provide an accurate cause and manner of death.

A Case Series of Acute Hemorrhagic Leukoencephalitis.

ABSTRACT: Acute hemorrhagic leukoencephalitis (AHL) is an acute, hemorrhagic demyelinating disease thought to be caused by an immune-mediated process. Acute hemorrhagic leukoencephalitis is both diagnostically challenging and fatal in the majority of cases. We present two cases of AHL unexpectedly diagnosed at autopsy. These cases demonstrate the often nonspecific and challenging nature of AHL clinical presentation, review neuropathological mimics, and emphasize the importance of considering this diagnosis in the forensic setting.

Tau deposition in young adults with drug-resistant focal epilepsy.

OBJECTIVE: To evaluate the presence of tau deposition and pathologic features of chronic traumatic encephalopathy (CTE) in young adult patients treated with focal cortical resections for drug-resistant epilepsy. METHODS: Sixty consecutive patients who had undergone surgical treatment for drug-resistant focal epilepsy between 18 and 45 years of age were identified (2010-2017). Medical records were reviewed to determine clinical factors, including history of head trauma, age at seizure onset, age at surgical resection, seizure type(s) and frequency, imaging findings, and surgical outcome. All formalin-fixed, paraffin-embedded blocks from the surgical specimens from each subject were sectioned and stained with hematoxylin and eosin and antibodies to tau (Thermo Fisher Scientific Clone AT8), and examined blindly for tau pathology, including lesions characteristic of CTE. RESULTS: The median age at resection was 29.5 years (range = 19-45). A history of head trauma was reported in 19 patients. Although none of the patients had pathological findings characteristic of CTE, 23 patients (38%) demonstrated tau-immunoreactive lesions, including neurites, neurofibrillary pretangles, neurofibrillary tangles, subpial tau, and/or glial tau. In 4 of the 23 patients (7% of the cohort; 17% of those with tau pathology), substantial tau burden was identified. Three of these 4 patients had no significant history of head trauma; 1 patient had multiple sports-related concussions. No specific clinical factors correlated with the presence of tau pathology. SIGNIFICANCE: Tau-immunoreactive lesions were found in 38% of 60 patients who underwent a focal cortical resection for drug-resistant focal epilepsy. Diagnostic features of CTE were not detected in any patient; however, the pathological evaluation for CTE was limited to a surgical specimen. The prominent and excessive tau deposition in 23 patients (38%) is abnormal in this age group and warrants further investigation.

The characteristics of all-terrain vehicle (ATV)-related deaths: A forensic autopsy data-based study.

Using forensic autopsy-based data from a regional medical examiner office in the midwestern U.S. with a mixed small urban-rural population, we describe the characteristics of all-terrain vehicle (ATV)-related deaths occurring between 2000 and 2018. During this period, there were 25 ATV-related deaths. There was a strong male predominance with 22 male and 3 female decedents. The average age at death was 35 years, with a range from 10 to 82 years, and a bimodal age distribution with one peak at 10-19 years old, and a second peak at 60-69 years old. The most common cause of death was blunt trauma (n = 22), with the remainder being torso compression (n = 1), drowning (n = 1) and hypothermia (n = 1). Of the 22 blunt trauma deaths, 15 were due to head trauma. The most common mechanism of accident was roll-over (n = 11), followed by striking a stationary object (n = 6). Of the stationary objects struck, the most common was cable wire fencing accounting for 3 of the 6. A survival period following discovery of the body was present in 11 of the 25 deaths. Postmortem toxicology was positive for ethanol in 7 deaths and tramadol in 1 death.

Transfusion-Related Acute Lung Injury After IVIG for Myasthenic Crisis.

BACKGROUND: A 26-year-old female with myasthenic crisis developed transfusion-related acute lung injury (TRALI) after she was treated with intravenous immunoglobulin. METHODS: Case report. RESULTS: Respiratory status markedly worsened with each intravenous immunoglobulin (IVIG) administration and progressing from a need to use bilevel positive airway pressure (BiPAP) to intubation. Pulmonary function tests improved during this episode. CONCLUSIONS: IVIG may cause TRALI and due to subtle clinical findings can be mistaken for neuromuscular respiratory failure.

Myoepithelial tumors of soft tissue and bone in children and young adults: A clinicopathologic study of 40 cases occurring in patients ≤ 21 Years of age.

Myoepithelial tumors of the soft tissue and bone occurring in patients 21 years of age and younger are rare, and their clinicopathologic features remain incompletely understood. We studied a well-characterized series of 40 such tumors. Cases were retrieved from our archives for the period 2009-2022 and re-reviewed. Available immunohistochemical and molecular genetic data was collected. Clinical information including available follow-up was obtained. The tumors occurred in 18 males and 22 females, ranging from 3 months to 21 years of age (median 11.5 years), and involved a wide variety of soft tissue (n = 36) and bone (n = 4) locations. Histologically benign myoepithelial tumors tended to occur in adolescents (median age 14.5 years; range 5-21 years), whereas myoepithelial carcinomas occurred in younger patients (median age 8.5 years; range 3 months-20 years). Microscopically, the tumors showed a complex admixture of epithelioid, plasmacytoid and spindled cells in a variably hyalinized, myxoid, chondroid or chondromyxoid background. Small subsets of histologically malignant tumors had rhabdoid or "round cell" features. Immunohistochemistry showed 35/40 (88%) cases to be positive with at least one keratin antibody. The 5 keratin-negative tumors were uniformly positive for S100 protein and/or SOX10 and expressed EMA (4 cases) and/or p63 (3 cases). EMA, SMA and GFAP were positive in 21/25 (84%), 13/21 (62%), and 8/21 (38%) tumors, respectively. SMARCB1 and SMARCA4 expression was retained in 29/31 (94%) and 22/22 (100%) of cases, respectively. FISH for EWSR1 gene rearrangement was positive in 6/18 (33%) tested cases. Two EWSR1-negative tumors were also FUS-negative. NGS identified EWSR1::POU5F1, FUS::KLF17, and BRD4::CITED1 gene fusions in 3 tested cases. Clinical follow-up (22 patients; median 23 months; range 1-119 months) showed 3 patients with local recurrences and 5 with distant metastases (lymph nodes, lung, and brain). Three patients died of disease, 3 were alive with recurrent or unresectable disease, and 16 were disease-free. Adverse clinical outcomes were seen only in patients with malignant tumors. We conclude that myoepithelial neoplasms of soft tissue and bone are over-repesented in patients ≤21 years of age, more often histologically malignant, and potentially lethal. Histologic evaluation appears to reliably predict the behavior of these rare tumors.

Primary spinal intramedullary anaplastic ganglioglioma in a pediatric patient.

Background: Gangliogliomas (GGs) are rare tumors of the central nervous system composed of neoplastic neural and glial cells and are typically low-grade. Intramedullary spinal anaplastic GGs (AGG) are rare, poorly understood, and often aggressive tumors that can result in widespread progression along the craniospinal axis. Due to the rarity of these tumors, data are lacking to guide clinical and pathologic diagnosis and standard of care treatment. Here, we present a case of pediatric spinal AGG to provide information on our institutional approach to work-up and to highlight unique molecular pathology. Case Description: A 13-year-old female presented with signs of spinal cord compression including right sided hyperreflexia, weakness, and enuresis. Magnetic resonance imaging (MRI) revealed a C3-C5 cystic and solid mass which was treated surgically with osteoplastic laminoplasty and tumor resection. Histopathologic diagnosis was consistent with AGG, and molecular testing identified mutations in H3F3A (K27M), TP53, and NF1. She received adjuvant radiation therapy and her neurological symptoms improved. However, at 6-month follow-up, she developed new symptoms. MRI revealed metastatic recurrence of tumor with leptomeningeal and intracranial spread. Conclusion: Primary spinal AGGs are rare tumors, but a growing body of literature shows some trends that may improve diagnosis and management. These tumors generally present in adolescence and early adulthood with motor/sensory impairment and other spinal cord symptoms. They are most commonly treated by surgical resection but frequently recur due to their aggressive nature. Further reports of these primary spinal AGGs along with characterization of their molecular profile will be important in developing more effective treatments.

Inflammatory Bowel Disease Presenting With Concurrent COVID-19 Multisystem Inflammatory Syndrome.

Coronavirus disease 2019 is associated with a postinfectious multisystem inflammatory syndrome in children (MIS-C). This syndrome is marked by cytokine storm and multiorgan dysfunction, often affecting the gastrointestinal tract, the heart, and the hematopoietic system. We describe the case of a 16-year-old boy with an initial presentation of severe inflammatory bowel disease and concurrent MIS-C. He presented with abdominal pain, diarrhea, and hematochezia and met criteria for the systemic inflammatory response syndrome. Laboratory inflammatory profiling revealed markedly elevated ferritin, D-dimer, C-reactive protein, soluble interleukin 2, and interleukin 6 levels. Endoscopy and colonoscopy revealed severe active gastroduodenitis, patchy colitis, and a normal-appearing terminal ileum. The patient was treated with a combination of steroids, intravenous immunoglobulin, and infliximab, and his symptoms slowly resolved over a 3-week period. In this case, we describe coincident MIS-C with a remarkably severe and difficult-to-treat initial presentation of inflammatory bowel disease and highlight the need to investigate the effect of coronavirus disease 2019 and MIS-C on inflammatory disorders.

Embryonal Tumors of the Central Nervous System: An Update.

Embryonal tumors of the central nervous system (CNS) are rare, high-grade neoplasms predominantly affecting the pediatric population. Well-defined embryonal tumors include medulloblastoma, atypical teratoid/rhabdoid tumor, embryonal tumor with multilayered rosettes, C19MC-altered and embryonal tumor with multilayered rosettes, not otherwise specified, pineoblastoma, pituitary blastoma, CNS neuroblastoma, and ganglioneuroblastoma. Although their prognosis is nearly uniformly poor, the rapidly evolving understanding of their molecular biology contributes to diagnosis, prognosis, treatment, and clinical trial participation. Knowledge of current tumor stratification and diagnostic techniques will help pathologists guide care and preserve tissue for necessary or desired additional testing.

Elevator-Related Deaths.

Elevators are mechanical transportation devices used to move vertically between different levels of a building. When first developed, elevators lacked the safety features. When safety mechanisms were developed, elevators became a common feature of multistory buildings. Despite their well-regarded safety record, elevators are not without the potential for danger of injury or death. Persons at-risk for elevator-related death include maintenance and construction workers, other employees, and those who are prone to risky behavior. Deaths may be related to asphyxia, blunt force, avulsion injuries, and various forms of environmental trauma. In this review, we report on 48 elevator-related deaths that occurred in nine different medicolegal death investigation jurisdictions within the United States over an approximately 30-year period. The data represents a cross-section of the different types of elevator-related deaths that may be encountered. The review also presents an overview of preventive strategies for the purpose of avoiding future elevator-related fatalities.

Association between contact sports participation and chronic traumatic encephalopathy: a retrospective cohort study.

Chronic traumatic encephalopathy is a debilitating neurodegenerative disorder associated with repetitive traumatic brain injuries often sustained through prior contact sport participation. The frequency of this disorder in a diverse population, including amateur athletes, is unknown. Primary historical obituary and yearbook records were queried for 2566 autopsy cases in the Mayo Clinic Tissue Registry resulting in identification of 300 former athletes and 450 non-athletes. In these cases, neocortical tissue was screened for tau pathology with immunohistochemistry, including pathology consistent with chronic traumatic encephalopathy, blinded to exposure or demographic information. Using research infrastructure of the Rochester Epidemiology Project, a comprehensive and established medical records-linkage system of care providers in southern Minnesota and western Wisconsin, medical diagnostic billing codes pertaining to head trauma, dementia, movement disorders, substance abuse disorders and psychiatric disorders were recorded for cases and controls in a blinded manner. A total of 42 individuals had pathology consistent with, or features of, chronic traumatic encephalopathy. It was more frequent in athletes compared to non-athletes (27 cases versus 15 cases) and was largely observed in men (except for one woman). For contact sports, American football had the highest frequency of chronic traumatic encephalopathy pathology (15% of cases) and an odds ratio of 2.62 (P-value = 0.005). Cases with chronic traumatic encephalopathy pathology had higher frequencies of antemortem clinical features of dementia, psychosis, movement disorders and alcohol abuse compared to cases without chronic traumatic encephalopathy pathology. Understanding the frequency of chronic traumatic encephalopathy pathology in a large autopsy cohort with diverse exposure backgrounds provides a baseline for future prospective studies assessing the epidemiology and public health impact of chronic traumatic encephalopathy and sports-related repetitive head trauma.

Facial nerve venous malformation: A radiologic and histopathologic review of 11 cases.

OBJECTIVE: The purpose of this article was to provide a combined pathologic and radiologic review of previous pathologically diagnosed facial nerve "hemangiomas" to confirm that these lesions are most characteristic of venous malformations rather than neoplasms. STUDY DESIGN: Retrospective radiologic, clinical, and histopathologic review of all patients with a previous pathologically diagnosed facial nerve hemangioma of the temporal bone who underwent computed tomography or magnetic resonance imaging (MRI) were included. A consensus radiologic review for characteristic features and pathologic analysis was performed. MATERIALS AND METHODS: A panel of 4 neuroradiologists retrospectively analyzed CT and MRI exams for 11 facial nerve hemangiomas and provided a consensus agreement on the characteristic imaging features. Concurrently, two neuropathologists reevaluated archived tissue specimens from these lesions and applied additional immunohistochemical and histochemical stains including D240, CD31, smooth muscle actin (SMA), Verhoeff Van Gieson (VVG) and glucose transporter 1 (GLUT1). RESULTS: Lesions were composed of dilated vascular spaces with a simple, CD31-positive endothelial lining and a smooth muscle component. All lesions were negative for markers found in arterial and lymphatic malformations and infantile hemangiomas. They had characteristic radiologic features previously ascribed to facial nerve hemangiomas. Namely, these lesions are typically T1 isointense or hypointense and T2 hyperintense relative to cerebral cortex and heterogeneously enhance on MRI. Bony canal expansion and erosion, intralesional calcification, and intracranial extension are common. CONCLUSIONS: On the basis of this radiologic and pathologic review, these lesions are best characterized as venous malformations. LEVEL OF EVIDENCE: 4.

Characteristics of Spontaneous Spinal Cord Infarction and Proposed Diagnostic Criteria.

Importance: Spinal cord infarction (SCI) is often disabling, and the diagnosis can be challenging without an inciting event (eg, aortic surgery). Patients with a spontaneous SCI are often misdiagnosed as having transverse myelitis. Diagnostic criteria for SCI are lacking, hindering clinical care and research. Objective: To describe the characteristics of spontaneous SCI and propose diagnostic criteria. Design, Setting, and Participants: An institution-based search tool was used to identify patients evaluated at Mayo Clinic, Rochester, Minnesota, from January 1997 to December 2017 with a spontaneous SCI. Patients provided written consent to use their records for research. Participants were 18 years and older with a diagnosis of spontaneous SCI (n = 133), and controls were selected from a database of alternative myelopathy etiologies for validation of the proposed diagnostic criteria (n = 280). Main Outcomes and Measures: A descriptive analysis of SCI was performed and used to propose diagnostic criteria, and the criteria were validated. Results: Of 133 included patients with a spontaneous SCI, the median (interquartile range) age at presentation was 60 (52-69) years, and 101 (76%) had vascular risk factors. Rapid onset of severe deficits reaching nadir within 12 hours was typical (102 [77%]); some had a stuttering decline (31 [23%]). Sensory loss occurred in 126 patients (95%), selectively affecting pain/temperature in 49 (39%). Initial magnetic resonance imaging (MRI) spine results were normal in 30 patients (24%). Characteristic MRI T2-hyperintense patterns included owl eyes (82 [65%]) and pencil-like hyperintensity (50 [40%]); gadolinium enhancement (37 of 96 [39%]) was often linear and located in the anterior gray matter. Confirmatory MRI findings included diffusion-weighted imaging/apparent diffusion coefficient restriction (19 of 29 [67%]), adjacent dissection/occlusion (16 of 82 [20%]), and vertebral body infarction (11 [9%]). Cerebrospinal fluid showed mild inflammation in 7 of 89 patients (8%). Diagnostic criteria was proposed for definite, probable, and possible SCI of periprocedural and spontaneous onset. In the validation cohort (n = 280), 9 patients (3%) met criteria for possible SCI, and none met criteria for probable SCI. Conclusions and Relevance: This large series of spontaneous SCIs provides clinical, laboratory, and MRI clues to SCI diagnosis. The diagnostic criteria proposed here will aid clinicians in making the correct diagnosis and ideally improve future care for patients with SCI. The validation of these criteria supports their utility in the evaluation of acute myelopathy.

Desmoplastic Infantile Ganglioglioma: A MAPK Pathway-Driven and Microglia/Macrophage-Rich Neuroepithelial Tumor.

MAPK pathway activation has been recurrently observed in desmoplastic infantile ganglioglioma/astrocytoma (DIG/DIA) with reported disproportionally low mutation allele frequencies relative to the apparent high tumor content, suggesting that MAPK pathway alterations may be subclonal. We sought to expand the number of molecularly profiled cases and investigate if tumor cell composition could account for the observed low mutation allele frequencies. Molecular (targeted neuro-oncology next-generation sequencing/RNA sequencing and OncoScan microarray) and immunohistochemical (CD68-PGM1/CD163/CD14/CD11c/lysozyme/CD3/CD20/CD34/PD-L1) studies were performed in 7 DIG. Activating MAPK pathway alterations were identified in 4 (57%) cases: 3 had a BRAF mutation (V600E/V600D/V600_W604delinsDQTDG, at 8%-27% variant allele frequency) and 1 showed a TPM3-NRTK1 fusion. Copy number changes were infrequent and nonrecurrent. All tumors had at least 30% of cells morphologically and immunophenotypically consistent with microglial/macrophage lineage. Two subtotally resected tumors regrew; 1 was re-excised and received adjuvant treatment (chemotherapy/targeted therapy), with clinical response to targeted therapy only. Even with residual tumor, all patients are alive (median follow-up, 83 months; 19-139). This study further supports DIG as another MAPK pathway-driven neuroepithelial tumor, thus expanding potential treatment options for tumors not amenable to surgical cure, and suggests that DIG is a microglia/macrophage-rich neuroepithelial tumor with frequent low driver mutation allele frequencies.

Identification of Bodies by Unique Serial Numbers on Implanted Medical Devices.

Visual identification is the most common identification method used by medical examiners but is not always possible. Alternative methods include X-ray, fingerprint, or DNA comparison, but these methods require additional resources. Comparison of serial numbers on implanted medical devices is a rapid and definitive method of identification. To assess the practicality of using this method, we reviewed 608 consecutive forensic autopsies performed at a regional medical examiner office. Of these, 56 cases required an alternative method of identification due to decomposition (n = 35), gunshot wound (n = 9), blunt trauma (n = 6), or charring (n = 6). Of these 56 cases, eight (14.3%) were known to have an implanted medical device. Of these eight cases, five (63%) could be positively identified by comparing serial numbers. If an implanted medical device is known to be present, and medical records are available, identification by medical device serial number should be a first-line method.