Pituicytomas and spindle cell oncocytomas: modern case series from the University of California, San Francisco.

PURPOSE: Pituicytomas and spindle cell oncocytomas (SCOs) are extremely rare neoplasms of the sellar and suprasellar region that can often mimic pituitary adenomas. To date, there are relatively few cases of pituicytomas and SCOs reported; and most of these are small case series. METHODS: In this paper, we provide a retrospective review of the treatment, imaging characteristics, post-operative course, and histopathology of five cases of pituicytomas and two SCOs treated at the University of California, San Francisco (UCSF) over a 10-year period from 2003 to 2013. RESULTS: We find that pituicytomas and SCOs present similarly to pituitary adenomas, and look identical on CT or MR imaging. We histopathologically confirmed all pituicytomas with a combination of hematoxylin and eosin morphology and immunohistochemical positivity for vimentin and S100; SCOs stain for anti-mitochondrial antigen and endothelial membrane antigen. We observe positive thyroid transcription factor 1 (TTF1) immunohistochemistry in both cases of SCO, as well as in both of the cases of pituicytoma in which TTF1 staining was available. CONCLUSIONS: This represents the largest single-institution case series of pituicytomas and SCOs to date, and also includes the first description of the management of a pregnant female with SCO. Our findings are consistent with the idea of common histogenesis for pituicytomas and SCOs, and also raise the possibility of more aggressive growth in SCOs as compared to pituicytomas.

Hypophysitis: a single-center case series.

PURPOSE: The authors review their treatment experience and summarize clinical outcomes for patients with hypophysitis over the past 15 years. METHODS: A retrospective analysis was conducted on patients with lymphocytic, granulomatous or IgG4-related hypophysitis treated from 1997 to 2014 at a single academic center. Patients' medical records were reviewed and binary logistic regression analysis was used to assess whether various clinical parameters were associated with improved outcomes including endocrine function, radiographic appearance and disease recurrence. RESULTS: Twenty-one patients (13 women and 8 men) were identified with a median diagnosis age of 37.4 years. All but two patients (90%) were diagnosed histopathologically and the remaining two were diagnosed clinically with lymphocytic hypophysitis. 16 patients (76%) had lymphocytic hypophysitis, 3 (14%) had granulomatous hypophysitis, 1 (5%) had IgG4-related hypophysitis and 1 (5%) had mixed lymphocytic-granulomatous. Patients presented with various symptoms of expanding sellar mass with most common signs including headache (57%), polyuria/polydipsia (52%), vision changes (52%) and amenorrhea or decreased libido (48%). Pre-treatment endocrine evaluation revealed that 12 (57%) patients had complete anterior hypopituitarism, 11 patients (52%) had diabetes insipidus, ten patients (48%) had mild hyperprolactinemia and three patients (14%) had isolated endocrine axis deficiencies with partial gland function. We observed a broad diversity in pre-treatment imaging with common findings including uniform contrast enhancement (62%), thickened infundibulum (57%) and loss of hypophysis bright spot on T1 imaging (43%). Patients were treated with steroids and hormone supplementation as needed. 16 patients (76%) had recorded post-treatment MRI scans which revealed that half had radiographic improvement and half had stable or worsened post-treatment imaging. Only female gender was found to significantly predict improved odds of post-steroid radiographic improvement. For post-treatment endocrine evaluation, six patients (29%) did not have an evaluation on record, four patients (19%) had some improvement in at least one axis, seven patients (33%) had stable but non-worsened endocrine function and four patients (19%) had worsened endocrine function post-steroids. CONCLUSIONS: Hypophysitis is an increasingly recognized diagnosis that can present with a broad array of radiographic and clinical features. Surgical biopsy can be helpful to make definitive diagnosis and may guide treatment decision-making.

Dysphagia and Muscle Weakness Secondary to Botulinum Toxin Type A Treatment of Cervical Dystonia: A Drug Class Analysis of Prescribing Information.

The first-line management of cervical dystonia (CD) symptoms is intramuscular injection of botulinum toxin type A (BoNTA). However, a comparison of safety among BoNTAs is difficult because, per regulatory authorities, units of BoNTA activity are not interchangeable. Dysphagia and muscle weakness are widely considered two key adverse events to monitor closely in the treatment of CD. This integrated analysis compared the safety of BoNTAs approved for CD in the US by evaluating relationships between the incidence of dysphagia and muscle weakness in prescribing information and the core neurotoxin content. Coefficients The coefficients of determination (R2) and trendlines were estimated via regression-based lines of best fit. Adverse drug reaction (ADR) rates were strongly correlated with core neurotoxin amounts for conventional BoNTAs (slope coefficients: dysphagia = 0.048, R2 = 0.74; muscle weakness = 0.096, R2 = 0.82). The published ADR rates at approved doses for conventional BoNTAs were higher compared with DaxibotulinumtoxinA (DAXI; DAXXIFY®, Revance Therapeutics, Inc., Nashville, TN, USA) by core neurotoxin content. The use of a core neurotoxin amount was found to be an effective method for comparing the safety of BoNTA products. Current clinical trials suggest that DAXI, a novel BoNTA formulation, provides a potentially wider safety margin compared with other approved BoNTAs for CD. The lower amount of core neurotoxin administered at approved doses compared with conventional BoNTAs may explain low on-target ADRs like muscle weakness, whereas reduced diffusion from the injection site is thought to be responsible for low off-target ADRs like dysphagia.

Cortical ependymoma with unusual histologic features.

Cortical ependymomas are rare gliomas with classic ependymal features but are unusual in primarily involving the cerebral cortex. Here, we present a 19-year old woman with new-onset seizures who was found to have a large, cortically based non-enhancing lesion with scalloping of the overlying calvarium. Abundant ependymal features were present including classic ependymal cytology, diffuse GFAP and dot-like EMA positivity, and well developed cilia, microvilli, and intercellular junctions on ultrastructural analysis. Additionally, the tumor showed areas of infiltrative growth similar to angiocentric glioma as well as striking mucin-filled microcystic spaces somewhat reminiscent of myxopapillary ependymoma. Thus far, the patient shows no evidence of recurrence following gross total resection. This case demonstrates detailed morphologic, immunohistochemical, and ultrastructural evidence supporting a relationship between cortical ependymoma and angiocentric glioma and suggesting that cortical ependymomas can have myxopapillary as well as classic features.

TLQP-21 is a low potency partial C3aR activator on human primary macrophages.

TLQP-21 is a 21-amino acid neuropeptide derived from the VGF precursor protein. TLQP-21 is expressed in the nervous system and neuroendocrine glands, and demonstrates pleiotropic roles including regulating metabolism, nociception and microglial functions. Several possible receptors for TLQP-21 have been identified, with complement C3a receptor (C3aR) being the most commonly reported. However, few studies have characterised the activity of TLQP-21 in immune cells, which represent the major cell type expressing C3aR. In this study, we therefore aimed to define the activity of both human and mouse TLQP-21 on cell signalling in primary human and mouse macrophages. We first confirmed that TLQP-21 induced ERK signalling in CHO cells overexpressing human C3aR, and did not activate human C5aR1 or C5aR2. TLQP-21 mediated ERK signalling was also observed in primary human macrophages. However, the potency for human TLQP-21 was 135,000-fold lower relative to C3a, and only reached 45% at the highest dose tested (10 µM). Unlike in humans, mouse TLQP-21 potently triggered ERK signalling in murine macrophages, reaching near full activation, but at ~10-fold reduced potency compared to C3a. We further confirmed the C3aR dependency of the TLQP-21 activities. Our results reveal significant discrepancy in TLQP-21 C3aR activity between human and murine receptors, with mouse TLQP-21 being consistently more potent than the human counterpart in both systems. Considering the supraphysiological concentrations of hTLQP-21 needed to only partially activate macrophages, it is likely that the actions of TLQP-21, at least in these immune cells, may not be mediated by C3aR in humans.

Acute Appendicitis with Neuronal Hyperplasia and Swelling: A Novel Histologic Mimic of Appendiceal Goblet Cell Adenocarcinoma and Signet-Ring Cell Adenocarcinoma.

Goblet cell adenocarcinoma and signet-ring cell adenocarcinoma are well-known diagnostic pitfalls of routine appendectomy specimens. Here we present a case of acute appendicitis with prominent neuronal (ganglion cell) hyperplasia and swelling which histologically mimics goblet cell adenocarcinoma and signet-ring cell adenocarcinoma. Attention to the cytologic features of the lesional cells (absence of atypia, mitotic activity) and their close association with nerves and classic ganglion cells, along with the use of a limited panel of immunostains, ensures proper classification of this rare but striking benign process.

First in patient assessment of brain tumor infiltrative margins using simultaneous time-resolved measurements of 5-ALA-induced PpIX fluorescence and tissue autofluorescence.

SIGNIFICANCE: 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence is currently used for image-guided glioma resection. Typically, this widefield imaging method highlights the bulk of high-grade gliomas, but it underperforms at the infiltrating edge where PpIX fluorescence is not visible to the eyes. Fluorescence lifetime imaging (FLIm) has the potential to detect PpIX fluorescence below the visible detection threshold. Moreover, simultaneous acquisition of time-resolved nicotinamide adenine (phosphate) dinucleotide [NAD(P)H] fluorescence may provide metabolic information from the tumor environment to further improve overall tumor detection. AIM: We investigate the ability of pulse sampling, fiber-based FLIm to simultaneously image PpIX and NAD(P)H fluorescence of glioma infiltrative margins in patients. APPROACH: A mesoscopic fiber-based point-scanning FLIm device (355 nm pulses) was used to simultaneously resolve the fluorescence decay of PpIX (629/53 nm) and NAD(P)H (470/28 nm). The FLIm device enabled data acquisition at room light and rapid (<33 ms) augmentation of FLIm parameters on the surgical field-of-view. FLIm measurements from superficial tumors and tissue areas around the resection margins were performed on three glioblastoma patients in vivo following inspection of PpIX visible fluorescence with a conventional neurosurgical microscope. Microbiopsies were collected from FLIm imaged areas for histopathological evaluation. RESULTS: The average lifetime from PpIX and NAD(P)H fluorescence distinguished between tumor and surrounding tissue. FLIm measurements of resection margins presented a range of PpIX and NAD(P)H lifetime values (τPpIX   ∼ 3 to 14 ns, τNAD(P)H = 3 to 6 ns) associated with unaffected tissue and areas of low-density tumor infiltration. CONCLUSIONS: Intraoperative FLIm could simultaneously detect the emission of PpIX and NAD(P)H from patients in vivo during craniotomy procedures. This approach doubles as a clinical tool to identify tumor areas while performing tissue resection and as a research tool to study tumor microenvironmental changes in vivo. Intraoperative FLIm of 5-ALA-induced PpIX and tissue autofluorescence makes a promising surgical adjunct to guide tumor resection surgery.

Skeletal muscle pathology in Costello and cardio-facio-cutaneous syndromes: developmental consequences of germline Ras/MAPK activation on myogenesis.

Cardio-facio-cutaneous syndrome (CFC) and Costello syndrome (CS) are two of the more rare RASopathies caused by altered signal transduction of the Ras/mitogen-activated protein kinase (MAPK) pathway. All of the RASopathies exhibit some degree of hypotonia, but CS and CFC are more severe. To determine if individuals with CS and CFC have an underlying skeletal myopathy, we systematically evaluated skeletal muscle pathology in both conditions. We reviewed pathology reports from six individuals who had undergone a skeletal muscle biopsy, and we reviewed histology slides on two cases with CS and one case with CFC. All patients in the cohort had histopathologic findings, and two consistent abnormalities were identified. The first was the presence of abnormal muscle fiber size and variability, and the second was the presence of type 2 fiber predominance. Given the degree of hypotonia typically present in these patients, the overall architecture of the muscle was relatively normal, without showing indications of severe structural histopathology or metabolic abnormalities. Because the Ras/MAPK pathway is vital for skeletal myogenesis, we evaluated the effects of CS and CFC mutations on myogenesis using C2C12 myoblasts. All CS/CFC mutations inhibited myoblast differentiation as indicated by fewer myosin heavy chain expressing cells and a decrease in the number of myotubes as compared to controls. These findings indicate that CS and CFC may have a true myopathy related to an inherent dysregulation of skeletal myogenesis, which further expands our understanding of the consequences of germline Ras/MAPK mutations.

Comprehensive analysis of diverse low-grade neuroepithelial tumors with FGFR1 alterations reveals a distinct molecular signature of rosette-forming glioneuronal tumor.

The FGFR1 gene encoding fibroblast growth factor receptor 1 has emerged as a frequently altered oncogene in the pathogenesis of multiple low-grade neuroepithelial tumor (LGNET) subtypes including pilocytic astrocytoma, dysembryoplastic neuroepithelial tumor (DNT), rosette-forming glioneuronal tumor (RGNT), and extraventricular neurocytoma (EVN). These activating FGFR1 alterations in LGNET can include tandem duplication of the exons encoding the intracellular tyrosine kinase domain, in-frame gene fusions most often with TACC1 as the partner, or hotspot missense mutations within the tyrosine kinase domain (either at p.N546 or p.K656). However, the specificity of these different FGFR1 events for the various LGNET subtypes and accompanying genetic alterations are not well defined. Here we performed comprehensive genomic and epigenomic characterization on a diverse cohort of 30 LGNET with FGFR1 alterations. We identified that RGNT harbors a distinct epigenetic signature compared to other LGNET with FGFR1 alterations, and is uniquely characterized by FGFR1 kinase domain hotspot missense mutations in combination with either PIK3CA or PIK3R1 mutation, often with accompanying NF1 or PTPN11 mutation. In contrast, EVN harbors its own distinct epigenetic signature and is characterized by FGFR1-TACC1 fusion as the solitary pathogenic alteration. Additionally, DNT and pilocytic astrocytoma are characterized by either kinase domain tandem duplication or hotspot missense mutations, occasionally with accompanying NF1 or PTPN11 mutation, but lacking the accompanying PIK3CA or PIK3R1 mutation that characterizes RGNT. The glial component of LGNET with FGFR1 alterations typically has a predominantly oligodendroglial morphology, and many of the pilocytic astrocytomas with FGFR1 alterations lack the biphasic pattern, piloid processes, and Rosenthal fibers that characterize pilocytic astrocytomas with BRAF mutation or fusion. Together, this analysis improves the classification and histopathologic stratification of LGNET with FGFR1 alterations.

The genetic landscape of anaplastic pleomorphic xanthoastrocytoma.

Pleomorphic xanthoastrocytoma (PXA) is an astrocytic neoplasm that is typically well circumscribed and can have a relatively favorable prognosis. Tumor progression to anaplastic PXA (WHO grade III), however, is associated with a more aggressive biologic behavior and worse prognosis. The factors that drive anaplastic progression are largely unknown. We performed comprehensive genomic profiling on a set of 23 PXAs from 19 patients, including 15 with anaplastic PXA. Four patients had tumor tissue from multiple recurrences, including two with anaplastic progression. We find that PXAs are genetically defined by the combination of CDKN2A biallelic inactivation and RAF alterations that were present in all 19 cases, most commonly as CDKN2A homozygous deletion and BRAF p.V600E mutation but also occasionally BRAF or RAF1 fusions or other rearrangements. The third most commonly altered gene in anaplastic PXA was TERT, with 47% (7/15) harboring TERT alterations, either gene amplification (n = 2) or promoter hotspot mutation (n = 5). In tumor pairs analyzed before and after anaplastic progression, two had increased copy number alterations and one had TERT promoter mutation at recurrence. Less commonly altered genes included TP53, BCOR, BCORL1, ARID1A, ATRX, PTEN, and BCL6. All PXA in this cohort were IDH and histone H3 wildtype, and did not contain alterations in EGFR. Genetic profiling performed on six regions from the same tumor identified intratumoral genomic heterogeneity, likely reflecting clonal evolution during tumor progression. Overall, anaplastic PXA is characterized by the combination of CDKN2A biallelic inactivation and oncogenic RAF kinase signaling as well as a relatively small number of additional genetic alterations, with the most common being TERT amplification or promoter mutation. These data define a distinct molecular profile for PXA and suggest additional genetic alterations, including TERT, may be associated with anaplastic progression.

Mating activates NMDA receptors in the medial preoptic area of male rats.

Studies have emphasized the role of the medial preoptic area (MPOA) as an important site for the regulation of male sexual behavior. Indeed, ablations of the MPOA impair sexual behavior, whereas stimulation of the MPOA enhances behavior. Furthermore, neural activity in the MPOA increases with mating. The current study tested the hypothesis that activation of N-methyl-D-aspartate (NMDA) receptors occurs in MPOA neurons and is essential for the expression of male sexual behavior in rats. Results indicate that nearly all MPOA neurons that expressed Fos following mating also contained the NR1 subunit of NMDA receptors. Furthermore, mating increased phosphorylation, thus activation, of NR1 in the MPOA. Additionally, blocking NMDA receptors significantly decreased mating-induced Fos expression and mating-induced phosphorylation of NMDA receptors and impaired male sexual behavior. These results provide evidence that mating activates NMDA receptors in the MPOA and that this activation is important for the expression of male sexual behavior.

The suprachiasmatic nucleus: a clock of multiple components.

Although impressive progress has been made in understanding the molecular basis of pacemaker function in the suprachiasmatic nucleus (SCN), fundamental questions about cellular and regional heterogeneity within the SCN, and how this heterogeneity might contribute to SCN pacemaker function at a tissue level, have remained unresolved. To reexamine cellular and regional heterogeneity within the SCN, the authors have focused on two key questions: which SCN cells are endogenously rhythmic and/or directly light responsive? Observations of endogenous rhythms of electrical activity, gene/protein expression, and protein phosphorylation suggest that the SCN in mammals examined to date is composed of anatomically distinct rhythmic and nonrhythmic components. Endogenously rhythmic neurons are primarily found in rostral, dorsomedial, and ventromedial portions of the nucleus; at mid and caudal levels, the distribution of endogenously rhythmic cells in the SCN has the appearance of a "shell." The majority of nonrhythmic cells, by contrast, are located in a central "core" region of the SCN, which is complementary to the shell. The location of light-responsive cells, defined by direct retinohypothalamic input and light-induced gene expression, largely overlaps the location of nonrhythmic cells in the SCN core, although, in hamsters and mice light-responsive cells are also present in the ventral portion of the rhythmic shell. While the relative positions of rhythmic and light-responsive components of the SCN are similar between species, the precise boundaries of these components, and neurochemical phenotype of cells within them, are variable. Intercellular communication between these components may be a key feature responsible for the unique pacemaker properties of the SCN observed at a tissue and whole animal level.

The basics of intraoperative diagnosis in neuropathology.

Intraoperative pathologic consultation continues to be an essential tool during neurosurgical procedures, helping to ensure adequacy of material for achieving a pathologic diagnosis and to guide surgeons. For pathologists, successful consultation with central nervous system lesions involves not only a basic familiarity with the pathologic features of such lesions but also an understanding of their clinical and radiologic context. This review discusses a basic approach to intraoperative diagnosis for practicing pathologists, including preparation for, performance of, and interpretation of an intraoperative neuropathologic evaluation. The cytologic and frozen section features of select examples of common pathologic entities are described.

Pharyngeal Electrical Stimulation for Treatment of Poststroke Dysphagia: Individual Patient Data Meta-Analysis of Randomised Controlled Trials.

Background. Dysphagia after stroke is common, associated independently with poor outcome, and has limited treatment options. Pharyngeal electrical stimulation (PES) is a novel treatment being evaluated for treatment of poststroke dysphagia. Methods. We searched electronically for randomised controlled trials of PES in dysphagic patients within 3 months of stroke. Individual patient data were analysed using regression, adjusted for trial, age, severity, and baseline score. The coprimary outcomes were radiological aspiration (penetration aspiration score, PAS) and clinical dysphagia (dysphagia severity rating scale, DSRS) at 2 weeks; secondary outcomes included functional outcome, death, and length of stay in hospital. Results. Three completed trials were identified: 73 patients, age 72 (12) years, severity (NIHSS) 11 (6), DSRS 6.7 (4.3), mean PAS 4.3 (1.8). Compared with no/sham stimulation, PES was associated with lower PAS, 3.4 (1.7) versus 4.1 (1.7), mean difference -0.9 (p = 0.020), and lower DSRS, 3.5 (3.8) versus 4.9 (4.4), mean difference -1.7 (p = 0.040). Length of stay in hospital tended to be shorter: 50.2 (25.3) versus 71.2 (60.4) days (p = 0.11). Functional outcome and death did not differ between treatment groups. Conclusions. PES was associated with less radiological aspiration and clinical dysphagia and possibly reduced length of stay in hospital across three small trials.

Reliability and validity testing of automated scoring in obstructive sleep apnea diagnosis with the Embletta X100.

OBJECTIVES/HYPOTHESIS: To verify the reliability and validity of automated scoring and compare it to that of manual scoring for diagnosing obstructive sleep apnea using an Embletta X100 level 2 portable device. STUDY DESIGN: Retrospective study. METHODS: A total of 116 patients with suspected obstructive sleep apnea who had successfully received portable polysomnography with the Embletta X100 were examined. All polysomnography data were analyzed by automated and manual methods. Manual scoring was performed according to the revised American Academy of Sleep Medicine 2012 criteria. Automated scoring was analyzed using the automatic algorithm, which was updated with the American Academy of Sleep Medicine 2012 criteria. All parameters were evaluated statistically using correlation analysis and paired t tests. RESULTS: The apnea-hypopnea index for automated scoring and manual scoring with the Embletta X100 were moderately correlated (r = 0.76, P < .001). However, there was poor agreement (Bland-Altman plot, κ = 0.34, 0.33, and 0.26; cutoff value = 5, 15, and 30), and the apnea-hypopnea index data were generally excessively underestimated based on diagnostic agreement and disagreement criteria. Furthermore, the apnea-hypopnea index severity (Kendall tau-b = 0.62) between automated and manual scoring lacked good concordance. CONCLUSIONS: Automated scoring using the Embletta X100 was statistically moderately related to the manual scoring results. However, automated scoring tended to excessively underestimate the apnea-hypopnea index data compared to manual scoring. Thus, manual scoring by a sleep expert is essential for obstructive sleep apnea diagnosis with the Embletta X100. LEVEL OF EVIDENCE: 4.

Comparative utility of LC3, p62 and TDP-43 immunohistochemistry in differentiation of inclusion body myositis from polymyositis and related inflammatory myopathies.

BACKGROUND: Inclusion body myositis (IBM) is a slowly progressive inflammatory myopathy of the elderly that does not show significant clinical improvement in response to steroid therapy. Distinguishing IBM from polymyositis (PM) is clinically important since PM is steroid-responsive; however, the two conditions can show substantial histologic overlap. RESULTS: We performed quantitative immunohistochemistry for (1) autophagic markers LC3 and p62 and (2) protein aggregation marker TDP-43 in 53 subjects with pathologically diagnosed PM, IBM, and two intermediate T cell-mediated inflammatory myopathies (polymyositis with COX-negative fibers and possible IBM). The percentage of stained fibers was significantly higher in IBM than PM for all three immunostains, but the markers varied in sensitivity and specificity. In particular, both LC3 and p62 were sensitive markers of IBM, but the tradeoff between sensitivity and specificity was smaller (and diagnostic utility thus greater) for LC3 than for p62. In contrast, TDP-43 immunopositivity was highly specific for IBM, but the sensitivity of this test was low, with definitive staining present in just 67% of IBM cases. CONCLUSIONS: To differentiate IBM from PM, we thus recommend using a panel of LC3 and TDP-43 antibodies: the finding of <14% LC3-positive fibers helps exclude IBM, while >7% of TDP-43-positive fibers strongly supports a diagnosis of IBM. These data provide support for the hypothesis that disruption of autophagy and protein aggregation contribute to IBM pathogenesis.

LC3 and p62 as diagnostic markers of drug-induced autophagic vacuolar cardiomyopathy: a study of 3 cases.

Autophagic vacuolar cardiomyopathy is an underrecognized, but potentially fatal, complication of treatment with chloroquine (CQ) and its derivative hydroxychloroquine (HCQ), which are used as therapy for malaria and common connective tissue disorders. Currently, the diagnosis of autophagic vacuolar cardiomyopathy is established through an endomyocardial biopsy and requires electron microscopy, which is not widely available and has a significant potential for sampling error. Recently, we have reported that immunohistochemistry for autophagic markers LC3 and p62 can replace electron microscopy in the diagnosis of HCQ-induced and colchicine-induced autophagic vacuolar skeletal myopathies. In the current study, we use 3 cases of CQ-induced or HCQ-induced cardiomyopathy and 1 HCQ-treated control case to show that the same two markers can be used to diagnose autophagic vacuolar cardiomyopathies by light microscopy. CQ-induced or HCQ-induced autophagic vacuolar cardiomyopathy is not universally fatal, but successful treatment requires early detection. By lowering the barriers to diagnosis, the application of these immunohistochemical markers will decrease the number of misdiagnosed patients, thus increasing the likelihood of favorable clinical outcomes.

Clinical utility of LC3 and p62 immunohistochemistry in diagnosis of drug-induced autophagic vacuolar myopathies: a case-control study.

BACKGROUND: Some patients treated with chloroquine, hydroxychloroquine, or colchicine develop autophagic vacuolar myopathy, the diagnosis of which currently requires electron microscopy. The goal of the current study was to develop an immunohistochemical diagnostic marker for this pathologic entity. METHODOLOGY: Microtubule-associated protein light chain 3 (LC3) has emerged as a robust marker of autophagosomes. LC3 binds p62/SQSTM1, an adapter protein that is selectively degraded via autophagy. In this study, we evaluated the utility of immunohistochemical stains for LC3 and p62 as diagnostic markers of drug-induced autophagic vacuolar myopathy. The staining was performed on archival muscle biopsy material, with subject assignment to normal control, drug-treated control, and autophagic myopathy groups based on history of drug use and morphologic criteria. PRINCIPAL FINDINGS: In all drug-treated subjects, but not in normal controls, LC3 and p62 showed punctate staining characteristic of autophagosome buildup. In the autophagic myopathy subjects, puncta were coarser and tended to coalesce into linear structures aligned with the longitudinal axis of the fiber, often in the vicinity of vacuoles. The percentage of LC3- and p62-positive fibers was significantly higher in the autophagic myopathy group compared to either the normal control (p<0.001) or the drug-treated control group (p<0.05). With the diagnostic threshold set between 8% and 15% positive fibers (depending on the desired level of sensitivity and specificity), immunohistochemical staining for either LC3 or p62 could be used to identify subjects with autophagic vacuolar myopathy within the drug-treated subject group (p ≤ 0.001). SIGNIFICANCE: Immunohistochemistry for LC3 and p62 can facilitate tissue-based diagnosis of drug-induced autophagic vacuolar myopathies. By limiting the need for electron microscopy (a time consuming and costly technique with high specificity, but low sensitivity), clinical use of these markers will improve the speed and accuracy of diagnosis, resulting in significantly improved clinical care.

Cerebral vasculopathy after 4-bromo-2,5-dimethoxyphenethylamine ingestion.

BACKGROUND: 4-bromo-2,5-dimethoxyphenethylamine (2C-B) is a designer-drug variant of 3,4-methylenedioxymethamphetamine (ecstasy) whose recreational use has increased significantly over the last 10 years. Neurologic consequences of 2C-B usage are currently unknown. CASE REPORT: A 43-year-old woman experienced severe headaches within 48 hours of taking liquid 2C-B, after which time she developed progressive encephalopathy and quadraparesis, which did not improve over several months. MRA and cerebral angiogram imaging demonstrated profound vascular abnormalities of large, medium, and small-caliber vessels with subsequent watershed infarction. Brain biopsy and cerebrospinal fluid studies ruled out an inflammatory process. CONCLUSIONS: This case demonstrates an idiosyncratic and devastating neurologic response to 2C-B, a recreational drug whose popularity has increased with widespread availability of online guides for its synthesis.