Digital Pathology in the Detection of Infectious Microorganisms: An Evaluation of Its Strengths and Weaknesses Across a Panel of Immunohistochemical and Histochemical Stains Routinely Used in Diagnostic Surgical Pathology.

CONTEXT.­: The diagnosis of some infectious diseases requires their identification in tissue specimens. As institutions adopt digital pathology for primary diagnosis, the limits of microorganism detection from digital images must be delineated. OBJECTIVE.­: To assess the reliability of microorganism detection from digitized images of histochemical and immunohistochemical stains commonly used in pathology. DESIGN.­: Original glass slides from 620 surgical pathology cases evaluated for the presence of infectious microorganisms were digitized. Immunohistochemical stains included those for herpes simplex virus (n = 100), cytomegalovirus (n = 100), Helicobacter pylori (n = 100), and spirochetes (n = 80). Histochemical stains included mucicarmine for Cryptococcus spp (n = 20), Grocott methenamine silver for fungi (n = 100), Giemsa for H pylori (n = 100), and Ziehl-Neelsen for acid-fast bacilli (n = 20). The original diagnosis based on the glass slides was regarded as the reference standard. Six pathologists reviewed the digital images. RESULTS.­: Digital review was generally associated with high (ie, ≥90%) specificity and positive predictive value owing to a low percentage of false positive reads, whereas a high percentage of false negatives contributed to low sensitivity and negative predictive value for many stains. Fleiss κ showed substantial interobserver agreement in the interpretation of Grocott methenamine silver and immunostains for herpes simplex virus, H pylori, and cytomegalovirus; moderate agreement for spirochete, Ziehl-Neelsen, and mucicarmine; and poor agreement for Giemsa. CONCLUSIONS.­: Digital immunohistochemistry generally outperforms histochemical stains for microorganism detection. Digital interpretation of Ziehl-Neelsen and mucicarmine stains is associated with low scores for interrater reliability, accuracy, sensitivity, and negative predictive value such that it should not substitute for conventional review of glass slides.

Discontinuation Syndrome With JAK2 Selective Agents: Case Presentation and Mechanistic Insights.

We report the first case of pacritinib-withdrawal syndrome with in vitro elucidation of underlying mechanisms.

Burkitt lymphoma of the nasopharynx causing life-threatening airway obstruction: A case report.

OBJECTIVE: To describe a case of Burkitt lymphoma (BL) in a child manifesting with acute airway obstruction. To review available literature on the clinical features and characteristic presentation of this disease. METHODS: Case report with literature review. RESULTS: We present the case of an 8-year-old boy with nasopharyngeal BL manifesting initially as sore throat, nasal congestion, and snoring that progressed to dyspnea and, ultimately, acute airway obstruction requiring emergent tracheostomy. The child was treated with intensive chemotherapy and achieved complete response. CONCLUSION: This case highlights the importance of maintaining high clinical suspicion when evaluating common otolaryngologic symptoms and emphasizes the potential for Burkitt lymphoma to cause rapid patient deterioration.

Biennial Upsurge and Molecular Epidemiology of Enterovirus D68 Infection in New York, USA, 2014 to 2018.

Enterovirus D68 (EV-D68) infection has been associated with outbreaks of severe respiratory illness and increased cases of nonpolio acute flaccid myelitis. The patterns of EV-D68 circulation and molecular epidemiology are not fully understood. In this study, nasopharyngeal (NP) specimens collected from patients in the Lower Hudson Valley, New York, from 2014 to 2018 were examined for rhinovirus/enterovirus (RhV/EV) by the FilmArray respiratory panel. Selected RhV/EV-positive NP specimens were analyzed using two EV-D68-specific real-time RT-PCR assays, Sanger sequencing and metatranscriptomic next-generation sequencing. A total of 2,398 NP specimens were examined. EV-D68 was detected in 348 patients with NP specimens collected in 2014 (n = 94), 2015 (n = 0), 2016 (n = 160), 2017 (n = 5), and 2018 (n = 89), demonstrating a biennial upsurge of EV-D68 infection in the study area. Ninety-one complete or nearly complete EV-D68 genome sequences were obtained. Genomic analysis of these EV-D68 strains revealed dynamics and evolution of circulating EV-D68 strains since 2014. The dominant EV-D68 strains causing the 2014 outbreak belonged to subclade B1, with a few belonging to subclade B2. New EV-D68 subclade B3 strains emerged in 2016 and continued in circulation in 2018. Clade D strains that are rarely detected in the United States also arose and spread in 2018. The establishment of distinct viral strains and their variable circulation patterns provide essential information for future surveillance, diagnosis, vaccine development, and prediction of EV-D68-associated disease prevalence and potential outbreaks.

Lymphoma Mimicking Chronic Active Epstein-Barr Virus: A Case Report.

Epstein-Barr virus (EBV) is the main cause of infectious mononucleosis (IM), a self-limiting infection among immunocompetent patients. EBV is also implicated in the development of several malignancies. We describe a case of a previously healthy 34-year-old man who presented with non-tender, enlarging, right cervical lymphadenopathy for over a year that was associated with significant weight loss, fevers, and night sweats. Two fine needle core biopsies showed inconclusive then reactive tissue, respectively. A third excisional biopsy demonstrated a reactive lymph node with EBV-positive IM. There was no evidence of lymphoma by histologic examination or flow cytometry. A diagnosis of chronic active EBV (CAEBV) was rendered. Subsequent lymph node debulking six months later showed classic Hodgkin lymphoma (CHL) positive for EBV. The patient underwent chemotherapy with full treatment response. This is an unusual presentation of EBV infection that led to either a delayed onset or delayed diagnosis of CHL.

Double or nothing: old chest X-ray as a clue to lung mass.

Mucoepidermoid carcinoma is ayoung person's lung cancer with no apparent causal connection to smoking. It exhibits slow growth, which can make it challenging to detect changes in size on serial chest imaging. Another way of describing its growth pattern is that mucoepidermoid carcinoma has an unusually long volume doubling time. We describe acase of an incidental lung nodule diagnosed as mucoepidermoid carcinoma in which aprior chest radiograph provided aclue to the indolent nature of the abnormality and therefore argued against typical lung cancer. In the same context, we underscore the value of volumetric analy-sis in improving the accuracy of nodule growth determinations, which further strengthens the argument that the importance of locating prior imaging has not diminished in contemporary pulmonary practice.

USP6 Gene Rearrangement by FISH Analysis in Cranial Fasciitis: A Report of Three Cases.

Cranial fasciitis (CF) is an uncommon benign myofibroblastic proliferation involving the soft and hard tissues of the cranium. It typically occurs in the pediatric population with a male predilection (male-to-female ratio 1.5:1). The clinical presentation is usually a rapidly expanding, painless nodule. Bone erosion may be appreciated radiographically. Histopathologic sections of CF show plump, fibroblast-like cells with pale, oval shaped nuclei and prominent nucleoli in a fibrous or myxoid background. Growth is self-limited and surgical excision is considered curative. Due to these features, CF is thought to be a variant of nodular fasciitis (NF). As with NF, CF may mimic a sarcomatous process and pose a diagnostic challenge to clinicians and pathologists alike. Erickson-Johnson et al. identified rearrangements of the ubiquitin-specific protease 6 (USP6) gene in 44 of 48 cases of NF. MYH9 was the fusion partner in 12 of these cases. To date, the molecular profile of CF has not been studied. Here we present the molecular findings in three cases of CF identified at our institution. Each case was subjected to fluorescence in-situ hybridization with appropriate negative controls. Two of three cases were positive for the USP6 gene rearrangement. The third case failed to hybridize, likely related to nucleic acid damage secondary to decalcification. Negative controls did not demonstrate the genetic rearrangement. These findings warrant further investigation of the USP6 gene rearrangement in CF, as it may prove helpful as a diagnostic adjunct in challenging cases.

The foramen of Monro: a review of its anatomy, history, pathology, and surgery.

INTRODUCTION: The foramen of Monro lies at the junction between the paired lateral ventricles and the third ventricle of the brain. METHODS: A comprehensive review of the literature was performed focusing on the foramen of Monro. CONCLUSIONS: A good understanding of the anatomy of the foramen of Monro is essential for the neurosurgeon, especially with the increasing use of intraventricular endoscopy.

Superior mesenteric artery syndrome and its associated gastrointestinal implications.

The superior mesenteric artery (SMA) syndrome is a rare but potentially life-threatening gastrointestinal condition. Over the years, it has been referenced by several names, the most common of which is Wilkie's syndrome. These numerous terminologies have made it difficult to estimate its true frequency in the general population. Common symptoms associated with this syndrome include intermittent postprandial abdominal pain, nausea, and bilious vomiting. Our review revealed that although it is currently well-defined in the literature, the diagnosis of SMA syndrome remains challenging as other disorders can mimic its presentation. However, CT angiography is currently favored in the literature for diagnosis as it can not only show the narrowed aorto-mesenteric angle and distance, but also the extent of duodenal obstruction. In addition, we found no consensus on the preferred mode of therapy once SMA syndrome is diagnosed. The agreement among authors is that the treatment options should be based on severity of the disease, using conservative measures as the first line of therapy in mild SMA syndrome. Duodenojejunostomy is the preferred surgical approach when conservative management fails, or in severe cases.