bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hemangioma Versus Vascular Malformation: Presence of Nerve Bundle Is a Diagnostic Clue for Vascular Malformation
Authors: Adegboyega Patrick A. , Qiu Suimin 
Published: February 2021

Abstract
Context.—Arteriovenous vascular malformations and hemangiomas are benign vascular lesions that are difficult to distinguish from one another clinically. Also, they may be confused with each other at histopathology. Therefore, histochemical stains for the presence of an artery are frequently used to distinguish between the two.
Objective.—Because it is clinically relevant to differentiate between arteriovenous vascular malformations and hemangiomas, this study was carried out to explore additional diagnostic clues that may help in the diagnosis and differentiation of these lesions.
Design.—A total of 167 cases of benign extracranial vascular lesions were retrieved from the anatomic pathology file of our institution. These comprised 66 cases diagnosed as arteriovenous vascular malformations and 101 cases previously diagnosed as hemangiomas. The hematoxylin-eosin–stained glass slides were reviewed, Movat pentichrome histochemical stain was used to identify elastic vessels (arteries/arterioles), and S100 immunostain was used to identify nerves within these vascular lesions. For immunohistochemistry, the avidin-biotin detection method was used.
Results.—With Movat stain, the presence of thick-walled elastic arteries was detected in 12 of the 101 cases previously diagnosed as hemangiomas, and these cases were therefore reclassified as vascular malformations. Using the same criterion, 2 of the 66 cases originally diagnosed as arteriovenous vascular malformations were reclassified as hemangiomas because they lacked arterial structures. Thus, with this strict criterion, we ended up with 91 cases of hemangiomas and 76 cases of arteriovenous vascular malformations. Intralesional nerves were identified in 91% (69/76) of cases of arteriovenous vascular malformations, including all the 12 arteriovenous vascular malformations previously diagnosed as hemangiomas. In contrast, no intralesional nerve was detected in any of the 91 hemangiomas.
Conclusions.—These results show that nerve bundles are consistently present in vascular malformations and absent in hemangiomas and so can be used as a diagnostic clue to differentiate between these lesions. Also, in addition to describing a previously unreported component of vascular malformations, these data further confirm the hamartomatous nature of these lesions.
Validation of a Rapid Diagnostic Strategy for Determination of Significant Bacterial Counts in Bronchoalveolar Lavage Samples
Authors: Laupland Kevin B. , Church Deirdre L. , Gregson Daniel B. 
Published: February 2021

Abstract
Context.—Bacterial cultures of bronchoscopic samples require 1 to 2 days for results to be available for use in clinical decisions. We developed a rapid diagnostic testing strategy that is highly sensitive for screening bacteria in bronchoalveolar lavage (BAL) samples, with results available within hours of collection.
Objective.—To validate the ability of a bacterial adenosine triphosphate (ATP) assay and routine Gram stain microscopy to detect significant bacterial counts in BAL samples.
Design.—Four hundred seventy-seven BAL samples from 319 patients suspected of having pneumonia were tested using a rapid diagnostic strategy, consisting of Gram stain and a bacterial ATP assay. Rapid results were compared with quantitative cultures with a positive cutoff of 104 CFU/mL or higher.
Results.—Significant bacterial counts were identified in 107 samples (22%). The most common etiologic agents were Staphylococcus aureus (25%), Haemophilus influenzae (17%), and Streptococcus pneumoniae (12%). The rapid test results were false negative in 5 cases (S aureus in 2, both Klebsiella pneumoniae and S aureus in 1, and Stenotrophomonas maltophilia and S pneumoniae in 1 case each). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the rapid diagnostic strategy were 95.3%, 54.9%, 37.9%, 97.6%, and 63.9%, respectively.
Conclusion.—A negative result with this rapid diagnostic testing strategy rules out significant bacterial counts in BAL samples with a high degree of certainty and may allow use of narrow-spectrum antimicrobial agents or withholding of empiric antimicrobial therapy in patients suspected of having ventilator-associated pneumonia.
Incidental Stromal-Predominant Mixed Epithelial-Stromal Tumors of the Kidney: A Mimic of Intraparenchymal Renal Leiomyoma
Authors: Parikh Parin , Chan Theresa Y. , Epstein Jonathan I. , Argani Pedram 
Published: February 2021

Abstract
Context.—Mixed epithelial-stromal tumor of the kidney is a recently recognized benign renal tumor that usually occurs in adult women and typically forms a sizable lesion with solid and cystic areas. The recognized morphologic spectrum of this recently described entity is evolving.
Objective.—To review the clinicopathologic features of 3 small mixed epithelial-stromal tumors of the kidney that were incidental findings in kidneys removed for other reasons.
Design.—The clinical presentation and morphologic findings of the 3 cases were reviewed. A panel of immunohistochemical stains was performed.
Setting.—Academic medical center.
Results.—All 3 lesions contained predominantly fascicles of smooth muscle mimicking leiomyoma, but they also had cellular subpopulations of smaller, müllerian-appearing stromal cells. Tubules present within the lesion were most abundant at the periphery, suggesting that they might be entrapped. Although only the spindled smooth muscle cells were immunoreactive for muscle markers desmin and actin, both the spindled smooth muscle cells and the cellular müllerian-appearing stromal cells demonstrated diffuse nuclear labeling for estrogen and progesterone receptors.
Conclusions.—Mixed epithelial-stromal tumor of the kidney may present as an incidental stromal-predominant lesion within the kidney. Such lesions are easily confused with leiomyomas or stromal-predominant angiomyolipomas.
Whipple Disease: A Case Report and Review of the Literature
Authors: Muir-Padilla M. A. J. Jeannie , Myers C. O. L. Jerome B. 
Published: February 2021

Abstract
Whipple disease is a chronic, relapsing, and multisystem disease. It presents a diagnostic challenge for both clinicians and pathologists. Recent advances in isolation and culture have identified the organism responsible for the disease to be a member of the order Actinomycetes designated Tropheryma whipplei. Several immune system changes have been noted in patients with Whipple disease, but whether these are primary or secondary is as yet undetermined. Long-term antibiotic therapy is required, and relapses are common, especially with central nervous system involvement.
Increased Blasts Mimicking Acute Leukemia in a Patient With Polysubstance Abuse
Authors: Bianco Michelle , Turner John , Rosenthal Nancy 
Published: February 2021

Abstract
Toxic insult to the bone marrow may result in partial or complete suppression, with or without reactive changes, and probable eventual regeneration of hematopoietic elements. During the regenerative process, increased blasts may be observed. Distinguishing these changes from an acute leukemic process can be difficult. In particular, the diagnosis of hypocellular bone marrow with increased blasts, also known as hypocellular or hypoplastic acute leukemia, presents a diagnostic dilemma for pathologists. We report a case of hypocellular marrow with increased blasts in a 50-year-old man with an extensive history of alcohol and drug abuse in whom chemotherapy was deferred. Recovery of peripheral blood cell counts and reticulocytosis occurred with withdrawal of the offending agents, and he remains alive and well 1 year later.
Nectin-1 Expression in the Normal and Neoplastic Human Uterine Cervix
Authors: Guzman Grace , Oh Stephen , Shukla Deepak , Valyi-Nagy Tibor 
Published: February 2021

Abstract
Context.—Nectin-1 is an immunoglobulin-like adhesion molecule that is widely expressed in epithelial tissues and participates in the formation of adherens junctions. Reduced expression of nectin-1 has been reported in invasive carcinomas of the human skin.
Objective.—To determine the pattern of nectin-1 expression in the normal, dysplastic, and neoplastic human uterine cervix.
Design.—This retrospective study was performed using immunohistochemistry of specimens of normal mucosa (n = 18) and preneoplastic and neoplastic conditions of the human uterine cervix including squamous dysplasia and invasive uterine cervical squamous carcinoma (n = 23). All specimens were graded according to intensity of cytoplasmic staining (0 = no staining; 4 = strongest intensity).
Results.—Strong widespread cytoplasmic nectin-1 reactivity was found in normal uterine cervical squamous and endocervical mucosa (mean grade = 2.63). In contrast, uterine cervical and endocervical stroma showed minimal to absent staining (mean grade = 0.58). There was a significant difference in staining intensity between normal mucosa versus stroma (P &lt; .001, Wilcoxon matched pairs– signed ranks test). All squamous dysplasia and carcinoma specimens displayed strong cytoplasmic nectin-1 staining (mean grade = 3.08). The advancing edge of these carcinomas demonstrated significantly decreased or absent expression of nectin-1 (mean grade = 1.39) with significant difference in staining intensity at the center of invasive tumors versus the advancing edge (P = .004, Wilcoxon matched pairs–signed ranks test).
Conclusions.—Normal squamous mucosa, dysplasia, and invasive carcinomas of the human uterine cervix stain strongly with nectin-1, and this staining is reduced or absent in the advancing edge of invasive tumors. These findings suggest that down-regulation of nectin-1 may be associated with the loss of cell-to-cell adhesion at the advancing edge of invasive squamous carcinomas of the human uterine cervix.
Review of Pineal Anlage Tumor With Divergent Histology
Authors: Berns Stephen , Pearl Gary 
Published: February 2021

Abstract
Pineal anlage tumor is an extremely rare tumor that is not listed in the 2000 World Health Organization Classification of nervous system tumors. It has been defined as a primary pineal tumor with both neuroepithelial and ectomesenchymal differentiation and without endodermal differentiation. We review the literature on this tumor, including the clinical presentation, gross pathology, histopathology, immunohistochemistry, differential diagnosis, and prognosis.
Gastrointestinal Stromal Tumors: Review on Morphology, Molecular Pathology, Prognosis, and Differential Diagnosis
Authors: Miettinen Markku , Lasota Jerzy 
Published: February 2021

AbstractContext.—Gastrointestinal stromal tumors (GISTs) are specific, generally Kit (CD117)-positive, mesenchymal tumors of the gastrointestinal tract encompassing a majority of tumors previously considered gastrointestinal smooth muscle tumors. They are believed to originate from interstitial cells of Cajal or related stem cells.Objective.—To review current clinicopathologically relevant information on GIST.Data Sources.—Literature in Medline and authors' own experience.Conclusions.—GISTs usually occur in older adults (median age 55–60 years) and rarely in children in the second decade (&lt;1%) throughout the gastrointestinal tract: 60% in stomach, 35% in small intestine, and less than 5% in rectum, esophagus, omentum, and mesentery; most GISTs in the latter 2 sites are metastatic. Five percent of GISTs occur in patients with neurofibromatosis type 1 syndrome (multiple small intestinal tumors) and in Carney triad (gastric epithelioid GISTs in young females). Familial GISTs occur in patients with inheritable germline Kit or platelet-derived growth factor receptor alpha (PDGFRA) mutations. Histologically GISTs vary from spindle cell tumors to epithelioid and pleomorphic tumors. Most GISTs (95%) express Kit (CD117), CD34 (70%), and heavy caldesmon (80%), whereas 25% are positive for smooth muscle actin and less than 5% for desmin. Tumor size and mitotic activity are best predictive prognostic features; small intestinal tumors behave more aggressively than gastric tumors with similar parameters. Mutually exclusive gain-of-function Kit or PDGFRA mutations occur in a majority of GISTs representing in-frame deletions, point mutations, duplications and insertions. Mutations in Kit juxtamembrane domain (exon 11) are the most common in GISTs of all sites, whereas rare Kit extracellular domain (exon 9) Ala502-Tyr503 duplication is specific for intestinal GISTs. Mutations in PDGFRA have been identified in juxtamembrane (exon 12) and tyrosine kinase domains (exons 14 and 18), nearly exclusively in gastric GISTs, mostly in epithelioid variants. Some Kit and PDGFRA mutations have a prognostic value. Kit/PDGFRA tyrosine kinase inhibitor imatinib has been successfully used in the treatment of metastatic GISTs for more than 5 years. However, primary and acquired secondary resistance linked to certain types of Kit and PDGFRA mutations is limiting long-term success necessitating the use of alternative treatments.
Interobserver Agreement on Microfollicles in Thyroid Fine-Needle Aspirates
Authors: Renshaw Andrew A. , Wang Edward , Wilbur David , Hughes Jonathan H. , Haja Jennifer , Henry Michael R. 
Published: February 2021

Abstract
Context.—Although microfollicles are a well-known feature of follicular neoplasms in fine-needle aspirates of the thyroid, the level of agreement about classifying groups as microfollicles is not known.
Objective.—To determine what features are present in groups that are consistently classified as microfollicles.
Design.—We showed 45 small groups of follicular cells each composed of fewer than 50 cells from fine-needle aspirates of the thyroid to 12 members of the College of American Pathologists Cytopathology Committee, who then classified the groups into microfollicles, macrofollicles, and indeterminate groups.
Results.—Twenty groups were consistently classified as microfollicles, 7 groups as macrofollicles, and 18 groups as indeterminate. Cases that were consistently classified as microfollicles were composed of fewer than 15 cells (19/ 20 cases), were arranged in a circle with a lumen (13/20 cases) that was at least two-thirds complete (12/20 cases), and were flat (18/20 cases). Cases that were classified as macrofollicular had between 8 and 35 cells, were arranged in sheets composed of at least 15 cells (5/7 cases) or rows of 8 cells (2/7 cases), and were flat (7/7 cases). In contrast, cases that were indeterminate were composed of either 3-dimensional groups (5/18 cases), flat groups of fewer than 10 cells (11/18 cases), or single cells (1/18 cases).
Conclusion.—Not all small groups of follicular cells are consistently classified as microfollicles, and some are more often classified as macrofollicles. The criteria described here for reproducible microfollicles (&lt;15 cells, arranged in a circle that is at least two-thirds complete, and flat) may help improve the agreement in classification of microfollicles and lead to more consistent classification of thyroid fine-needle aspirates.
Hepatic Mesenchymal Hamartoma: A Short Review
Authors: Siddiqui Masood A. , McKenna Barbara J. 
Published: February 2021

Abstract
Hepatic mesenchymal hamartoma is a hamartomatous growth of mesenchymal tissue in the liver of uncertain etiology. It is a space-occupying lesion that can potentially compress adjacent organs resulting in various complications including death. Hepatic mesenchymal hamartoma is characterized by proliferation of variably myxomatous mesenchyme and malformed bile ducts. The differential diagnosis includes other pediatric hepatic masses. The diagnosis is typically made during infancy, and complete resection is invariably curative.
Granulocytic Sarcoma of the Small Intestine
Authors: Kohl Shane K. , Aoun Patricia 
Published: February 2021

Abstract
Granulocytic sarcoma is an extramedullary tumor of myeloblasts and/or immature myeloid cells, which can develop at any anatomic site and is often a forerunner to the development of acute myelogenous leukemia. Granulocytic sarcoma of the gastrointestinal tract most frequently involves the small intestine and most often presents with abdominal pain and obstruction. Pathologists must consider granulocytic sarcoma in any mass of unknown origin with a diffusely infiltrating population of tumor cells, as the diagnosis is often initially unrecognized, especially in nonleukemic patients. Multiple ancillary modalities are available to assist pathologists in making the correct diagnosis so that appropriate therapy can be initiated.
An Algorithmic Approach to the Brain Biopsy—Part II
Authors: Prayson Richard A. , Kleinschmidt-DeMasters B. K. 
Published: February 2021

Abstract
Context.—The formulation of appropriate differential diagnoses for a slide is essential to the practice of surgical pathology but can be particularly challenging for residents and fellows. Algorithmic flow charts can help the less experienced pathologist to systematically consider all possible choices and eliminate incorrect diagnoses. They can assist pathologists-in-training in developing orderly, sequential, and logical thinking skills when confronting difficult cases.
Objective.—To present an algorithmic flow chart as an approach to formulating differential diagnoses for lesions seen in surgical neuropathology.
Design.—An algorithmic flow chart to be used in teaching residents.
Results.—Algorithms are not intended to be final diagnostic answers on any given case. Algorithms do not substitute for training received from experienced mentors nor do they substitute for comprehensive reading by trainees of reference textbooks. Algorithmic flow diagrams can, however, direct the viewer to the correct spot in reference texts for further in-depth reading once they hone down their diagnostic choices to a smaller number of entities. The best feature of algorithms is that they remind the user to consider all possibilities on each case, even if they can be quickly eliminated from further consideration.
Conclusions.—In Part II, we assist the resident in arriving at the correct diagnosis for neuropathologic lesions containing granulomatous inflammation, macrophages, or abnormal blood vessels.
Light-Chain–Mediated Acute Tubular Interstitial Nephritis: A Poorly Recognized Pattern of Renal Disease in Patients With Plasma Cell Dyscrasia
Authors: Gu Xin , Herrera Guillermo A. 
Published: February 2021

Abstract
Context.—Acute renal failure may be the first clinical presentation in patients with plasma cell dyscrasia. Recognition of the unusual interstitial inflammatory lesion associated with monoclonal light chains and renal failure described herein is important to guide clinicians in requesting appropriate tests to confirm plasma cell dyscrasia and providing adequate treatment.
Objective.—To describe an unusual pattern of tubular interstitial nephritis in patients with underlying plasma cell dyscrasia characterized by an interstitial inflammatory reaction associated with deposition of light chains along tubular basement membranes.
Design.—Eight cases of light-chain–mediated acute tubular interstitial nephritis were identified from the archives of 4296 kidney biopsy specimens. In all cases, routine light microscopic examination, direct immunofluorescence, and electron microscopic examination were performed. Ultrastructural immunogold labeling was performed in specimens with inconclusive findings and in specimens from patients with no clinical history of plasma cell dyscrasia.
Results.—All patients presented with acute renal failure. Light microscopy revealed acute tubular interstitial nephritis. In some of the cases, direct immunofluorescence and electron microscopy failed to show definitive evidence of light-chain deposition along tubular basement membranes. Ultrastructural immunogold labeling aided the demonstration of monotypical light chains along some tubular basement membranes. No light chains were present in other renal compartments.
Conclusions.—Accumulation of light chains along tubular basement membranes may induce an interstitial process that mimics acute tubular interstitial nephritis. Recognition of this unusual pattern of renal disease in patients with plasma cell dyscrasia requires ancillary diagnostic techniques.
Patient Safety in the Clinical Laboratory: A Longitudinal Analysis of Specimen Identification Errors
Authors: Wagar Elizabeth A. , Tamashiro Lorraine , Yasin Bushra , Hilborne Lee , Bruckner David A. 
Published: February 2021

Abstract
Context.—Patient safety is an increasingly visible and important mission for clinical laboratories. Attention to improving processes related to patient identification and specimen labeling is being paid by accreditation and regulatory organizations because errors in these areas that jeopardize patient safety are common and avoidable through improvement in the total testing process.
Objective.—To assess patient identification and specimen labeling improvement after multiple implementation projects using longitudinal statistical tools.
Design.—Specimen errors were categorized by a multidisciplinary health care team. Patient identification errors were grouped into 3 categories: (1) specimen/requisition mismatch, (2) unlabeled specimens, and (3) mislabeled specimens. Specimens with these types of identification errors were compared preimplementation and postimplementation for 3 patient safety projects: (1) reorganization of phlebotomy (4 months); (2) introduction of an electronic event reporting system (10 months); and (3) activation of an automated processing system (14 months) for a 24-month period, using trend analysis and Student t test statistics.
Results.—Of 16 632 total specimen errors, mislabeled specimens, requisition mismatches, and unlabeled specimens represented 1.0%, 6.3%, and 4.6% of errors, respectively. Student t test showed a significant decrease in the most serious error, mislabeled specimens (P &lt; .001) when compared to before implementation of the 3 patient safety projects. Trend analysis demonstrated decreases in all 3 error types for 26 months.
Conclusions.—Applying performance-improvement strategies that focus longitudinally on specimen labeling errors can significantly reduce errors, therefore improving patient safety. This is an important area in which laboratory professionals, working in interdisciplinary teams, can improve safety and outcomes of care.