Morphological Findings Research Articles

Spider bite presenting as fever, macrophage activation syndrome and a skin ulcer

Introduction: Fever of unknown origin (FUO) refers to a condition of prolonged increased body temperature, without identified causes. The most common cause of FUO worldwide are infections; arthropod bites (loxoscelism) should be considered in view of the spread of the fiddleback spider. Loxoscelism can present in a cutaneous form (a necrotic cutaneous ulcer) or in a systemic form with fever, haemolytic anaemia, rhabdomyolysis and, rarely, macrophage activation syndrome (MAS). For this suspicion, it is important to have actually seen the spider. Case description: A 71-year-old man was admitted to our department because of intermittent fever, arthralgia and a necrotic skin lesion on his right forearm that appeared after gardening. Laboratory tests were negative for infectious diseases, and several courses of antibiotics were administered empirically without clinical benefit. Whole-body computed tomography showed multiple colliquative lymphadenomegalies, the largest one in the right axilla, presumably of reactive significance. A shave biopsy of the necrotic lesion was performed: culture tests were negative and histological examination showed non-specific necrotic material, so a second skin and lymph node biopsy was performed. The patient developed MAS for which he received corticosteroid therapy with clinical/laboratory benefit. Cutaneous and systemic loxoscelism complicated by MAS was diagnosed. Subsequently, the second biopsy revealed morphological and immunophenotypic findings consistent with primary cutaneous anaplastic large cell lymphoma (PC-ALCL). Conclusions: Skin lesions and lymphadenomegalies of unknown origin should always be biopsied. It is very common to get indeterminate results, but this does not justify not repeating the procedure to avoid misdiagnosis.

Novel CRTC1::MRTFB(MKL2) Gene Fusion Detected in Myxoid Mesenchymal Neoplasms With Myogenic Differentiation Involving Bone and Soft Tissues

Appropriate classification of fusion-driven bone and soft tissue neoplasms continues to evolve, often relying on the careful integration of morphologic findings with immunohistochemical, molecular, and clinical data. Herein, we present 3 cases of a morphologically distinct myxoid mesenchymal neoplasm with myogenic differentiation and novel CRTC1::MRTFB (formerly MKL2) gene fusion. Three tumors occurred in 1 male and 2 female patients with a median age of 72 years (range: 28-78). Tumors involved the left iliac bone, the right thigh, and the left perianal region with a median size of 4.0 cm (4.0-7.6 cm). Although 1 tumor presented as an incidental finding, the other 2 tumors were noted, given their persistent growth. At the time of the last follow-up, 1 patient was alive with unresected disease at 6 months, 1 patient was alive without evidence of disease at 12 months after surgery, and 1 patient died of disease 24 months after diagnosis. On histologic sections, the tumors showed multinodular growth and were composed of variably cellular spindle to round-shaped cells with distinct brightly eosinophilic cytoplasm embedded within a myxoid stroma. One tumor showed overt smooth muscle differentiation. Cytologic atypia and mitotic activity ranged from minimal (2 cases) to high (1 case). By immunohistochemistry, the neoplastic cells expressed focal smooth muscle actin, h-caldesmon, and desmin in all tested cases. Skeletal muscle markers were negative. Next-generation sequencing detected nearly identical CRTC1::MRTFB gene fusions in all cases. We suggest that myxoid mesenchymal tumors with myogenic differentiation harboring a CRTC1::MRTFB fusion may represent a previously unrecognized, distinctive entity that involves soft tissue and bone. Continued identification of these novel myxoid neoplasms with myogenic differentiation will be important in determining appropriate classification, understanding biologic potential, and creating treatment paradigms.

Morphological and clinical findings in placentas and newborns with a history of tobacco, alcohol, and other substance abuse during pregnancy.

Exposure to toxins during pregnancy is the main modifiable behavior that affects the placenta and, consequently, the fetus. In particular, smoking is a recognized risk factor for negative outcomes. Our study pretended to examine gross and microscopic placental features in women who reported exposure to tobacco, alcohol, or other psychoactive substances. In this observational case-control study, we collected 706 placentas to assess precise substance exposure histological-interaction features of in the placenta. We examined gross and microscopic placental features, and then recorded maternal and newborn clinical conditions. We found that 4.8% of mothers admitted to consumption of some type of (harmful) substance. The most common pre-existing maternal condition was obesity (20.3%); predominant complications included amniotic infection (32.3%), urinary tract infection (14.5%) and hypertensive disorders of pregnancy (14.5%). In newborns, we discovered positive associations as respiratory distress syndrome. Macroscopically, exposed mothers had heavier placentas, more true knots, and single umbilical artery; microscopically, they were more likely to exhibit fetal vascular malperfusion (FVM). Until our present study, no research linked umbilical cord defects to toxic substance exposure; our study results do confirm association with adverse outcomes in neonates and alterations in the neuro-cardio-placental circuit through FVM. The results are confirming the importance of this modifiable risk factor and how its presence may potentially affect the course of pregnancy, as well as the health of both mother and child.

Identifying a Case of an Atenolol-induced Papulosquamous Eruption

While beta-adrenergic blocking agents (beta blockers) are generally safe, their incidence of medication-induced cutaneous eruptions remain under-recognized in the primary care setting. The adverse dermatologic effects of these medications may arise in the days to years following drug initiation, contributing to its delayed diagnosis and management. Here we report a case of a papulosquamous drug eruption in an older adult due to atenolol. We also discuss pertinent morphologic findings, diagnostic methods, management, and how to distinguish this type of eruption from other papulosquamous disorders.

Histologic Features of Mycobacterial Spindle Cell Pseudotumors: A Multi-institutional Clinicopathologic Analysis of 14 Cases.

Mycobacterial spindle cell pseudotumors (MSPs) are a rare and diagnostically challenging manifestation of non-tuberculous mycobacterial (NTM) infections. Proper recognition of these pseudotumors is important because they are treatable and benign. In this study, we evaluated the morphologic patterns of MSPs to improve their pathologic identification. Clinical and morphologic features of 14 MSPs were analyzed. Histologic factors evaluated included the architectural growth pattern of spindled or epithelioid macrophages, granulomas and their location within the lesion, neutrophilic microabscesses, multinucleated giant cells, necrosis, and effacement of background tissue. The composition of inflammatory infiltrates, organism density by acid-fast staining, and stromal changes were also assessed. In addition, 8 of 14 cases underwent molecular microbiology identification by a clinical amplicon-sequencing assay for non-tuberculous mycobacteria. MSP sites included 2 bowel, 10 lymph nodes, 1 liver, and 1 extremity. Cases with available clinical history (n=10) all occurred in immunocompromised patients. All demonstrated effacement of normal structures with spindled cells arranged in a storiform or fascicular architectural pattern. In addition, all cases showed lymphocytic inflammation, with prominent concurrent neutrophilic inflammation in 50% (7/14) of cases. Other morphologic findings included foamy histiocytes (64%, 9/14), peripherally situated granulomas (21%, 3/14), and neutrophilic microabscesses (21%, 3/14). All tested cases were positive for NTM by PCR methods. Mycobacterium avium was the most commonly isolated pathogen (6/8). Mycobacterial spindle cell pseudotumors show predominantly spindled morphology that may be mistaken as a neoplasm. Surgical pathologists who evaluate lymph nodes, soft tissue, and gastrointestinal tissues should be aware of this spindled tumefactive phenomenon in the setting of immunocompromised patients. Recognition of key morphologic features of neutrophilic inflammation, peripheral granulomas, or foamy histiocytes within a spindled lesion can help guide the pathologist to a correct diagnosis of an inflammatory process secondary to infection rather than a spindle cell neoplasm. Accurate diagnosis to facilitate appropriate antimicrobial and/or surgical therapy requires a comprehensive evaluation combining clinical, histopathologic, and microbiological findings.

Evaluation of tubal patency based on peak injection pressure in four-dimensional hysterosalpingo-contrast sonography among infertile females: a preliminary study.

Although the application of four-dimensional hysterosalpingo-contrast sonography (4D-HyCoSy) has relatively good diagnostic accuracy for assessing the patency of the fallopian tubes, the evaluation process mainly relies on morphological findings of the fallopian tubes and pelvic cavity. The purpose of this study was to explore the relationship of peak injection pressure during 4D-HyCoSy and tubal patency to provide a quantitative indicator for the evaluation of fallopian tube patency. This study included infertile patients who underwent 4D-HyCoSy and laparoscopic chromopertubation (LC) between 2020 and 2022, with LC serving as the reference test for assessing tubal patency. For the HyCoSy procedure, the ultrasound contrast agent was injected automatically using a liquid injection machine, and real-time pressure values were recorded. Patients were classified based on tubal patency status in LC as bilaterally patent, unilaterally patent, or bilaterally nonpatent. The average peak injection pressure and contrast agent volume of different groups were compared. Receiver operating characteristic (ROC) curve analysis was employed to determine the cutoff value. A total of 268 infertile patients were enrolled in the study. With LC as the standard examination, the sensitivity and specificity of 4D-HyCoSy in diagnosing nonpatent fallopian tubes were 91.1% and 95.1%, respectively. In general, peak injection pressure was observed to gradually increase as tubal patency decreased (P<0.001), with average peak injection pressures of 233.5±66.3, 338.8±99.8, and 469.6±63.1 mmHg in the bilaterally patent, unilaterally patent, and bilaterally nonpatent groups, respectively. The volume of contrast agent used in patients in the bilaterally nonpatent group was significantly lower than that in the other two groups (P<0.01), with average volumes of 22.7±6.3, 24.3±9.3, and 18.9±9.2 mL, respectively. When one fallopian tube was patent, the area under the curve (AUC) for distinguishing obstruction from patency of the other fallopian tube was 0.827, with a sensitivity of 79.8% and a specificity of 74.3% (cutoff value: 254.3 mmHg). Similarly, when one fallopian tube was nonpatent, the AUC was 0.866, with a sensitivity of 90.6% and a specificity of 78.3% (cutoff value: 401.3 mmHg). Peak injection pressure during 4D-HyCoSy demonstrates promising diagnostic performance in evaluating fallopian tube patency in infertile patients.

Mitral Geometry on the Mechanism of Left Ventricular Outflow Tract Obstruction in Hypertrophic Cardiomyopathy

The mechanism of left ventricular outflow tract obstruction (LVOTO) is complex in hypertrophic cardiomyopathy (HCM). We aimed to evaluate the impact of mitral valve geometry on LVOTO by echocardiography. The study population comprised 177 consecutive patients with HCM. Morphological findings of left ventricular hypertrophy and LVOTO-related abnormalities were assessed by comprehensive transthoracic echocardiography. Aortomitral angle, mitral leaflet length, and coaptation height were measured and analyzed at rest. Multivariable stepwise forward logistic regression analysis was performed to identify geometric predictors of LVOTO. One hundred thirty-seven patients had an LVOT gradient ≥30mm Hg. Multivariable logistic regression showed that aortomitral angle (odds ratio [OR], 0.89; 95% CI, 0.83-0.95, P<.001), coaptation height (OR, 1.96; 95% CI, 1.41-2.72, P<.001), and accessory mitral valve chordae tendineae (OR, 13.1; 95% CI, 4.32-39.95; P<.001) were independently associated with LVOTO. Receiver operating characteristic analysis showed that the area under the curve of mitral coaptation height was higher (area under the curve=0.815) than the other 2 indicators (P<.05). Mitral coaptation height, aortomitral angle, and accessory mitral valve chordae tendineae were important predictors of SAM and LVOTO in HCM independent of septal hypertrophy.

How I diagnose systemic mastocytosis.

Systemic mastocytosis (SM) is a neoplasm of mast cells (MCs) characterized by their proliferation in extracutaneous organs. Systemic mastocytosis includes several entities with different clinical courses and prognoses. The rarity of this disease and the diversity of clinical and morphologic presentation make the diagnosis of SM very challenging. The aim of this review is to share our approach to the diagnosis of SM. We present 4 cases that highlight the spectrum of clinical and laboratory features of SM and outline the diagnostic process with an emphasis on morphology. Pathology and laboratory medicine play a key role in investigation of SM, as correct diagnosis requires integration of morphologic, molecular, and serologic findings. In addition to awareness of microscopic findings in SM, a pathologist must keep abreast with an expanding menu of ancillary studies, particularly molecular testing. Systemic mastocytosis is a challenging diagnosis that requires not only a demonstration of a clonal proliferation of MCs but also a correct subclassification based on the recently updated criteria.

The Contribution of Vessel Wall Magnetic Resonance Imaging to the Diagnosis of Primary and Secondary Central Nervous System Vasculitis.

To describe high-resolution brain vessel wall MRI (VW-MRI) patterns and morphological brain findings in central nervous system (CNS) vasculitis patients. Fourteen patients with confirmed CNS Vasculitis from two tertiary centers underwent VW-MRI using a 3T scanner. The images were reviewed by two neuroradiologists to assess vessel wall enhancement characteristics and locations. Fourteen patients were included (six females; average age 48 ± 19 years). Diagnoses included primary CNS vasculitis (PCNSV) in six patients and secondary CNS vasculitis (SCNSV) in eight, half of which were infection-related. Thirteen patients showed vessel wall enhancement, which was intense in eleven patients (84.6%) and concentric in twelve (92.3%), affecting the anterior circulation in nine patients (69.2%), posterior in two patients (15.4%), and both circulations in two patients (15.4%). The enhancement patterns were similar across different CNS vasculitis types. DWI changes corresponded with areas of vessel wall enhancement in 77% of patients. Conclusions: CNS vasculitis is often associated with intense, concentric vessel wall enhancement in VW-MRI, especially in the anterior circulation. The consistent presence of DWI alterations in affected territories suggests a possible link to microembolization or hypoperfusion. These imaging findings complement parenchymal brain MRI and MRA/DSA data, potentially increasing the possibility of a clinical diagnosis of CNS vasculitis.

Oncocytic Lesions of Salivary Glands: Morphological, Immunohistochemical, and Molecular Findings.

The fifth edition of the World Health Organization (WHO) classification introduces new diagnostic methods based on genetic alterations, providing insight into the molecular basis of lesions. As a result, the classification system has evolved, new entities have been introduced, and existing entities have been reclassified. Oncocytic lesions of salivary glands are a group of neoplastic conditions characterized bythe presence ofoncocytic cells. These lesions present a diagnostic challenge due to their overlapping histological features. Therefore, a comprehensive evaluation, including morphological, immunohistochemical, and molecular analysis, is crucial for accurate diagnosis and appropriate management. Accurate classification of salivary gland pathologies is essential for selecting the appropriate treatment methods and predicting outcomes. The introduction of new therapeutic approaches, such as targeted therapies for malignant salivary gland tumors, has improved patient outcomes. However, to effectively implement these therapies in clinical practice, a clear classification of lesions is necessary.

Proposal of a classification of cannulation damage in vascular access grafts based on clinical, ultrasound, and microscopic observations.

Arteriovenous grafts (AVGs) serve as an alternative to native arteriovenous fistulas (AVFs) in the context of hemodialysis patient life planning. AVGs are more susceptible to developing outflow stenosis (due to intimal hyperplasia), thrombosis, and infections. However, an often overlooked contributor to AVG failure is cannulation damage. The objective of this paper is to assess the impact of cannulations on AVGs. We aim to establish a classification of AVG damage by comparing clinical data and ultrasound images with microscopic morphological findings obtained from explanted grafts. This study is conducted at a single center. We included all patients who underwent AVG creation between 2011 and 2019. Comprehensive data on clinical history, follow-up, and complications were collected and reviewed. Duplex ultrasound (DUS) characteristics were documented, and all grafts explanted during the analysis period underwent optical microscopy evaluation. Finally, clinical data, along with DUS and microscopic findings, were integrated to derive a damage classification. During the study period, 247 patients underwent 334 early cannulation AVGs. The median follow-up duration was 714 days (IQR 392, 1195). One hundred eleven (33%) grafts were explanted. Clinical data and DUS findings were utilized to formulate a four-grade classification system indicating increasing damage. Cannulation damage alone does not solely account for AVG failure. It results from a biological host-mediated process that promotes the growth of intimal hyperplasia at the cannulation sites. This process is not clinically significant within the initial 2 years after AVG creation.

Genetic Analyses of Primary Liver Cancer Cell Lines: Correspondence With Morphological Features of Original Tumors.

Advancements in genetic analysis technologies have led to establishment of molecular classifications systems for primary liver cancers. The correlation between pathological morphology and genetic mutations in hepatocellular carcinoma (HCC) is becoming increasingly evident. To construct appropriate experimental models, it is crucial to select cell lines based on their morphology and genetic mutations. In this study, we conducted comprehensive genetic analyses of primary liver cancer cell lines and examined their correlations with morphology. Thirteen primary liver cancer cell lines established in our Department were investigated. Eleven cell lines were HCC cell lines, whereas 2 were combined hepatocellular-cholangiocarcinoma (CHC) cell line characteristics. Whole exome sequencing and fusion gene analyses were conducted using a next generation sequencing platform. We also examined correlations between cell mutations and morphological findings and conducted experiments to clarify the association between morphological findings and genetic alterations. Mutations in TP53, HMCN1, PCLO, HYDIN, APOB, and EYS were found in 11, 5, 4, 4, 3, and 3 cell lines, respectively. CTNNB1 mutation was not identified in any cell line. The original tumor of four cell lines (KYN-1, KYN-2, KYN-3, and HAK-6) showed morphologically macrotrabecular massive patterns and these cell lines harbor TP53 mutations. Two cell lines (KYN-2 and KMCH-2) showed an extremely high tumor mutation burden. These two cell lines possess ultra-mutations associated with DNA repair and/or DNA polymerase. The study identified correlations between morphological findings and genetic mutations in several HCC cell lines. Cell lines with unique genetic mutations were found. This information will be a valuable tool for the selection of suitable experimental models in HCC research.

A pilot study on Langerhans cells in keratoconus patients by in vivo confocal microscopy before and after corneal cross-linking and correlation with eye rubbing

PurposeThe aim of this study was to investigate the corneal microstructure and Langerhans cells using in vivo confocal microscopy in keratoconus patients before and after cross-linking, and to correlate the morphologic findings with clinical and patient-reported outcomes, including eye rubbing (ER) behavior. MethodsPatients with progressive keratoconus undergoing iontophoresis-assisted epithelium-on cross-linking (I-CXL) were consecutively enrolled. In vivo confocal microscopy was performed before and 6 months after treatment. Patients were asked to quantify their ER behavior on a Visual Analogue Scale (VAS) and completed the Keratoconus Outcomes Research Questionnaire and the Ocular Surface Disease Index questionnaires at the same time points. Visual acuity, tear osmolarity, topography, aberrometry, and pachymetry of both eyes were assessed. ResultsThirteen patients were included in this pilot study. Preoperatively, the mean Langerhans cells density was 35,615 cells per mm2, and the median morphology was 3. The mean ER VAS before treatment was 7,077 out of 10. The ER VAS showed significant positive correlations with both Langerhans cells density and morphology of the study eye. After treatment, a statistically significant reduction in ER VAS and in Langerhans cells variables was observed. The mean sub-basal plexus nerve density was comparable to pre-operative values 6 months after I-CXL. ConclusionsBased on this preliminary evidence, the presence of high density of mature Langerhans cells in the central cornea of keratoconus patients and its correlation with eye rubbing support the role of inflammation in keratoconus. The reduction in these markers after treatment may suggest a potential of CXL in moderating immune-related inflammation and eye rubbing in the medium term.

Redescription and a significant range extension of Rhacophorus napoensis Li, Liu, Yu &amp;amp; Sun, 2022 (Amphibia, Anura, Rhacophorinae) with the first record from Vietnam

The Napo Treefrog Rhacophorus napoensis was described based on five male specimens from Napo County, Baise City, Guangxi Autonomous Region, China. Herein, we report on new findings and a range extension of this species based on an examination of preserved specimens collected from Bac Giang and Nghe An provinces, Vietnam. Futhermore, molecular analyses of specimens Rhacophorus spp. previously identified as R. rhodopus that were reported in Bac Giang, Nghe An as well as Thanh Hoa, and Ha Tinh provinces based on mitochondrial DNA supported the morphological findings. The Vietnam specimens have a pairwise divergence of less than 2% from those of the type series of Rhacophorus napoensis (based on the 16s rRNA mtDNA gene). Based on the new information, we confirm the presence of R. napoensis in Vietnam and update the diagnostic characters of this species and distribution. We suggest the species should be considered as of Least Concern (LC) following the IUCN’s Red List categories. Further studies reassessing the populations of the Rhacophorus bipunctatus complex are required.

Inflammatory Myofibroblastic Tumor of the Esophagus and Stomach Successfully Treated With ALK Inhibitor in a Pediatric Patient: A Case Report and Concise Review of Literature.

An inflammatory myofibroblastic tumor (IMT) is a rare mesenchymal neoplasm of borderline malignant potential. Nearly half of all IMTs have rearrangement of anaplastic lymphoma kinase (ALK) locus on chromosome 2p23 which can be treated with targeted therapy. Herein, we describe an unusual presentation of IMT involving an anatomical region rarely implicated in this disease process. A 15-year-old male patient came to the ER with dysphagia and coffee ground emesis. On esophagogastroscopy, a nodular luminal obstructing 30 × 50 mm mass in the lower esophagus was found, which was continuous with a large, partially circumferential gastric mass extending from the mid-body to the proximal antrum. Biopsies from esophageal and gastric masses revealed submucosal lesions composed of cytologically bland spindle and epithelioid cells, intermingled with inflammatory infiltrate, for which several immunohistochemical (IHC) stains were performed. The molecular study demonstrated ATIC::ALK fusion. Based on morphological, IHC, and molecular study findings, the diagnosis of ALK-positive IMT was rendered. Because surgical excision was deemed infeasible, the patient was started on ALK-inhibiting therapy with crizotinib. The patient responded well with no evidence of residual or recurrent disease on follow-up imaging or surveillance esophagogastroduodenoscopy. Crizotinib was ultimately discontinued after 10 months of therapy, and the patient continues to undergo surveillance imaging for monitoring of disease burden.

Diaphragmatic morphological post-mortem findings in critically ill COVID-19 patients: an observational study.

Our study investigates the post-mortem findings of the diaphragm's muscular structural changes in mechanically ventilated COVID-19 patients. Diaphragm samples of the right side from 42 COVID-19 critically ill patients were analyzed and correlated with the type and length of mechanical ventilation (MV), ventilatory parameters, prone positioning, and use of sedative drugs. The mean number of fibers was 550±626. The cross-sectional area was 4120±3280 μm2, while the muscular fraction was 0.607±0.126. The overall population was clustered into two distinct populations (clusters 1 and 2). Cluster 1 showed a lower percentage of slow myosin fiber and higher fast fiber content than cluster 2, 68% versus 82%, p<0.00001, and 29.8% versus 18.8%, p=0.00045 respectively. The median duration of MV was 180 (41-346) hours. In cluster 1, a relationship between assisted ventilation and fast myosin fiber percentage (R2=-0.355, p=0.014) was found. In cluster 2, fast fiber content increased with increasing the length of the controlled MV (R2=0.446, p=0.006). A high grade of fibrosis was reported. Cluster 1 was characterized by fibers' atrophy and cluster 2 by hypertrophy, supposing different effects of ventilation on the diaphragm but without excluding a possible direct viral effect on diaphragmatic fibers.

Range extension and expanded description of Micryletta hekouensis Liu, Hou, Mo &amp;amp; Rao, 2021 (Amphibia, Anura, Microhylidae), with comments on Micryletta of Northern Vietnam

The Paddy frog species Micryletta hekouensis was described based on only two specimens from Nanxi Village, Nanxi Town, Hekou County, Honghe Prefecture, Yunnan Province, China. Herein, we report on new findings and a range extension of this species based on a re-examination of preserved specimens deposited in Duy Tan University (DTU) and Zoological Museum of Lomonosov Moscow State University (ZMMU) collected from Vietnam. All new specimens were previously identified as Micryletta cf. inornata or M. cf. steinegeri. Molecular analyses based on mitochondrial DNA supported the morphological findings. The newly identified specimens have a pairwise divergence of only 0.7% from those of the type series of M. hekouensis, based on the 16s rRNA mtDNA gene. Based on the new information, we confirm the presence of M. hekouensis in Vietnam and update the diagnostic characters of this species and its distribution. We suggest the species should be considered as Near Threatened (NT) following the IUCN’s Red List categories. Further studies reassessing the populations of the Micryletta inornata complex in the Indochinese Region (including Vietnam, Laos, Cambodia, and Thailand) are required.

Imaging in headache

Headache is worldwide one of the leading reasons to consult ageneral practitioner or aneurologist. In addition to the medical history and results of laboratory parameters, imaging represents one of the most important diagnostic steps. As there is amyriad of possible causes, it is nearly impossible to cover the whole spectrum of this topic. This article summarizes the most important morphological imaging findings and their pitfalls.

Difficulties in Differentiation of Endolymphatic Sac Tumor That Extends Into Pontocerebellar Angle from Metastatic Tumors

Endolymphatic Sac Tumor is a local aggressive tumor that grows slowly, associated with Von-Hippel-Lindau disease and originated from endolymphatic canal. A 64-year-old male patient with VHL disease admitted to the neurosurgery department of our hospital and presented pain behind the ear and loss of sensation on the cheek. Cranial magnetic resonance imaging revealed an aggressive tumor located in the middle ear and left acoustic canal and extending to the pontocerebellar angle that eroded the mastoid and temporal bones. Histopathological examination of the lesion revealed a simple cuboidal epithelium forming glandular and papillary structures. The patient diagnosed with endolymphatic sac tumor as the presence of the morphological findings, positive staining with immunohistochemical markers such as Vimentin, NSE, EMA, PAX8, Cytokeratin 7. Our case showed neuroectodermal origin, which is even rare for von Hippel-Lindau disease, and has been discussed with histopathological findings and differential diagnosis.

Hematuria Due to Possible Histoplasma-Associated Urinary Bladder Pseudotumor With Negative Serologic and Urine Antigen Testing

Abstract Histoplasma capsulatum is a ubiquitous dimorphic fungus causing multiple infectious syndromes, ranging from subclinical to severe disseminated disease. We present an unusual case of hematuria due to pedunculated urinary bladder mass in an immunocompetent host. Although the gold standard for diagnosis of histoplasmosis is through demonstration of characteristic yeast forms on histopathologic examination of infected tissue, or observation of typical mycelial growth in culture of clinical specimens, investigational multiplex polymerase chain reaction of formalinized tissue was helpful in this case due to conflicting serologic testing, equivocal morphologic findings on histopathologic examination and, surprisingly, a negative urine Histoplasma antigen despite anatomically proximal location within the urinary bladder. Although antigen immunoassay and serology are commonly used proxy diagnostics in Histoplasma-associated disease, varying performance characteristics in certain disease states, such as cases of locally proliferative infection mimicking neoplastic growth similar to this report, may lead to elusive diagnosis.