Lymph Glands Research Articles

Morphological Characteristics of Genital Organ-Associated Lymphoid Tissue in the Vaginal Vestibule of Goats and Pigs.

Mucosa-associated lymphoid tissue (MALT) is a specialized form of peripheral lymphoid tissue (LT), which is found on mucosal surfaces exposed to the environment. However, morphological data of these tissues in farm animals are scarce. This study investigated the gross anatomical and histological features of genital organ-associated lymphoid tissues (GOALTs) in the vaginal vestibule (VV) of healthy, non-pregnant, adult goats and pigs. Their VVs were composed of stratified squamous, non-keratinized epithelium, and various-sized dark-blue hematoxylin-positive spots were observed in whole-mount specimens, which were diffusely distributed throughout the mucosal surfaces. These spots were histologically identified as LTs and consisted of lymphatic nodules (LNs) or diffuse lymphoid tissue (DLTs). Both LNs and DLTs contained B cells, T cells, macrophages, dendritic cells, plasma cells, and high endothelial venules. Only the numbers of B cells were significantly higher in both the LNs and DLTs of pigs compared to goats. Furthermore, the surface of the VV epithelium covering the LTs was partially disrupted with a large intercellular space containing abundant connective tissue fibers with numerous lymphocytes. In conclusion, GOALTs in the VV appear to be common local immunological barriers in both examined animals. This knowledge is crucial for understanding the structures and disorders of female reproductive organs in farm animals.

Histopathological presence of dermal elements in resected margins of neural structures obtained from initial repair surgery for myelomeningocele.

Development of dermoid or epidermoid cysts in myelomeningocele (MMC) sites is generally thought to occur in a delayed fashion due to implantation of dermal elements during initial repair surgery. Another theory is that dermal and dermoid elements may already be present within dysplastic neural structures at birth. We experienced histopathological presence of dermal elements in resected tissues at initial repair surgery in four out of 18 cases with MMC who required resection of parts or margins of the neural structures to perform cord untethering. Since one of these cases has already been reported, we describe the clinicopathological findings for the remaining three cases. In Case1, cryptic dermoid elements were discovered in the terminal filum-like structure (FT-LS) caudal to the open neural placode (NP). The FT-LS had histopathological characteristics similar to the retained medullary cord. In Case 2, dermoid elements were discovered in the caudal margin of the dysplastic conus medullaris. In Case 3, a thin squamous epithelial layer overlapped the rostral margin of the NP where the NP was located near the skin. Case 1 developed an epidermoid cyst at 1 year and 2 months of age, which was totally resected. Prenatally existing cryptic dermoid elements in the caudal portion of neural structures and remnants of dermal elements overlapping the rostral margin of the NP are associated with delayed occurrence of dermoid/ epidermoid cysts. Postoperative histopathological investigation of the resected specimens is recommended. Once dermal elements are revealed, repeated imaging examination and additional surgery should be considered.

Age-dependent distribution and size of lymphatic nodules as components of extrahepatic bile duct-associated lymphatic tissue in domestic swine - a micromorphometric study

Due to the biological and immunological similarity between pigs and humans, pigs are used in medical research. Many morphological studies regarding the structure of the components of mucosal associated lymphatic tissue have been performed in animals including pigs as well as in humans. However, no any information about the existence of extrahepatic bile duct-associated lymphoid tissue (EHBDALT) is available in pigs. The aim of this work was to study the distribution and size of lymphatic nodules in the wall of extrahepatic bile ducts of immature and mature pigs in order to describe the structure of EHBDALT as component of mucosa-associated lymphoid tissue. It was found out that EHBDALT consisted of diffuse lymphatic tissue, solitary and aggregated lymphatic nodules. In 2-month-old pigs, diffuse lymphatic tissue predominated but single lymphatic nodules were found as inactive homogenous encapsulated aggregates of lymphocytes. In mature animals, diffuse lymphatic tissue, primary and secondary nodules were observed. The present micromorphometric study allowed evaluating the age-dependent distribution and size of lymphatic nodules in porcine extrahepatic bile ducts. It provides original data on the presence and age-dependent structure of bile duct MALT in domestic pigs.

Structured Reporting of Lymph Node Cytopathology using the 2020 Sydney System Guidelines-A Retrospective Study

Introduction: Fine Needle Aspiration Cytology (FNAC) is a valuable diagnostic aid for evaluation of lymph node pathology. The new Sydney System (2020) for classification and reporting of lymph node FNAC has put forth guidelines for a categorical classification using uniform terminology and morphologic criteria, a major step towards standardisation. Aim: The study was aimed to evaluate cytopathology of lymph node lesions during 2 year period by applying the proposed Sydney system and to assess the category wise Risk Of Malignancy (ROM) by comparing with histopathology diagnosis in available cases. Materials and Methods: A retrospective observational study was conducted in 2021 December, on lymph node aspirates obtained during two-year period from January 2018 till January 2020 in the department of Pathology of a tertiary care centre. FNAC of 250 lymph node aspirates were evaluated. Smears were reviewed and categorised as per the Sydney System of reporting as, L1: non diagnostic/inadequate, L2: benign, L3: atypical cells/atypical lymphoid cells of undetermined significance, L4: suspicious for malignancy, L5: malignant. The diagnostic accuracy of cytology and ROM in each category was assessed comparing with the gold standard histopathology diagnosis where available. Results: Category wise distribution of 250 cytological diagnosis of lymphadenopathy reclassified in Sydney system were L1-14 (5.60%); L2-159 (63.60%); L3-04 (1.60%); L4-05 (2%); and L5-68 (27.20%) cases. Using histopathology as gold standard available in 53 cases, the ROM in each category was found to be 0%, 3%, 66.66%, 100% and 100%, respectively. The sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV) and diagnostic accuracy of cytological diagnosis was found to be 95.65%, 96.29%, 95.65%, 96.29% and 96%, respectively. Reactive lymphadenitis in 86 (34.40%) and metastatic carcinoma in 61 (24.40%) cases were the most common benign and malignant lesions respectively. Conclusion: The Sydney system of structured reporting in lymph node cytology provides a clear-cut terminology, uniformity, and reproducibility of reports. It enhances the role of FNAC by alerting the clinician for follow-up and ancillary studies in atypical and equivocal cases. In the non diagnostic L1 category, repeat procedure or biopsy should be recommended to avoid False Negative (FN) diagnosis.

HISTOLOGICAL AND MORPHOLOGICAL CHANGES IN THE LYMPHOID STRUCTURES OF THE GASTRIC MUCOUS MEMBRANE IN WHITE RATS WITH THE ADMINISTRATION OF SODIUM GLUTAMATE.

The aim: To determine the histological and morphological changes of the lymphoid structures of the stomach in male rats under the influence of oral sodium glutamate at the rate of 15 mg/kg of body weight. Materials and methods: The scientific experiment was performed on 20 white non-linear male rats of reproductive age (4-5 months). The experimental animals were divided into two groups (10 rats in each group), which were orally received monosodium glutamate at a dose of 15 mg/kg body weight every day. We studied the effect of 2 and 4 weekly administration of monosodium glutamate at a dose of 15 mg/kg body weight, respectively, in the I and II groups of experimental animals (depending on the week of their decapitation). Rats of the control groups (n=10) were injected with a placebo for 2 and 4 weeks, namely 0.5 ml of dechlorinated tap water at room temperature. Intact control animals were also divided into two groups, 5 rats each, depending on the week of decapitation: respectively, III group - decapitation on the 2nd week of the experiment; IV group - decapitation on the 4th week of the experiment. After the experiments were completed, animals were decapitated under light ether anesthesia. According to the purpose of the study, pieces of rat stomach measuring 1.0 x 1.0 cm were taken from the front wall of the bottom of the stomach near the great curvature, cardiac and portal parts of the organ. Histological preparations were examined using a MICROmed SEO SСAN light microscope and a Vision CCD Camera. Morphometric studies were carried out according to the method of S. B. Stefanov, using grids No. 3/16. For electron microscopic examination, pieces of the stomach wall of rats were fixed in a 2.5% solution of glutaraldehyde in a 0.1 M phosphate buffer (pH 7.2-7.4) with subsequent fixation in a 2.0% solution of osmium tetroxide. After dehydration in alcohols and acetone, the material was embedded in eponaraldite. Sections were made on an LKB-8800-III ultramicrotome and studied using a JEM - 100-V microscope. To study the structural components of the lymphoid formations of the mucous membrane of different parts of the stomach of rats, semi-thin sections were made for the purpose of sharpening the blocks, which were stained with methylene blue. Results: The analysis of the obtained data of the conducted experiment indicates that the administration of monosodium glutamate in a dose of 15 mg/kg of body weight to rats already after 14 days leads to an increase in the density and size of the lymphoid structures of the GMM. The number of immunocompetent cells between the fundus of the gastric glands and the muscle plate increases in the diffuse lymphoid tissue of the gastrointestinal tract of rats in all its parts, both in the I and II groups of experimental animals. These changes are most pronounced in the cardiac and portal parts of the stomach. In both groups of experimental animals, the migration of interepithelial lymphocytes, macrophages, plasma cells, and tissue basophils to the surface epithelium increases. In both groups of experimental animals (and the II group of rats), lymphoid nodules and lymphoid pre-nodules of the gastric mucous membrane (GMM) are located between the bottom of the gastric glands and the muscular plate of the GMM. A gradual increase of medium lymphocytes in the GMM was established both in animals of I and II groups, while large lymphocytes increased in almost the same amount in experimental animals of both groups. Similar changes occur in the characteristics of the number of plasma cells, macrophages and tissue basophils in the lymphoid pre-nodules of GMM. Conclusions: Administering monosodium glutamate to rats at a dose of 15 mg/kg of body weight for 2 weeks leads to an increase in the density and size of lymphoid structures of the mucous membrane in all parts of the stomach with a predominant increase in the number of immunocompetent cells between the bottom of the gastric glands and the muscle plate. At the same time, more pronounced changes were found in the number of small lymphocytes, which tend to decrease by the 2nd week of the experiment, and vice versa - their density increases by the 4th week of monosodium glutamate administration.

Antibodies and immune-enhancing compounds: A comprehensive review

The immune system is a complex network of cells, tissues, and organs that safeguards the body against harmful environmental factors and maintains overall health. Its primary function is to mount an immune response to prevent infections and ensure the body's well-being. This defense mechanism involves the collaboration of white blood cells, the thymus gland, spleen, lymphatic glands, stem cells, proteins, and antibodies, among other components. White blood cells act as the front line of defense by identifying and eliminating pathogens. The thymus gland plays a crucial role in the development and maturation of T-cells, which are vital for adaptive immunity. The spleen filters the blood and removes old or damaged blood cells, while lymphatic glands serve as reservoirs for immune cells and filter lymph fluid. Stem cells contribute to the continuous renewal of immune cells. Proteins, including antibodies, play a critical role in identifying and neutralizing specific pathogens. Understanding the intricate workings of the immune system, along with the development of immune-enhancing compounds and antibodies, is essential for enhancing our ability to combat infections and maintain overall health.

Papillary thyroid carcinoma arising from ectopic thyroid tissue in a neck branchial cyst

A 35-year-old man presented with a right lateral neck mass for 6 years. Thyroid function test was within normal limits. Computed tomography scan of the neck was suggestive of branchial cyst, tuberculous lymphadenopathy and normal thyroid gland. Fine needle aspiration cytology of cervical lymph node was suggestive of metastatic carcinoma. Branchial cystectomy spearing the thyroid gland was undertaken. Histopathology analysis of the resected specimen confirmed it to be papillary thyroid carcinoma originating from ectopic thyroid tissue in a branchial cyst. The patient was scheduled for total thyroidectomy and neck dissection. Unfortunately, he was lost to follow-up. A brief review of the literature regarding this unusual presentation of thyroid cancer has been provided.

Evaluation of the Role of Axillary Lymph Node Fine-Needle Aspiration Cytology in Early Breast Cancer With or Without Neoadjuvant Chemotherapy.

Fine-needle aspiration cytology (FNAC) of axillary lymph nodes (AxLNs) is performed to diagnose nodal metastasis in patients with breast cancer. Although the sensitivity of ultrasound-guided FNAC for identifying AxLN metastasis is in the range of 36%-99%, whether sentinel lymph node biopsy (SLNB) should be performed for neoadjuvant chemotherapy (NAC) patients with negative FNAC results is uncertain. This study aimed to determine the role of FNAC before NAC in the evaluation and management of AxLN in early breast cancer patients. We retrospectively analyzed 3,810 clinically node-negative (a lymph node with no clinical metastasis without FNAC or radiological suspicion of metastasis with negative FNAC results) patients with breast cancer who underwent SLNB between 2008 and 2019. We compared the positivity rate of sentinel lymph nodes (SLNs) between patients who received and those who did not receive NAC with negative FNAC results or without FNAC and axillary recurrence rate in the neoadjuvant group with negative SLNB results. In the non-neoadjuvant (primary surgery) group, the positivity rate of SLNs in patients with negative FNAC results was higher than that in patients without FNAC (33.2% vs. 12.9%; p < 0.001). However, the SLN positivity rate of patients with negative FNAC results (false-negative rate for FNAC) in the neoadjuvant group was lower than that in the primary surgery group (3.0% vs. 33.2%; p < 0.001). After a median follow-up of 3 years, one axillary nodal recurrence was observed, which was a case from the neoadjuvant non-FNAC group. None of the patients in the neoadjuvant group with negative FNAC results had axillary recurrence. The false-negative rate for FNAC in the primary surgery group was high; however, SLNB was the proper axillary staging procedure for NAC patients who have clinically suspicious AxLN metastases on radiologic examination but negative FNAC results.

Evaluation of Breast, Lymph Node, and Thyroid Fine Needle Aspiration Cytology by Liquid Based Smears and Conventional Smears

Introduction: Fine needle aspiration cytology (FNAC) is a first-line investigation for palpable lumps and is a highly cost-effective and accurate investigative technique. It is a safe, simple, rapid, minimally invasive technique. Liquid-based cytology (LBC) has been used in gynecologic-cytology for over three decades. Many laboratories have adopted LBC technique for exfoliative and FNA samples. We undertook the present study to compare the advantages and disadvantages of conventional and liquid based cytology preparations. Aim of the study: To evaluate the diagnostic accuracy of LBC and Conventional smears in fine needle aspiration cytology samples from breast, lymph nodes, and thyroid tissue. Materials and methods: FNA material from accessible sites such as palpable breast lumps, thyroid, and lymph nodes were collected from 100 patients and was processed by two different methods, i.e., Conventional smears and by LBC. Various parameters on the slides were considered and compared for both the preparations. Out of 100 FNA samples, 51% were of Thyroid, 34% were of lymph node and 15% were of breast lumps. Observations and results: Adequate cellularity and better architecture was present in conventional smears than LBC preparations. Background material was less, and monolayers were better in the LBC preparations. Informative background material (i.e. Colloid, lymphoglandular bodies, etc) was more in cases of Conventional smears. The nuclear and cytoplasmic details were nearly equally good in both the preparations. Conclusion: Both these methods have their own advantages and disadvantages. Before incorporating LBC as a routine method, pathologists should familiarize themselves with all the aspects of LBC.

Salt-and-Pepper Dyspigmentation with Groove Sign in Erasmus Syndrome: A Double Jeopardy.

Salt-and-Pepper Dyspigmentation with Groove Sign in Erasmus Syndrome: A Double Jeopardy.

Reaction of regional lymph nodes of the middle ear during ultrasound lymphotropic therapy of exudative otitis media (experimental study)

The article is devoted to structural changes in the regional lymph nodes of the middle ear (superficial, facial and deep cervical lymph nodes) in experimental animals (30 male Wistar rats) when modeling exudative otitis media and after a 7-day course of local ultrasound lymphotropic therapy. The method of conducting the experiment is described. Comparative morphological and morphometric studies of lymph nodes were carried out on the 12th day from the beginning of otitis modeling and evaluated according to 19 criteria: node cut-off area, capsule area, marginal sinus, interstitial part, paracortical area, cerebral sinuses, brain cords, area number and area of primary and secondary lymphoid nodules, area of germinal centers, specific areas of the cortex and medulla oblongata, sinus system, T-dependent and B-dependent zones, cortical-cerebral index. With exudative otitis media in the regional lymph nodes of the middle ear, compared with the physiological norm, a reaction from the intra-nodular structures was observed, indicating inhibition of drainage and detoxification in the lymph catchment area, which was considered as the morphological equivalent of the insufficiency of their lymphocyte function. Regional lymphotropic therapy using low-frequency ultrasound contributed to the positive dynamics of the structural components of the lymph nodes and the normalization of most of their indicators, which is a prerequisite for the development and use of this technology in clinical practice.

THE EVALUATION OF LYMPH NODE FINE NEEDLE ASPIRATION CYTOPATHOLOGY USING THE SYDNEY SYSTEM OF REPORTING – A TEACHING INSTITUTIONAL EXPERIENCE

Background: Fine-needle cytology (FNC) is a useful diagnostic tool in the rst line evaluation of lymphadenopathy of unknown etiology. Due to a lack of standard uniform criteria and reporting systems, the use of FNC in lymph nodes is still not universally acknowledged by clinicians. Aims/objectives: To categorize the lymph node lesions according to Sydney system of reporting the lymph node aspiration cytology cases and assess the risk of malignancy (ROM) for each diagnostic category wherever applicable. Cross sectional retrospective study Study Design: Material and methods: This study was conducted by including all the lymph node aspiration cases over a period of three years. All lymph node cytology the slides were retrieved and reviewed and categorized according to Sydney system of reporting. Corresponding histopathology slides were reviewed and risk of malignancy were calculated. There were 422 lymph node Results: cytology cases. Majority of cases (323) belonged to benign/L2 group followed by L5/malignancy (92 cases), L1/ Non diagnostic (04 cases), L3/ALUS (02 cases) and one case in L4/ suspicious category. By using standardized reporting methods, one can communicate clinically Conclusion: important information in a reproducible manner while limiting interobserver variability

РОЛЬ ШВАННОВСКИХ КЛЕТОК В ПАТОЛОГИИ ЧЕРВЕОБРАЗНОГО ОТРОСТКА У ДЕТЕЙ

Objective: To compare the immunohistochemical (IHC) characteristics of appendices removed from children with acute appendicitis and chronic pain syndrome (CP) in the right lower quadrant of the abdomen (RLQA), as well as to define clinical and morphological correlations. Methods: The structure of fifty-one appendices of children aged 5-14 years who underwent appendectomy for chronic appendicitis/CP in the RLQA (24 patients, Group 1) and acute appendicitis (27 patients, Group 2) was assessed. Image analysis of histological sections stained with hematoxylin-eosin and immunohistochemically for S100 protein and proliferating cell nuclear antigen (PCNA) was performed. Results: Image analysis showed the presence of a significantly higher volume density (VD) and numerical density (ND) (p0.05) of immunoreactive cells when stained for S100 protein, as well as the ND of intramural ganglia (p0.05) against the background of minimal histological changes in the wall of the appendix in patients of Group 1 compared to Group 2. On the contrary, the ND of PCNA-immunoreactive cells was significantly higher in patients of Group 2 against the background of pronounced inflammatory changes in the appendix (p0.01). In the biopsy samples of the Group 1 patients, a significantly higher ND of the lymphoid nodule germinal centers was also noted (p0.05), while the ND of tingible body macrophages was higher in Group 2 patients (p0.001). These results demonstrate differences in neuroimmune parameters in the appendices in the two described nosologic groups and indicate the possible role of the appendiceal neural component as a prerequisite for developing CP in the RLQA in children. Keywords: Appendix, Schwann cell, S100 protein, PCNA, appendicitis, chronic abdominal syndrome.

Реакция нейроэндокринных клеток и макрофагов селезенки на развитие опухоли в толстой кишке

Introduction. High cancer incidence requires finding new ways for comprehensive studying car-cinogenesis. Therefore, it is crucial to understand immune organ cell response and cell interaction in tumor development. The aim of the research was to study Synaptophysin+-, CD68+-cells, and biogenic amines in rat spleens during tumor development in the colon during dysplasia stages and adenocarcinoma formation. Materials and methods. Spleen histological slides of 110 mature male rats were studied 1 and 4 months after 1,2-dimethylhydrazine carcinogen administration using immunohistochemical, morphometric, and luminescent histochemical methods. Results. We found imbalanced production of biogenic amines (serotonin, histamine, and catecholamines) in the spleen and, therefore, a decrease in the cellular activity of the germinal centers of the lymphoid nodules. We also observed activation of periarteriolar lymphoid sheath (PALS) and red pulp in rats with precancerous colon lesions (1 month after carcinogen administration). At the same time, there was an increase in the number of CD68+ macrophages and Synaptophysin+ cells in the red pulp. In animals with adenocarcinoma (4 months after carcinogen introduction), the level of catecholamines in the luminescent granular cells of the PALS and the functional activity of these cells increased significantly. Simultaneously, the number of macrophages decreased in all the studied spleen compartments. Amid the decreased level of all biogenic amines in the red pulp, the quantity of Synaptophysin+ cells grew even more. Conclusion. The cells of all spleen compartments react to colon carcinogenesis, with reactivity of PALS cells and the red pulp being the most pronounced. The population of spleen macrophages undergoes rapid changes: their number increases in the red pulp in animals with precancerous lesions, while it decreases in all the splenic structures of rats with adenocarcinoma. Synaptophysin+ neuroendocrine cells of the red pulp play an important role in the reaction of the spleen to tumor development, and the number of these cells rises over time. Biogenic amines participate in the interaction of spleen cells with each other and with tumor-associated cells. Keywords: spleen, biogenic amines, neuroendocrine cells, synaptophysin, carcinogenesis

Conventional ultrasound combined with contrast-enhanced ultrasound quantitative analysis for diagnosing lung cancer metastases in neck lymph nodes

Lung cancer remains one of the most common malignant tumors. Identifying cervical lymph node metastases is important to stage lung cancer, evaluate patients’ prognosis and select appropriate treatments. This study evaluated the utility of conventional ultrasound combined with contrast-enhanced ultrasound (CEUS) quantitative analysis in diagnosing lung cancer metastases in the lymph nodes of the neck. The cervical lymph nodes of 39 patients with primary lung cancer who underwent CEUS and ultrasound-guided needle biopsy were assessed. Routine type B ultrasound was used to record the morphology of the lymph nodes and the presence of lymphatic hilum structure. The Vuebox quantitative analysis software was used to collect lymph node CEUS peak enhancements (PE), rise time (RT) and fall time (FT). The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of various parameters and imaging characteristics. The cohort comprised 26 cervical lymph nodes with lung cancer metastasis and 13 cervical lymph nodes with reactive hyperplasia. Most hilum of lymph gland were absent in the metastasis group (92.30%), most lymph nodes showed a full shape (80.77%), and few were irregularly shaped (19.23%). Most hilum of lymph gland were present in the hyperplasia group (76.95%) and showed a full shape (61.54%). The PE of the metastasis group (4852.29 a.u) was significantly lower than the hyperplasia group (11,464.70 a.u), while the difference between RT and FT indicators was not significant. ROC analysis showed that combined PE of the quantitative ultrasound contrast analysis and the presence of the lymphatic phylum structure showed satisfactory diagnostic ability for detecting lung cancer lymph node metastasis in the neck (sensitivity 73.10%, specificity 76.90%, accuracy 48.73%, p = 0.004). Conventional ultrasound observation of lymph node structure combined with quantitative analysis of peak enhancement of contrast-enhanced ultrasound showed promising value for diagnosing lung cancer metastatic lymph nodes.

Pathomorphological features of acute respiratory distress syndrome in competing lung diseases: COVID-19 and sarcoidosis

The COVID-19 pandemic is a worldwide problem. The clinical spectrum of SARS-CoV-2 infection varies from asymptomatic or paucity-symptomatic forms to conditions such as pneumonia, acute respiratory distress syndrome and multiple organ failure. Objective was to describe a clinical case of SARS-CoV-2 infection in the patient with sarcoidosis and cardiovascular pathology developing acute respiratory syndrome and lung edema. Material and methods. There were analyzed accompanying medical documentation (outpatient chart, medical history), clinical and morphological histology data (description of macro- and micro-preparations) using hematoxylin and eosin staining. Results. Lung histological examination revealed signs of diffuse alveolar damage such as hyaline membranes lining and following the contours of the alveolar walls. Areas of necrosis and desquamation of the alveolar epithelium in the form of scattered cells or layers, areas of hemorrhages and hemosiderophages are detected in the alveolar walls. In the lumen of the alveoli, a sloughed epithelium with a hemorrhagic component, few multinucleated cells, macrophages, protein masses, and accumulated edematous fluid were determined. Pulmonary vessels are moderately full-blooded, surrounded by perivascular infiltrates. Signs of lung sarcoidosis were revealed. Histological examination found epithelioid cell granulomas consisting of mononuclear phagocytes and lymphocytes, without signs of necrosis. Granulomas with a proliferative component and hemorrhage sites were determined. Giant cells with cytoplasmic inclusions were detected asteroid corpuscles and Schauman corpuscles. Non-caseous granulomas consisting of clusters of epithelioid histiocytes and giant Langhans cells surrounded by lymphocytes were detected in the lymph nodes of the lung roots. HamazakiWesenberg corpuscles inside giant cells were found in the zones of peripheral sinuses of lymph nodes. In the lumen of the bronchi, there was found fully exfoliated epithelium, mucus. Granulomas are mainly observed subendothelially on the mucous membrane, without caseous necrosis. Histological examination of the cardiovascular system revealed fragmentation of some cardiomyocytes, cardiomyocyte focal hypertrophy along with moderate interstitial edema, erythrocyte sludge. Zones of small focal sclerosis were determined. The vessels of the microcirculatory bed are anemic, with hypertrophy of the walls in small arteries and arterioles. Virological examination of the sectional material in the lungs revealed SARS-CoV-2 RNA. Conclusion. Based on the data of medical documentation and the results of a post-mortem examination, it follows that the cause of death of the patient R.A., 50 years old, was a new coronavirus infection COVID-19 that resulted in bilateral total viral pneumonia. Сo-morbidity with competing diseases such as lung sarcoidosis and cardiovascular diseases aggravated the disease course, led to the development of early ARDS and affected the lethal outcome.

THE HISTOLOGICAL AND HISTOCHEMICAL STRUCTURE OF ILEUM IN THE SLENDER-BILLED GULL (Chroicocephalus genei)

This study was aimed to identify the histological and histochemical composition of the Ileum in the Slender-billed gull (Chroicocephalus genei). It was using histological stains and histological chemical techniques. The results showed that the Ileum was relatively long, so it characterized into two parts: an anterior part and a posterior part. The results showed that the mucous layer in the two parts consisted of villi that appeared conical in the anterior region and conical to a triangle in the posterior part, and the villi were more numerous and longer in the anterior part. The villi covered with a simple columnar epithelial tissue containing goblet cells in the two regions, but the goblet cells were significantly more numerous in the posterior part. The secretory units of Lieberkuhkn's crypts were more widespread and numbered in the posterior part. Clusters of lymphocytes also seemed close to the lymph nodule in the anterior part. The outer muscle layer consisting of one layer of smooth circular muscles appeared in the anterior part, while it was composed of three secondary layers in the posterior part. Histochemically, the two parts of Ileum showed different responses between them for PAS, AB, TB, BP and SB techniques. The study concluded that the histological and histochemical composition of the Ileum appeared somewhat complicated to suit the nature of the food of this bird.

Imported parasitosis as a diagnostic challenge in Primary Healthcare Clinic in the non-endemic region — a case study of schistosomiasis in English Division student

Schistosomiasis is a parasitosis, most commonly caused by Schistosoma mansoni or Schistosoma haematobium, eventually by other species from the genus Schistosoma (blood flukes). This study presents a case of schistosomiasis in an African-origin student cured in the Primary Healthcare Clinic (PHC) in Lublin, Poland. The young adult male patient from Zimbabwe, studying in Poland, presented to the PHC, due to pain in the left down quadrant of the abdomen, bloody stools, and a single episode of drooling with a blood-stained jelly-like mass, without fever. In blood tests, there was neutropenia, lymphocytosis and eosinophilia. In a colonoscopy, numerous lymphoid nodules were observed with small regions of mucosal erythema, faded vascular drawing, and delayed small contact bleeding. The patient had an elevated level of IgE (329,5 IU/mL; N &lt; 158) and minor abnormalities in the proteinogram. Abdominal CT showed calcification of intestinal walls, suggesting infection of flukes from the Schistosoma genus. The result of histopathological examination confirmed the presence of structures interpreted as parasite eggs in intestinal crypts, lamina propria and the lumen of mesenteric vessels. It is of great importance, that general medicine physicians working in schistosomiasis non-endemic regions are aware and pay attention to various risks as well as provide referrals to advanced imaging and endoscopic procedures in patients with unusual health problems. Keeping in mind, that early signs and symptoms of schistosomiasis, and results of blood tests may remain unspecific in contrast to a more complex gastrointestinal diagnostic approach, a chance of early diagnosis and successful therapeutic intervention may be facilitated.

Cyto- and histoarchitectonics of the chicken spleen in the post-vaccination period

One of the main functions of the spleen is participation in many immunological processes, protecting the body from various harmful agents. It is a secondary organ of lymphopoiesis and the only organ of immunogenesis, which provides immune control of blood and detects genetically foreign agents in it, and performs the role of a biological filter. Therefore, the Study of its histo-architectonics has theoretical and practical significance. The histostructure of the spleen of chickens has significant differences, particularly the absence of trabeculae, a small amount of connective tissue based around large vessels. The structure of the spleen of one-day-old vaccinated and non-vaccinated chickens is not formed, as there is no differentiation of the white pulp from the red pulp, which is related to the biological features of the chickens' body. According to our research, the presence of lymphoid nodules is observed for the first time in the 25-day age of the vaccinated group chickens. According to morphometric studies, it was established that their number was 2.33 ± 0.42 pcs. Comprehensive farm vaccination programs include ten vaccinations of chickens up to 100 days of age. Under the influence of multiple antigenic stimulations in the following age periods of a 50-day-old bird (after six vaccinations: twice against infectious bronchitis and infectious bursal disease, once against Marek's disease and Newcastle disease), the 75-day (after nine times vaccination), 100-day (after ten times vaccination) number and sizes of lymphoid nodules, as well as periarterial lymphoid sheaths and periellipsoid lymphoid sheaths increased concerning chickens of the control group. Our research established that the histostructure of the spleen of one-day-old chickens of the experimental and control groups is incomplete. The bird's spleen, a peripheral organ of immune protection, is formed at 25 days. However, chickens are vaccinated twice (against Marek's disease and infectious bronchitis) in the incubator when they are less than one day old, and 90% of the planned vaccinations are completed by the age of 75 days. Therefore, studying morphological changes in the spleen of birds of different ages can be an essential tool for re-evaluating preventive treatment protocols in modern poultry farming.

Ultrasonographic and cytological characterization of ultrasound-guided fine-needle aspiration cytology of cervical lymph nodes for false-negative and false-positive diagnosis.

The primary goal of this study was to examine the ultrasound and cytological characteristics of inconsistent cases (false negatives and false positives)of ultrasound-guided fine-needle aspiration cytology (US-FNAC) of cervical lymph nodes, to investigate factors influencing the diagnostic accuracy of fine-needle aspiration, and to improve diagnostic efficiency. The results of US and FNAC of cervical lymph nodes in 562 cases treated at our institution from February 2019 to June 2021 were retrospectively analyzed. FNAC cytology results were compared with the final diagnostic results (242 surgical resections/core-needle biopsy, 320 cases followed up for more than 1year), and the final diagnostic results were taken as the gold standard, and the ultrasound features and clinicopathology-related features were systematically retrospectively analyzed in cases of inconsistency. The overall diagnostic accuracy of US-FNAC for cervical lymph nodes was 94.9%, with a false-negative rate of 6.7% and a false-positive rate of 3.8%. Analyzing the cases, sampling error due to factors associated with ultrasound features, such as larger, more numerous nodes, non-solid, hypoechoic, inhomogeneous, and increased vascularity are the main causes of false-negative diagnosis, while smaller nodules, overlapping cytologic patterns, and overinterpretation by pathologists are associated with false-positive FNAC results. Proper interpretation of cytomorphologic and ultrasound features can improve diagnostic accuracy, and diagnostic misdiagnosis should be carefully observed, the identification of both features should be enhanced to reduce interpretation errors and sampling errors and to reduce the rate of misdiagnosis and missed diagnoses in fine needle aspiration of lymph nodes.