Lymphoid Follicular Hyperplasia Research Articles

P939 Ozanimod-Exposed Patients with Ulcerative Colitis Undergoing Total Colectomy Exhibit Unique Histologic Changes in Lymph Nodes

Abstract Background Ozanimod regulates lymphocyte egress from the spleen and lymph nodes into the systemic circulation. The histologic changes which occur in the lymph nodes of patients on these therapies is unknown. We describe histologic changes in lymph nodes from patients with UC who were treated with ozanimod and underwent subsequent colectomy due to treatment-refractory disease. Methods This retrospective study included patients with UC undergoing total colectomy for treatment-refractory disease who were treated with ozanimod within the 2 months prior to colectomy and a cohort of patients with UC undergoing colectomy who did not have ozanimod exposure. Histology of the lymph nodes from the mesentery of colectomy specimens were reviewed blindly by a hematophatologist (JXC) and an expert GI pathologist (CRW). Histopathological parameters were scored and demographic and clinical data were recorded. Results Of forty-five patients treated with ozanimod at our center, 6 (13%) required surgery for treatment-refractory disease. Colectomy specimen data were available for 5 patients (1 patient had surgery at an outside center). Lymph node specimens from 6 control patients with UC who had colectomy were also examined. Demographic and clinical data are summarized in Table 1. The duration of ozanimod therapy prior to surgery ranged from 6 to 24 weeks. Lymph nodes from patients treated with ozanimod had significantly greater extent of sinus dilatation than control patients (1.5 vs 0.67, p=0.022), they also had significantly more sinus histiocytosis (2.67 vs 1.67, p=0.03) (Figure 1). There was a tendency towards more Castleman-like angiotrophic hyperplasia (1.5 vs 1, p=0.34), plasma cell infiltration (1.5 vs 0.67, p=0.26) and subcortical interfollicular expansion (1.5 vs 0.83, p=0.1) in ozanimod treated patients. Patients treated with ozanimod and controls showed similar amounts of monomorphic lymphoid cells (1.3 vs 1.5, p=0.7), follicular hyperplasia (1 vs 1.1, p=0.8) and vascular proliferation (1.5 vs 1.5, p=1). Conclusion This study identifies unique histologic changes in the lymph nodes of patients with UC treated with ozanimod. These changes could be in keeping with the known mechanism of action of ozanimod and suggests that other inflammatory pathways were driving their disease activity in these patients. The significance of the changes, particularly the Castleman-like features, needs to be further investigated. Table 1: Demographic and clinical data of patients treated with ozanimod and control patients Figure 1: Representative images of lymph nodes from patients with UC treated with ozanimod and control patients showing significant sinus dilatation in patients receiving ozanimod

DP22 Cutaneous lymphoid hyperplasia: clinicopathological correlation and a therapeutic option

Abstract Cutaneous reactive lymphoid hyperplasia, also known as cutaneous pseudolymphoma, is an uncommon entity in which there are skin lesions that histologically, and sometimes clinically, mimic cutaneous lymphoma but are not, both morphologically and immunohistochemically. Correlating clinical, pathological, immunohistochemical and, occasionally, molecular findings is essential for the diagnosis (Romero-Perez D, Blanes Martinez M, Encabo-Duran B. Pseudolinfomas cutaneous. Actas Dermosifiliogr 2016; 107:640–51). Although the majority of cases can be regarded as idiopathic, certain infections and inflammatory conditions can precipitate cutaneous reactive lymphoid hyperplasia, examples of which include Borrelia infection, insect bite reactions and folliculitis (Mitteldorf, C, Kempf, W. Cutaneous pseudolymphoma – a review on the spectrum and a proposal for a new classification. J Cutan Pathol 2020; 47:76–97). The first case was an 18-year-old woman who presented with deep dermal and subcutaneous nodules for the last 5 years that started on her limbs and were slightly itchy. The nodules were firm and deep, with minimal surface changes (hyperpigmentation and adherent scale) but did not ulcerate. She also had nodules involving her buccal mucosa, inner lips and soft tissue in the nasal bridge and a couple of deep nodules on the cheeks. Pathological examination showed a dense lymphocytic infiltrate with plasma cells admixed with other inflammatory cells involving the deep dermis with an extension to the dermal/subcutaneous junction. The pathological picture was in the spectrum of deep tumid lupus/lupus panniculitis overlap and cutaneous lymphoid hyperplasia. Immunohistochemical stains showed a mixture of inflammatory cells with CD3+ and CD20+ cells. Lip mucosal biopsy showed florid reactive lymphoid follicular hyperplasia. Her condition was resistant to multiple systemic treatments. Eventually, she underwent treatment with rituximab and had satisfactory results. The second patient is an elderly female who had multiple erythematous papules, plaques and nodules on her face. Pathological examination showed a dense dermal lymphocytic infiltrate with periadnexal predilection and reactive follicles that also were highlighted by CD20, with Bcl2 and CD3+ cells around germinal centres. She was diagnosed as having cutaneous reactive lymphoid hyperplasia. Topical calcineurin inhibitors were initiated, with a good response. In conclusion, this paper highlights the term cutaneous pseudolymphoma/cutaneous reactive lymphoid hyperplasia, presenting a few cases with clinicopathological correlation and exploring some uncommon treatment options.

Thymic Parenchymal Hyperplasia

Thymic hyperplasia is a rare condition generally caused by lymphoid follicular hyperplasia associated with autoimmune disorders. True thymic parenchymal hyperplasia unassociated with lymphoid follicular hyperplasia is extremely rare and may give rise to difficulties in diagnosis. We have studied 44 patients with true thymic hyperplasia (38 females and 6 males) aged 7 months to 64 years (mean, 36 years). Eighteen patients presented with symptoms of chest discomfort or shortness of breath; in 20 patients, the lesions were discovered incidentally. Imaging studies demonstrated enlargement of the mediastinum by a mass lesion suspicious for malignancy. All patients were treated with complete surgical excision. The tumors measured from 3.5 to 24 cm (median, 10 cm; mean, 10.46 cm). Histologic examination showed lobules of thymic tissue displaying well-developed corticomedullary architecture, with scattered Hassall corpuscles separated by mature adipose tissue and bounded by a thin fibrous capsule. No cases showed evidence of lymphoid follicular hyperplasia, cytologic atypia, or confluence of the lobules. Immunohistochemical studies showed a normal pattern of distribution for keratin-positive thymic epithelial cells against a background rich in CD3/TdT/CD1a+ lymphocytes. Twenty-nine cases had an initial clinical or pathological diagnosis of thymoma or thymoma vs thymic hyperplasia. Clinical follow-up in 26 cases showed that all patients were alive and well between 5 and 15 years after diagnosis (mean, 9 years). Thymic parenchymal hyperplasia causing significant enlargement of the normal thymus that is sufficient to cause symptoms or worrisome imaging findings should be considered in the differential diagnosis of anterior mediastinal masses. The criteria for distinguishing such lesions from lymphocyte-rich thymoma are presented.

Clinicopathological and immunohistochemical characteristics of follicular gastritis (lymphoid follicular hyperplasia) in dogs

Clinicopathological and immunohistochemical characteristics of follicular gastritis (lymphoid follicular hyperplasia) in dogs

Pediatric multicentric Castleman disease; a case report

Castleman disease (CD) is a rare B-cell lymphoproliferative disorder of unknown etiology characterized by benign lymphoid follicular hyperplasia and capillary proliferation. CD can be divided histologically into four different variants: hyaline-vascular (HV), plasma-cell (PC), mixed and plasmablastic types. The unicentric CD (UCD) is localized lymphadenopathy while multicentric CD (MCD) is a systemic disorder involving cytokine-induced polyclonal lymphoproliferation and systemic inflammation due to overexpression of interleukine-6, and can be idiopathic or associated with HIV/HHV-8 infection. Surgical removal is the gold standard for patients with unicentric CD, while multicentric CD requires systemic therapy. In our presentation we wanted to show that even multicentric type of CD can be treated surgically only and that this surgical approach can be therapeutic and not mutilating at the same time. As in every rare disease, the recording of cases in rare disease registries is essential. Accumulation of the cases enables the evaluation of treatments and may provide a solid base for guidelines update.

A Case of 31-Year-Old Female With Recurrent Tonsillitis due to Poor Differentiation of Naïve T Cells to Memory T Cells

We report a case of a 31-year-old female presented with recurrent sore throat and dyspnea even after tonsillectomy and repeated adenoidectomy. Hypertrophic lingual tonsil was removed via transoral robotic surgery and was confirmed as lymphoid follicular hyperplasia by pathological examination. The analysis of the distribution and the mean fluorescence intensity of T cells after stimulation with relevant cytokines showed impaired differentiation of naïve T cells into memory T cells. As such, defective T cell immunity had made the patient susceptible to repetitive upper respiratory infection.

Lymphoid follicular hyperplasia in patients with systemic lupus erythematosus after multiple cycles of rituximab.

Rituximab is indicated in some patients with refractory systemic lupus erythematosus (SLE). Occasionally, this medication is required in chronic form to maintain control of the disease. We described two patients who developed lymphoid follicular hyperplasia (LFH) after multiple cycles of rituximab and evaluated the expression of B cell activating factor belonging to the tumor necrosis factor (TNF) family (BAFF) and its receptors [BAFF-receptor (BAFF-R) and B cell maturation antigen (BCMA)], as possible factors related to lymphoid node enlargement. Two patients with SLE completed six and nine cycles of rituximab (1 g every 2 weeks) indicated each 9 months, achieving remission for 5 and 7 years, respectively, when developed prominent lymphadenopathies. Biopsies showed LFH. Haematological neoplasms were ruled out. Immunohistochemistry showed BAFF overexpression in the follicles, and moderate expression of BAFF-R confined to the mantle zone and BCMA to the germinal centre. Belimumab B cell activating factor belonging to the TNF family (anti-BAFF therapy) was started with positive effects on the clinical condition. LFH can develop in patients with SLE who received multiple cycles of rituximab. BAFF overexpression and moderate expression of BAFF-R and BCMA in lymph nodes were seen. These findings added to the improvement with the change to belimumab could suggest that LFH after cluster of differentiation (CD20) depletion therapy may be associated with a compensatory overexpression of BAFF and its receptors.

Anti–Integrin αvβ6 Antibody as a Diagnostic Marker for Pediatric Patients With Ulcerative Colitis

Anti–Integrin αvβ6 Antibody as a Diagnostic Marker for Pediatric Patients With Ulcerative Colitis

Pathological, molecular, and serological study of small ruminant lentiviruses in Jordan.

Background and Aim:Maedi-visna is a chronic viral disease of sheep with worldwide distribution causing substantial economic losses to the small ruminant industry. Pneumonia and mastitis are the main manifestations of the disease. This study aimed to investigate the occurrence of maedi-visna virus (MVV) in sheep using histopathology and nested polymerase chain reaction (PCR) techniques and also to estimate the seroprevalence of small ruminant lentiviruses (SRLVs) in sheep and goats using commercially available enzyme-linked immunosorbent assay (ELISA).Materials and Methods:Lung tissue samples from 380 sheep were collected and fixed in 10% formalin for histopathology and molecular diagnosis of MVV. Separately, 806 serum samples were randomly collected from 633 sheep and 173 goats to detect the seroprevalence of SRLVs using ELISA.Results:The results showed that 4.7% of lung samples (n=190) were positive by both histopathology and nested PCR, 5.8% (n = 380) were positive by histopathology only (have lymphoid follicular hyperplasia), and 7.4% (n = 190) were positive by nested PCR only. Statistical analysis revealed a moderate agreement between the two tests (Kappa=0.451, n = 190). Serology results revealed that sheep and/or goats herd prevalence was 59.8% (n = 87), while individual seroprevalence in sheep (40.1%, n = 633) was significantly higher than that in the other six countries and also significantly higher than that in goats (18.5%, n = 173) (at p < 0.05).Conclusion:The moderate statistical agreement between nested PCR and histopathological diagnosis of MVV in formalin-fixed paraffin-embedded sheep lung tissue samples (Kappa=0.451, n = 190) suggests combining both tests for more sensitive MVV detection in sheep lung samples. SRLVs seropositivity in sheep was significantly higher than in goats, thus, it is of high concern and urges the inquiry into the economic impact of the disease and the financial benefit of adopting eradication measures.

Helicobacter Species and Their Association with Gastric Pathology in a Cohort of Dogs with Chronic Gastrointestinal Signs.

Simple SummaryHelicobacter spp. represent spiral-shaped Gram-negative bacteria that can live in the acidic environment of the stomach. While their association with peptic ulcers and gastric neoplasia in people has been clearly documented, their pathogenic potential in dogs is less well defined. Helicobacter pylori, the most prevalent Helicobacter infecting people, does not seem to represent a significant problem in small animals. The aims of this study were to determine the prevalence of individual gastric Helicobacter species in dogs with chronic gastrointestinal signs, their association with gastric lesions, and to compare diagnostic techniques used to detect Helicobacter infection in dogs.Prevalence of individual Helicobacter species, data evaluating their association with gastric pathology and comparison of accuracy of diagnostic techniques are limited. The aims of this study were to determine the prevalence of gastric Helicobacter species, their association with gastric pathology, and to compare diagnostic techniques. Gastric biopsies from 84 privately-owned dogs with chronic gastrointestinal signs were obtained endoscopically. Helicobacters were detected using PCR, cytology, urease test, and histopathology. PCR detected helicobacters in 71.4% of dogs. Helicobacter heilmannii sensu stricto (s.s.) was the predominant species. Mixed infection was detected in 40% of PCR positive dogs. Gastritis was diagnosed in 38.5% of Helicobacter positive and 47.4% of Helicobacter negative dogs. Mono-infection was associated with 2.4 times increased odds of having more severe inflammation compared to mixed infection. Erosions and ulcers were common endoscopic lesions. Cytology had sensitivity/specificity of 88.3/91.7%. Association between infection and lymphoid follicular hyperplasia was demonstrated.

Human macrophages and monocyte-derived dendritic cells stimulate the proliferation of endothelial cells through midkine production.

The cytokine midkine (MK) is a growth factor that is involved in different physiological processes including tissue repair, inflammation, the development of different types of cancer and the proliferation of endothelial cells. The production of MK by primary human macrophages and monocyte-derived dendritic cells (MDDCs) was never described. We investigated whether MK is produced by primary human monocytes, macrophages and MDDCs and the capacity of macrophages and MDDCs to modulate the proliferation of endothelial cells through MK production. The TLR stimulation of human monocytes, macrophages and MDDCs induced an average of ≈200-fold increase in MK mRNA and the production of an average of 78.2, 62, 179 pg/ml MK by monocytes, macrophages and MDDCs respectively (p < 0.05). MK production was supported by its detection in CD11c+ cells, CLEC4C+ cells and CD68+ cells in biopsies of human tonsils showing reactive lymphoid follicular hyperplasia. JSH-23, which selectively inhibits NF-κB activity, decreased the TLR-induced production of MK in PMBCs, macrophages and MDDCs compared to the control (p < 0.05). The inhibition of MK production by macrophages and MDDCs using anti-MK siRNA decreased the capacity of their supernatants to stimulate the proliferation of endothelial cells (p = 0.01 and 0.04 respectively). This is the first study demonstrating that the cytokine MK is produced by primary human macrophages and MDDCs upon TLR triggering, and that these cells can stimulate endothelial cell proliferation through MK production. Our results also suggest that NF-κB plays a potential role in the production of MK in macrophages and MDDCs upon TLR stimulation. The production of MK by macrophages and MDDCs and the fact that these cells can enhance the proliferation of endothelial cells by producing MK are novel immunological phenomena that have potentially important therapeutic implications.

Association of gastric lymphofollicular hyperplasia with Helicobacter-like organisms in dogs.

BackgroundThe relationships among gastric lymphoid follicular hyperplasia (GLFH), Helicobacter‐like organisms (HLOs), and clinical signs have not been established in dogs.ObjectivesTo evaluate the epidemiologic, clinical, endoscopic, and histopathologic findings associated with GLFH in dogs, and determine the association of GLFH with HLOs and the French Bulldog (FB) breed.AnimalsTwo hundred eighty‐eight dogs that underwent gastroscopy between 2013 and 2016.MethodsRetrospective, cross‐sectional study. Gastric biopsy samples were reviewed and scored for inflammation and HLOs. Dogs were divided into 3 groups: group 1 (63 FBs), group 2 (45 non‐FB brachycephalic dogs), and group 3 (180 nonbrachycephalic dogs). Variables were evaluated for their association with GLFH.ResultsUnivariate analysis determined that intact males, young age, vomiting, gastroscopic findings (discoloration, hemorrhage, and ulcers), and histopathologic findings (gastric lamina propria lymphocytic infiltration and HLO score) were associated with GLFH (P ≤ .03). In the multivariate analysis, GLFH was associated with the HLO score (odds ratio [OR] > 5 for HLO scores 1‐2 and >15 for HLO score of 3; P < .001), with vomiting (OR > 4; P = .01) but not with FB breed (P = .76) and age (P = .1). The HLO score was associated with younger age (P < .001).Conclusion and Clinical ImportanceThe HLO score was associated with a high GLFH score. Vomiting was associated with GLFH. Helicobacter‐like organisms are highly prevalent in young dogs and GLFH is indirectly associated with this factor. Clinical relevance of the identification of GLFH and HLO remains to be determined.

Rates of colorectal cancer/polyps detection in luminal investigations post appendicectomy in patients over 40 years

Background: Acute Appendicitis is the most frequent indication for emergency abdominal surgeries worldwide. It occurs most frequently in the 2nd and 3rd decades of life, being more common in patients between 10-19 years. Luminal obstruction is the primary aetiology with lymphoid follicular hyperplasia the most common cause in the young while faecoliths, fibrosis and neoplasia are seen in older patients. Studies have shown a relationship between patients above 40 years whom present with acute appendicitis having underlying colonic cancers most especially caecal cancers with increasing age seen as a significant risk factor.

Histopathological Lesions Accompanied with First-Time Isolation of a PRRSV-2 Strain in Greece.

Genotype 2 strains of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV-2) have been reported sporadically in Europe. Even if, PRRSV-2 reported to be genetically homogenous in Europe due to the introduction of an MLV vaccine strain, independent introductions of PRRSV-2 field strains have been reported. The aim of the present study was to report the complete genome sequence and evaluate the histopathological lesions of a PRRSV-2 strain, isolated for the first time in Greece. During a routine blood sampling in a commercial pig farm, the results revealed positive samples in weaners of 40-60 days for the PRRSV-2, using real-time polymerase chain reaction. The clinical picture was characterized from respiratory symptoms in weaners, as well as coughing and poor performance at finishing stage and less than 3% mortality rate from weaning stage to finishing stage. The use of ORF5 for PRRSV phylogenetic analysis of the isolated PRRSV strain, named "x1544-1 strain", was successfully determined, belonging to the genotype PRRSV-2. Comparison of the obtained sequence revealed nucleotide sequence identity >98% with PRRSV-2 strain VR2332 and other related strains from Denmark and China. The histopathological evaluation revealed diffuse interstitial pneumonia, multifocal interstitial nephritis, while in the lymphoid organs, follicular and paracortical hyperplasia, coexisting with necrosis and depletion of germ cells were detected. The results of current study undersign the importance for veterinary practitioners to have up-to-date access to phylogenetic data linked to phenotypic information to follow-up the control and prevention strategies against PRRSV.

Hyaline vascular variant of unicentric Castleman disease of the tonsil: a case report

BackgroundCastleman disease (CD) is a lymphoproliferative disorder with an unknown etiology. The disease may be unicentric (UCD) or multicentric (MCD), and three histopathologic variants have been described: hyaline vascular (HV), plasma cell (PC), and mixed type. Extranodal CD is rare. Herein, we report a case of CD presenting as a tonsillar mass, which has not been documented in the literature.Case presentationThe patient was a 32-year-old man. Laryngoscopy revealed tonsillar hypertrophy, and the patient underwent a low-temperature plasma tonsillectomy. Microscopic examination of permanent sections showed lymphoid follicular hyperplasia, a portion of which appeared to be a fusion of nodular hyperplasia (composed of lymphoid follicles of variable size and shape). These distinctive follicles with atrophic hyalinized germinal centers and a broad mantle zone of small lymphocytes formed concentric rings (so-called onion-skin arrangement). Medium-sized vessels and a plethora of capillaries were present in the center of the lymphatic follicles, mantle zones, and interfollicular areas. A characteristic lollipop appearance was also observed due to the onion-skin arrangement of the expanded mantle zone lymphocytes with a vessel penetrating the germinal center. No aberrant lymphoid population was present based on CD3, CD5, CD20, CD79α, CD21, CD23, bcl-2, cyclin D1, and ki-67 immunostaining. Tests for human herpesvirus (HHV)-8 and Epstein Barr virus (EBV)-encoded small RNA (EBER) were negative. Therefore, a diagnosis of an HV variant UCD was rendered. The patient was treated by local excision without any other therapy based on the diagnosis. At the 7-month follow up, the patient had no recurrent symptoms or masses.ConclusionWe present an unusual case of a tonsil presenting hyaline vascular Castleman disease (HVCD). This study aims to highlight CD as a differential diagnosis that should be considered by otolaryngologists and pathologists for lymphoproliferative disorders of the tonsil.

Comparative study of computed tomography of normal and lymphoid follicular hyperplasia thymus in myasthenia gravis patients.

The aim of the present study was to evaluate the thymuses of non-thymomatous myasthenia gravis (MG) patients by computed tomography (CT) for differentiating lymphoid follicular hyperplasia (LFH) thymus from normal/involuted thymus in order to assist surgeons in determining whether a non-thymomatous MG patient requires an operation. In the present retrospective review over 10 years, 80 patients who received CT scan and thymectomy at the Affiliated General Hospital of Tianjin Medial University (Tianjin, China) were included. According to the pathological records, 54 of the cases initially detected on CT were confirmed as LFH thymus. Thymic measurements, including anteroposterior and transverse dimensions, width (the longest axis of the lobe on a transverse scan) and thickness (the largest dimension perpendicular to the long axis of the lobe) and CT attenuation of the thymus region, adipose tissue and chest wall musculature in each CT slice were included to assess differences between the LFH group and the normal/involuted thymus group. Although a negative association between patient age and the CT attenuation of the thymus region was identified (r=-0.779, P<0.05, Pearson's correlation test), the LFH thymus group featured nodular changes on CT, while no such changes were observed in the normal/involuted thymus group. The mean age of disease onset in the LFH thymus group was significantly lower than that in the normal thymus group (40.2±17.3 vs. 59.2±9.3 years). Furthermore, significant differences in CT attenuation were identified between the LFH group and the normal/involuted thymus group [-41.21±54.42 vs. -108.23±8.72 Hounsfield units (HU) on unenhanced CT; -25.57±58.65 vs.-117.40±6.22 HU on contrast-enhanced CT]. In the LFH group, the difference in mean CT attenuation between the thymus region and adipose tissue was significant, while no significant difference was observed in the normal/involuted thymus group. In conclusion, CT may be used to distinguish LFH thymus from normal/involuted thymus in MG patients.

Chronic Lymphocytic Leukemia Manifesting as Colon Polyps

Chronic lymphocytic leukemia (CLL) is a chronic lymphoproliferative disorder and the most common leukemia in the U.S. representing 30% of all leukemias. CLL is a disease of the elderly; mean age of 70 at diagnosis and often asymptomatic. Lymphadenopathy, splenomegaly, and hepatomegaly are common findings. CLL cells can infiltrate any organ but gastrointestinal mucosal involvement is rare. A 54 y/o African-American male presented for screening colonoscopy. Initially diagnosed with CLL in 2014 with bulky lymphadenopathy, night sweats, and weight loss. Lymph node biopsy confirmed the diagnosis showing Trisomy 12, ZAP 70 positive, and CD 38 positive. Initial treatment consisted of Bendamustine and Rituximab. Prior to colonoscopy the patient had stable lymphadenopathy but denied B symptoms and recent labs were within normal limits including LDH and CBC. Colonoscopy was poor prep and from the proximal ascending colon to distal descending colon were multiple small polyps measuring 3-4 mm in size with an appearance similar to either hyperplastic polyps versus lymphoid follicular hyperplasia. In total there were greater than 40 polyps seen. Due to these findings random polypectomies were performed. Histologic examination showed atypical submucosal lymphoid cells. Immunohistochemical staining showed diffusely positive CD5, CD20, CD79a and BCL2 staining. CD10, BCL6, and Cyclin D1 were negative; consistent with a diagnosis of CD5+ low grade lymphoma. The patient was referred to the oncology department for evaluation. The patient was noted to have no B symptoms. He did have an elevated WBC count at 19,000 with increased lymphocytes but with normal hemoglobin and platelet count. The patient's LDH was mildly elevated and subsequently he underwent PET-CT scan which showed some mildly hypermetabolic bilateral axillary lymph nodes but otherwise normal. Recommendation was routine monitoring given lack of cytopenias, B symptoms, or evidence of transformation. Diagnosis of CLL is based on strict criteria including absolute B lymphocyte count >5,000/micoL [5 x 109/L] with mature-appearing small lymphocytes with clonality. Treatment of CLL is based on disease activity judged by B symptoms, progressive increase in lymphadenopathy, pain, or the presence of symptomatic cytopenias, hemolytic anemia, progressive disease, or repeated infections. Gastroenterologists need to keep CLL on the differential when performing endoscopy on patients who have diffuse polyposis.

Immunohistochemical Detection of Porcine Reproductive and Respiratory Syndrome Virus Antigen in Formalin-Fixed, Paraffin-Embedded Tissues with Correlation to Clinicopathologic Data

Immunohistochemistry (IHC) was used in this study to detect the presence of porcine reproductive and respiratory virus (PRRSV) antigen using monoclonal antibody (Mab SDOW17) in formalin-fixed, paraffin embedded tissues of lung, lymph node, heart, spleen, and kidney of pre- weaning to less than 90 day old pigs. Out of the 25 tissue samples examined from swine cases of the Philippine Animal Health Center (PAHC), Bureau of Animal Industry and College of Veterinary Medicine (CVM) Histopathology Laboratory, University of the Philippines-Los Baños (UPLB), 14 or 56% (14/25) were IHC positive for PRRSV antigen. Among the selected tissue samples, the PRRS virus was detected the most in the lymph nodes (64%) and lungs (40%), respectively, compared to other organs such as spleen (33%), kidney (28%), and the heart (17%). Only 43% (6/14) of cases coincided with the pathogenesis and clinicopathologic lesions of PRRS which are proliferative interstitial pneumonia and lymphoid follicular hyperplasia and necrosis. PRRS positive cases in IHC were consistently found to have co-infections with viral and bacterial diseases. Since PRRSV has tropism for macrophages and destruction of these cells leads to immunosuppression, affected animals are vulnerable to secondary infections. Keywords: formalin-fixed; immunohistochemistry; paraffin embedded tissue; piglets; Porcine Reproductive and Respiratory Syndrome; PRRS virus antigen; Mab SDOW17

Gastric Histopathology of Chronic Gastritis in Obese Patients Undergoing Laparoscopic Sleeve Gastrectomy: A Local Experience

A retrospective review was conducted using the database at King Abdulaziz University Hospital, to determine the most common cause of chronic gastritis among obese individuals. One hundred and thirty-one specimens were examined, obtained from patients who had laparoscopic sleeve gastrectomy and diagnosed with chronic gastritis. Helicobacter pylori was detected in 15 cases only. The most common diagnosis was “Chronic inactive gastritis without Helicobacter pylori infection” in 57 (43.50%) cases, then “Chronic gastritis with lymphoid follicular hyperplasia” in 54 (41.20%) cases, and lastly “Chronic active gastritis” in the remaining 20 (15.20%) Cases. The low incidence of Helicobacter pylori infection even in cases of gastritis with lymphoid follicular hyperplasia support the existence of the new proposed entity (i.e., obesity-related gastritis). Biopsy specimens for cases diagnosed as chronic gastritis were used as control group to confirm the appropriate rate of detecting Helicobacter pylori organisms by morphological examination in the same laboratory. In these biopsies, Helicobacter pylori was present in (50.70%), and reactive follicular hyperplasia was detected in (6%) of total controls.

State of regional lymph nodes and prognosis in stomach cancer

Aim. Multiparameter analysis of the state of regional lymph nodes of stomach cancer to reveal prognostic criteria of patients’ 5-year survival. &#x0D; Methods. The regional lymph nodes removed during surgery for stomach cancer in 170 oncologic patients were studied by means of histologic, immunohistochemical, electron microscopy and morphometric methods. The 5-year survival was calculated by the direct method. &#x0D; Results. It was revealed that 5-year survival directly depends on the amount of involved lymph nodes. Detection of even single tumor cells in one regional lymph node worsens the prognosis for a patient’s life. The more metastases there are in lymph tissue, the worse the prognosis is. Immunomorphologic reactions and ultrastructural changes are of substantial significance. High 5-year survival was characteristic for hyperplasia of paracortical area with increased number of CD3(+) T-cells, the ultrastructure of which corresponds to activated (immune) lymphocytes, and for sinus histiocytosis as well with increased number of CD68(+) free macrophages in regional lymph nodes with pronounced phagocytic activity. Prognosis is worse in lymphoid follicular hyperplasia with high content of CD20(+) B-cells and plasmocytes. The lowest 5-year survival was accompanied by degenerative sinus histiocytosis, atrophy or sclerolipomatosis transformation of lymphoid tissue with hypoplasia of paracortical area and lymphoid follicles. Under an electron microscope active fibroblasts are seen synthesizing collagen and large number of degenerating cell forms, particularly, lymphocytes. &#x0D; Conclusion. The 5-year survival of oncologic patients with stomach cancer is determined by the amount of metastatic regional lymph nodes, presence or absence of metastases, their volume in lymphoid tissue, histologic pattern and ultrastructural cell changes; comparative analysis of these criteria allows developing prognostic algorithm.