White Nodules Research Articles

Delayed Sympathetic Ophthalmia Involving Posterior Segment a Dilemma: A Case Report

We report a case of 11 year old young girl referred with complaint of right sided photophobia and pain following faucet induced trauma to left eye 3 months ago, followed by loss of sight in left eye. Patient presented to us with prepthisical left eye and anterior segment uveitis in right eye. Fundus picture revealed cream colour white nodules confirmed as Dalen Fuchs on fundus fluorescein angiography and presence of hypereflective lesions placed at level of retinal pigment epithelium with disruption of the inner and outer segment (IS/OS) junction on spectral domain optical coherence tomography. Ultrasonogram-B-scan confirmed closed funnel retinal detachment in traumatized left eye and increased choroidal thickness in sympathizing right eye. She underwent orbital computerized axial tomography scan to rule out intraocular foreign body. She was diagnosed as a case of delayed sympathetic ophthalmia. Subsequently she was put on intensive topical with oral steroids and immunesuppressive therapy constituted with oral azathioprine and methotrexate continued for one year and tapered on resolution of presenting signs. At final follow up sympathizing eye was quiescent and sympathetic eye was prepthisical. Sympathetic ophthalmia needs to be distinguished from other ocular auto-immune disorder such as Vogt Koyanagi Harada disease and Acute Multifocal Pigment Placoid Epitheliopathy to which it bears striking resemblance. As these disorders have variable response to treatment with widely differing outcome one must keep that in view while managing them. It is important to remember as the treatment is prolonged recurrences and patient drop outs are commonly noted.

Prevalence and antibiotic resistance of Aeromonas schubertii causing internal white spot disease on snakehead fish, Channa striata, in the Mekong Delta, Vietnam

AbstractSnakehead, Channa striata, has a long history of invasion and associated negative impacts on the biodiversity of native aquatic organisms in the Mekong Delta. However, internal white spot disease caused by Aeromonas schubertii has a massive effect on the production of snakehead fish but also can spread to wild populations and to consumers. The aim of the study was to investigate the prevalence of multi‐antibiotic resistance (MAR) of A. schubertii isolated from snakehead fish cultured in several Mekong Delta fish farms, as well as its potential to spread throughout the infection season. Based on morphological and biochemical tests, as well as phylogenetic analysis of three housekeeping genes (16S rRNA, gyrB, and rpoD), isolates recovered from white nodules were strongly identified as A. schubertii. The antibiotic susceptibility testing revealed that all of the isolates (n = 25) were phenotypically multidrug‐resistant, with resistance to erythromycin (84%), rifampicin (84%), flumequine (88%), amoxicillin (96%), ciprofloxacin (92%), and florfenicol (92%). The multiple antibiotic resistance indices ranged from 0.33 to 0.92, with A. schubertii isolate As28 being resistant against 11 out of the 12 tested antibiotics. In particular, 15 MAR phenotypes (MARPs) were found in 25 isolates with 8 isolates (32%) commonly displaying MAR phenotypes against patterns of Ery–Rif–Flq–Aml–Cip–Flo, and four isolates (16%) expressing patterns of Ery–Rif–Nov–Flq–Aml–Cip–Flo. A hierarchical clustering analysis of their antibiotic‐resistant bacteria may indicate cross‐invasion between ponds/fish farms and its ability to survive in aquatic environments for long periods (at least 3 months). Our results suggest that the diversity of MARPs bacteria in snakehead represents a potential hazard to modifying the composition of native aquatic organisms, especially to consumers. To successfully manage C. striata in the future, several eco‐friendly techniques should be used to restrict the spread of A. schubertii inside the invaded habitat of the Mekong Delta river.

A New Parasitic Archamoeba Causing Systemic Granulomatous Disease in Goldfish Extends the Diversity of Pathogenic Endolimax spp.

Endolimax is a genus of intestinal amoebae which stands among the least known human protists. Previous studies on amoebic systemic granulomatosis of a marine fish (Solea senegalensis) resulted in the unexpected characterization of a new organism which was related to Endolimax and named E. piscium. The existence of multiple reports of systemic granulomatosis caused presumptively by unidentified amoebae in goldfish lead us to investigate the organism involved in goldfish disease. Analysed goldfish presented small whitish nodules in the kidney, which correspond to chronic granulomatous inflammatory reactions with a ring-layer of amoebae in the periphery. Amoebae were amitochondriate and were located in a parasitophorous vacuole within macrophages, as previous studies on this condition in goldfish and other freshwater fish pointed out. SSU rDNA characterization confirmed a new Endolimax lineage which appears closely related to E. piscium, but the molecular evidence, distinct pathological features and lack of ecological overlapping between the hosts support their assignment to a new species, E. carassius. The results support the existence of a considerable unexplored diversity of Endolimax spp. among fish, and their proper characterization can contribute to an understanding of Archamoebae evolution and pathogenic potential.

Concurrent infections of Streptococcus iniae and Aeromonas veronii in farmed Giant snakehead (Channa micropeltes).

The giant snakehead, Channa micropeltes, is an increasingly important economic freshwater fish in Thailand and other regions of Asia. Presently, giant snakehead are cultured under intensive aquaculture conditions, leading to high stress and conditions favouring disease. In this study, we reported a disease outbreak in farmed giant snakehead with a cumulative mortality of 52.5%, continuing for 2 months. The affected fish exhibited signs of lethargy, anorexia and haemorrhage of the skin and eyes. Further bacterial isolations revealed two different types of colonies on tryptic soy agar: small white, punctate colonies of gram-positive cocci and cream-coloured, round and convex colonies of rod-shaped gram-negative bacteria. Additional biochemical and species-specific PCR analysis based on 16S rRNA confirmed the isolates as Streptococcus iniae and Aeromonas veronii. Multilocus sequence analysis (MLSA) placed the S.iniae isolate into a large clade of strains from clinically infected fish worldwide. Gross necropsy findings showed liver congestion, pericarditis and white nodules in the kidney and liver. Histologically, the affected fish showed focal to multifocal granulomas with inflammatory cell infiltration in kidney and liver, enlarged blood vessels with mild congestion within the meninges of the brain and severe necrotizing and suppurative pericarditis with myocardial infarction. Antibiotic susceptibility tests revealed that S.iniae was sensitive to amoxicillin, erythromycin, enrofloxacin, oxytetracycline, doxycycline and resistant to sulfamethoxazole-trimethoprim, while the A.veronii was susceptible to erythromycin, enrofloxacin, oxytetracycline, doxycycline, sulfamethoxazole-trimethoprim and resistant to amoxicillin. Conclusively, our findings highlighted the natural concurrent bacterial infections in cultured giant snakehead, which support the implementation of appropriate treatment and control strategies.

Automatic recognition of lung tumor using convolutional neural networks

The unchecked proliferation of abnormal cells in the lung is known as lung cancer, and it is one of the major causes of death globally. The most accurate way for finding malignant lung nodules is a thorax Computed Tomography (CT) scan. A spherical lesion called a lung nodule can either be malignant or not. Lung cancer appears as rounded, white shadow nodules on the CT scan. The candidate ROIs are calculated using existing method and some blood vessels are removed using rule-based methods based on the candidate ROIs' shape features. Next, the candidate ROIs' remaining grey and texture features are calculated, and are given to the classifier to categorize the candidates. The rule-based technique has no omissions, according to experimental results, however the misclassification probability is too high. Therefore, in the proposed method, by computing the texture features from the Grey Level Co-occurrence Matrix (GLCM) in the wavelet domain, the nodules were identified and CT images were categorized using Convolutional Neural Networks (CNN) into two groups: those with and those without malignant lung nodules. In this work, two classifiers Support Vector Machine (SVM) and CNN are used for the recognized lung cancer image to determine the severity of the condition. Comparisons between SVM and CNN classifiers are done with regard to quality parameters including accuracy and sensitivity.

Primary duodenal carcinoma suspected to arise from ectopic gastric mucosa: a case report

BackgroundEctopic gastric mucosa mainly occurs in the duodenal bulb, and its etiology is thought to be congenital straying of gastric tissues. Primary duodenal carcinoma is a rare disease; however, reports of carcinoma arising from ectopic gastric mucosa are extremely rare. We report a case of primary duodenal carcinoma suspected to arise from ectopic gastric mucosa, which discovered as a result of duodenal stenosis.Case presentationThe patient was a 71-year-old man with persistent weight loss and white stools. Enhanced computed tomography showed stenosis of the third portion of the duodenum and main pancreatic duct dilatation. Upper gastrointestinal endoscopy revealed irregularity of the duodenal mucosa from the anorectal side of the papilla of Vater to the stenosis of the third portion. No malignant cells were found by biopsies from the duodenal mucosa. Endoscopic ultrasonography did not detect the tumor in the pancreatic head. The possibility of a pancreatic tumor could not be ruled out based on findings of main pancreatic duct dilatation in the pancreatic head, and the patient had long-term poor oral intake because of duodenal stenosis; thus, surgical treatment was planned. Intraoperative findings showed palpable induration of the third portion of the duodenum and white nodules on the serosal surface. This was diagnosed as primary duodenal carcinoma, and pylorus-preserving pancreatoduodenectomy was performed. Histopathological diagnosis revealed ectopic gastric mucosa in the papilla of Vater and well-differentiated tubular adenocarcinoma invaded the normal duodenal submucosa and extended to the duodenal serosa. No mass lesion was detected in the pancreas, and an intraductal papillary mucinous neoplasm was observed in the branch pancreatic duct. The main pancreatic duct stricture was caused by the duodenal carcinoma invasion.ConclusionsThis case of primary duodenal carcinoma was suspected to arise from ectopic gastric mucosa and review the relevant literature.

Mucosal Schwann cell hamartoma: a benign and little-known entity.

Dear editor, 50 years-old female with personal history of mutation of the gene BRCA1 and previous prophylactic double anexectomy consulted for rectal bleeding without pain since two weeks. A blood test was performed, with hemoglobin levels of 13.1g/dl and without iron deficiency. In the anal inspection there were neither external hemorrhoids nor anal fistulas, so a colonoscopy was requested. In the colonoscopy, all the colon mucosa was normal but, in the rectal retroflexion, apart from internal engorged hemorrhoids, surrounding the 50% of the anal opening an erythematous and indurated mucosa was found (figure 1). Biopsies were taken. The pathology report informed of proliferation of spindle-shaped cells exclusively in the lamina propria with eosinophilic cytoplasm and unclear cell borders (figure 2). Not nuclear atypia or mitotic activity were observed. On immunohistochemistry, S-100 protein was strongly positive (figure 3) and CD34, SMA, EMA and c-kit were negative. These results are concordant with the diagnosis of Schwann cells in the context of a mucosal Schwann cell hamartoma (MSCH). Given that these lesions seem to not have malignant potential, the patient was discharged without control colonoscopies. The episodes of rectorrhagia were attributed to the presence of internal hemorrhoids. Discussion: MSCH are benign and intramucosal tumors with a mesenchymal origin. They are most commonly located in the distal colon, but they were also found in the gallbladder, the esophagogastric union and in the antrum. They are observed most frequently in middle aged women (around 60 years-old) and they are generally asymptomatic. They are presented as polyps between 1 and 6mm, but in other cases they appeared as small whitish nodules, protruding lesions with normal superficial mucosa or even they were found in random biopsies of the colon. The MSCH are a rare entity with an unknown prevalence. Less than 100 cases are described in the literature. It is essential the differentiation between this entity and the Schwanomas or the gastrointestinal stromal tumors (GIST). Schwanomas are rare in the colon, they are well circumscribed (in contrast with the MSCH) and they are not limited to the lamina propria. GIST are more frequently located in the stomach and they are positive for c-kit. MSCH are not associated with hereditary syndromes such as neurofibromatosis and, in contrast with Schwanomas or GIST, they do not require surveillance because they are benign.

Outbreak of Marek’s Disease in Chicken Flocks with Uncommon Pattern of Gross Lesions

Marek’s disease is one of the highly contagious and oncogenic diseases of poultry that remains as a threat to the fast-growing poultry sector, even after proper vaccination. Generally, the disease is identified incidentally during the routine postmortem examination as nerve enlargement or as gross tumor lesions. The present article discusses the outbreak of Marek’s disease in three vaccinated commercial layer flocks with high mortality and subtle gross nodular lesions. Three to fivemonth- old, commercial layer chickens from three different farms were submitted for post mortem at Department of Veterinary Pathology, College of Veterinary and Animal Sciences, Pookode, Kerala with the history of weight loss and mortality rate of about 25 per cent. On postmortem examination, the carcasses revealed severe emaciation and atrophied to mildly enlarged visceral organs in the majority of cases except in three birds with small white nodules. Microscopical examination revealed, varying degrees of pleomorphic lymphoid cell proliferation in the liver, spleen, kidney, ovary, pancreas and thyroid. Polymerase chain reaction targeting gB gene confirmed the presence of Marek’s disease virus (MDV) in birds, with and without gross tumors. The birds from farms of different flock size showed similar high mortality rate but mostly without gross tumour lesions of MD. These findings emphasise the importance of histopathological examination in routine postmortem of chickens to identify diseases with gross nonspecific lesions.

FlgC gene is involved in the virulence regulation of Pseudomonas plecoglossicida and affects the immune response of Epinephelus coioides

As a pathogen of cultured teleosts, Pseudomonas plecoglossicida has caused significant economic losses. flgC plays an important role in encoding flagellar basal-body rod proteins. Our previous studies revealed the high expression of P. plecoglossicida flgC in infected Epinephelus coioides. To explore the role of flgC in the virulence of P. plecoglossicida and the immune response of E. coioides to the infection of P. plecoglossicida, flgC gene of P. plecoglossicida was knocked down by RNA interference (RNAi). The results showed that the flgC gene in all four mutants of P. plecoglossicida was significantly knocked down, and the mutant with the best knockdown efficiency of 94.3% was selected for subsequent studies. Compared with the NZBD9 strain of P. plecoglossicida, the flgC-RNAi strain showed a significantly decrease in chemotaxis, motility, adhesion, and biofilm formation. Furthermore, compared with the E. coioides infected with the NZBD9 strain, the infection of flgC-RNAi strain resulted in the infected E. coioides a 1.5-day delay in the time of first death and an 80% increase in survival rate, far fewer white nodules upon the spleen surfaces, and lower pathogen load in the spleens. RNAi of flgC significantly influenced the metabolome and transcriptome of the spleen in infected E. coioides. KEGG enrichment analysis exhibited that the Toll-like receptor signaling pathway was the most enriched immune pathway; the most significantly enriched metabolic pathways were associated with Linoleic acid metabolism, Choline metabolism in cancer, and Glycerophospholipid metabolism. Further combined analysis of transcriptome and metabolome indicated significant correlations among pantothenate and CoA biosynthesis, beta-alanine metabolism, lysosome metabolites, and related genes. These results suggested that flgC was a pathogenic gene of P. plecoglossicida; flgC was associated with the regulation of chemotaxis, motility, biofilm formation, and adhesion; flgC influenced the immune response of E. coioides to the infection of P. plecoglossicida.

A synthetic peptide based on large yellow croaker (Larimichthys crocea) IFNG1R protein sequence has potential antimicrobial activity against Pseudomonas plecoglossicida

The overuse of antibiotics leads to the emergence of bacterial resistance, which poses a serious threat to aquaculture. Antimicrobial peptides (AMPs) display excellent antimicrobial activity and are thought to be the most feasible replacements for antibiotics. The usage of AMPs as feed additives has great application prospects in aquaculture. In this study, large yellow croaker interferon-γ related gene (IFNG1R) was cloned, and a 17-amino acids (aa) short peptide named SKL17-2 was synthesized based on its protein sequence. The synthesized SKL17-2 peptide possessed a strong antimicrobial activity against Pseudomonas plecoglossicida, which could cause visceral white nodules disease (VWND) in cultured marine fish, with a minimum inhibitory concentration (MIC) of 2 μM. SKL17-2 peptide also showed weak antimicrobial activities against other tested bacteria, indicating its narrow-spectrum antimicrobial activity. This suggested that SKL17-2 peptide may not kill probiotics in intestinal flora when used as the feed additive. Furthermore, SKL17-2 had broad temperature and pH stability, low cytotoxicity, and negligible hemolysis, indicating its good biosafety and stability. Mechanistically, the synthesized SKL17-2 peptide can form α-helical structure in a membrane environment and destroy P. plecoglossicida through membrane disruption. Thus, our data showed that SKL17-2 peptide may represent a potential feed additive used for prevention and treatment of VWND.

Comparative Transcriptomics Reveals the microRNA-Mediated Immune Response of Large Yellow Croaker (Larimichthys crocea) to Pseudomonas plecoglossicida Infection

Visceral white nodules disease (VWND), caused by Pseudomonas plecoglossicida, is a common disease among cage-farmed large yellow croaker (Larimichthys crocea) in China. However, comprehensive investigations of the molecular defensive mechanisms used by L. crocea in response to P. plecoglossicida infection remain relatively rare. Here, we constructed transcriptomes of the L. crocea spleen at 12 h and 24 h after P. plecoglossicida challenge. We identified 518 novel miRNAs and 823 known miRNAs in the spleen of L. crocea. Between the challenge and control groups, 32 differentially expressed miRNAs (DEmiRNAs), predicted to target 356 genes, and 1152 differentially expressed mRNAs (DEmRNAs) were identified at 12 h post-infection, while 33 DEmiRNAs, predicted to target 278 genes, and 1067 DEmRNAs were identified at 24 h post-infection. Gene ontology (GO) analysis showed that 146 and 126 GO terms were significantly enriched in the target genes at 12 h and 24 h, respectively. Twenty-eight and four immune-associated Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were significantly enriched in the target genes at 12 h and 24 h, respectively. Three immune-associated pathways were among those most enriched in the target genes: Toll-like receptor signaling, endocytosis, and C-type lectin receptor signaling. Network analysis identified 47 DEmRNA-DEmiRNA pairs. In particular, the immune-related genes TLR5S and PIGR were targeted by the miRNAs lcr-miR-7132c and dre-miR-183-5p, respectively. Dual-luciferase assays verified that lcr-miR-7132c downregulated TLR5S, suggesting that this miRNA may participate in regulating the immune response of L. crocea to P. plecoglossicida infection through the TLR5S-mediated signaling pathway. Our results help to clarify the miRNA-mediated immune response of L. crocea to P. plecoglossicida infection.

Clinical and Pathological Findings Associated with Mycobacteriosis in Captive Syngnathids

Mycobacteriosis is an important disease that affects captive and wild aquatic fish. Syngnathids are susceptible to infection by non-tuberculous mycobacteria. The aim of this study was to describe clinical signs, and macroscopic and histological lesions in 25 syngnathids and the molecular characterization of the causative mycobacteria. Clinical presentation ranged from sudden death to non-specific signs, including anorexia, poor body condition, weight loss and marked dyspnea with increased respiratory effort and rate. Gross lesions were mostly ulcers on the tail and small white nodules in the liver, coelomic cavity and inside the eye. The most affected organs were gills, liver, intestine and coelomic mesentery. Microscopic lesions consisted of areas of multifocal to diffuse granulomatous inflammation and bacterial emboli with numerous intralesional acid-fast bacilli. Epithelioid cells, multinucleated giant cells, lymphocytes and fibrous connective tissue, which are commonly observed in granulomatous inflammation, were not observed here. In the real-time PCR, M. fortuitum, M. chelonae and M. marinum common primers, Mycobacterium spp. were detected in 4, 7 and 14 individuals, respectively. In addition, this is the first description of mycobacteriosis found in Syngnathus acus.

Evaluation of the Protective Immune Response Induced by an rfbG-Deficient Salmonella enterica Serovar Enteritidis Strain as a Live Attenuated DIVA (Differentiation of Infected and Vaccinated Animals) Vaccine in Chickens.

Salmonella enterica serovar Enteritidis (S. Enteritidis), one of the zoonotic pathogens, not only results in significant financial losses for the global poultry industry but also has the potential to spread to humans through poultry and poultry products. Vaccination is an effective method to prevent Salmonella infections. In this study, we constructed a live attenuated DIVA (differentiation of infected and vaccinated animals) vaccine candidate, Z11ΔrfbG, and evaluated its protective effectiveness and DIVA potential in chickens. Compared to that of the virulent wild-type strain, the 50% lethal dose (LD50) of the rfbG mutant strain increased 56-fold, confirming its attenuation. High serum levels of S. Enteritidis-specific IgG titers indicated that a significant humoral immune response was induced in the vaccinated group. After challenge, the nonvaccinated group showed serious clinical symptoms (diarrhea, depression, decreased appetite, ruffled feathers, and weight loss), pathological changes (white nodules in the liver and fatty lesions in liver cells), and death. In contrast, there were no clinical symptoms, pathological changes, or death in the 5 × 106- and 5 × 107-CFU-vaccinated groups. Z11ΔrfbG vaccination significantly reduced S. Enteritidis colonization in the spleen, liver, and cecum. In addition, the Z11ΔrfbG-vaccinated group exhibited a negative response to the serological test, whereas the virulent wild-type Z11 infection group was strongly positive for the serological test, showing a DIVA capability of Z11ΔrfbG vaccination. Overall, our findings demonstrate the viability of the rfbG mutant as a live attenuated chicken vaccine that can discriminate between animals that have been immunized and those that have been infected. IMPORTANCE S. Enteritidis is a highly adapted pathogen that causes significant economic losses in the poultry industry around the world. Vaccination is an effective method of controlling S. Enteritidis infections. Here, we demonstrated that S. Enteritidis Z11ΔrfbG has the potential to be a safe, immunogenic, and DIVA vaccine candidate for the control of Salmonella infections in chickens. Z11ΔrfbG not only provided effective protection in chickens but also distinguished between infected and vaccinated chickens by serological tests.

ODP510 Pseudolymphoma of the Thyroid Gland in Association with Hashimoto's Thyroiditis: A Benign Lesion in Whitish Thyroid Gland

Abstract Background Pseudolymphoma or reactive lymphoid hyperplasia is a benign localized tumor-forming lymphoid hyperplasia found in various organs. Its occurrence in the thyroid gland is rare and could mimic malignant lesion. Here, we present a case of pseudolymphoma of the thyroid in a patient with Hashimoto's Thyroiditis. Case description A 24-year-old woman without underlying disease presented with incidentally found thyroid nodule. Ultrasound revealed mild thyroid enlargement with diffuse heterogeneous parenchymal echotexture. A 5×7×8.5-mm hypoechoic solid nodule with irregular margin was found in the left upper pole. No microcalcification was detected. Multiple subcentimeter lymph nodes at bilateral cervical group VI and left cervical group IV were also detected, measuring up to 5 mm in short axis. Fine-needle aspiration was performed and suggested malignancy (Bethesda class V). Laboratory testing showed euthyroid state with positive anti-thyroglobulin antibodies and anti-thyroid peroxidase antibodies. The blood test and ultrasound findings suggested the underlying of Hashimoto's thyroiditis. The patient underwent total thyroidectomy and lymph node dissection without postoperative complication. Gross examination of the thyroid showed multiple well-demarcated whitish nodular lesions, ranging from 2-10 mm, in the upper pole of both thyroid lobe and a well-circumscribed area of a 7-mm greyish nodule in left thyroid lobe. Microscopically, the whitish lesion in both lobe composed of hyperplastic lymphoid tissues with many follicular centers on the background of lymphocytic thyroiditis. The immunohistochemistry study revealed a polyclonal nature of the plasma cell infiltrates. No abnormal staining with AE1/AE3 or cyclin D1 was found. Pseudolymphoma was diagnosed based on these findings. Papillary thyroid microcarcinoma (6 mm) without capsular invasion was also diagnosed in the lesion of left mid lobe. The cervical lymph nodes showed metastatic papillary thyroid carcinoma (1.5 mm) in level III cervical lymph nodes. No perinodal extension was found. Postoperative course was unremarkable and the patient was in stable condition at 18 months after the operation. Conclusion Although primary thyroid lymphoma is often considered in patients with Hashimoto's thyroiditis. The possibility of pseudolymphoma characterized by the presence of well-demarcated pearly white nodules and polyclonal cell populations should also be considered. Presentation: No date and time listed

Atypical Lesions in Canine Leishmaniosis: Description of New Cases.

Simple SummaryCanine leishmaniosis is a zoonotic disease caused mainly by the protozoan Leishmania infantum that is endemic in the Mediterranean basin. The clinical signs and pathological characteristics have been extensively described; however, atypical lesions leading to clinical and pathological misdiagnosis have been sporadically reported. This study presents three cases of dogs experimentally infected with Leishmania infantum that showed gross lesions considered atypical of canine leishmaniosis and not previously reported. Macroscopic lesions were observed in the liver, spleen, and peritoneal cavity that corresponded to tan to whitish nodular lesions in all organs and multifocal irregular and linear whitish lesions in one of the livers that mimicked tumors. Microscopically, a marked granulomatous inflammation with a relative scarcity of parasites was observed in all the organs. In conclusion, microscopic and parasitological studies should be performed on atypical lesions observed in Leishmania-infected and non-infected dogs, especially in endemic regions. In addition, due to its zoonotic importance, leishmaniosis should be considered when atypical nodular lesions are observed in dogs from non-endemic regions with a history of travel to endemic regions.Pathological characteristics are well described in canine leishmaniosis (CanL). However, atypical lesions that can be confused with other pathologies or trigger unusual clinical signs are sporadically reported. Atypical lesions were observed during routine postmortem examination in three Leishmania-infected dogs and samples were taken for histopathological and immunohistochemical studies. Clinical signs, biochemical parameters, level of antibodies, and parasite detection by PCR were also evaluated. Atypical lesions were found in the peritoneal cavity, liver, and spleen. Splenomegalia and hepatomegalia were observed in all dogs. In addition, multifocal dark to white nodules of variable size were observed in the peritoneal cavity, liver, and spleen of one dog and in the spleen of the other two dogs. One dog presented diffuse irregular whitish lines with a threadlike appearance and another an intense fibrotic depression in the intermediate lobe. Microscopically, an intense granulomatous inflammation with abundant macrophages, a variable number of lymphocytes, and a low to moderate number of parasites was observed. This study represents the first description of granulomatous peritonitis associated with Leishmania in dogs. It also shows atypical macroscopic expression of hepatitis in CanL. In the absence of an adequate clinical history and laboratory analyses, certain lesions observed in CanL could admit alternative diagnoses.

S3463 Primary Intestinal Follicular Lymphoma

Introduction: Follicular Lymphoma (FL) mostly presents as a nodal lymphoma, however primary extranodal involvement is rare. The gastrointestinal tract is the most common site of extranodal FL, and with rates of FL increasing it remains important to recognize the characteristic endoscopic features of the disease. It typically carries an indolent course that may not even require treatment. We present a case of primary intestinal FL that involved the entire small intestine. Case Description/Methods: A 53-year-old Hispanic male with a history of gastrointestinal reflux disease (GERD), presented with refractory GERD symptoms despite maximal PPI therapy. An upper endoscopy was performed and revealed an irregular Z line, gastritis and numerous, patchy, small (< 1cm), white nodules in the second and third portion of the duodenum. Multiple biopsies were taken from the nodules. Pathology revealed Grade I-II FL. Capsule endoscopy was performed and revealed numerous similar lesions throughout the entire small intestine. He was referred to Oncology and underwent PET-CT scan which revealed multiple FDG-avid abdominopelvic lymph nodes. After discussion with Oncology, the patient elected for a watch and wait approach. Repeat PET-CT scan 6 months later revealed multiple abdominopelvic lymph nodes that are no longer FDG-avid. He remains asymptomatic and will be monitored closely off therapy. (Figure) Discussion: The most common primary intestinal lymphomas are diffuse large B-cell lymphoma (DLBCL) and mucosa associated lymphoid tissue (MALT) Lymphoma. FL only comprises approximately 1-2% of primary intestinal lymphomas. The small intestine is the most common location, with the second portion of the duodenum as the most likely site of involvement. It is rarely seen in the colon and stomach and there are no reported cases of esophageal involvement. Rates of diagnosis are on the rise, thus highlighting the importance of endoscopic recognition as it may often be seen in the second portion of the duodenum on routine upper endoscopy. Given the indolent course of FL, a watch and wait approach may be reasonable. Other options for therapy include chemotherapy, Rituximab, or radiation.Figure 1.: White nodular mass in duodenum visualized on capsule endoscopy consistent with patient's known diagnosis of Follicular Lymphoma.

S3443 Multifocal Duodenal-type Follicular Lymphoma Found Incidentally on Diagnostic Endoscopy

Introduction: Follicular lymphoma (FL) accounts for approximately 4% of gastrointestinal (GI) lymphomas (1). Of the follicular lymphomas found in the GI tract, duodenal-type follicular lymphoma (D-FL) make up 38-81% of cases (2-4). D-FL is often incidentally discovered, lack invasion into deeper layers of the GI tract, and are indolent in nature (5). The clinical stage at time of diagnosis often predicts probability of disease progression (6). Given the excellent prognosis and rare occurrence of progression to high stage FL or transformation to diffuse large B cell lymphoma, a “wait and see” therapeutic approach is often taken (4,7). We report a case of D-FL here. Case Description/Methods: A 39-year-old female with no pertinent past medical history presented with refractory acid reflux. Her endoscopy was notable for gastritis, duodenal atrophy, and three 5-mm pale nodules in the second part of the duodenum (Figure 1A-1C). Initial biopsy of these polyps showed atypical lymphoid follicular aggregates. Outside pathologists’ subsequent review noted atypical lymphoid cells positive for CD10, BCL-2, BCL-5, and CD20 markers, consistent with duodenal follicular lymphoma. Further workup with small bowel enteroscopy to the mid-jejunum and colonoscopy were normal. LDH, SPEP with immunofixation, HIV, hepatitis serologies, and full body CT were unremarkable. The patient was diagnosed with stage I D-FL per the Lugano staging system for gastrointestinal lymphomas, and a “wait and wait” approach was recommended by oncology. Discussion: D-FL typically presents with multiple low-stage, white nodules in the second portion of the duodenum, as in our case. Because lesions are rarely solitary in 78-85% D-FL cases, thorough small bowel assessment with enteroscopy or capsule endoscopy is warranted (3,4). Radiation has been shown to be effective in limited disease and is the most common form of treatment (8-10). Chemotherapy, Rituximab, and surgery can also used as monotherapy or in combination therapy (4). However, the “watch and wait” approach has been found to be equally effective and is the most common approach amongst oncologists in the United States (11).Figure 1.: Endoscopic images of the duodenal second portion. Three distinct 5-mm pale nodules were seen and biopsies. First, second, and third lesions are seen in figure 1A, 1B, and 1C, respectively.

Transcriptomic Identification of a Unique Set of Nodule-Specific Cysteine-Rich Peptides Expressed in the Nitrogen-Fixing Root Nodule of Astragalus sinicus.

Legumes in the inverted repeat-lacking clade (IRLC) each produce a unique set of nodule-specific cysteine-rich (NCR) peptides, which act in concert to determine the terminal differentiation of nitrogen-fixing bacteroid. IRLC legumes differ greatly in their numbers of NCR and sequence diversity. This raises the significant question how bacteroid differentiation is collectively controlled by the specific NCR repertoire of an IRLC legume. Astragalus sinicus is an IRLC legume that forms indeterminate nodules with its microsymbiont Mesorhizobium huakuii 7653R. Here, we performed transcriptome analysis of root and nodule samples at 3, 7, 14, 28 days postinoculation with M. huakuii 7653R and its isogenic ∆bacA mutant. BacA is a broad-specificity peptide transporter required for the host-derived NCRs to target rhizobial cells. A total of 167 NCRs were identified in the RNA transcripts. Comparative sequence and electrochemical analysis revealed that A. sinicus NCRs (AsNCRs) are dominated by a unique cationic group (termed subgroup C), whose mature portion is relatively long (>60 amino acids) and phylogenetically distinct and possessing six highly conserved cysteine residues. Subsequent functional characterization showed that a 7653R variant harboring AsNCR083 (a representative of subgroup C AsNCR) displayed significant growth inhibition in laboratory media and formed ineffective white nodules on A. sinicus with irregular symbiosomes. Finally, bacterial two-hybrid analysis led to the identification of GroEL1 and GroEL3 as the molecular targets of AsNCR067 and AsNCR076. Together, our data contribute to a systematic understanding of the NCR repertoire associated with the A. sinicus and M. huakuii symbiosis. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Detection of lymphocystis disease virus (LCDV) from yellowbar angelfish (Pomacanthus maculosus Forsskål, 1775) in Iran: Histopathological and phylogenetic analysis

Lymphocystis disease (LCD) is a benign viral disease characterized by the appearance of hypertrophic fibroblastic cells in the connective tissues of fish. In December 2021, a group of yellowbar angelfish (Pomacanthus maculosus Forsskål, 1775) which had significant mortalities (10%) and showed whitish nodules on the fins and skin, were packed in water-filled plastic bags, supplied with oxygen, and transported to the Ornamental Fish Clinic, Faculty of Veterinary Medicine, University of Tehran (Tehran, Iran). Following the clinical inspection and observation of whitish clusters of nodules mostly on the fins and skin by stereomicroscopy, wet smears of skin and fins revealed numerous hypertrophic lymphocystis cells. Histopathological study of the whitish nodules in skin and fins revealed many hypertrophic cells with thick hyaline capsules, irregular nucleus, and multiple intracytoplasmic inclusion bodies. In addition to the extension of hypertrophic lymphocystis cells' growth until the superficial muscle layer, infiltration of inflammatory cells and hemorrhage between hypertrophic cells are also observed. The hyaline capsule of hypertrophic fibroblasts stained with the PAS. Molecular characterization (PCR) confirmed the presence of Lymphocystis disease virus (LCDV) in the external nodules and the internal organs homogenate of the infected fish. Sequence analysis of the MCP gene of the detected virus (IR_LCDV_RGZIS) assigned it to genogroup 5. This is the first detection and characterization of LCDV in yellowbar angelfish (Pomacanthus maculosus) in Iran.

Isolation and characterization of avian leukosis virus subgroup J associated with hemangioma and myelocytoma in layer chickens in China.

A strain of avian leukosis virus (ALV) belonging to a new envelope subgroup J (ALV-J) emerged in 1988 as a new subgroup of ALV and spread rapidly throughout the world. Due to the infection and spread of ALV-J, the global poultry industry experienced a significant loss. Although the disease had been prevented and controlled effectively by culling domestic chickens in the infected zone, a few field cases of ALV-J infection were reported in China in recent years. This study was conducted to characterize the genome and analyze the lesions and histopathology of the ALV-J strain named HB2020, which was isolated from layer chickens in Hubei Province, China. The full-length proviral genome sequence analysis of ALV-J HB2020 revealed that it was a recombinant strain of ev-1 and HPRS-103 in the gag gene in comparison to ALV-J prototype HPRS-103. In the 3′-untranslated region (3'UTR) of the nucleotide sequence, there were found 205-base pairs (bp) deletion, of which 175 were detected in the redundant transmembrane (rTM) region. Besides, the surface glycoprotein gene gp85 had five mutations in a conservative site, whereas the transmembrane protein gene gp37 was relatively conserved. The animal experiments conducted later on this strain have shown that HB2020 can cause various neoplastic lesions in chickens, including enlarged livers with hemangiomas and spleens with white nodules. Additionally, as the exposure time increased, the number of tumor cells that resembled myelocytes in the blood smears of infected chickens gradually increased. These results indicated that HB2020 on recombination with ALV subgroup E (ALV-E) and ALV-J could induce severe hemangiomas and myelocytomas. This inference might provide a molecular basis for further research about the pathogenicity of ALV and emphasize the need for control and prevention of avian leukosis.