Transmissibility of Mycobacterium pinnipedii in a murine model.

The causative agent of tuberculosis in pinnipeds is Mycobacterium pinnipedii, a member of the Mycobacterium tuberculosis complex (MTC). The natural hosts are pinnipeds; however, other non-marine mammals, including humans, can also be infected. The transmissibility of a pathogen is related to its virulence. The transmissibility of a M. pinnipedii strain (i.e., 1856) was investigated in a murine model and compared with that of two Mycobacterium bovis strains (i.e., 534 and 04-303) with different reported virulence. Non-inoculated mice (sentinels) were co-housed with intratracheally inoculated mice. Detailed inspection of mice to search for visible tuberculosis lesions in the lungs and spleen was performed, and bacillus viability at 30, 60, and 90 days post-inoculation (dpi) was assayed. A transmissibility of 100% was recorded at 30 dpi in sentinel mice co-housed with the inoculated mice from the M. pinnipedii and M. bovis 04-303 groups, as evidenced by the recovery of viable M. pinnipedii and M. bovis from the lungs of sentinel mice. Mice inoculated with M. pinnipedii (1856) and M. bovis (534) survived until euthanized, whereas five of the M. bovis 04-303-inoculated mice died at 17 dpi. This study constitutes the first report of the transmissibility of a M. pinnipedii strain in mice and confirms the utility of this experimental model to study virulence features such as the transmission of poorly characterized MTC species.

Correlation between spleen density and prognostic outcomes in patients with colorectal cancer after curative resection.

OBJECTIVE: The objective of this study was to investigate the correlation between spleen density and the prognostic outcomes of patients who underwent curative resection for colorectal cancer (CRC). METHODS: The clinical data of patients who were diagnosed with CRC and underwent radical resection were retrospectively analyzed. Spleen density was determined using computed tomography. Analysis of spleen density in relation to overall survival (OS) and disease-free survival (DFS) utilizing the Kaplan-Meier method. Univariate and multivariate Cox regression models were used to screen for independent prognostic factors, and a nomogram was constructed to predict OS and DFS. Moreover, internally validated using a bootstrap resamplling method. RESULTS: Two hundred twelve patients were included, of whom 23 (10.85%) were defined as having a diffuse reduction of spleen density (DROSD) based on diagnostic cutoff values (spleen density≦37.00HU). Kaplan-Meier analysis indicated that patients with DROSD had worse OS and DFS than those non-DROSD (P < 0.05). Multivariate Cox regression analysis revealed that DROSD, carbohydrate antigen 199 (CA199) > 37 U/mL, tumor node metastasis (TNM) stage III-IV, laparoscopy-assisted operation and American Society of Anesthesiology (ASA) score were independent risk factors for 3-year DFS. DROSD, CA199 > 37 U/mL, TNM stage III-IV, hypoalbuminemia, laparoscopy-assisted operation and ASA score were chosen as predictors of for 3-year OS. Nomograms showed satisfactory accuracy in predicting OS and DFS using calibration curves, decision curve analysis and bootstrap resamplling method. CONCLUSION: Patients with DROSD who underwent curative resection have worse 3-year DFS and OS. The nomogram demonstrated good performance, particularly in predicting 3-year DFS with a net clinical benefit superior to well-established risk calculator.

Splenic B-cell lymphoma/leukemia with prominent nucleoli: A three-case series of the newly named old entity and review of literature.

CONTEXT: Splenic B-cell lymphoma/leukemia with prominent nucleoli (SBLPN) aka hairy cell leukemia variant (HCL-v) is a rare B-cell chronic lymphoproliferative disorder. The main diagnostic challenge is to differentiate SBLPN from Classical hairy cell leukemia (HCL-c), as the former faces inferior responses to therapies and a poor prognosis. AIMS: The aim is to discuss the clinic-hematological and immunophenotyping findings of three cases of SBLPN. SETTINGS AND DESIGN: This is a retrospective observational study. METHODS AND MATERIAL: From the year 2011 to 2021, flow cytometry of all the cases with HCL diagnosis was reviewed, and three cases with negative or dim CD25 and hematological presentation matching with SBLPN were picked up. STATISTICAL ANALYSIS USED: Descriptive statistics is used. RESULTS: All the cases were male. The age ranges from 43 to 64 years. Median hemoglobin concentration, total leucocyte count, and platelet count were 8.6 g/dL, 6.9 × 109/L, and 53 × 109/L, respectively. The atypical cells were medium to large. All three showed prominent nucleoli. Bone marrow biopsies showed an interstitial pattern of infiltration in all the cases. The hairy cells were positive for CD20, CD11c, and CD103. CD25 was dim positive in one case. Annexin A1 was negative in all three cases. BRAF V600E mutation analysis was done in one case and turned out negative for the mutation. CONCLUSIONS: SBLPN is a rare entity, usually on-flow cytometry CD25 negative. However, in dim CD25-positive cases, BRAFV600E mutational analysis helps in discerning SBLPN diagnosis and differentiating it from HCL-c.

Intravital imaging of splenic classical monocytes modifying the hepatic CX3CR1+ cells motility to exacerbate liver fibrosis via spleen-liver axis.

CX3CR1+ cells play a crucial role in liver fibrosis progression. However, changes in the migratory behavior and spatial distribution of spleen-derived and hepatic CX3CR1+ cells in the fibrotic liver as well as their influence on the liver fibrosis remain unclear. METHODS: The CX3CR1GFP/+ transgenic mice and CX3CR1-KikGR transgenic mice were used to establish the CCl4-induced liver fibrosis model. Splenectomy, adoptive transfusion of splenocytes, in vivo photoconversion of splenic CX3CR1+ cells and intravital imaging were performed to study the spatial distribution, migration and movement behavior, and regulatory function of CX3CR1+ cells in liver fibrosis. RESULTS: Intravital imaging revealed that the CX3CR1GFP cells accumulated into the fibrotic liver and tended to accumulate towards the central vein (CV) in the hepatic lobules. Two subtypes of hepatic CX3CR1+ cells existed in the fibrotic liver. The first subtype was the interacting CX3CR1GFP cells, most of which were observed to distribute in the liver parenchyma and had a higher process velocity; the second subtype was mobile CX3CR1GFP cells, most of which were present in the hepatic vessels with a faster moving speed. Splenectomy ameliorated liver fibrosis and decreased the number of CX3CR1+ cells in the fibrotic liver. Moreover, splenectomy rearranged CX3CR1GFP cells to the boundary of the hepatic lobule, reduced the process velocity of interacting CX3CR1GFP cells and decreased the number and mobility of mobile CX3CR1GFP cells in the fibrotic liver. Transfusion of spleen-derived classical monocytes increased the process velocity and mobility of hepatic endogenous CX3CR1GFP cells and facilitated liver fibrosis progression via the production of proinflammatory and profibrotic cytokines. The photoconverted splenic CX3CR1+ KikRed+ cells were observed to leave the spleen, accumulate into the fibrotic liver and contact with hepatic CX3CR1+ KikGreen+ cells during hepatic fibrosis. CONCLUSION: The splenic CX3CR1+ monocytes with classical phenotype migrated from the spleen to the fibrotic liver, modifying the migratory behavior of hepatic endogenous CX3CR1GFP cells and exacerbating liver fibrosis via the secretion of cytokines. This study reveals that splenic CX3CR1+ classical monocytes are a key driver of liver fibrosis via the spleen-liver axis and may be potential candidate targets for the treatment of chronic liver fibrosis.

Changes in splenic tissue and immune response profile of Schistosoma mansoni infected mice submitted to chronic ethanol intake.

In Schistosoma mansoni infection, the spleen is one of the organs affected, causing its enlargement (splenomegaly). Intake of ethanol through alcoholic beverages can cause spleen atrophy and interfere with immune activity. To gain knowledge of this association on the spleen and on the immune response profile, male mice were used as an experimental model. These animals were divided into four groups: C. control; EC. uninfected/ethanol gavage; I. infected; and IE. infected/ethanol gavage. Groups I and IE were infected with about 100 cercariae (BH strain) of S. mansoni and in the fifth week of infection, gavage 200 µL/day/animal of 18 % ethanol was started for 28 consecutive days. At the end of the gavage (9th week of infection) all animals were euthanized. The spleen was removed and longitudinally divided in two parts. After histological processing, the sections were stained with H&E and Gomori's Reticulin for histopathological and stereological analyses, white pulp morphometry and quantification of megakaryocytes. The other fragment was macerated (in laminar flow) and the cell suspension, after adjusting the concentration (2 × 106), was plated to obtain cytokines produced by spleen cells that were measured by flow cytometry (Citometric Bead Array). Histopathological and quantitative analyzes in the spleen of the IE group showed an increase in the number of trabeculae and megakaryocytes, a decrease in reticular fibers, as well as important organizational changes in the white pulp and red pulp. Due to the decrease in the levels of cytokines measured and the result of the calculation of the ratio between the IFN-y and IL-10 cytokines (p = 0.0079) of the infected groups, we suggest that ethanol decreased the inflammatory and anti-inflammatory response generated by the infection (group IE, the production of cytokines was significantly decreased (p < 0.01). These changes demonstrate that ethanol ingestion interferes with some parameters of experimental S. mansoni infection, such as changes in splenic tissue and in the pattern of cytokine production.

Single-cell profiling of African swine fever virus disease in the pig spleen reveals viral and host dynamics.

African swine fever, one of the major viral diseases of swine, poses an imminent threat to the global pig industry. The high-efficient replication of the causative agent African swine fever virus (ASFV) in various organs in pigs greatly contributes to the disease. However, how ASFV manipulates the cell population to drive high-efficient replication of the virus in vivo remains unclear. Here, we found that the spleen reveals the most severe pathological manifestation with the highest viral loads among various organs in pigs during ASFV infection. By using single-cell-RNA-sequencing technology and multiple methods, we determined that macrophages and monocytes are the major cell types infected by ASFV in the spleen, showing high viral-load heterogeneity. A rare subpopulation of immature monocytes represents the major population infected at late infection stage. ASFV causes massive death of macrophages, but shifts its infection into these monocytes which significantly arise after the infection. The apoptosis, interferon response, and antigen-presentation capacity are inhibited in these monocytes which benefits prolonged infection of ASFV in vivo. Until now, the role of immature monocytes as an important target by ASFV has been overlooked due to that they do not express classical monocyte marker CD14. The present study indicates that the shift of viral infection from macrophages to the immature monocytes is critical for maintaining prolonged ASFV infection in vivo. This study sheds light on ASFV tropism, replication, and infection dynamics, and elicited immune response, which may instruct future research on antiviral strategies.

Minimally invasive splenectomy is associated with a low perioperative complication rate and short operative time in cats.

OBJECTIVE: To report the perioperative outcome and complications in cats undergoing minimally invasive splenectomy. ANIMALS: 17 client-owned cats. METHODS: Perioperative data were collected from cats undergoing minimally invasive splenectomy from September 2010 to June 2023. Data included history, signalment, preoperative examination and diagnostic testing results, operative technique and time, perioperative outcomes, complications, hospitalization duration, histopathological diagnosis, and outcome. RESULTS: 13 spayed females and 4 neutered males were included, with a median age of 144 months (48 to 196 months). Seven cats underwent total laparoscopic splenectomy (TLS), with 1 cat requiring conversion from TLS to laparoscopic-assisted splenectomy (LAS) due to splenomegaly and an additional cat requiring conversion from TLS to open splenectomy due to uncontrollable splenic capsular hemorrhage. Ten cats underwent LAS, with 1 cat requiring conversion to open splenectomy due to splenomegaly. Additional procedures were performed in 13 cats, with the most common being liver biopsy in 10 cats. Median operative times were 50 minutes (45 to 90 minutes) for TLS and 35 minutes (25 to 80 minutes) for LAS. An intraoperative complication occurred in 1 cat. All but 1 cat survived to discharge. Median follow-up time was 234 days (18 to 1,761 days), with 15 of 16 cats confirmed alive at 30 days and 9 of 16 cats alive at 180 days postoperatively. CLINICAL RELEVANCE: Minimally invasive splenectomy in this cohort of cats was associated with short operative times and a low perioperative complication rate. Veterinary surgeons may consider minimally invasive splenectomy as an efficient and feasible technique in the treatment of splenomegaly or modestly sized splenic masses for diagnostic and therapeutic purposes in cats.

FDG PET/CT Imaging of Liver and Spleen Histiocytic Sarcoma.

ABSTRACT: Histiocytic sarcoma is a tumor of the lymphohematopoietic system characterized by macrophage morphology and immunophenotype. Here, we report FDG PET/CT images of a 50-year-old man with coexisting histiocytic sarcoma of the liver and spleen. Images showed multiple enhanced uptake lesions of FDG in both the liver and spleen. Ultimately, histiocytic sarcoma was confirmed by the biopsy histopathology.

A Multicenter Study of Needle Size and Safety for Splenic Biopsy.

Background Splenic biopsy is rarely performed because of the perceived risk of hemorrhagic complications. Purpose To evaluate the safety of large bore (≥18 gauge) image-guided splenic biopsy. Materials and Methods This retrospective study included consecutive adult patients who underwent US- or CT-guided splenic biopsy between March 2001 and March 2022 at eight academic institutions in the United States. Biopsies were performed with needles that were 18 gauge or larger, with a comparison group of biopsies with needles smaller than 18 gauge. The primary outcome was significant bleeding after the procedure, defined by the presence of bleeding at CT performed within 30 days or angiography and/or surgery performed to manage the bleeding. Categorical variables were compared using the χ2 test and medians were compared using the Mann-Whitney test. Results A total of 239 patients (median age, 63 years; IQR, 50-71 years; 116 of 239 [48.5%] female patients) underwent splenic biopsy with an 18-gauge or smaller needle and 139 patients (median age, 58 years [IQR, 49-69 years]; 66 of 139 [47.5%] female patients) underwent biopsy with a needle larger than 18 gauge. Bleeding was detected in 20 of 239 (8.4%) patients in the 18-gauge or smaller group and 11 of 139 (7.9%) in the larger than 18-gauge group. Bleeding was treated in five of 239 (2.1%) patients in the 18-gauge or smaller group and one of 139 (1%) in the larger than 18-gauge group. No deaths related to the biopsy procedure were recorded during the study period. Patients with bleeding after biopsy had smaller lesions compared with patients without bleeding (median, 2.1 cm [IQR, 1.6-5.4 cm] vs 3.5 cm [IQR, 2-6.8 cm], respectively; P = .03). Patients with a history of lymphoma or leukemia showed a lower incidence of bleeding than patients without this history (three of 90 [3%] vs 28 of 288 [9.7%], respectively; P = .05). Conclusion Bleeding after splenic biopsy with a needle 18 gauge or larger was similar to biopsy with a needle smaller than 18 gauge and seen in 8% of procedures overall, with 2% overall requiring treatment. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Grant in this issue.

EBV-Positive Inflammatory Follicular Dendritic Cell Sarcoma of the Spleen: Report of an Aggressive Form With Molecular Characterization.

EBV-positive inflammatory follicular dendritic cell sarcoma (EBV+ inflammatory FDCS) is a rare neoplasm almost exclusively located in the spleen or liver. It is characterized by a proliferation of EBV-positive spindle-shaped cells bearing follicular dendritic cell markers, associated with an abundant lymphoplasmacytic infiltrate. EBV+ inflammatory FDCS is often asymptomatic or responsible for mild symptoms. It usually displays an indolent course and its prognosis is excellent after tumor removal, although relapsing and metastatic forms exist. Herein, we describe an aggressive form of splenic EBV+ inflammatory FDCS in a 79-year-old woman presenting with abdominal pain, deterioration of general health status, major inflammatory syndrome, and symptomatic hypercalcemia. A splenectomy was performed leading to a rapid improvement in her clinical condition and normalization of laboratory abnormalities. Unfortunately, her symptoms and laboratory abnormalities reappeared 4 months later. Computed tomography showed a mass in the splenectomy site and multiple liver and peritoneal nodules. Further analyses were performed on tumor tissue and showed positive phospho-ERK staining of tumoral cells indicating activation of MAPK pathway. Inactivating mutations were found on CDKN2A and NF1 genes. Subsequently, the patient's condition deteriorated rapidly. Since interleukin-6 levels were dramatically increased, tocilizumab was used but only had a transient effect on the patient's symptoms and inflammatory syndrome. Antitumor agent gemcitabine was initiated but her clinical condition continued to deteriorate and the patient died 2 weeks later. The management of aggressive forms of EBV+ inflammatory FDCS remains challenging. However, since these tumors seem to display genetic alterations, better characterization could lead to molecular targeted therapies.

Atypical Cat Scratch Disease With Splenic Lesion Mimicking Kawasaki Disease in a Healthy 5-Year-old Girl.

BACKGROUND: Atypical cat scratch disease (CSD) and Kawasaki disease (KD) are differential diagnoses of pediatric febrile illnesses. Diagnosing atypical CSD can be challenging because of its wide range of symptoms. However, its similarity to KD has rarely been addressed. METHODS: We present the case of a 5-year-old girl with atypical CSD and splenic lesions who fulfilled the diagnostic criteria for KD. We also conducted a literature review of previous cases in which CSD was suspected alongside KD and detailed the diagnosis and treatment processes. RESULTS: A previously healthy 5-year-old girl with prolonged fever and symptoms resembling those of KD was admitted to our hospital. There was no evidence of an abnormal coronary artery, and her condition did not improve after the initial treatment for KD and bacterial infection. A history of contact with cats and multiple granulomatous lesions in the spleen on abdominal ultrasonography led to a clinical diagnosis of atypical CSD. Trimethoprim-sulfamethoxazole treatment resulted in symptom resolution. Elevated serum Bartonella henselae IgG and IgM antibodies confirmed the diagnosis of CSD. In this case, we avoided second-line treatment for KD with an alternative CSD diagnosis. Additionally, we identified 4 documented cases of CSD presenting with KD-like features in the literature. Intravenous immunoglobulin was ineffective in all cases, including the present case. CONCLUSIONS: In cases of atypical CSD where KD is suspected, actively seeking organ-specific symptoms may facilitate an early clinical diagnosis of CSD. Adopting this approach could yield multiple advantages, including reduced invasiveness for the patient and decreased healthcare-related expenditures.

The Gastrohepatic Ligament Approach Using Multiple Traction Tapes in Laparoscopic Spleen-Preserving Distal Pancreatectomy with Preservation of Splenic Vessels (with Video).

BACKGROUND: The gastrohepatic ligament approach is a form of robot-assisted spleen-preserving distal pancreatectomy (SPDP).1,2 This approach does not require omentum transection, peri-splenic dissection, or stomach traction. METHODS: Considering the advantages of preserving collateral pathways around the spleen, the authors performed the gastrohepatic ligament approach in laparoscopic SPDP while preserving splenic vessels (LSPDP), with specific modifications for laparoscopic surgery. The following surgical technique was performed. First, the gastrohepatic ligament was divided extensively, and all subsequent procedures were performed through the gastrohepatic ligament route. The superior and inferior borders of the pancreas then were dissected to encircle the common hepatic and splenic arteries with vessel loops and to expose the superior mesenteric vein (SMV) and portal vein. After taping of the pancreas on the SMV, the pancreas was divided using a linear stapler. Next, the pancreas was dissected from proximal to distal with preservation of the splenic vessels. Re-taping and traction of the splenic vessels and pancreas could facilitate the dissection of the pancreas body, especially at the splenic hilum. The appropriate counter traction using traction tapes allowed efficient laparoscopic procedures. The LSPDP was performed for three patients, including one obese patient (body mass index, 36 kg/m2) and two patients with an anomalous left hepatic artery branching from the left gastric artery. RESULTS: The mean operation time was 186 min, and the intraoperative blood loss was 37 mL. CONCLUSION: The gastrohepatic ligament approach could be an option for performing LSPDP with the counter traction technique for low-grade malignant tumors.

Improving the chances of response to splenectomy in immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by isolated thrombocytopenia. Its pathogenesis is complex relying in large part on destruction of platelets recognized by autoantibodies within the spleen. However, other mechanisms, such as platelet desialylation, may play a role in platelet reduction by accelerating their clearance in the liver. In their study, Mendoza and colleagues reported on platelet scintigraphy performed in 51 ITP patients, showing a response in 87.5% when the sequestration occurred in the spleen versus 45% in case of non-splenic destruction. Platelet desialylation was also measured after splenectomy and found to be higher in non-responder patients. These latter results, while requiring confirmation prior to splenectomy, support platelet desialylation may also be a potential biomarker of non-response to splenectomy. Commentary on: Mendoza et al. Study of platelet kinetics in immune thrombocytopenia to predict splenectomy response. Br J Haematol 2024;204:315-323.

Splenic stromal sarcomas in dogs: Outcome and clinicopathological prognostic factors in 32 cases.

Due to the low frequency and the changes in diagnostic techniques and terminology during the last few years, only little clinical information is available on splenic stromal sarcoma (SSS). This multi-institutional study aimed at gathering clinical cases of SSS in dogs and investigates their clinical behaviour, as well as analyse possible clinicopathological prognostic factors, including the use of adjuvant therapy. Dogs with a histologically confirmed SSS that underwent splenectomy were retrospectively included. To be included in the study, either FFPE tissue blocks or multiple tissue sections had to be available for histopathologic and immunohistochemical revision. Clinical and pathological variables, along with adjuvant therapy data, were collected. Cumulative incidence of metastatic disease was analysed through univariate and bivariate analyses. The impact of adjuvant chemotherapy on metastasis incidence and survival was assessed, considering an estimated propensity score. A total of 32 dogs were included. Among them, 22 developed metastases with an incidence of 37.5%, 59.38%, and 65.94% at 6, 12, and 24 months, respectively. Univariate analysis identified mitotic count, total scoring, and necrosis as prognostic factors. In bivariate analysis, mitotic count remained prognostic. The administration of adjuvant chemotherapy did not have an impact on metastasis incidence or survival time. The study found that dogs with SSSs are at high risk of metastasis, although a small subgroup may experience longer survival after splenectomy. Mitotic count was the only variable having a reliable prognostic impact. Adjuvant chemotherapy did not appear to decrease the incidence of metastasis or prolong survival in these dogs.

Meta-analysis of laparoscopic spleen-preserving distal pancreatectomy versus laparoscopic distal pancreatectomy with splenectomy: An insight into confounding by indication.

AIMS: To evaluate comparative outcomes of laparoscopic spleen-preserving distal pancreatectomy (LSPDP) and laparoscopic distal pancreatectomy with splenectomy (LDPS). METHODS: A systematic search of multiple electronic data sources and bibliographic reference lists were conducted. Comparative studies reporting outcomes of LSPDP and LDPS were considered followed by evaluation of the associated risk of bias according to ROBINS-I tool. Perioperative complications, clinically important postoperative pancreatic fistula (POPF), infectious complications, blood loss, conversion to open, operative time and duration of hospital stay were the investigated outcome parameters. RESULTS: Nineteen studies were identified enrolling 3739 patients of whom 1860 patients underwent LSPDP and the remaining 1879 patients had LDPS. The patients in the LSPDP and LDPS groups were of comparable age (p = 0.73), gender (p = 0.59), and BMI (p = 0.07). However, the patient in the LDPS group had larger tumour size (p = 0.0004) and more malignant lesions (p = 0.02). LSPDP was associated with significantly lower POPF (OR:0.65, p = 0.02), blood loss (MD:-28.30, p = 0.001), and conversion to open (OR:0.48, p < 0.0001) compared to LDPS. Moreover, it was associated with significantly shorter procedure time (MD: -22.06, p = 0.0009) and length of hospital stay (MD: -0.75, p = 0.005). However, no significant differences were identified in overall perioperative (OR:0.89, p = 0.25) or infectious (OR:0.67, p = 0.05) complications between two groups. CONCLUSIONS: LSPDP seems to be associated with lower POPF, bleeding and conversion to open compared to LDPS in patients with small-sized benign tumours. Moreover, it may be quicker and reduce hospital stay. Nevertheless, such advantages are of doubtful merit about large-sized or malignant tumours. The available evidence is subject to confounding by indication.

Untangling hairy cell leukaemia (HCL) variant and other HCL-like disorders: Diagnosis and treatment.

The variant form of hairy cell leukaemia (HCL-V) is a rare disease very different from hairy cell leukaemia (HCL), which is a very well-defined entity. The 5th WHO edition (Leukemia, 36, 2022 and 1720) classification (WHO-HAEM5) introduced splenic lymphomas/leukaemias including four different entities: (1) HCL, (2) splenic marginal zone lymphoma (SMZL) with circulating villous cells in the peripheral blood, (3) splenic lymphoma with prominent nucleolus (SLPN), which replaced HCL-V and CD5 negative B-prolymphocytic leukaemia (B-PLL), and (4) splenic diffuse red pulp lymphoma (SDRPL). All these entities have to be distinguished because of a different clinical course and the need for a different treatment. The diagnosis can be challenging because of complex cases and overlap and/or grey zones between all the entities and needs integrating clinical, histologic, immunophenotypic, cytogenetic and molecular data. We review the diagnostic criteria including clinical, immunophenotypic and molecular characteristics of patients with HCL-V and other HCL-like disorders including HCL, SDRPL, SMZL, B-PLL and the Japanese form of HCL. We also discuss the different criteria allowing us to separate these different entities and we will update the recent therapeutic options that have emerged, in particular the advances with chemoimmunotherapy and/or targeted therapies.

Relationship Between Spleen Pathologic Changes and Spleen Stiffness in Portal Hypertension Rat Model.

OBJECTIVE: The aim of the study described here was to explore the influence of splenic pathology and hemodynamic parameters on spleen stiffness in portal hypertension (PH). METHODS: A Sprague‒Dawley rat model of PH (n = 34) induced by CCl4 was established, and 9 normal rats were used as controls. All animals underwent a routine ultrasound examination, spleen stiffness measurement (SSM), liver stiffness measurement (LSM), portal vein pressure (PVP) measurement and histopathologic assessment. The diagnostic performance of SSM and LSM in PH was evaluated. SSMs were compared among the groups at different pathologic and hemodynamic levels. Multiple linear regression was used to analyze the factors affecting SSM. RESULTS: SSM had excellent diagnostic efficacy for PH (area under the receiver operating characteristic curve [AUC] = 0.900) and was superior to LSM (AUC = 0.794). In a rat model of PH, pathologic changes such as splenic sinus widening, thickening of the splenic capsule and an increase in collagen fibers were observed in the spleen. There were significant differences in SSM at different splenic capsule thicknesses and splenic sinus widths (all p values <0.05), but there were no significant differences in the SSM at different levels of the splenic collagen fiber area and red pulp area (all p values >0.05). In addition, there were significant differences in SSM at different levels of portal vein diameter, blood flow and congestion index (all p values <0.05). Multiple linear regression analysis revealed that PVP, portal vein congestion index and splenic capsule thickness were significantly associated with SSM. CONCLUSION: SSM is a good non-invasive way to assess PH. PVP, splenic capsule thickness and portal vein congestion index are responsible for spleen stiffness but not the proliferation of splenic fibrous tissue.

[A Case of Pseudocirrhosis during Chemotherapy for Breast Cancer with Liver Metastases].

A 60-year-old woman was undergoing chemotherapy for triple-negative breast cancer and multiple liver metastases. One year and 3 months after the start of treatment, blood tests showed worsening liver function and a decrease in the platelet count. Multiple liver metastases tend to shrink on computed tomography, but pseudocirrhosis was suspected because the right lobe of the liver had atrophied and the marginal irregularities were conspicuous. The platelet count decreased because of hypersplenism, and continuing chemotherapy was difficult. Splenic artery embolization was performed by the internal medicine department, and chemotherapy was resumed once the platelet count recovered. Imaging findings consistent with cirrhosis without the typical cirrhosis histopathology are considered as pseudocirrhosis. This phenomenon has been reported for breast cancer. During chemotherapy for liver metastases, attention should be paid to its appearance. Furthermore, liver cirrhosis should be controlled, and chemotherapy should be continued in coordination with the internal medicine department.

T-cell lymphoma involving the rectum of a dog.

A mediastinal mass was diagnosed in a 7-year-4-month-old neutered female mixed breed dog following a 3-week history of lethargy, hyporexia and pyrexia. Bi-cavitary imaging, needle aspirate cytology and flow cytometry confirmed WHO clinical stage IVb, intermediate to large T-cell lymphoma involving the mediastinum, liver and spleen. The dog initially responded to a multidrug chemotherapy protocol but clinical deterioration occurred 3 months later. The dog presented with anorexia, vomiting and diarrhoea, associated with marked faecal tenesmus and haematochezia, initially believed by the primary care practitioner to be related to chemotherapy toxicity. However, rectal examination revealed multiple sessile and pedunculated masses. Further diagnostic imaging, cytology and flow cytometry confirmed progressive disease, including T-cell lymphoma of the rectum. Histology and immunohistochemistry confirmed an infiltrate of intermediate-sized CD3-positive neoplastic cells that expanded the rectal mucosa. Rectal lymphoma is uncommon in dogs and previous cases have been B cell in origin. In this report we describe the clinical presentation and macro- and microscopic findings of a case of canine T-cell lymphoma involving the rectum.

B-cell leukemia in an adult sheep.

B-cell leukemia is a rare form of hematologic neoplasia in sheep, especially in adult animals. We present a case report of a 5-year-old WhiteFace Sheep wether with suspected acute lymphoblastic leukemia. The patient, a second-generation relative of ewes experimentally inoculated with atypical scrapie, exhibited acute lethargy and loss of appetite. Laboratory investigation revealed marked leukocytosis, lymphocytosis, and abnormal serum chemistry panel results. Microscopic examination of blood and bone marrow smears exhibited a high percentage of large neoplastic cells with lymphoid characteristics. Histopathologic analysis of the spleen, liver, lungs, and other organs confirmed the presence of widespread tissue infiltration by neoplastic cells. Immunohistochemical labeling demonstrated strong intracytoplasmic labeling for CD20, consistent with B-cell neoplasia. Flow cytometric analysis confirmed the B-cell lineage of the neoplastic cells. Screening for bovine leukemia virus, which can experimentally cause leukemia in sheep, yielded a negative result. In this case, the diagnosis of B-cell leukemia was supported by a comprehensive panel of diagnostic evaluations, including cytology, histopathology, immunohistochemistry, and immunophenotyping. This case report highlights the significance of accurate diagnosis and classification of hematologic neoplasia in sheep, emphasizing the need for immunophenotyping to aid in the diagnosis of B-cell leukemia. It also emphasizes the importance of considering spontaneous leukemia as a differential diagnosis in sheep with lymphoid neoplasia, especially in the absence of circulating infectious diseases.