To evaluate the efficacy of computed tomography (CT) lymphangiography after direct mesenteric lymph node injection for thoracic duct (TD) visualization in mice.

Twelve female BALB/c mice were injected with 35 μL of iodinated contrast medium (iomeprol 350 mgI/mL) into the mesenteric (mesenteric group) or popliteal (popliteal group) lymph nodes. CT images were acquired before injection and 1 min, 3 min, 5 min, 10 min, and 15 min after injection using a micro-CT scanner. Contrast ratios (CRs) were measured at the cisterna chyli and three levels of the TD (diaphragm, carina, and venous angle). Two experienced radiologists qualitatively assessed images as good, fair, or poor.

The mesenteric group had significantly higher mean (± standard deviation) CRs than the popliteal group for all examined regions at 1 min after injection: cisterna chyli (14.01 ± 4.77 versus 1.47 ± 1.21, p < 0.001), diaphragm (7.28 ± 2.50 versus 0.85 ± 0.61, p = 0.0011), carina (10.33 ± 3.42 versus 0.44 ± 0.40, p < 0.001), and venous angle (6.26 ± 2.02 versus 0.79 ± 0.75, p < 0.001). For the TD between the cisterna chyli and the diaphragm, 6/6 mice in the mesenteric group showed strong enhancement, whereas 5/6 mice in the popliteal group showed minimal or no enhancement. The visual scores of the mesenteric group were significantly higher than those of the popliteal group for all the evaluated regions (p = 0.002).

CT lymphangiography via mesenteric lymph node injection provides better imaging of the TD in mice than popliteal lymph node injection.

This study enhances TD visualization in mice, advancing preclinical research on lymphatic disorders and improving translational applications for better clinical diagnostics and treatments.

Mesenteric lymph node injection improved the efficacy of TD CT lymphangiography in mice. Mesenteric injection provided significantly better TD visualization than popliteal injection. Enhanced TD visualization in mice advances preclinical research on lymphatic diseases.

Tuberculosis is a global epidemic infection that typically presents with symptoms affecting the respiratory system. Abdominal tuberculosis is an uncommon manifestation, occurring in only 5% of tuberculosis cases globally and can present with a broad range of vague symptoms that mimic other biliary and pancreatic pathologies. We report a case of a 36-year-old woman presenting with jaundice and biliary obstruction secondary to abdominal tuberculosis. Computed tomography and magnetic resonance cholangiopancreatography revealed a loculated retroperitoneal mass abutting the pancreatic head and duodenum with associated common bile duct dilatation. Endoscopic ultrasound demonstrated an ulcerated mass in the duodenum which was biopsied. Necrotising granulomas were identified on histology and the biopsied tissue was positive on tuberculosis polymerase chain reaction testing. Thus, extrapulmonary abdominal tuberculosis was diagnosed. The patient was commenced on a 6-month course of rifampicin, isoniazid, pyrazinamide and ethambutol treatment and demonstrated complete response to medical therapy. Abdominal tuberculosis can be difficult to diagnose but should remain an important differential to be considered for patients with previous travel or residence in endemic areas presenting with gastrointestinal symptoms. Prompt diagnosis and treatment can prevent unnecessary procedures, complications and death in patients with biliary obstruction caused by abdominal tuberculosis.

In this editorial, we comment on the article by Ali et al published in the recent issue of the World Journal of Clinical Cases. This case report shed light on a particularly rare manifestation of this disease-primary gastrointestinal tuberculosis (GTB) presenting as gastric outlet obstruction. GTB presents diagnostic challenges due to its nonspecific symptoms and lack of highly accurate diagnostic algorithms. This editorial synthesizes epidemiological data, risk factors, pathogenesis, clinical presentations, diagnostic methods, and therapies to raise awareness about GTB. GTB constitutes 1%-3% of all tuberculosis cases globally, with 6%-38% of patients also having pulmonary tuberculosis. Pathogenesis involves various modes of Mycobacterium tuberculosis complex entry into the gastrointestinal system, with the terminal ileum and ileocecal valve commonly affected. Clinical presentation varies, often resembling other intra-abdominal pathologies, necessitating a high index of suspicion. Diagnostic tools include a combination of biochemical, microbiological, radiological, and endoscopic assessments. Anti-tubercular medication remains the cornerstone of treatment, supplemented by surgical intervention in severe cases. Multidisciplinary management involving gastroenterologists, surgeons, pulmonologists, and infectious disease specialists is crucial for optimal outcomes. Despite advancements, timely diagnosis and management challenges persist, underscoring the need for continued research and collaboration in addressing primary GTB.

Pancreatobiliary lymphadenopathy (PBL) may be due to a number of benign or malignant causes. Tissue sampling of these lymph nodes (LN) can be possible with the help of endoscopic ultrasound (EUS). Aim of this study was to identify the etiology of the PBL, morphology, and factors predicting good yield of biopsy with EUS.

All patients found to have pancreatobiliary lymph node (PBLN) enlargement (>10 mm) on abdominal imaging and referred for EUS-guided biopsy were included in this prospective observational study. The facility of rapid on-site evaluation (ROSE) was not available. Adequacy of the tissue specimen was assessed by the endoscopist with macroscopic on-site evaluation (MOSE) and then sent to histopathologist for final diagnosis. Factors predicting good yield of biopsy were then analyzed.

Of the total 87 patients with PBL, 54 (62.1%) were males. Mean age of the patients was 52.0 (±13.4) and range 18-80 years. The commonest locations of PBL were porta hepatis 37 (42.5%), peripancreatic 24 (27.6%), celiac 16 (18.4%), and others 10 (11.5%). Histological reports showed: neoplastic tissue in 34 (39.1%), non-neoplastic in 20 (23%), normal lymphoid tissue (27.6%) and suboptimal in 9 (10.3%). Among the 34 neoplastic causes, 26 had metastatic adenocarcinoma, 5 had lymphoma, and 3 had metastatic neuroendocrine tumors. Among the 20 non-neoplastic causes, 10 had tuberculosis, 4 had anthracosis, and 6 had other findings. Factors predicting good yield of biopsy were a PBLN size ≥12 mm and satisfactory MOSE on both univariate [PBLN (p = 0.005); MOSE (p < 0.0001)] and multivariate [PBLN (p = 0.011); MOSE (p < 0.0001)] analysis.

The commonest etiology of PBLN enlargement was metastatic adenocarcinoma among the neoplastic causes and tuberculosis among the non-neoplastic causes. The most common PBLNs approached by EUS were in portahepatis and peripancreatic regions. A good biopsy yield can be predicted with PBLN size of ≥12 mm and a satisfactory MOSE.

Tasneem AA, Yaseen T, Laeeq SM, et al. Pancreatobiliary Lymphadenopathy: Etiology, Location, and Factors Predicting Good Yield of Endoscopic Ultrasound-guided Biopsy. Euroasian J Hepato-Gastroenterol 2024;14(1):40-43.

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an established method for the evaluation of abdominal organ lesions. However, there are few studies on EUS-FNA for abdominal lymph node (LN) lesions. The purpose of this study was to evaluate the diagnostic role of EUS-FNA in isolated abdominal lymphadenopathy (LAP).

A retrospective analysis was performed on patients with isolated abdominal LAP who underwent a EUS-FNA examination. The diagnosis was made based on cytology, histology, and immunohistochemical (IHC) studies. The area under curve (AUC) value, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated.

A total of 99 patients were included in this study. The final diagnoses were metastatic tumor (n = 32), lymphoma (n = 32), tuberculosis (n = 17), sarcoidosis (n = 5), castleman's disease (n = 1), and reactive LAP (n = 12). The AUC value, sensitivity, specificity, PPV, NPV, and accuracy of EUS-FNA in the diagnosis of malignant LAP were 0.9531, 90.6, 100, 100, 85.4, and 93.9%, respectively. For the diagnosis of lymphoma, the accuracy of EUS-FNA combined with IHC staining was 94.9%. Retroperitoneal LN enlargement is more commonly associated with lymphoma, while hepatic hilar LN enlargement predominantly suggests benign conditions or metastatic tumors. Malignant lymph nodes are more likely to be regular border, circular/quasi-circular, and fusion. Lymphomas are more likely to present with fusion and heterogeneous echogenicity than metastatic tumors.

EUS-FNA is a safe and effective method to diagnose isolated abdominal LAP.

Peripancreatic tuberculous lymphadenopathy can mimic pancreatic cancer on imaging. There have only a few reports on varices from portal vein obstruction due to abdominal tuberculous lymphadenopathy. Iatrogenic disseminated tuberculosis is also rare. Herein, we present a rare case of peripancreatic tuberculous lymphadenopathy with ruptured duodenal varices due to portal vein obstruction. The patient presented to our hospital with hematemesis. Computed tomography revealed a peripancreatic mass. Duodenal varices rupture from portal vein obstruction due to pancreatic cancer were initially suspected. The patient underwent portal vein stenting for portal vein obstruction and endoscopic ultrasound-guided fine-needle aspiration for diagnosis, which revealed granulomas indicative of tuberculosis. The patient was discharged once because fine-needle aspiration did not lead to a definitive diagnosis of tuberculosis. Subsequently, he developed disseminated tuberculosis. Peripancreatic tuberculous lymphadenopathy can cause ectopic varices with portal vein obstruction. Tuberculosis should also be included in the differential diagnosis in the case of portal vein obstruction, to facilitate early treatment and avoid unnecessary surgery. Furthermore, fine-needle aspiration or portal vein stenting for tuberculous lesions can cause disseminated tuberculosis. Since a diagnosis might not be made until after several fine-needle aspirations have been conducted, careful follow-up is necessary after the procedure for such lesions.