Ancylostoma caninum, the canine hookworm, is the most common and clinically important gastrointestinal nematode parasite infecting dogs in the US. Common clinical signs associated with acute infections include anemia, melena, hematochezia, dehydration, and poor weight gain or weight loss. In the past few years, multiple anthelmintic drug resistance to fenbendazole, moxidectin, and pyrantel pamoate has been documented in A caninum in the US, and cases of drug-resistant canine hookworms are increasingly being reported in the US and Canada. Clinical and genetic evidence strongly suggests that multiple anthelmintic drug-resistant A caninum likely originated on Greyhound breeding farms and kennels. However, the problem is no longer restricted to Greyhounds; several large national studies have shown that drug-resistant A caninum was present in dogs of all sizes, ages, and breeds and at varying but always high prevalence in every region of the continental US. The high prevalence and wide distribution of drug-resistant hookworms present a matter of urgent concern for veterinarians in North America and elsewhere. In response to this concern, the American Association of Veterinary Parasitologists established a Hookworm Task Force in 2021, and this paper is a result of the work of that task force. Here we provide guidance on best practices for diagnosis, treatment, and management of drug-resistant hookworm cases and summarize relevant studies to help veterinarians understand what is known about the biology, prevalence, and epidemiology of these parasites.

Hereditary hemorrhagic telangiectasia (HHT) is a genetic disorder of the vasculature associated with mucocutaneous telangiectasia and visceral arteriovenous malformations (AVMs). These manifestations can frequently lead to chronic blood loss and iron deficiency anemia. In some cases, anemia can be severe and transfusion-dependent, reflecting an advanced disease phenotype with persistent vascular involvement and cumulative blood loss. This report presents a case of a 58-year-old female with a known diagnosis of HHT who presented with fatigue, dizziness, and chronic melena, and was found to have a hemoglobin level of 4.7 g/dL. Imaging revealed persistent pulmonary AVM disease, which may increase cardiopulmonary demand, particularly in the setting of severe anemia, and may contribute to complications if left untreated. The patient required transfusion of five units of packed red blood cells and underwent endoscopic ablation of multiple telangiectasias in the stomach and duodenum. This case underscores the persistent nature of HHT-related gastrointestinal bleeding and the cardiopulmonary consequences of multi-system AVM burden. It emphasizes the necessity for multidisciplinary care and ongoing surveillance in patients with HHT to prevent symptom progression.

Glanzmann thrombasthenia (GT) is a rare autosomal recessive bleeding disorder from defects in the αIIbβ3 integrin receptor, impairing platelet aggregation and often overlooked due to normal platelet counts. Juvenile polyposis syndrome (JPS) is an autosomal dominant disorder with multiple gastrointestinal polyps and increased colorectal cancer risk. Their co-occurrence is exceedingly rare and challenging. We report a 19-year-old male who was diagnosed with GT at age 5 after rectal bleeding from a gastrointestinal polyp requiring polypectomy and transfusions; platelet aggregation studies confirmed GT. At age 9, genetic testing established JPS. In 2014 he developed recurrent severe bleeding-hematochezia, melena, and hemarthrosis-managed with recombinant activated factor VII (rFVIIa), blood transfusions, and supportive care including vitamin D. Additional findings included duodenal lymphangioma requiring resection, vitamin D deficiency with bone pain and complex regional pain syndrome, and chronic idiopathic hypertension treated with antihypertensives. This case highlights rFVIIa effectiveness and the need for multidisciplinary, long-term follow-up and care.

We report a case of a patient presenting with melena and dysphagia. His gastroscopy revealed an oesophageal mass and active duodenal papillary haemorrhage. Subsequent endoscopic retrograde cholangiopancreatography (ERCP) confirmed the presence of a haemorrhagic mediastinal pancreatic pseudocyst (MPP). Due to severe alcohol withdrawal syndrome, the patient declined surgical intervention. Conservative management and pancreatic tube placement under ERCP were performed, resulting in clinical stabilization. Follow-up imaging 2 months later demonstrated partial remission of the MPP. We further review the clinical characteristics and contemporary management strategies for MPP.

Aortic fistulas are rare but life-threatening vascular abnormalities characterized by abnormal communication between the aorta and an adjacent structure secondary to weakening of the vessel wall, such as in the setting of atherosclerosis or prior surgical intervention. Aortic fistulas can arise anywhere along the course of the aorta, with aortoenteric fistula being the most common type. Clinical presentation varies depending on the fistula type but often includes haemorrhagic symptoms such as hypotension, haematemesis, haematuria, and melena. Haemorrhagic shock and sepsis are common and often fatal complications. Prompt diagnosis is critical to reduce morbidity and mortality, and radiology plays a key role in diagnosis. CT angiography is the preferred imaging modality due to its rapid image acquisition and high spatial resolution. Radiologists must be able to recognize direct and indirect signs of aortic fistulas. In addition, differentiating aortic fistulas from mimics such as perigraft infection and inflammatory aortitis is essential for appropriate management.

Downhill esophageal varices, an uncommon etiology of upper gastrointestinal bleeding, arise from superior vena cava obstruction rather than portal hypertension. Etiologies include malignancy, intravascular devices, and dialysis-related central venous stenosis. A 79-year-old man with end-stage renal disease on hemodialysis presented with melena and hematemesis. Endoscopy revealed large proximal esophageal varices; imaging showed chronic superior vena cava stenosis related to his indwelling dialysis catheter. Endoscopic band ligation followed by balloon venoplasty achieved hemostasis and endovascular patency. This case illustrates downhill variceal bleeding as a sequela of hemodialysis catheter associated superior vena cava stenosis and emphasizes the significance of timely identification and management.

Gastric hyperplastic polyps can cause gastrointestinal bleeding, and their enlargement has been associated with long-term acid-suppressive therapy. Vonoprazan (VPZ), a potassium-competitive acid blocker, provides potent acid suppression and may induce hypergastrinemia, potentially contributing to the growth of hyperplastic polyps. However, clinical information regarding VPZ-associated gastric hyperplastic polyps remains limited. We report three cases of severe bleeding from gastric hyperplastic polyps in patients who were administered VPZ. Case 1 involved a 92-year-old woman who presented with melena and anemia. Endoscopy revealed an 8-cm hyperplastic polyp, and although resection was considered, it was deferred. After switching from VPZ to an H2-receptor antagonist (H2RA), her anemia gradually improved, and the polyp regressed. Case 2 involved a 61-year-old man with hematemesis due to bleeding from multiple hyperplastic polyps. Emergency endoscopic mucosal resection was performed, and markedly elevated serum gastrin levels were noted. Following the replacement of VPZ with an H2RA, the size of the remaining polyps decreased. Case 3 involved a 54-year-old man with anemia and recurrent bleeding from hyperplastic polyps, requiring multiple endoscopic treatments. After VPZ discontinuation and H2RA initiation, the unresected polyps regressed. Two patients were undergoing hemodialysis, which may have exacerbated hypergastrinemia and bleeding. In all three cases, switching from VPZ to an H2RA resulted in the regression of gastric hyperplastic polyps and improvement of anemia. In patients receiving VPZ who develop progressive anemia or bleeding from hyperplastic polyps, discontinuation of VPZ or switching to an H2RA may be effective.

Endovascular aneurysm repair (EVAR) is a treatment method that has become increasingly popular for abdominal aortic aneurysms (AAA) due to its ease of application, reduced hospital stay, and its suitability as an alternative for patients who cannot tolerate open surgery. Although the early outcomes of EVAR are better than those of open surgery, complications such as endoleak, migration, thrombosis or kinking of the endograft limbs, graft infection, and secondary rupture may occur. In this study, we present a patient who underwent EVAR at another institution approximately 10 years earlier and was admitted to our clinic with complaints of deterioration in general condition, fever, and melena. Laboratory examination of 73-year-old man revealed a white blood cell (WBC) count of 17,100, hemoglobin level of 9.5 g/dL, and C-reactive protein (CRP) level of 261 g/L. Computed tomography (CT) revealed thrombosis within the EVAR graft, free air surrounding the graft, fractures in the graft stents, and displacement of the right limb beyond the aorta at the level of the iliac bifurcation. The endograft was observed to have migrated toward the duodenum and formed a fistula. The pa-tient, who presented with sepsis, underwent emergency surgery. Initially, a left axillofemoral bypass was performed to relieve ischemia in the left leg. Subsequently, a laparotomy was performed with the joint participation of the general surgery and cardiovascular surgery departments. Intra-abdominal fecal contamination and rupture of the sigmoid colon were observed. The abdomen was lavaged, the sigmoid colon and rectum were excised, and a colostomy was created. An aortotomy was then performed, and the main body of the graft and its left limb were removed. The duodenum was opened, and the fistulized right limb of the endograft was also removed. No additional vascular intervention was required due to abdominal contamination, adequate collateral circulation in the right leg, likely due to the chronic nature of the process, and the absence of ischemia. The aorta was ligated at the infrarenal level, and the patient, who required high-dose inotropic support, was transferred to the intensive care unit. The patient died in the eighth postoperative hour. To our knowledge, this case represents a rare and unique complication that has not been previously reported in the literature. By presenting this case, we aim to draw attention to the long-term complications of EVAR and emphasize the importance of open surgery in patients with a high life expectancy.

Hemosuccus pancreaticus is an uncommon cause of upper gastrointestinal bleeding characterized by hemorrhage entering the pancreatic duct and draining into the duodenum. Although pseudoaneurysms may arise from several peripancreatic vessels in the setting of chronic pancreatitis, involvement of the inferior pancreaticoduodenal artery (IPDA) is particularly uncommon and carries a high risk of rupture. A man in his late 30s with a known history of chronic calcific pancreatitis presented with melena, severe anemia, and hemodynamic instability. Side-viewing duodenoscopy revealed intermittent bleeding from the ampulla of Vater, raising suspicion for hemosuccus pancreaticus. Computed tomography angiography identified a 6.4 cm IPDA pseudoaneurysm causing multi-organ compression. Successful endovascular coil embolization achieved complete occlusion of the pseudoaneurysm. This case demonstrates successful minimally invasive management and diagnostic challenges of a life-threatening vascular complication of chronic pancreatitis. High clinical suspicion, early targeted imaging, and prompt intervention are essential for preventing catastrophic hemorrhage.