Endoscopic ultrasound-guided fine needle aspiration: The wet suction technique

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has become a fundamental tool in obtaining cytopathological diagnosis of pancreatic tumors. When sampling solid lesions of the pancreas, the endosonographer can use two suction techniques to enhance tissue acquisition; the dry and the wet suction techniques. The standard dry suction technique relies on applying negative pressure suction on the proximal end of the needle after the stylet is removed with a pre-vacuum syringe. The wet suction technique relies on pre-flushing the needle with saline to replace the column of air with fluid followed by aspiration the proximal end by using a prefilled syringe with saline. A new modified wet suction technique (hybrid suction technique) relies on preloading the needle with saline, but having continuous negative pressure with a pre-vacuum syringe to avoid manual intermittent suction. Tissue acquisition can be enhanced by applying fluid dynamic principles to the current aspiration techniques, such as the column of water used in the needle of the wet technique. In this review, we will focus on EUS-FNA using the wet suction technique for sampling of pancreatic solid lesions.

Metastatic Fibrolamellar Hepatocellular Carcinoma to the Pancreas

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a rare variant of hepatocellular carcinoma, usually presenting in the younger population (<40 years) without underlying liver disease. Although it has a better prognosis than hepatocellular carcinoma, it has a high rate of recurrence months to years after primary resection. While sites of recurrence usually involve the liver, regional lymph nodes, peritoneum, and lung, metastasis to the pancreas is extremely rare, with only 2 other cases reported in the literature. We present the case of a 46-year-old patient with metastatic FL-HCC to the pancreas 30 years after diagnosis and 26 years since his last resected liver recurrence.

Management of Biliary Strictures After Liver Transplantation

Strictures of the bile duct are a well-recognized complication of liver transplant and account for more than 50% of all biliary complications after deceased donor liver transplant and living donor liver transplant. Biliary strictures that develop after transplant are classified as anastomotic strictures or nonanastomotic strictures, depending on their location in the bile duct. The incidence, etiology, natural history, and response to therapy of the 2 types vary greatly, so their distinction is clinically important. The imaging modality of choice for the diagnosis of biliary strictures is magnetic resonance cholangiopancreatography because of its high rate of diagnostic accuracy and limited risk of complications. Biliary strictures that develop after liver transplant may be managed with endoscopic retrograde cholangiography (ERC), percutaneous transhepatic cholangiography (PTC), or surgical revision, including retransplant. The initial treatment of choice for these strictures is ERC with progressive balloon dilation and the placement of increasing numbers of plastic stents. PTC and surgery are generally reserved for failures of endoscopic therapy or for anatomic variants that are not suitable for ERC. In this article, we discuss the classification of biliary strictures, their diagnosis, and the therapeutic strategies that can be used to manage these common complications of liver transplant.

Campylobacter jejuni is not an important pathogen as a cause of diarrhea in US travelers to Mexico

Campylobacter jejuni is an unusual cause of travelers' diarrhea acquired in Mexico, but previous studies have relied only on stool culture for diagnosis. We conducted a cohort study to determine if antibody seroconversion to C jejuni would better reflect the occurrence of infection acquired in Mexico. Serum IgG, IgA, and IgM antibodies to Campylobacter seroconverted in only 2 of 353 participants (0.6%). These data further support that C jejuni infection is an unusual cause of travelers' diarrhea in US visitors to Mexico.

Enterotoxigenic Escherichia coli heat-labile toxin seroconversion in US travelers to Mexico

BACKGROUND AND AIMS

Enterotoxigenic Escherichia coli (ETEC) is the most common bacterial pathogen isolated from travelers suffering of diarrhea. Exposure to heat-labile toxin (LT) produces a high rate of seroconversion. However, the role of LT-producing ETEC (LT-ETEC) as a cause of diarrhea is controversial. We conducted a cohort study in US students traveling to Mexico to assess the ETEC-LT seroconversion rate after natural exposure.

METHODS

Participants provided a serum sample on arrival and departure and a stool sample when ill. ETEC-LT immunoglobulin G antibodies were measured by enzyme-linked immunosorbent assay, and LT-ETEC were detected by means of polymerase chain reaction done on fecal DNA.

RESULTS

A total of 422 participants with a mean age of 34.5 years were followed a mean of 19.9 days; 304 were females (72.0%), and 319 (75.6%) traveled during the summer months. In total, 177 individuals (41.9%) developed travelers' diarrhea and 33.9% had LT-ETEC identified in their stools. Among individuals having an LT-ETEC strain, 74% seroconverted compared to 11% of those not having diarrhea (p < 0.0001). When analyzed with a logistic regression model, the odds of seroconversion were significantly reduced in participants not having LT-ETEC in their stool (odds ratio = 0.1, p < 0.0001) after adjusting for season, length of stay, age, gender, race, and ethnicity.

CONCLUSION

In US young adults traveling to Mexico, ETEC-LT seroconversion reliably identifies individuals naturally exposed to ETEC and correlates with symptomatic illness, length and season of travel.