Impact of the COVID-19 pandemic on the treatment of acute cholangitis caused by choledocholithiasis: A single-center retrospective study in Japan

Objectives

This study aimed to determine the impact of the coronavirus disease 2019 (COVID-19) pandemic on the treatment of acute cholangitis caused by choledocholithiasis.

Methods

The Japanese government declared a state of emergency in April 2020 due to the COVID-19 pandemic. We retrospectively reviewed the medical records of 309 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) for acute cholangitis caused by choledocholithiasis between April 2017 and December 2022.

Results

Patients were categorized into a pregroup (n = 134) and a postgroup (n = 175), depending on whether they were diagnosed before or after the state of emergency declaration. The total number of ERCP cases and the number of ERCP cases with endoscopic stone removals increased after the state of emergency declaration. Compared with the pregroup, the numbers of patients with performance status of 0-1 and surgically altered anatomy increased, whereas the numbers of patients taking oral antiplatelets or anticoagulants and those with cerebrovascular disease decreased in the postgroup. The number of single-stage endoscopic stone removals increased and hospital stays were significantly shorter in the postgroup. No differences in adverse event rates were detected between the two groups.

Conclusions

Although our hospital provides tertiary care, the number of patients with cholangitis in good general condition and no underlying disease increased after the state of emergency declaration. The COVID-19 pandemic resulted in an increase in the number of single-stage endoscopic treatments and shortened hospital stays for patients with acute cholangitis caused by choledocholithiasis. No safety issues with ERCP were detected, even during the pandemic.

Methotrexate-associated lymphoproliferative disorder: A rare pancreatic tumor diagnosed via endoscopic ultrasound-guided fine-needle biopsy

A 73-year-old woman with a history of rheumatoid arthritis treated with methotrexate (MTX) for the last 10 years was referred to our hospital for a pancreatic tumor examination. Contrast-enhanced abdominal computed tomography revealed a 20-mm-diameter hypovascular tumor in the pancreatic tail. A hypoechoic mass with heterogeneous internal echo was found on an endoscopic ultrasound (EUS). An EUS-guided fine-needle biopsy (EUS-FNB) was performed with a 22-gauge Franseen-tip needle. Histologic examination of EUS-FNB specimens from the pancreatic tumor revealed the proliferation of atypical spindle cells. Immunohistochemical staining for CD20 and Ki-67 was positive in the atypical cells. Immunohistochemical staining for CD3 was partially positive in the atypical cells. Epstein-Barr virus-encoded RNA in situ hybridization showed positive staining. MTX-related lymphoproliferative disorder (MTX-LPD) with Epstein-Barr virus infection was diagnosed. MTX treatment was immediately discontinued, and treatment was initiated by a hematologist. However, her condition rapidly deteriorated, and she died of multiple organ failure 4 weeks after diagnosis. MTX-LPD can complicate gastrointestinal lesions. However, most lesions are localized in the stomach and rarely complicate pancreatic lesions. MTX-LPD is classified as an "iatrogenic" LPD. Therefore, immediate action, such as MTX discontinuation, is necessary. In conclusion, endoscopists should be aware that MTX-LPD lesions can occur in the pancreas and gastrointestinal tract. Moreover, EUS-FNB can be useful in the diagnosis of this rare pancreatic tumor.

Spatial structure of electric potential near the extraction region in Cs-seeded H(-) ion sources

Structure of electric potential near the extraction region in a negative ion source is investigated analytically with the effect of strong surface H(-) production. The potential profile is analyzed one dimensional by solving the plasma-sheath equation, which gives the electric potential in the plasma region and the sheath region near the wall self-consistently. The potential profile depends on the production rate and the temperature of negative ions. As the production rate becomes large and the negative ion energy becomes small, the potential near the extraction region decreases. The negative potential peak is formed near the plasma grid (PG) surface for the case of large amount and low energy surface production. As a result, negative ions are reflected by this negative potential peak near the PG and returned to the PG surface. This reflection mechanism by the negative potential peak possibly affects the negative ion extraction.