Volume 03 · Issue 03 · 2023

Non-alcoholic fatty liver disease (NAFLD) has become the world’s largest chronic liver disease in the 21st century, affecting 20%-30% of the world’s population. As the epidemiology, etiology, and pathogenesis of NAFLD have been studied in-depth, it has been gradually recognized that most patients with NAFLD have one or more combined metabolic abnormalities known as metabolic syndrome. In 2020, the international expert group changed the name of NAFLD to metabolic-associated fatty liver disease (MAFLD) and proposed new diagnostic criteria for MAFLD and MAFLD-related liver cirrhosis, as well as the conceptual framework of other cause-related fatty liver diseases to avoid diagnosis based on the exclusion of other causes and better reflect its pathogenesis. However, there are still many ambiguities in the term, and changing the name does not address the unmet key needs in the field. The change from NAFLD to MAFLD was not just a change of definition. The problems and challenges are summarized as follows: epidemiology, children, rationality of "metabolism," diagnostic criteria, double/multiple causes, drug discovery, clinical trials, and awareness raising. Metabolic-associated fatty liver disease has complex disease characteristics, and there are still some problems that need to be solved.

A recent study revealed that the inhibition of the farnesoid X receptor using ursodeoxycholic acid (UDCA) significantly reduces angiotensin-converting enzyme 2 (ACE2) expression. Therefore, considerable attention has been paid to the use of UDCA to prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and reduce the severity of the disease. This review comprehensively summarizes the role of ACE2 in SARS-CoV-2 infection and the potential role and mechanisms of UDCA in the prevention of SARS-CoV-2 infection or reinfection. It also discusses unresolved issues and the potential use of UDCA in the treatment of patients with coronavirus disease.

Patients with chronic liver diseases (CLDs) have high hospitalization and mortality rates when combined with severe coronavirus disease 2019 (COVID-19) because of defects in humoral and cellular immunity, known as immune dysfunction. COVID-19 vaccines effectively reduce the risk of severe illness and mortality caused by the virus. Several studies have confirmed the safety and efficacy of the COVID-19 vaccine in patients with CLD, and the existing expert consensus recommends that patients with stable CLD be prioritized for the COVID-19 vaccine. In addition, clinical trials are ongoing to determine the optimal strategy for patients with CLD to receive the COVID-19 vaccine. In this study, we review the progress of research on the safety and efficacy of COVID-19 vaccination in patients with CLD, aiming to provide better recommendations for the vaccination in this population.

In this study, we aimed to explore the safety and vaccination coverage data of Chinese patients with breast cancer receiving coronavirus disease 2019 (COVID-19) vaccination. The patients were recruited from 41 hospitals across 20 Chinese provinces. The vaccination coverage was approximately 22.4%, and the frequency of total adverse events was 13.3% after the first dose and 9.9% after the second dose. The most frequent adverse reaction within 14 days of the first dose was local pain (5.7%). Unvaccinated patients were very likely to reject the vaccine rather than be hesitant in patients with old age (odds ratio [OR], 1.238; 95% confidence interval [CI], 1.101-1.391), chronic disease history (OR, 1.189; 95% CI, 1.057-1.337), and cancer relapse (OR, 1.398; 95% CI, 1.233-1.585). Of the unvaccinated patients with breast cancer, 54.1% opted to receive COVID-19 vaccines if more data were available. Considering the safety but low vaccination coverage for breast cancer, increased positive attitudes and acceptance toward COVID-19 vaccines are important.

Parvovirus B19 (B19V) infection can cause pure red cell aplasia (PRCA) in patients with human immunodeficiency virus (HIV) infection. Intravenous immunoglobulin (IVIG) is a preferred treatment option. From July 2019 to March 2022, four patients with HIV infection were admitted to Guangzhou Eighth People’s Hospital with dizziness and fatigue and were diagnosed with PRCA. Blood investigations revealed severe anemia and the B19V genome. Therefore, the four patients were diagnosed with B19V-induced PRCA. All four patients received red blood cell transfusion in the setting of antiretroviral therapy, and two of the four patients received intravenous immunoglobulin (IVIG). After 3-7 months of treatment, all four patients recovered, although two did not receive IVIG. This suggests that IVIG is not always necessary for the treatment of PRCA in patients with HIV infection and that effective antiretroviral therapy and immunological reconstitution play an important role in the eradication of parvovirus.

Microbiological diagnosis of chronic osteoarticular infections remains a major challenge, particularly when the clinical presentation is atypical and the pathogen is uncommon. In this unique case, Capnocytophaga canimorsus, a microorganism belonging to the oral microbiota of some domestic animals, caused septic arthritis and multifocal osteomyelitis in the long bone of a 43-year-old immunocompetent man. The patient was treated with two-stage surgery and local and systemic antibiotic therapy, and had a successful recovery. C. canimorsus should be considered as a possible etiological agent in patients with osteoarticular pathology and a history of exposure to domestic animals.

A rare case of occult cytomegalovirus (CMV) cholangitis along with an updated literature review is presented. The patient had not undergone solid organ-bone marrow transplantation and had no chronic autoimmune biliary tract disorder or obvious immunodeficiency.The patient had underwent a pyloric-sparing duodenocephalopancreasectomy, and the postoperative histopathologic examination revealed multiple ulcerative lesions and an occult CMV infection. The copy number of CMV DNA was high (38,000 copies/μg DNA) in common bile duct surgical specimens measured by real-time quantitative polymerase chain reaction. CMV was not detected in blood and urine samples from the patient after full doses of intravenous ganciclovir and full doses of oral valganciclovir antiviral therapy. This report recapitulates the role of CMV in causing severe cholangiopathy in the absence of obvious immunosuppression or autoimmune disorder of the biliary tract.

Human intestinal spirochetosis is a rare clinicopathological condition characterized by the presence of spirochetal microorganisms on the surface of the colorectal mucosa and, in some cases, by their invasion into the lamina propria. The most frequent cause of this infection is immunocompromised status. Our case report describes a patient with relevant symptoms and endoscopic alterations, but limited invasion by spirochetes, as shown by histological analysis of ileal and colonic specimens. After histological examination, metronidazole was initiated. This resulted in rapid and complete resolution of the symptoms, which demonstrated an infectious etiology. The peculiarity of our case is that the clinical and endoscopic appearances were typical of the aggressive behavior of the disease, but histological samples showed only superficial colonization of the colonic epithelium without clear invasion of deeper layers. This case report emphasizes that the virulence of spirochetes is not strictly related to intestinal mucosal invasion.

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