General dynamics of the URT microbiome and microbial signs of recovery in COVID-19 patients.

COVID-19 is caused by an airborne virus, SARS-CoV-2. The upper respiratory tract (URT) is, therefore, the first system to endure the attack. Inhabited by an assemblage of microbial communities, a healthy URT wards off the invasion. However, once invaded, it becomes destabilised, which could be crucial to the establishment and progression of the infection. We examined 696 URT samples collected from 285 COVID-19 patients at three time-points throughout their hospital stay and 100 URT samples from 100 healthy controls. We used 16S ribosomal RNA sequencing to evaluate the abundance of various bacterial taxa, α-diversity, and ß-diversity of the URT microbiome. Ordinary least squares regression was used to establish associations between the variables, with age, sex, and antibiotics as covariates. The URT microbiome in the COVID-19 patients was distinctively different from that of healthy controls. In COVID-19 patients, the abundance of 16 genera was significantly reduced. A total of 47 genera were specific to patients, whereas only 2 were unique to controls. The URT samples collected at admission differed more from the control than from the samples collected at later stages of treatment. The following four genera originally depleted in the patients grew significantly by the end of treatment: Fusobacterium, Haemophilus, Neisseria, and Stenotrophomonas. Our findings strongly suggest that SARS-CoV-2 caused significant changes in the URT microbiome, including the emergence of numerous atypical taxa. These findings may indicate increased instability of the URT microbiome in COVID-19 patients. In the course of the treatment, the microbial composition of the URT of COVID-19 patients tended toward that of controls. These microbial changes may be interpreted as markers of recovery.

[Integration of ICG-fluorescence cholangiography into the safety system of laparoscopic cholecystectomy]. / Integratsiya ICG-fluorestsentnoi kholangiografii v sistemu bezopasnosti laparoskopicheskoi kholetsistektomii.

THE AIM OF THE STUDY: Is evaluating the possibility of integrating ICG-fluorescent cholangiography into the general safety system for laparoscopic cholecystectomy to prevent damage to the extrahepatic bile ducts by working out the methodological aspects of navigation technologies. MATERIALS AND METHODS: The analysis of literature data on various approaches to improve the perioperative identification of anatomical structures during laparoscopic cholecystectomy, including the ICG-fluorescent cholangiography, was carried out. This program was implemented during the provision of elective surgical care to 24 patients with cholelithiasis who underwent laparoscopic cholecystectomy with ICG-fluorescent navigation. RESULTS AND DISCUSSION: The developed program included: preoperative assessment of the anatomy of the biliary tree using MRCP; intraoperative technique of safe laparoscopic cholecystectomy with mandatory application of the concept of «critical view of safety¼ (CVS), which allows the most effective identification of the necessary anatomical structures; the use of ICG-fluorescent cholangiography, which allows to improve the control of anatomical structures at all stages of the operations. CONCLUSIONS: The first experience of using ICG-fluorescent cholangiography testifies to the high informative value of the method, the possibility and prospects of integrating the technology into a comprehensive safety system during laparoscopic cholecystectomy.