The rapid scientific interest in gut microbiota (GM) has coincided with a global increase in the prevalence of infectious and non-infectivous liver diseases. GM, which is also called “the new virtual metabolic organ”, makes axis with a number of extraintestinal organs, such as kidneys, brain, cardiovascular, and the bone system. The gut-liver axis has attracted greater attention in recent years. GM communication is bi-directional and involves endocrine and immunological mechanisms. In this way, gut-dysbiosis and composition of “ancient” microbiota could be linked to pathogenesis of numerous chronic liver diseases such as chronic hepatitis B (CHB), chronic hepatitis C (CHC), alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), development of liver cirrhosis, and hepatocellular carcinoma (HCC). In this paper, we discuss the current evidence supporting a GM role in the management of different chronic liver diseases and potential new therapeutic GM targets, like fecal transplantation, antibiotics, probiotics, prebiotics, and symbiotics. We conclude that population-level shifts in GM could play a regulatory role in the gut-liver axis and, consequently, etiopathogenesis of chronic liver diseases. This could have a positive impact on future therapeutic strategies.

Introduction: Chronic Hepatitis C Virus (HCV) infection leads to progressive fibrosis making fibrosis staging necessary in the evaluation of such patients. Different fibrosis scores are emerging as possible non-invasive alternatives for liver biopsy. The Fibrosis-4 Index (FIB-4) and AST to Platelet Ratio Index (APRI) scores are the most widely used and the most extensively tested. This study aims to determine if it was possible to accurately use these to identify patients that are unlikely to have severe fibrosis. Methodology: One hundred and forty-two patients with chronic hepatitis C infection who underwent liver biopsy since January 1st 2014 until May 31st 2017 at the Hospital for Infectious and Tropical Diseases in Belgrade were analyzed. The FIB-4 and APRI scores were calculated for each patient and compared to histologically determined fibrosis stage. Results: A comprehensive statistical analysis was conducted in order to compare patients with and without severe fibrosis and to evaluate the accuracy of the fibrosis scores. Patients with non-severe fibrosis were younger, had higher platelet counts and lower transaminase levels. FIB-4 had an AUC of 0.875 and the APRI score had an AUC of 0.861. No patients with severe fibrosis or cirrhosis had a FIB-4 lower than 1.08. FIB-4 was superior to APRI in identifying patients with severe fibrosis in the study cohort. Conclusion: FIB-4 was superior to APRI in the recognition of severe fibrosis. FIB-4 may prove very useful in identifying patients without advanced liver disease, especially if other non-invasive methods are inaccessible.

Helicobacter pylori infection does not belong to the spectrum of opportunistic infections in people living with HIV (PLHIV). To evaluate the Helicobacter pylori infection prevalence rate trends in HIV co-infected individuals in comparison to the HIV-negative population, we compared histopathological findings of H. pylori positive gastritis (gastritis topography and histopathology) between 303 PLHIV and 2642 HIV-negative patients who underwent esophagogastroduodenoscopy (EGD) between 1993 and 2014 due to dyspeptic symptoms. The prevalence of H. pylori infection was significantly higher in HIV-negative controls than in PLHIV (50.2% vs. 28.1%). A significantly positive linear trend of H. pylori co-infection in PLHIV was revealed in the observed period (b = 0.030, SE = 0.011, p = 0.013), while this trend was significantly negative in HIV-negative patients (b = - 0.027, SE = 0.003, p < 0.001). Patients with HIV/H. pylori co-infection had significantly higher CD4+ T cell counts and more often had undetectable HIV viremia, due to successful anti-retroviral therapy (ART). Stomach histopathological findings differed between HIV co-infected and H. pylori mono-infected patients. Our findings confirm that the ART has changed the progression of HIV infection, leading to a significant increase in the prevalence of H. pylori infection in dyspeptic PLHIV over time. Our data also suggests that a functional immune system may be needed for H. pylori-induced human gastric mucosa inflammation.

Introduction: Clostridium difficile infection (CDI) is the most common cause of hospital-acquired diarrhea. Severity of CDI is associated with advanced age and co-morbidities. The clinical spectrum varies from mild watery diarrhea to severe fulminant pseudomembranous colitis with complications. Methodology: This study conducted over a six-year period (2008 to 2013) included 510 patients treated at the University Hospital for Infectious and Tropical Diseases in Belgrade, Serbia. In patients with a history of previous hospitalization and/or treatment with antimicrobial agents who developed diarrhea, the diagnosis was established with rapid tests for C. difficile toxin A and B and by stool culture for C. difficile (454 patients) or by endoscopic examination and histological analyses of the biopsy samples taken from the colonic mucosa (56 patients). Results: The mean age of patients was 67.71± 13.34 years. A total of 67.8% patients were older than 65 years. Over half (58.7%) of the patients were female. 93% had been previously hospitalized and/or had surgical interventions, during which they had been treated with antibiotics. In the clinical presentation spectrum, pseudomembranous colitis occurred in 51.0% .The mean duration of illness after the introduction of specific antibiotic therapy was 7.10 ± 4.88 days. Complications developed in 14 patients. The disease relapsed in 43 (8.4%). Thirty-two (6.3%) patients died, mostly due to co-morbidities. Conclusions: CDI is the most important cause of hospital-acquired diarrhea in Serbia. The disease mainly affects elderly patients with co-morbidities. The incidence of complications is low and prognosis is age dependent and related to pre-existing diseases.

Disseminated fungal infections are still rare conditions, mostly caused by Candida spp. during immunosuppression. Infection of immunocompetent individuals is uncommon. Endocarditis is a rare manifestation during candidaemia, mostly in patients with prosthetic valves. Affection of previously unaltered valves is uncommon. Case presentation We presented a case of a young, previously healthy female patient with endocarditis, caused by Candida parapsilosis. The initial symptom, fever, was present four months before hospital admittance. She was febrile without other symptoms and during observation in a local hospital. After her condition deteriorated, she was transferred to the Institute for infectious and tropical diseases, Belgrade. Clinical findings on admission include petechial skin rash and moderate hepatosplenomegaly. Newly developed systolic murmur was noted, and Candida parapsilosis was isolated in multiple blood cultures. Echocardiography revealed 15 × 14 mm vegetations on the right aortic vellum. She was treated with antifungal drugs (fluconasole, liposomal amphotericin B), and the affected valve was successfully replaced. The same strain of Candida parapsilosis was isolated from the intraoperative material of the valve. There were no markers of immunosuppression or other conditions which could affect the immune system. Conclusion After a prolonged period of treatment she was successfully cured, and she received a long-term intermittent suppressive fluconasole therapy for the time being.