Tomasz Dzieciatkowski

Fecal Microbiota Transplantation in Patients With Blood Disorders Inhibits Gut Colonization With Antibiotic-Resistant Bacteria: Results of a Prospective, Single-Center Study

Background Patients with blood disorders colonized with antibiotic-resistant bacteria (ARB) are prone to systemic infections that are difficult to treat. Reintroduction of commensal bacteria in a murine model of enterococcal colonization of the gut can lead to eradication of enterococci. We hypothesized that fecal microbiota transplantation (FMT) could be used to eradicate ARB in humans. Methods Participants colonized with ARB were treated with intraduodenal FMT according to a prospective protocol (NCT02461199). The primary endpoint was complete ARB decolonization at 1 month after FMT. Secondary endpoints included safety assessment and partial ARB decolonization. Microbiome sequencing was performed to investigate the influence of microbial composition of the transplanted material on the outcome of FMT. Results Twenty-five FMTs were performed in 20 participants (including 40% who had neutropenia) who were colonized by a median of 2 (range, 1-4) strains of ARB. The primary endpoint was reached in 15/25 (60%) of the FMTs and more frequently in cases in which there was no periprocedural use of antibiotics (79% vs 36%, P < .05). Among participants, 15/20 (75%) experienced complete ARB decolonization. There were no severe adverse events, and partial ARB decolonization was observed in 20/25 (80%) of the FMTs. The microbiota composition analysis revealed higher abundance of Barnesiella spp., Bacteroides, and Butyricimonas and greater bacterial richness in the fecal material, resulting in eradication of Klebsiella pneumoniae compared with nonresponders. Conclusions FMT in patients with blood disorders is safe and promotes eradication of ARB from the gastrointestinal tract. Clinical Trials Registration NCT02461199.

Simultaneous human herpesvirus 6-associated encephalitis and Guillain-Barré syndrome in a patient after matched unrelated donor haematopoietic stem cell transplantation.

Viral infections are still a serious diagnostic and therapeutic problem in patients undergoing alternative donor transplants. β-Herpesviruses (especially human herpesvirus type 5, 6 and 7) are recognized pathogens in this group of patients and may cause central nervous system disease. Guillain-Barré syndrome (GBS) is a very rare complication among stem cell transplant recipients and usually has been attributed to infection. We report a case of resolving simultaneous GBS and HHV-6-associated encephalitis in a haematopoietic stem cell transplant recipient with preceding reactivation of cytomegalovirus (CMV) infection. According to our knowledge this well-documented case is probably the first report from Poland.

Human Herpesvirus 7 in Allogeneic Hemopoietic Stem Cell Transplant Recipients in the Central Clinical Hospital in Warsaw: A Three-Year Survey

Objectives: Human herpesvirus 7 (HHV-7) is spread worldwide and has been described as a potential pathogen in immunosuppressed patients. Different clinical manifestations have been described including fever and skin rash; HHV-7 may also be a possible cofactor for cytomegalovirus disease in transplant recipients. Materials and Methods: A retrospective review of a group of 58 adult recipients of allogeneic hemopoietic stem cell transplantation was made. Serum samples taken in the range of 0–180 days after transplant were examined for presence of specific HHV-7 sequences using the quantitative real-time PCR method. Results: HHV-7 DNA was detected in plasma samples in 26 (45%) of the 58 recipients between day 20 and day 65 of transplantation. All of them developed fever of unknown origin; also HHV-5 DNA was detected in plasma samples collected from 11 HHV-7-positive patients. None of the described individuals died during detectable HHV-7 or HHV-5 viremia periods. Conclusions: There is a high frequency of detectable HHV-7 viral load in allogeneic stem cell transplant recipients in Poland. Limited availability and sensitivity of serological methods along with the necessity of rapid introduction of antiviral treatment has forced the development of molecular diagnostics. Furthermore, establishment of appropriate procedures for monitoring active HHV-7 infection is important to clarify the virus infection in transplant recipients.

Infections due to alphaherpesviruses in early post-transplant period after allogeneic haematopoietic stem cell transplantation: Results of a 5-year survey

BACKGROUND Infections caused by human α-herpesviruses usually have a benign course with recurrencies. However, they may become dangerous in immunocompromised hosts. In this case, molecular methods constitute a reliable diagnostic tool enabling rapid assessment of the efficacy of antiviral treatment strategies. OBJECTIVES We estimated the frequency of alphaherpesviral DNAemia and the viral load during early post-transplantation period after alloHSCT; we also analyzed association of the DNAemia and chosen parameters of the patients. STUDY DESIGN A cohort of 190 alloHSCT recipients from two hospitals in Warsaw, Poland, was examined weekly during 100-day early post-transplantation period using quantitative real time PCR assays. A total of 2475 sera samples were evaluated for the presence of α-herpesviral DNA in patients, of whom 117 (62%) received unrelated grafts, while the remaining 73 (38%) received grafts from sibling donors. All patients received standard antiviral prophylaxis with acyclovir. In the examined group, anti-HSV-1, anti-HSV-2 and anti-VZV IgGs were examined prior to transplantation, RESULTS: Within the study period, DNA of α-herpesviruses was detected in 44 patients (23.2%). Most patients tested positive for HSV-1 DNA (43 patients, 22.6%), single patient for HSV-2, and no patient positive for VZV. Clinical symptoms such as pneumonia, skin changes, elevated levels of aminotransferases were observed in five patients, four of these patients presented symptoms of GvHD at the same time. (2,6%). Statistics shows that GvHD (P<0.001) and matched unrelated donor as a source of HSCT (P=0.048) are associated with the development of HSV-1 DNAemia. CONCLUSIONS Although our data demonstrate frequent reactivation of HSV-1 in the early post-transplant period, the rate of symptomatic infections was low. We did not find association between HSV-1 viremia and mortality, but significant association with GvHD and donor source was observed.

Analysis of the shedding of three β-herpesviruses DNA in Polish patients subjected to allogeneic hematopoietic stem cell transplantation: Six-year follow up.

BACKGROUND Infections with human β-herpesviruses are common worldwide and are still frequent in patients after hematopoietic stem cell transplantation. Some data suggest that HHV-6 and HHV-7 could take part in CMV reactivation from latency and/or progression of CMV disease in immunosupressed patients. OBJECTIVES The aims of this study were: (1) to summarise retrospectively the results of β-herpesviruses DNA detection in a large group of adult allogeneic haematopoietic stem cell transplant recipients; and (2) to find a potential correlation between viruses belonging to this subfamily. STUDY DESIGN AlloHSCT recipients (N=142) were examined in the early post-transplant period (median=89 days). The presence of CMV, HHV-6 and HHV-7 was confirmed through detection and quantification of viral DNA, isolated from 1679 sera samples. RESULTS CMV DNA alone was detected in 23.9% of patients, while single HHV-6 and HHV-7 were detected in 14.8% and 9.9% of individuals, respectively. The reactivation of more than one virus was identified in 31% of analysed patients. In cases of concurrent infection, HHV-7 was detected at the same time as HHV-6, and both of them were usually reactivated before CMV. The kinetics of virus reactivation and measured viral load may suggest a potential role of HHV-6 and HHV-7 as co-factors in CMV reactivation. CONCLUSIONS The observed kinetics of virus reactivation may strongly suggest a potential role of HHV-6 and/or HHV-7 as co-factors of CMV reactivation. The co-infection with these β-herpesviruses could predispose patients after hematopoietic stem cell transplantation to a longer and more severe CMV infection.

The generation of CD8+ T-cell population specific for vaccinia virus epitope involved in the antiviral protection against ectromelia virus challenge.

Eradication of smallpox has led to cessation of vaccination programs. This has rendered the human population increasingly susceptible not only to variola virus infection but also to infections with other representatives of Poxviridae family that cause zoonotic variola-like diseases. Thus, new approaches for designing improved vaccine against smallpox are required. Discovering that orthopoxviruses, e.g. variola virus, vaccinia virus, ectromelia virus, share common immunodominant antigen, may result in the development of such a vaccine. In our study, the generation of antigen-specific CD8(+) T cells in mice during the acute and memory phase of the immune response was induced using the vaccinia virus immunodominant TSYKFESV epitope and CpG oligodeoxynucleotides as adjuvants. The role of the generated TSYKFESV-specific CD8(+) T cells was evaluated in mice during ectromelia virus infection using systemic and mucosal model. Moreover, the involvement of dendritic cells subsets in the adaptive immune response stimulation was assessed. Our results indicate that the TSYKFESV epitope/TLR9 agonist approach, delivered systemically or mucosally, generated strong CD8(+) T-cell response when measured 10 days after immunization. Furthermore, the TSYKFESV-specific cell population remained functionally active 2 months post-immunization, and gave cross-protection in virally challenged mice, even though the numbers of detectable antigen-specific T cells decreased.

Rapid Detection of NDM, VIM, KPC and IMP Carbapenemases by Real-Time PCR

Carbapenems are the most potent beta-lactams, characterized by broad spectrum of activity against Gramnegative and Gram-positive bacteria. Unfortunately, the dynamic dispersal of carbapenem resistance among nonfermentative bacteria and Enterobacteriaceae is an over-increasing problem and might lead to dangerous limitation of treatment options. Among three different mechanisms of resistance the enzyme production is of special importance. In this case, only one small gene is enough to express carbapenem resistance. The carbapenemase genes are often a part of integrons, which carry diverse arrays of resistance gene cassettes and just one transfer event is enough to disseminate multidrug resistance. Moreover, carbapenemase genes are often located within Mobile Genetic Elements. For these reasons carbapenemases are the most epidemiologically importance. Early detection and identification of carbapenemase producers among clinical isolates can avoid nosocomial infections. We have developed a multiplex Real-Time PCR assay based on the TaqMan technology for rapid detection and identifications of the most common carbapenemases in Europe NDM, VIM, KPC and IMP. There were tested 31 isolates Enterobacteriaceae (n=15) and non-fermentative Gram-negative bacillary (n=16), which acquire NDM, VIM, KPC, IMP, GIM or OXAs carbapenemases. The whole elaborated experiment, including DNA isolation and PCR cycling, lasts up to 2 h.