No abstract

The incidence of chorioamnionitis varies widely. The highest incidence is reported in preterm deliveries. Among preterm deliveries, chorioamnionitis usually occurs after preterm premature rupture of membranes (PPROM). To date, only five cases of chorioamnionitis due to Serratia marcescens were reported. Here we present a case of a pregnant woman with chorioamnionitis due to Serratia marcescens who delivered a premature neonate at 28 weeks and four days of gestation. We also conducted a review of the literature in order to identify and characterize the clinical presentation and outcomes of this rare infection. A 36 year old female (gravida 9, para 6) was admitted with cervical effacement of 16mm and intact membranes at gestational age of 25 weeks and five days. One week following her admission PPROM was noticed. Treatment with the standard antibiotic regimen for PPROM was initiated. Thirteen days after the diagnosis of PPROM (28 weeks and four days) she developed chills, abdominal pain, sub febrile fever, tachycardia, leukocytosis and fetal tachycardia, and a clinical diagnosis of chorioamnionitis was made. An urgent CS was performed. In the first post-operative day the patient developed surgical sight infection. Cultures obtained from the purulent discharge of the wound, as well as cultures from the placenta and uterine cavity that were obtained during surgery grew Serratia marcescens. The patient was treated with Meropenem for six days, with a good clinical response. We present a rare case of nosocomialy acquired Serratia marcescens chorioamnionitis in a patient with PPROM. This case emphasizes the need for good infection control measures. Our favorable outcome together with the scares reports in the literature, add insight into this type of rare infection.

Background Waning vaccine-immunity and an increased incidence of COVID-19 during the Omicron outbreak led the Israeli Ministry of Health to recommend a fourth dose of BNT162b2 for high-risk individuals. This study assessed the effect of that dose for hospitalized patients with severe/critical, breakthrough COVID-19. Methods In this multi-center retrospective cohort study of hospitalized adults with severe/critical COVID-19 in Israel, from 01/15/2022–01/31/2022, cases were divided according to the number of vaccinations received. Poor outcome was defined as mechanical ventilation or in-hospital death, and was compared between 3- and 4-dose vaccinees using logistic regression. Results Included were 1,049 patients, median age 80 years (IQR 69-87), 51% males. Among them, 394 were unvaccinated, 386 had received 3 doses and 88 4 doses. The 3-dose group was older, had more males and immunosuppression, but with similar outcomes, 49% vs. 51% compared to unvaccinated patients (p = 0.72). Patients after 4 doses were similarly older and immunosuppressed, but had better outcomes compared to unvaccinated patients, 34% vs. 51% (p < 0.01). We examined independent predictors for poor outcome in patients with either 3 or 4 doses, received a median of 161 (IQR 147-168) or 14 (IQR 10-18) days before diagnosis, respectively. Receipt of the fourth dose was associated with protection: OR 0.51 (95%CI 0.3-0.87), as was Remdesivir OR 0.65 (95%CI 0.44-0.96). Male sex, chronic renal failure and dementia were associated with poor outcomes. Conclusions Among hospitalized patients with severe/critical breakthrough COVID-19, a recent fourth dose was associated with significant protection against mechanical ventilation or death, compared to three doses.

Summary Peripheral blood mononuclear cells (PBMC) of untreated, HIV‐infected patients contain HIV‐specific CD8 T cells as well as their corresponding targets, HIV‐infected CD4 T cells. To determine if CD4 T‐cell depletion in HIV‐infected patients may result from autologous CD8–CD4 T‐cell interaction, CD8 and CD4 T cells procured from PBMC of acute and chronic untreated HIV‐infected patients were sorted and co‐incubated. Formation of CD8‐CD4 T‐cell conjugates was observed by fluorescence microscopy. Apoptosis of CD4 T cells in conjugation was recorded by digitized images and was further observed and measured by FACS using Annexin staining. Perforin expression in the CD8 T cells was measured using intracellular monoclonal perforin antibody staining. HIV DNA in the conjugated CD4 T cells was detected by in situ PCR. We found that 6·1 ± 0·5% of CD4 T cells from acute HIV‐infected patients and 3·0 ± 0·5% from chronic HIV‐infected patients formed CD8–CD4 T‐cell conjugates. Annexin binding and cell morphology typical of apoptosis were observed in the conjugated CD4 T cells. The majority of CD8 T cells that had conjugated to CD4 T cells expressed perforin. The conjugated CD4 T cells exhibited nuclear HIV DNA. CD8 T cells and HIV‐infected CD4 T cells, both procured from the PBMC of untreated HIV‐infected patients, form conjugates. Apoptotic lytic activity has been observed in the conjugated CD4 T cells. We propose that CD4 T‐cell annihilation in HIV‐infected patients results, at least in part, from the interactions of perforin‐rich CD8 T cells with autologous, HIV‐infected CD4 T cells.