A Rare Case of Leuconostoc pseudomesenteroides Bacteremia and Refractory Septic Shock.

Leuconostoc species are rare causes of bacteremia and are commonly mistaken for Streptococcus species. Due to their inherent resistance to commonly used drugs, they are often overlooked resulting in poor and sometimes lethal outcomes. While there are not many reported cases of this bacterial infection, Leuconostoc species are important to consider when faced with a highly drug-resistant bacterial strain. We present here a case of a 29-year-old male who presented with an out-of-hospital cardiac arrest, initially resuscitated but ultimately succumbing to his illness. This is a unique case in which our patient was subsequently found to have a rare bloodstream infection with Leuconostoc pseudomesenteroides.

A Case Series of Secondary Spontaneous Pneumomediastinum and Pneumothorax in Severe COVID-19 Pneumonia.

Introduction Pneumomediastinum and pneumothorax are uncommon complications in COVID-19 patients. The exact prevalence, etiology, and outcomes are not well known. We report a case series of patients in our institution with COVID-19 related pneumomediastinum and pneumothorax and address these questions. Methods We conducted a single-center retrospective chart review of patients admitted at our institution with a positive polymerase chain reaction (PCR) confirming the diagnosis of COVID-19. A cohort of 500 potential study candidates was identified, of whom eight were investigated. Demographic data, hospital course, patient co-morbidities, and outcome data were collected. Results Eight patients were included in our study who were identified as having an event (i.e., pneumomediastinum and/or pneumothorax) during the specified timeframe. Overall, 62% of patients were on high-flow nasal cannula with an average FiO2 of >70%. The average oxygen saturation//fraction of inspired oxygen (SpO2/FiO2) ratio leading up to an event was 113.7286 (range: 101.11-130.66), and all of the patients not on mechanical ventilation met the criteria for acute respiratory distress syndrome (ARDS) based on the Kigali definition with SpO2/FiO2 < 315. The three patients who developed an event while requiring mechanical ventilation both had PaO2/FiO2 < 100, consistent with severe ARDS at the time of an event. The mean time in days, counted from the day of hospital admission until an event, was 10 days (range: 3-23 days). None of the cases had documented pulmonary parenchymal disease prior to developing COVID-19. To the best of our knowledge, these events were not iatrogenic in nature. Conclusion Secondary spontaneous pneumomediastinum and pneumothorax are rare albeit well-documented phenomena in hospitalized patients with COVID-19 infection. Interestingly, the majority of patients in our study were on high-flow nasal cannula at the time of an event. The majority of previously published data on this topic are on those who required positive pressure ventilation; however, there have been more recent papers that also describe these events in non-mechanically ventilated patients. The exact pathophysiology remains unknown, but it is likely multifactorial, and additional studies are needed to further evaluate this phenomenon.