Lethal Waterhouse-Friderichsen syndrome caused by Capnocytophaga canimorsus in an asplenic patient.

BACKGROUND: Capnocytophaga canimorsus, a Gram-negative rod, belongs to the Flavobacteriaceae family and colonizes the oropharynx of dogs and cats. Infections with C. canimorsus are rare and can induce a systemic infection with a severe course of the disease. So far, only five case reports of C. canimorsus infections associated with Waterhouse-Friderichsen Syndrome (WFS) have been reported with only two of the patients having a history of splenectomy. CASE PRESENTATION: Here, we report a fatal case of WFS due to C. canimorsus bacteremia and mycetal superinfection in a 61-year-old female asplenic patient. Despite extensive therapy including mechanical ventilation, antibiotic coverage with meropenem, systemic corticosteroids medication, vasopressor therapy, continuous renal replacement therapy, therapeutic plasma exchange, multiple transfusions of blood products and implantation of a veno-arterial extracorporeal membrane oxygenation the patient died 10 days after a dog bite. The autopsy showed bilateral hemorrhagic necrosis of the adrenal cortex and septic embolism to heart, kidneys, and liver. Diagnosis of C. canimorsus was prolonged due to the fastidious growth of the bacteria. CONCLUSIONS: The occurrence of a severe sepsis after dog bite should always urge the attending physician to consider C. canimorsus as the disease-causing pathogen. A therapeutic regimen covering C. canimorsus such as aminopenicillins or carbapenems should be chosen. However, despite maximum therapy, the prognosis of C. canimorsus-induced septic shock remains very poor. Asplenic or otherwise immunocompromised patients are at higher risk for a severe course of disease and should avoid exposure to dogs and cats and consider antibiotic prophylaxis after animal bite.

Incidence and predictors of cardiac arrhythmias in patients with COVID-19 induced ARDS.

INTRODUCTION: Recent studies suggest cardiac involvement with an increased incidence of arrhythmias in the setting of coronavirus disease 2019 (COVID-19). The aim of this study was to evaluate the risk of potentially lethal arrhythmias and atrial fibrillation in patients with COVID-19-induced acute respiratory distress syndrome (ARDS) and to elicit possible predictors of arrhythmia occurrence. METHODS AND RESULTS: A total of 107 patients (82 male, mean age 60 ±â€¯12 years, median body mass index 28 kg/m2) treated for COVID-19-induced ARDS in a large tertiary university hospital intensive care unit between March 2020 and February 2021 were retrospectively analyzed. Eighty-four patients (79%) had at least moderate ARDS, 88 patients (83%) were mechanically ventilated, 35 patients (33%) received vvECMO. Forty-three patients (40%) died during their hospital stay. Twelve patients (11%) showed potentially lethal arrhythmias (six ventricular tachycardia, six significant bradycardia). Atrial fibrillation occurred in 27 patients (25%). In a multivariate logistic regression analysis, duration of hospitalization was associated with the occurrence of potentially lethal arrhythmias (p = 0.006). There was no association between possible predictive factors and the occurrence of atrial fibrillation. Invasive ventilation, antipsychotics, and the QTc interval were independently associated with acute in-hospital mortality, but this was not arrhythmia-driven as there was no association between the occurrence of arrhythmias and mortality. CONCLUSION: In this relatively young population with COVID-19-induced ARDS, the incidence of potentially lethal arrhythmias was low. While overall mortality was high in these severely affected patients, cardiac involvement and arrhythmia occurrence was not a significant driver of mortality.

Dysphagia in Patients With Severe Coronavirus Disease 2019-Potential Neurologic Etiologies.

IMPORTANCE: Dysphagia is a common complication of critical illness, and many known risk factors are also present in critically ill coronavirus disease 2019 victims. OBJECTIVES: To investigate dysphagia in patients with severe coronavirus disease 2019. DESIGN SETTING AND PARTICIPANTS: In this case series, we report results of dedicated evaluation of swallowing function in six consecutive, tracheotomized coronavirus disease 2019 patients after they had survived acute respiratory distress syndrome and were weaned from the respirator. MAIN OUTCOMES AND MEASURES: Dysphagia was assessed with flexible endoscopic evaluation of swallowing. RESULTS: Three patients suffered from severe dysphagia and airway compromise precluding decannulation, whereas in the other, three swallowing was less critically impaired, and the tracheal cannula could be removed. Four patients presented with additional laryngeal dysfunctions not typically seen in acute respiratory distress syndrome survivors. CONCLUSION AND RELEVANCE: Dysphagia with impaired airway protection is a key feature in coronavirus disease 2019 acute respiratory distress syndrome survivors. Apart from critical illness polyneuropathy, coronavirus disease 2019-related involvement of the peripheral and central nervous system may contribute to swallowing impairment and laryngeal dysfunction.

Mitogen-activated protein kinase 2 regulates physiological and pathological bone turnover.

The objective of this study was to investigate the role of the serine-threonine kinase mitogen-activated protein kinase 2 (MK2) in bone homeostasis. Primary bone cell cultures from MK2(+/+) and MK2(-/-) mice were assessed for osteoclast and osteoblast differentiation, bone resorption, and gene expression. Bone architecture of MK2(+/+) and MK2(-/-) mice was investigated by micro-computed tomography and histomorphometry. Ovariectomy was performed in MK2(+/+) and MK2(-/-) mice to assess the role of MK2 in postmenopausal bone loss. Osteoclastogenesis, bone resorption, and osteoclast gene expression were significantly impaired in monocytes from MK2(-/-) compared to MK2(+/+) mice. Mechanistically, loss of MK2 causes impaired DNA binding of c-fos and nuclear factor of activated T cells cytoplasmic 1 (NFATc1) to tartrate-resistant acid phosphatase (TRAP) and the calcitonin receptor gene promoter. In addition, MK2(-/-) mice showed an age-dependent increase in trabecular bone mass and cortical thickness, fewer osteoclasts, and lower markers of bone resorption than MK2(+/+) mice. Furthermore, MK2(-/-) mice were protected from ovariectomy-induced bone loss. Osteoblastogenesis and bone formation were unchanged in MK2(-/-) mice, whereas osteoblast expression of osteoprotegerin (OPG) and serum levels of OPG were higher in MK2(-/-) than in MK2(+/+) mice. Loss of MK2 effectively blocks bone resorption and prevents the development of postmenopausal bone loss. Small-molecule inhibitors of MK2 could thus emerge as highly effective tools to block bone resorption and to treat postmenopausal bone loss.