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Background: Despite multiple reports of increased incidence of bacterial respiratory tract infections following COVID-19 globally, the microbiology is not fully elucidated. In this study, we describe the incidence and microbiology of bacterial infections and the burden of multidrug resistant organisms (MDROs) in hospitalized COVID-19 patients with community-acquired pneumonia (CAP), non-ventilated hospital acquired pneumonia (NVHAP) or ventilator-associated pneumonia (VAP). To our knowledge, this is the first study that compares the microbiology of VAP and NVHAP in COVID-19 patients.Methods:This is a longitudinal retrospective cohort study conducted at the American University of Beirut Medical Center (AUBMC), a tertiary-care center in Lebanon. Adult patients with confirmed COVID-19 who were hospitalized between March 2020 and September 2021 were included. Only pathogens isolated within 42 days of positive SARS-CoV-2 tests were included. Bacterial isolates identified in hospital-acquired pneumonia (HAP) were divided into 3 groups based on the time of acquiring pneumonia after admission: hospital day 3-14, 15-28 and 29-42.Results:Out of 1674 patients admitted with COVID-19, 159 (9.5%) developed one or more respiratory infections. Overall, Gram-negative bacteria were predominant (83.5%) andS. maltophiliawas the most common pathogen (14.3%).S. aureusandHaemophilusspp. were implicated in most CAPs, whileK. pneumonia,S. maltophilia and E. coliwere the top culprits in HAP during hospital days 3-14, 15-28 and 29-42 respectively. Among 231 isolates obtained, 59 (25.5%) were MDROs, seen in higher proportion in HAP, especially among patients with prolonged hospital stay (> 4 weeks). Non-fermenter Gram-negative bacilli (NFGNB) (OR = 3.521, p-value = 0.000), particularlyS. maltophilia(OR = 3.236, p-value = 0.022), were significantly more implicated in VAP compared to NVHAP.Conclusions:COVID-19 patients hospitalized at AUBMC are at a slightly lower risk for bacterial respiratory infections compared to other studies. The pathogens varied according to the time since hospitalization. The burden of NFGNB and S.maltophiliais particularly high in COVID-19 VAP, indicating the need for further studies targeting these pathogens. A high rate of bacterial resistance was found which has important implications in guiding therapeutic decisions in COVID-19 patients who acquire bacterial infections.

A paraganglioma is a rare extra-adrenal neuroendocrine tumour with a variable clinical presentation. A paraganglioma can arise anywhere along the sympathetic and parasympathetic chains, but it can occasionally emerge from unusual locations such as the liver and the thoracic cavity. We report a rare case of a woman in her 30s who presented to our emergency department with symptoms of chest discomfort, episodic hypertension, tachycardia and diaphoresis. A diagnostic approach including a chest X-ray, an MRI and a positron emission tomography–CT scan showed a large exophytic liver mass protruding into the thoracic cavity. For further characterisation of the mass, a biopsy of the lesion was performed, demonstrating that the tumour is of neuroendocrine origin. This was supported by a urine metanephrine test showing high levels of catecholamine breakdown products. Treatment consisted of a unique multidisciplinary approach involving hepatobiliary and cardiothoracic surgery allowing a safe and complete extermination of the hepatic tumour and its cardiac extension.

Cardiovascular disease (CVD) continues to be the primary cause of global mortality. Vascular smooth muscle cells (VSMCs) are integral components of vascular structure and function, evident by their vital roles in modulating blood flow and pressure. Such roles exist due to the differentiated contractile phenotype of VSMCs. However, VSMCs may switch to a dedifferentiated, proliferative synthetic phenotype in a phenomenon known as phenotypic switching. This switch involves dramatic changes in VSMC migration, proliferation, gene expression programs, differentiation, cellular stiffness and extracellular matrix (ECM) deposition. In this review, we explore the role of the small GTPase Rho and its effector, Rho-associated kinase (ROCK), in phenotypic switching as well as apoptotic pathways in VSMCs. We critically dissect how RhoA promotes cell migration and proliferation as well as its role in modulating the expression of a battery of VSMC marker proteins. We also discuss how RhoA modulates apoptosis, induces dedifferentiation, increases vascular stiffness, or modifies ECM accumulation. These alterations in VSMC phenotypes contribute to multiple vascular dysfunctions, including hypertension and atherosclerosis. Understanding the molecular underpinnings and the signaling pathways involved in these altered phenotypes may provide novel avenues of drug design and other therapeutic interventions for the management of CVDs.

Paraneoplastic syndromes are rare abnormal endocrine or immune responses triggered by neoplasms. Chronic inflammatory demyelinating polyneuropathy (CIDP) is one such example. CIDP is an acquired, immune-mediated neuropathy affecting the peripheral nerves and nerve roots. It is associated with many types of cancers, especially haematological malignancies. We report the case of a man in his 60s who presented to the emergency department with acute symptoms of upper and lower extremity paresis and decreased sensation in the toes and tips of his fingers. Laboratory tests were normal. Electrodiagnostic studies showed diffuse motor and sensory dysfunction in all extremities; a diagnosis of CIDP was consequently made. Imaging studies showed a large left lobe liver mass. Subsequent biopsy revealed histopathological findings characteristic of hepatocellular carcinoma. After failure of medical treatment with intravenous immunoglobulin and corticosteroids, laparoscopic resection of the tumour was planned, performed and resulted in complete resolution of symptoms. At 18 months postoperatively, the patient was asymptomatic.