May 8 2020
Q: I watched the video by Dr. Hansen titled “What Doctors Are Learning From Autopsy Findings of Coronavirus (COVID-19) patients”. Thoughts?
Dr. Why: “Dr. Hansen, I suggest that you to go back to school and review pathogenesis of viral infections and viral pneumonia in particular. Please stop fear mongering by declaring we know little and all of these symptoms/findings are unique. Please…”
Here is the list of complications of influenza as per Uptodate.com:
Pneumonia - the major complication of influenza is pneumonia, which occurs most frequently in certain groups of patients with underlying chronic illnesses who are classified as high risk
Primary influenza pneumonia — Primary influenza pneumonia occurs when influenza virus infection directly involves the lung, typically producing a severe pneumonia;
The primary mechanism of influenza pathophysiology is a result of lung inflammation and compromise caused by direct viral infection of the respiratory epithelium, combined with the effects of lung inflammation caused by immune responses recruited to handle the spreading virus. This inflammation can spread systemically and manifest as a multiorgan failure, but these consequences are generally downstream of lung compromise and severe respiratory distress. Some associations have also been observed between influenza virus infection and cardiac sequelae, including increased risk of myocardial disease in the weeks following influenza virus infection. The mechanisms of this, beyond a general inflammatory profile, are still unresolved.
Secondary bacterial pneumonia is an important complication of influenza and contributes substantially to morbidity and mortality, especially among individuals ≥65 years of age. The hallmark of the clinical presentation in patients with secondary bacterial pneumonia is the exacerbation of fever and respiratory symptoms after initial improvement in the symptoms of acute influenza;
Mixed viral and bacterial pneumonia — It is common for patients with influenza and a complicating pneumonia to have features of both viral and bacterial pneumonia. In these cases, patients may have either a gradual progression of illness or a transient improvement followed by worsening.
Myositis and rhabdomyolysis — Other important complications of influenza include myositis and rhabdomyolysis, which have been reported most frequently in children;
Cardiac complications — Several cardiac complications have been described in patients with influenza infection:
Electrocardiographic (ECG) changes – ECG changes are frequently noted in patients who develop influenza but are most often attributed to the underlying cardiac disease rather than to direct involvement of the heart with influenza virus;
Acute myocardial infarction – Several studies have shown an association between influenza infection and acute myocardial infarction (MI);
Myocarditis and pericarditis – Myocarditis and pericarditis have generally been considered rare complications of influenza. However, in a study of fatal cases of influenza B infection, myocarditis was found commonly at autopsy; myocardial injury was identified in 20 of 29 patients (69 percent) who had cardiac specimens available for histology, and 10 of these had unequivocal myocarditis;
Central nervous system involvement - CNS disease may be associated with influenza, including encephalopathy, encephalitis, transverse myelitis, aseptic meningitis, and Guillain-Barré syndrome. However, the pathogenesis of the CNS illnesses associated with influenza remains poorly understood;
Influenza presenting as sepsis - the immune response to influenza shares many common pathways with the response to bacteria, thus it should not be surprising that an influenza virus infection can have a very similar clinical presentation to bacterial sepsis. Specifically, several studies have demonstrated that both Toll-like receptors 2 and 4, which are the main receptors for Gram-positive and Gram-negative bacteria, are also related to influenza pathogenicity. In addition, similar to bacterial sepsis, endothelial damage and microvascular permeability changes leading to tissue edema and organ failure have been observed with influenza virus infections;
Toxic shock syndrome associated with S. aureus infection and acute influenza has been described. Most reported cases have been due to influenza B.
Got the point?