"Relative bradycardia" may also be present, which is low to normal heart rate despite the presence of a fever.Laboratory tests may show that kidney functions, liver functions, and electrolyte levels are abnormal, which may include low sodium in the blood. Chest X-rays often show pneumonia with consolidation in the bottom portion of both lungs. Distinguishing Legionnaires disease from other types of pneumonia by symptoms or radiologic findings alone is difficult; other tests are required for definitive diagnosis.People with Pontiac fever, a much milder illness caused by the same bacterium, experience fever and muscle aches without pneumonia. They generally recover in 2–5 days without treatment. For Pontiac fever, the time between exposure and symptoms is generally a few hours to two days. Cause
Over 90% of cases of Legionnaires disease are caused by Legionella pneumophila. Other types include L. longbeachae, L. feeleii, L. micdadei, and L. anisa. Transmission
Legionnaires disease is usually spread by the breathing in of aerosolized water or soil contaminated with the Legionella bacteria. Experts have stated that Legionnaires disease is not transmitted from person to person. In 2014, one case of possible spread from someone sick to the caregiver occurred. Rarely, it has been transmitted by direct contact between contaminated water and surgical wounds. The bacteria grow best at warm temperatures and thrive at water temperatures between 25 and 45 °C (77 and 113 °F), with an optimum temperature of 35 °C (95 °F). Temperatures above 60 °C (140 °F) kill the bacteria.
Myopericarditis is a combination of both myocarditis and pericarditis appearing in a single individual, namely inflammation of both the pericardium and the heart muscle. It can involve the presence of fluid in the heart. Risk factors
The appearance of myopericarditis is associated with infections such as acute tonsillitis, pneumonia, and gastroenteritis.Smallpox vaccination has been a known risk factor for myocarditis and pericarditis since the 1950s. In 1983, an incidence of myocarditis of 1 per 10 000 was reported among Finnish military personnel. Among US military service members vaccinated between December 2002 and March 2003 with Dryvax smallpox vaccine 18 cases of probable myopericarditis were reported, which was an incidence of 7.8 per 100 000 over 30 days.A meta-review from 2022 shows that the overall risk for myopericarditis after receiving a COVID-19 vaccine is low. In addition, the incidence of myopericarditis is significantly higher with a smallpox vaccination in comparison with a COVID-19 vaccination. The ACAM2000 smallpox vaccine has been known to cause myopericarditis in some people. Etymology
When ventricular function is normal, the term myopericarditis is used. Cases with impaired function are labeled perimyocarditis, though the two terms are often used interchangeably. Both will be reflected on an ECG.In a different naming scheme, inflammation that is predominantly pericarditis with some myocardial involvement is called myopericarditis, while predominant myocarditis with some pericardial involvement is called perimyocarditis. == References ==