Cardiovascular and Lymphatic Diseases Week 10

Cardiovascular and Lymphatic Systems

• Heart is located within the pericardium, composed of three layers: endocardium (interior), myocardium (middle), and epicardium (outer).
• Closed circulatory system facilitates the flow of gases, nutrients, and lymphocytes to and from the heart.
• Blood consists of water, proteins, and cells, while lymph is derived from blood and contains proteins and lymphocytes traveling through lymph vessels to nodes.

Bacterial Infections

• Bacteremia & Septicemia: Presence of bacteria/toxins in the blood; septicemia involves toxin-producing and multiplying bacteria, leading to systemic infections.
• Sepsis occurs in 2% of hospital admissions; inflammation becomes harmful, commonly resulting from pneumonia.
• Causative agents include Streptococci and Staphylococci, often acquired nosocomially.
• Signs/Symptoms of Sepsis: Lymphangitis, shock, confusion, blood-clotting abnormalities, and organ shutdown.
• Diagnosis performed through blood cultures; treatment generally involves IV antibiotics like penicillin or vancomycin.

Acute & Subacute Bacterial Endocarditis

• Infection of the endocardium and/or heart valves, can manifest acutely or subacutely based on onset speed.
• High-risk groups include individuals with damaged or artificial heart valves; acute endocarditis commonly caused by Staphylococcus aureus.
• Symptoms include fatigue, fever, anemia, joint pain, and potential for skin rashes.
• Diagnosis methods include blood cultures and echocardiograms; treatment requires high-dose IV antibiotics for 4-6 weeks.

Plague

• Historically significant pandemics: Justinian plague, Black Death, Orientalis outbreak in the late 19th century.
• In the U.S., 1-40 cases reported annually, primarily affecting Native Americans and those in contact with infected animals.
• Causative agent Yersinia pestis, a Gram-negative rod; spreads through bites or inhalation of infected material.
• Bubonic plague: Lymphatic system infection leading to swollen lymph nodes (buboes), can progress to pneumonic form.
• Treatment options include tetracycline and streptomycin; vaccine available but not for immediate protection.

Lyme Disease

• First identified in 1977, with over 25,000 cases reported in the U.S. in 2014; caused by Borrelia burgdorferi, a Gram-negative spirochete.
• Primarily transmitted by ticks, requiring a minimum of 36 hours of attachment for effective transmission.
• Symptoms include characteristic bull's-eye rash and joint pain; can develop cardiac and neurological effects.

Anthrax

• Caused by Bacillus anthracis, a Gram-positive endospore-forming bacterium, predominantly affects herbivorous animals.
• Three primary forms: cutaneous, gastrointestinal, and respiratory, with specific transmission routes for each.
• Cutaneous anthrax is the most common, with distinctive ulceration and significant mortality without treatment.
• Gastrointestinal and inhalation forms are more severe, with high fatality rates even with treatment.

Rocky Mountain Spotted Fever

• Caused by Rickettsia rickettsii, primarily transmitted by the dog tick; most cases are reported in the Southeastern U.S.
• Symptoms typically arise one week post-bite, including headache, fever, nausea, and rash, with possible joint pain.
• Treatment generally involves doxycycline; mortality rates can vary significantly based on strain strength.

Viral Cardiovascular and Lymphatic Diseases

• Notable diseases include Infectious Mononucleosis (caused by Epstein-Barr Virus), Ebola Virus Hemorrhagic Fever, and West Nile Fever.
• Infectious mononucleosis typically spreads through saliva and results in fatigue, sore throat, and swollen lymph glands, notably impacting B cells, leading to potential complications such as Hodgkin’s and Burkitt’s lymphoma.

Summary

• Understanding the nuances of various diseases affecting the cardiovascular and lymphatic systems supports better diagnosis, treatment, and prevention strategies.
• Critical to address risk factors, transmission methods, and treatment approaches to manage these diseases effectively.

Dive into the intricate systems of the cardiovascular and lymphatic diseases in Week 10. Explore the structures of the heart, blood flow, and the composition of blood and lymph. Understand how these systems work together to maintain bodily functions.