Microbiology - Cardiovascular and Lymphatic System Diseases

Vocabulary flashcards detailing bacterial, viral, protozoan, and helminthic diseases of the cardiovascular and lymphatic systems, including causative agents, reservoirs, and clinical manifestations.

Cardiovascular System Blood pH

The blood contains a very narrow pH range of approximately $7.4$.

Lymphatic System

Consists of lymph (interstitial fluid filtering out of capillaries), lymph vessels, lymph nodes, and lymphoid organs such as the spleen.

Lymph nodes

Structures containing fixed macrophages (dendritic cells), B cells, and T cells that maintain surveillance against foreign antigens.

Sepsis (septicemia)

A systemic inflammatory response to circulating pathogens in the blood; common causes include infections of the lungs, abdomen, and urinary tract by gram-negative rod bacteria or S. aureus.

Severe Sepsis

Sepsis combined with organ dysfunction or failure, associated with a $20-35\%$ mortality rate.

Septic shock

Sepsis combined with uncontrollable decreased blood pressure, resulting in a $30-70\%$ mortality rate.

Lymphangitis

Red streaks caused by inflammation of the lymphatic pathways, often seen as a symptom of sepsis.

Tularemia

A disease caused by Francisella tularensis, a gram-negative rod; characterized by ulceration at the site of entry, sepsis, and pneumonia.

Brucellosis

Infection caused by Brucella spp. leading to malaise, sepsis, chronic joint pain, and fever spikes as high as $104^\circ C$.

Bacillus anthracis

A gram-negative, endospore-former that causes anthrax; endospores can survive in soil for up to $60$ years.

Ischemia

The loss of blood supply to a tissue.

Gangrene

Soft tissue death due to ischemia, typically associated with infection.

Gas gangrene

An infection caused by Clostridium perfringens where the bacteria ferment carbohydrates and produce $CO_2 + H_2$ gases.

Pasteurella multocida

A bacterium introduced by the bite of a dog or cat that can cause septicemia.

Cat-scratch disease

Disease caused by Bartonella henselae, which presents as a purple papule at the infection site followed by headaches, malaise, and fever.

Relapsing fever

A disease caused by Borrelia spp. characterized by fever, jaundice, and rose-colored spots that reappear due to emerging antigenic variants.

Lyme Disease

Infection caused by B. burgdorferi via tick bites, beginning with a bull’s eye rash and potentially progressing to joint pain, heart, and neurological disease.

Epidemic typhus

Disease caused by Rickettsia typhi, prevalent in crowded conditions and spread by human house lice.

Rocky Mountain Spotted Fever

Also known as tickborne typhus fever, caused by Rickettsia rickettsii and transmitted by Dermacentor species ticks.

Endocarditis

Inflammation of the inner layer of the heart (endocardium), typically due to microbial growth.

Subacute bacterial endocarditis

Slow-developing infection typically caused by alpha-hemolytic streptococci, staphylococci, or enterococci, often arising from a focus like tooth extraction.

Acute bacterial endocarditis

Rapid destruction of heart valves, usually caused by Staphylococcus aureus.

Rheumatic fever

An autoimmune complication of Streptococcus pyogenes infections, often following an untreated sore throat and causing inflammation of heart valves.

Infectious mononucleosis

Caused by the Epstein-barr virus (human herpes virus-4), it causes proliferation of atypical lymphocytes and is transmitted via saliva.

Cytomegalovirus (HHV-5)

A teratogenic virus causing intranuclear inclusion bodies and host cell cytomegaly; it can cause congenital infection and neurological damage in a fetus.

Viral hemorrhagic fevers (VHFs)

Illnesses caused by viral infections that result in both fever and uncontrolled bleeding (hemorrhaging).

Dengue Fever

Disease caused by an arbovirus transmitted by Aedes aegypti; characterized by fever, muscle/joint pain, and rash.

Yellow Fever

Arboviral disease resulting in fever, chills, and jaundice; the first animal virus identified (1901 by Walter Reed).

BSL-4 VHFs

Refers to Marburg, Ebola, and Lassa fever viruses, among the most lethal human pathogens; Ebola is associated with $30-90\%$ mortality.

Hantavirus pulmonary syndrome (HPS)

A fatal pulmonary infection contracted by inhalation of dried rodent urine, causing the lungs to fill with fluid.

Toxoplasma gondii

An obligate intracellular parasite that only sexually reproduces in felines; causes toxoplasmosis in humans.

Malaria Pathogenesis

Sporozoites reproduce in the liver and release merozoites to infect red blood cells; transmitted by Anopheles mosquitoes.

Schistosomiasis

Chronic illness caused by the blood fluke Schistosoma; larvae hatch from eggs in water to infect snails before penetrating human skin.

Cercariae

Free-swimming larvae of Schistosoma released from the intermediate host (snail) that penetrate human skin.