Chapter 25: Circulatory and Lymphatic System Infections

Myocardium

Middle tissue of the heart

Endocardium

Inner tissue of the heart

Pericardium

Outer tissue of the heart

Bacteremia

Bacteria in the blood

Septicemia

Bacteria in blood through injection

Viremia

Virus in blood

Toxemia

Toxins in blood

Endocarditis

Endocardium inflammation

Pericarditis

Pericardium inflammation

Vasculitis

Blood vessel inflammation

Toxic Shock Syndrome

Pathogen: Staphylococcus aureus

Signs/Symptoms: Sudden high fever, vomiting, diarrhea, hypotension, death.

Transmission: Pathogens from localized infection spread to bloodstream; pathogens introduced on tampons or other intravaginal products.

Toxic Shock-Like Syndrome

Pathogen: Streptococcus pyogenes

Signs/Symptoms: Sudden high fever, vomiting, diarrhea, acute respiratory distress syndrome (ARDS), hypoxemia, necrotizing fasciitis, death.

Transmission: Sequela of streptococcal skin or soft-tissue infection

Endocarditis/pericarditis

Pathogen: SStaphylococcus spp., Streptococcus spp., Enterococcus spp., HACEK bacilli

Signs/Symptoms: Chest pain difficulty breathing, dry cough, fever'; potentially fatal damage to heart valves

Transmission: Pathogens introduced to bloodstream via contaminated catheters, dental procedures, piercings, or wounds.

Osteomyelitis

Pathogen: Staphylococcus aureus, Streptococcus pyogenes, others.

Signs/Symptoms: Inflammation of bone tissue, leading to fever, localized pain, edema, ulcers, bone loss

• After organism go into the blood, they can go into bone tissue

Transmission: Pathogens introduced through trauma, prosthetic joint replacement, or from other infected body site via bloodstream.

Puerperal Sepsis

Postpartum infection “Child bud fever”

Pathogen: Streptococcus pyogenes, many others

Signs/Symptoms: Rapid onset fever, shock, and death

Transmission: Pathogens introduced during or immediately following childbirth.

Puerperal

During or immediately after child birth.

Gas Gangrene

Pathogen: Clostridium perfringens, other Clostridium spp. ANAEROBIC

Signs/Symptoms: Rapidly spreading myonecrosis, edema, yellowish and then purple discharge from wound, pockets of gas in tissues, septic shock and death.

• Predisposing factors: surgical incisions, compound fractures, diabetic ulcers, septic abortions, punction wound, gunshot wound, stab wound

Transmission: Germination of endospores in ischemic tissues, typically due to injury or chronic disease (e.g., diabetes)

• Virulence Factors - Toxins and endoenzymes

• Requires damage, dead tissue, and anaerobic conditions

• Hyperbaric oxygen therapy

• Immediate scanning of wound

Brucellosis

Pathogen: Brucella melitensis, B. abortus, B. canis, B. suis

Signs/Symptoms: Granuloma, undulating fever, chronic flu-like symptoms.

Transmissions: Direct contact with infected livestock or animals

Undulant fever

fluctuating fevers, sweats, and muscle pain. The disease is often transmitted from infected animals (cattle, sheep, goats, etc.)

Plague

Pathogen: Yersinia pestis (zoonotic)

Signs/Symptoms: Bubonic; buboes, fever, internal hemorrhaging; septicemic: fever, abdominal pain, shock, DIC, necrosis in extremities; pneumonic: acute pneumonia, respiratory failure, shock. All forms have high mortality rates.

Transmission: Flea vectors or consumption of infected animal; transmission of pneumonic plague between humans via respiratory aerosols

• Bubonic → Septicemic → pneumonic (most dangerous

DIC

Disseminated Intravascular Coagulation

• Abnormal blood clotting throughout the bodys blood vessels, causes internal bleeding and organ failure

Epidemic typhus

Pathogen: Rickettsia

Sign/Symptoms: High fever, body aches, rash; potentially fatal damage to heart and brain.

Transmission: From rodent reservoir via the body louse vector

• Vector dependent

Murine (endemic) typhus

Pathogen: Rickettsia typhi

Signs/Symptoms: Low-grade fever, rash, headache, cough

Transmission: From rodents or between humans via rat flea vector

• Vector dependent

Rocky Mountain Spotted Fever

Pathogen: Rickettsia rickettsii

• Common in North America

Signs/Symptoms: High fever, headache, body aches, nausea and vomiting, petechial rash; potentially fatal hypotension and ischemia due to blood coagulation

Transmission: From rodent reservoir via tick vectors

• Vector dependent

Rickettsia

Tiny, obligate intracellular parasites

• No human to human transmission

• Vector dependent

Lyme Disease

Pathogen: Borrelia burgdoferi

Signs/Symptoms: Early localized: Bull’s eye rash, malaise, headache, fever, muscle stiffness; early disseminated: stiff neck, facial paralysis, arthritis, carditis; late stage; arthritis, meningitis, possibly fatal.

BULLS-EYE MARK

• Nonfatal; slow progressive syndrome

• Mimics neuromuscular and meumatoid condition

Transmission: From deer, rodent, bird reservoirs via tick vector

• Thin spirochetes

Infectious Mononucleosis (IM)

“Mono”/ “Kissing disease”

Pathogen: Epstein-Barr virus (HHV-4), cytomegalovirus (HHV-5)

Signs/Symptoms: Pharyngitis, fever, extreme fatigue; swelling of lymph nodes, spleen, and liver

• Infects lymphoid tissue and salivary glands

• Self-limiting (after 1-2 months)

  • Rarely reactivated may be asymptomatic

Transmission: Contact with body fluids (e.g., saliva, blood, semen)

Burkitt Lymphoma

Pathogen: Epstein-Barr virus (HHV-4)

Signs/Symptoms: Rapid formation of malignant B-cell tumors, oral hairy leukoplakia; fatal if not promptly treated

Transmission: Contact with body fluids (e.g., saliva, blood, semen): primarily affects patients immunocompromised by HIV malaria

• Endemic form (common in Africa) frequently involves jaw and facial bones → facial swelling

Cytomegalovirus infections

Pathogen: Cytomegalovirus (HHV-5)

Signs/Symptoms: Usually asymptomatic but may cause development issues in developing fetus; in transplant recipients, may cause fever, transplant, death

Transmission: Contact with body fluids, blood transfusions, organ transplants; infected mothers can transmit virus to fetus transplacentally or to newborn in breastmilk, saliva.

• High infection rates (in humans)

• Fetuses, newbornes, immunodeficient adults - highly susceptible.

• TORCH

• Latent in various tissues

Yellow Fever

Pathogen: Yellow-fever virus

Signs/Symptoms: Dizziness, fever, chills, headache, myalgia, nausea, vomiting, constipation, fatigue; moderate to severe cases may include jaundice, rash, mucosal, hemorrhaging, seizures, shock, and death

Transmission: From monkeys to humans or between humans via Aedes or Haemagogus mosquito vectors

Dengue Fever (Breakbone fever)

Pathogen: Dengue fever viruses 1-4

Signs/Symptoms: Fever, headache, extreme bone and joint pain, abdominal pain, vomiting, hemorrhaging; can be fatal.

Transmission: Transmitted between humans by A. aegypi and A. albopictus vectors

Chikungunya fever

Pathogen: Chikungunya virus

Signs/Symptoms: Fever, rash, joint pain, mild fever

Transmission: Transmitted between humans by Aedes aegypti and A. albopictus vectors

Ebola Virus Disease

Pathogen: Ebola Virus

Signs/Symptom: Fever, headache, joint pain, diarrhea, vomiting, hemorrhaging in the gastrointestinal tract, organ failure; often fatal

• Disrupts blood clotting process → internal and external bleeding

• Directly invades and damages endothelial cells.

Transmission: Contact with body fluids (e.g., blood, saliva, sweat, urine, feces, vomit); highly contagious

Human Immunodeficiency Virus

Pathogen: Human immunodeficiency virus (HIV)

Sign/Symptoms: Flu-like symptoms during acute stage, followed by long period of clinical latency; final stage (AIDS) includes fever, weight loss, wasting syndrome, dementia, and opportunistic secondary infections leading to death.

• Interferes with body’s ability to fight infections

• Only infects Helper T-Cells (CD4)

• No cure (due to latency)

  • ART: Suppress and prevent the spread.

Transmission: Contact with body fluids (e.g., sexual contact, use of contaminated needles)

200

AIDS: <____cell/CD4

Malaria

Pathogen: Plasmodium vivax, P. malariae, P. falciparum, P. ovale.

Signs/Symptoms: Extreme fever, chills, myalgia, nausea, and vomiting, possibly leading to organ failure and death

Transmission: Between humans via Anopheles mosquito vector

• 300-500 million new cases and ~2million deaths per year,

• Tropical and Subtropical

Malaria Lifecycle

Asexual Phase → Human host

Sexual Phase → Mosquito host

• Cycles of extreme fever, chills, and sweating are classic signs and symptoms

Toxoplasmosis

Pathogen: Toxoplasma gondii

• Apicomplexan parasite

• Complex life cycle that involves multiple hosts

• Unsporulated oocytes, non-infective stage of protozoa

Sign/Symptoms: Tissue cysts; in pregnant women, birth defects or miscarriage

• TORCH

Transmission: Contact with feces of infected cat; eating contaminated vegetables or undercooked meat of infected animal

• In cat poop

• Mother to fetus

• Blood transfusions or organ transplantation

Chagas Disease

“Dookie kiss”

Pathogen: Trypanosoma cruzi

Sign/Symptoms: Fever, headache, body aches, swollen lymph nodes; potentially fatal

Transmission: Between humans or animal reservoirs via triatomine (kissing bug) vector