Exam 4 (Micro) pt.1

Staphylococcus aureus

A prominent pathogenic species among staphylococci responsible for various infections.

Morphology of Staphylococci

Spherical (cocci) shaped organisms arranged in irregular clusters resembling grapes.

Gram-positive

Classification indicating that an organism has a thick peptidoglycan cell wall that retains crystal violet dye.

Environmental Resilience

The ability of an organism to withstand extreme conditions such as high salt concentrations and variable pH.

Virulence Factors

Characteristics of a pathogen that enhance its ability to cause disease.

Coagulase

An enzyme produced by Staphylococcus aureus that enables clotting of plasma and evades immune response.

Hyaluronidase

An enzyme that breaks down hyaluronic acid, allowing bacterial spread through tissues.

Staphylokinase

An enzyme that destroys blood clots, facilitating the spread of bacteria.

DNase

An enzyme that degrades DNA, helping the bacteria escape from immune cells.

Lipases

Enzymes that break down lipids, aiding in colonization of skin surfaces.

Penicillinase

An enzyme that inactivates penicillin, contributing to antibiotic resistance.

Hemolysins

Toxins that lyse red blood cells.

Leukocidin

A toxin that destroys white blood cells, weakening the immune response.

Enterotoxin

A toxin that causes gastrointestinal disturbances such as vomiting and diarrhea.

Exfoliative toxin

A toxin that causes the separation of the epidermis, leading to scalded skin syndrome.

Toxic shock syndrome toxin

A superantigen that triggers an excessive immune response.

Localized Infections

Infections that are confined to a specific area, such as folliculitis or boils.

Folliculitis

An infection characterized by inflammation of hair follicles.

Furuncles (Boils)

Infections that progress from folliculitis leading to painful abscess formation.

Carbuncles

Extensive lesions resulting from interconnected furuncles.

Impetigo

A highly contagious skin infection with bubble-like swellings, particularly in children.

Systemic Infections

Infections that affect the entire body or major organ systems.

Osteomyelitis

Infection of bone tissue caused by Staphylococcus aureus.

Bacteremia

The presence of bacteria in the blood.

Endocarditis

Infection of the heart valves or lining, often in those with pre-existing conditions.

Toxogenic Diseases

Diseases caused by toxins produced by bacteria.

Gastroenteritis

Acute gastrointestinal symptoms caused by Staphylococcus aureus enterotoxins.

Scalded Skin Syndrome

Condition caused by exfoliative toxins resulting in skin peeling.

Toxic Shock Syndrome

A life-threatening condition characterized by fever and multi-organ failure.

Antibiotic Resistance

The ability of bacteria to resist the effects of medication previously effective against them.

Treatment Approaches

Methods used to address infections caused by Staphylococcus aureus, often involving antibiotics.

Community-acquired MRSA

Methicillin-resistant Staphylococcus aureus strains acquired in the community, posing public health challenges.

Transition to Streptococcus

Moving from the study of Staphylococcus aureus to the characteristics of Streptococcus species.

Cocci

Spherical bacteria often found in clusters.

Epidemiology

The study of how diseases affect the health and illness of populations.

Infections

Diseases caused by pathogenic organisms.

Symptoms

Signs indicating the presence of disease.

Pathogenesis

The process and development of a disease.

Clustering

The arrangement of certain bacteria in groups or patterns.

Honeycomb lesions

A description sometimes used for carbuncles due to their interconnected nature.

Contagious skin infection

Infections that easily spread from one person to another.

Blood agar plates

A laboratory medium used to culture bacteria and observe hemolysis.

Immune Defenses

The body's mechanisms for preventing infection and disease.

Morbidity

The condition of being diseased or the incidence of illness.

Pre-existing conditions

Health issues that exist before a new diagnosis or infection.

Epidemiologist

A professional who studies and analyzes patterns of health and disease conditions.

Toxin-mediated diseases

Health conditions that arise due to toxins produced by pathogens.

Treatment resistance

The ability of bacteria to withstand drug treatments meant to eliminate them.

Gastrointestinal symptoms

Physical signs of disorders affecting the digestive system.

Cluster growth

A growth pattern characterized by bacteria forming clusters.

Nutritional deficiencies

Lack of essential nutrients that can weaken the immune system.

Health conditions

Medical issues that may increase susceptibility to infections.

Non-invasive infections

Infections that do not penetrate deeply into the body's tissues.

Virulence mechanisms

Strategies used by pathogens to invade and cause disease.

Clinical significance

The importance of a condition in a medical context.

Public health challenges

Issues that affect the health of populations on a large scale.

Environmental versatility

The ability of an organism to adapt to various environmental conditions.

Indications of infection

Signs and symptoms that suggest the presence of an infectious disease.