Exam FINAL: System Diseases Flashcards
This natural defense of the skin creates a tough, waterproof layer
Keratin
This natural defense of the skin allows for new skin every 20-40 days
Skin sloughing
This natural defense of the skin is a low pH, high lipid protector, essentially the same as ear wax
Sebum
This natural defense of the skin is a low pH, high salt defense.
Sweat
This natural defense of the skin is an enzyme that digests the peptidoglycan of bacterial organisms
Lysozyme
Propionibacterium acnes, Corynebacterium spp., Micrococcus spp., Staphylococcus spp., Streptococcus spp., and yeasts are examples of what?
Normal skin flora
This is the organism that causes acne
Propionibacterium acnes
Propionibacterium acnes is Gram positive or Gram negative?
Propionibacterium acnes is Gram +
What does Propionibacterium acnes do?
Digests sebum, attracts neutrophils
How are lesions formed when infected with Propionibacterium acnes?
Neutrophil digestive enzymes caues lesions, or “pus pockets”
This treatment for acne acts by drying plugged follicles and killing microbes. What is a downside of it?
Benzoyl peroxide. It is basically a bleach on your skin.
This is an antibiotic treatment for acne.
Tetracycline
How does Accutane work for acne? What are problems with it?
It inhibits sebum formation. It has many severe side effects. (How is it even legal?!)
What organisms cause impetigo?
Staphyloccocus aureus and Streptococcus pyogenes
This disease is characterized by peeling, crusty skin, and is very contagious.
Impetigo
What disease does SSSS stand for, and what is its cause?
Staphylococcal Scalded Skin Syndrome is caused by Staphylococcus aureus
This non-deadly, but very painful, disease causes large red blisters on the skin that peel off in sheets.
SSSS
Enzymes produced by an organism are _____, or things that allow an organism to produce disease
virulence factors
This is the most treated pathogen currently
Staphylococcus aureus
This is the organism that causes necrotizing fasciitis
Streptococcus pyogenes
Enzymes produced by Streptococcus pyogenes in necrotizing fasciitis cause what action?
Tissue digestion
What may necrotizing fasciitis lead to, as correlated with a drop in blood pressure?
Toxic shock
What is the mortality rate for necrotizing fasciitis? What is the general treatment plan?
30-70% mortality
Surgical removal/amputation of limbs is most appropriate due to the rapid rate of spreading
What organism causes Rocky Mountain Spotted Fever?
Rickettsia rickettsii
What kind of organism is Rickettsia rickettsii?
A gram negative bacillus or coccobacillus
How is Rocky Mountain Spotted Fever spread? Where is it generally found?
Transmitted by tick bites. Mostly found in the Eastern Atlantic states.
What causes the red to black rash seen with Rocky Mountain Spotted Fever? What is happening to to cause this?
Petechiae (hemmorhaging)
The capillaries are degraded by the organism.
Besides the red to black rash, what are 4 symptoms of Rocky Mountain Spotted Fever?
Fever, Chills, Headache, Muscle Pain
What is unique about Rickettsia rickettsii that caused it to be difficult to discover? What kind of parasite is it?
It is an obligate intracellular parasite (needs a host to survive). It does not grow in a culture, therefore was hard to initially discover.
What does Rickettsia rickettsii depend on it’s host for?
It needs to obtain nutrients, NAD+, and CoA from the host, as it does not have it for itself. It uses this to complete cellular respiration.
What binding action does Rickettsia ricketsii have on the host cells, and where does it go?
It binds to cell surface, taken into endothelial cells. It escapes from a phagosome into the cytoplasm.
How is Rocky Mountain Spotted Fever diagnosed?
How is it treated?
Diagnosed using PCR, or other molecular methods
Treated with long course of antibiotics
These are rashes associated with elevated lesions filled with fluid
Vesicular or pustular rash
What was the overall death rate of smallpox, historically? What group of people were more likely to die?
20-80% death rate
Children more likely to die
What disease is the only disease completely eradicated by vaccinations? When was is eradicated?
Smallpox in 1980
What are problems with the vaccine for smallpox?
It’s incredibly harsh, death possible, amputations from infected limb, considered a bioterrorism agent
What virus causes chickenpox?
Varicella-zoster
Where does local infection of chickenpox reside?
In lymph nodes in the neck
What symptoms occur with lymphocyte associated viremia?
Fever, malaise
These are rashes associated with flat to slightly raised colored bumps
Maculo-papular rashes
What are the 2 physical observable symptoms of measles?
Koplik spots and skin rash
What is the worldwide leading cause of vaccine-preventable death among children?
Measles
What is the measles death rate in developed countries? What is it among malnourished children?
1-5%, and 10-30% among malnourished children.
What are examples of health complications from measles?
pneumonia, diarrhea, encephalitis
What happens when a pregnant woman contracts Rubella? What symptoms does it cause?
Congenital Rubella Syndrome causes small birth weight, blindness, hearing loss, mental retardation, heart problems in the infant
What provides restricted entry into the brain for microorganisms, medications, and the immune system?
The blood-brain barrier
This is inflammation of the brain
Encephalitis
This is inflammation of the membranes surrounding the brain and spinal cord
Meningitis
This strain of bacteria causes bacterial meningitis, generally affecting infants and newborns
Haemophilus influenzae type b
This strain of bacteria causes bacterial meningitis, generally affecting children between 1 month-4 years old, and the elderly
Streptococcus pneumoniae
This strain of bacteria causes bacterial meningitis, generally affected college students.
Neisseria meningitidis
True/False: Streptococcus pneumoniae is a Gram + diplococci
TRUE: Streptococcus pneumoniae is a Gram + diplococci
Virulent strains of Streptococcus pneumonia are ___. This means _____.
Encapsulated. This means it has the ability to cause disease.
The subunit vaccine for Streptococcal meningitis acts how?
Induces opsonizing antibody to the capsule of the pathogen
These are immune cells for the brain and CNS (2 ans)
Microglial cells and microphages
How does Neisseria meningitidis enter the body to cause disease?
Enters via droplets through the nasal cavity
How many Americans get meningococcal meningitis from Neisseria meningitidis each year? How many die? How many have long term disabilities resulting?
Meningococcal meningitis (Neiserria meningitidis)
2,500 Americans/year
10-15% die
20% long-term disability
What type of vaccine is used for Neisseria meningitidis and how does it work?
Subunit vaccine that induces opsonizing antibody to capsule
This is the name of the ORGANISM that is also known as the Brain Eating Amoeba
Naegleria fowleri
This is the name of the DISEASE caused by the brain eating amoeba
Naegleria Meningoencephalitis
Where is Naegleria fowleri found?
In fresh, warm water (ponds, ground water, etc)
When do symptoms appear after infection with Naegleria fowleri? What are the symptoms?
3-10 days after exposure.
Severe headache, fever, stiff neck, dementia, coma
What is the route of passage for Naegleria fowleri to infect a human?
Initially up the nose, then makes way into brain
What does Naegleria fowleri do to a human?
Feeds on brain and spinal tissue, destroying it. Death occurs within 10 days.
What is the treatment for Naegleria meningoencephalitis?
There is no treatment. Death is likely (>95% mortality rate)
This is the name of the organism that causes toxoplasmosis.
Toxoplasma gondii
What type of organism is Toxoplasma gondii?
Flagellated protozoan parasite
What is the primary reservoir for Toxoplasma gondii?
Cats
What are two groups of people that are at risk of infection by Toxoplasma gondii?
Pregnant people (fetus at risk) and people with AIDS
What can happen to fetuses that are exposed to Toxoplasmosis infection? (3 ans)
Liver damage, brain abnormalities, blindness
What organism causes Leprosy (Hansen’s disease)?
Mycobacterium leprae
This disease causes change in skin pigmentation, loss of sensation, potentially loss of limbs.
Leprosy (Hansen’s disease)
This animal is a carrier of Mycobacterium leprae.
Armadillo
Where do Mycobacterium leprae multiply and thrive within the body?
In macrophages. They escape the phagolysosome and thrive within these cells.
Is Leprosy treatable? If so, how?
Yes, it is a long, slow treatment process with a drug cocktail
How is rabies virus different from other viruses?
Most viruses have a very narrow window of infection potential, while rabies can infect any mammal
Human “dumb” rabies presents with these symptoms. (5)
Fever, confusion, anxiety, encephalitis, death
Animal “furious” rabies presents with these symptoms. (4)
Wandering, aggression, biting, salivating
What is hydrophobia related to rabies
Fear of water. Perhaps due to inability to swallow saliva
How is rabies diagnosed?
Must be diagnosed post-mortem. Brain biopsy will show plaques in the brain indicative of Rabies infection.
What is the name of the plaques found in the brain of a rabies infected animal?
Negri bodies
What is the treatment and mortality rate of rabies infection in the brain?
There is no treatment once the brain reaches the brain. The mortality rate is nearly 100%
Poliovirus, an “enterovirus” has an ___ ___ shell that protects it from ___.
icosahedra capsid shell that protects it from digestion
What disease is caused by Poliovirus? What are its symptoms?
Poliomyelitis; Paralysis
What is the best way to prevent poliovirius?
Safe, effective vaccine (PV-1,2,3)
What is the name of the organism that causes tetanus?
Clostridium tetani
What is unique aboutu the morphology of the Clostridium tetani cells?
They have a tennis racket shape, sending their spores to one side of the cell to give this appearance
What causes the symptoms of Tetanus once the bacteria makes entry into the host? What symptoms are caused?
The bacterial invasion releases bacterial toxins, causing rigid paralysis.
This is the term for bacteria in the blood.
Bacteremia
This is the term for bacteria that is growing in the blood
Septicemia
This is the term for viruses in the blood
Viremia
In septic shock, the following occurs: ____ release; macrophage ____; ____ blood pressure (leaky capillaries); high ____
endotoxin (LPS) release;
macrophage cytokines;
low BP (leaky capillaries);
high fever
This is an overwhelming systemic response to an infection
Shock
This CV system defense are antimicrobial proteins in lysosomes of phagocytic cells
Defensins
Having infectious agents in the blood will very quickly evolve into ___ ___ due to the connection to everything.
systemic infection
What is the organism that causes “the” Plague?
Yersinia pestis
What type of cell is Yersinia pestis?
Gram negative rod
Where does Yersinia pestis grow?
In the digestive tract of a flea
What is the vector for Plague? What is the reservoir?
Plague vector = flea
Plague reservoir = rodents, prairie dogs
Where is Plague commonly found in the US?
Four corners in AZ
When did the Black Death occur?
1348-1350
The Black Death reduced Europe’s population by about half, or ___ people.
100 million
Which plague was the most common type?
Bubonic plague
Historically, what was the mortality rate for Bubonic plague, and when did death occur?
Up to 80% mortality rate. Death in appx 8 days
Historically, what was the mortality rate for Pneumonic plague, and when did death occur?
90-95% mortality rate.
Death in appx 8 days.
Historically, what was the mortality rate for Septicemic plague, and when did death occur?
Near 100% mortality rate.
Death on first day of symptoms.
Today, what is the mortality rate of Bubonic plague, when treated? When not treated?
1-5% mortality when treated.
50% mortality when not treated.
Today, what is the mortality rate of Pneumonic plague, when treated? When not treated?
5-15% mortality when treated early.
Almost 100% fatal when not treated.
Today, what is the mortality rate of Septicemic plague, when treated? What is a problem with treatment?
50% mortality.
There still is no good treatment
What are the swollen lymph nodes called with Bubonic plague?
Buboes
When Yersinia pestis enters the bloodstream, where does it grow?
In the macrophages in lymph nodes
Borrelia burgdorferi is the organism that causes what disease?
Lyme disease
What shape/type of bacteria is Borrelia burgdorferi?
Gram negative spirochete (motile!)
What is the vector (and its reservoir) to cause Lyme disease in a human by Borrelia burgdorferi?
Lyme disease: Borrelia burgdorferi
Vector: Ticks
Reservoir: Mice, Deer
What occurs during the primary stage of Lyme disease?
Bulls-eye rash on skin
What 2 things occur during the secondary stage of Lyme disease?
Neurological symptoms
Cardiac dysfunction
What occurs during the tertiary stage of Lyme disease?
Lyme arthritis
Inflammation of large joints and ___ occurs with Lyme arthritis
Paraplegia
How is Lyme disease treated? What happens if treatment is delayed?
A long course of antibiotics. Delays in treatment can result in long term neurological damage, wheelchair-bound etc.
What is the name for the disease known as Rabbit fever?
Tularemia
What is the organism that causes Tularemia?
Francisella tularensis
What kind of organism is Francisella tularensis?
Gram negative coccobacillus
What is the reservoir for Francisella tularensis?
Reservoir=Rabbits and small animals
What is the vector for Francisella tularensis? Are there other potential causes?
Vector=Ticks.
Also caused by ingestion of contaminated meat
What symptoms are present with tularemia? (5)
Fever, diarrhea, pain, fatigue, difficulty breathing
What happens if you get tularemia via a bite?
Skin ulcer develops at the bite site
Why is Francisella tularemia considered a bioterrorism agent?
It is extremely infectious, needing as few as 10 organisms to cause disease
Aedes agypti is the cause for what viral infections?
Yellow fever and Dengue fever
What occurs with capillaries and blood with a viral hemorrhagic fever?
Capillary fragility and leakage
Blood clotting system is disrupted, causing hemorrhaging
Why is a viral hemmorhagic fever problematic for the liver? What can it cause?
It damages the liver as it attempts to process the damaged blood cells; Leads to hepatitis
What is the fatality rate for Ebola?
Up to 90%
What are 3 viral hemorrhagic fever diseases?
Yellow Fever
Dengue Fever
Ebola
Yellow fever causes ___-like symptoms. It is ___ (always/sometimes) hemorrhagic.
Flu-like
Sometimes hemorrhagic
Dengue fever causes ___-like symptoms. It is ___ (always/sometimes) hemorrhagic.
Measles-like
Sometimes hemorrhagic.
What is the mortality rate for Yellow fever?
15% mortality rate
What is the mortality rate for Dengue fever?
20% mortality rate (untreated)
2.5% if treated
This viral fever infection is almost always hemorrhagic
Ebola
How do people with Ebola die?
Hypovolemic shock from loss of blood volume
What is the overall mortality rate for Ebola? (generally speaking, not the current outbreaks)
80-90% mortality
What is the approximate mortality in the current outbreak of Ebola?
50% mortality
When was Ebola first found as an emerging disease?
1976
Why do scientists believe fruit bats are such a key player in the lifecycle of Ebola?
They aren’t certain, but fruit bats are the only beings that seem to have antibodies to Ebola, so it is a decent proposal.
What cells are the only ones affected by HIV?
Helper T lymphocytes (CD4+)
What is the name of the skin lesions that affect AIDS patients, covering the skin, esophagus, and other sites.
Kaposi’s Sarcoma
What organism causes Kaposi’s sarcoma?
HHV-8 (Human Herpes Virus-8)
What are the mixed cell tumors caused by HHV-8 made up of?
HHV-8 mixed cell tumors are lymphocytes, fibroblasts, and blood vessels.
AZT is an example of what type of drug?
Nucleoside analog
Nucleoside analogs and protease inhibitors are types of drugs used for what?
HIV infections
How do HIV drugs work?
By blocking reverse transcriptase or inhibiting protease, essentially stopping HIV DNA from being replicated in the patient.
What is a distinct difference between the majority of AIDS cases in the US versus the world?
Nearly half of US cases are obtained via homosexual sex, while the majority of the world’s cases are obtained via heterosexual cases.
What are 4 GI tract defenses in the oral cavity?
Lysozyme, saliva, tonsils, normal flora
What is a GI tract defense located in saliva and in the gut?
Secretory IgA
What are 2 factors in the stomach that are GI tract defenses?
Low pH, mucus
What is the pH of the stomach?
0.5-1.0 pH
What are 4 GI tract defenses located in the intestines?
Bile, GALT, normal flora, and peristalsis
What is a common organism to cause tooth and gum infections?
Streptococcus mutans
What organism causes gastric ulcers?
Helicobacter pylori
According to the CDC, over half of diarrhea outbreaks were caused by what?
Unknown etiology
Of the bacterial diarrhea outbreak cases, what organism is a major cause?
Salmonella
Of the viral diarrhea outbreaks, what viral organism is a major cause>
Norovirus
What was Typhoid Mary a human carrier and reservoir of?
Salmonella typhi
What symptoms present with Typhoid?
Stupor, “Typhoid eyes”
Is Typhoid treatable?
It is fatal
What is the name of the Salmonella serovar that commonly affects people today?
Salmonella enterica
What is the concern with Salmonella and eggs?
It can actually penetrate the egg shell, getting into the yolk of the egg.
What is the concern with Salmonella as far as ease of transmission?
It is very infectious, and only requires as few as 10 organisms for infection.
Was is a key virulence factor with Salmonella?
Attachment/adhesion ability
What kind of organism is Salmonella enterica?
Gram negative bacillus
What two methods are used for Salmonella classification?
Serology (titers); Phage susceptibility assays
How does Salmonella invade epithelial cells?
Motility, LPS, fimbriae
What symptoms are caused by Salmonellosis? (3)
Nausea, cramps, diarrhea
What is the problem regarding the infectiousness of salmonellosis and it’s relatively short reovery time?
One recovers in a few days, but can shed the organism for up to 6 months, contributing to outbreaks
This is exclusively a human parasite, infecting the large intestine
Shigella
What is Shigella also known as?
Dysentery
What is the name of the exotoxin released by Shigella? What does it affect/do?
Shiga-toxin. It affects the intestine, inhibiting protein synthesis of epithelial layer of the large intestine
What is a harmful strain of E. coli, that is mostly a bovine intestinal commensal?
E. coli 0157 H7
What does E. coli 0157 H7 infect?
Large and small intestine
What is the exotoxin produced by E. coli 0157 H7?
Shiga-like toxin
What does shiga-like toxin affect?
Intestines and kidneys
What is the name of the syndrome commonly associates with E. coli 0157 H7, that is usually the cause of death in children?
HUS - Hemolytic uremic syndrome
What is the name of the organism that causes gastroenteritis, commonly associated with chicken slaughterhouses?
Campylobacter jejuni
What kind of organism is Campylobacter jejuni?
Small curved Gram negative rod
Approximately how many cases of Campylobacteriosis occur per year in the US?
2.4 million cases/year
What are the sources of Camplyobacteriosis? (4)
Undercooked poultry, shellfish, unpasteurized dairy products, contaminated water
What are the symptoms of Campylobacteriosis?
Watery/bloody diarrhea, stomach cramps, vomiting
What is a virulence factor of Campylobacter jejuni?
Adhesion to mucosa of the GI tract
What is the treatment for Campylobacteriosis?
Antibiotics
This is the organism that causes Cholera
Vibrio cholerae
What is the toxin released by Vibrio cholerae?
Cholera toxin (CT) A-B toxin
What is unique about Vibrio cholerae and the affect on its host
The bacteria is non-invasive; it never enter the host cells.
How do people die from Cholera?
Dehydration from heavy fluid loss
What is unique about the diarrhea caused by Cholera?
“rice water stools” is a distinct gray fecal water
What is the best treatment for Cholera? What antibiotic is used?
No antibiotics used for Cholera. Treatment focuses on fluid replacement
Who discovered the source of Cholera to be from drinking water?
John Snow in London
What is the mortality rate for treated Cholera? Untreated?
Cholera (Vibrio cholerae)
Treated: <1% mortality
Untreated: 30% mortality
___ made by bacteria in inappropriately stored food can cause acute diarrhea with vomiting
Enterotoxins
This bacterial organism is commonly associated with food-born illness connected to rice.
Bacillus cereus
This bacterial organism is commonly associated with food-born illness connected to meats.
Clostridium perfringes
This bacterial organism is commonly associated with food-born illness connected to meats and salads.
Staphylococcus aureus
This parasitic organism infects the GI tract, and can be found in two forms.
Giardia lamblia
The active form of Giardia lamblia is called a ___.
Trophozite
The hardy form of Giardia lamblia that can exist in the environment is called a ___
Cyst
What makes Giardia lamblia cysts difficult to manage?
They are very durable and insensitive to chlorine
What is the source of infection for Giardia?
Contaminated water
What kind of environment is Giardia lamblia commonly found in?
Cold areas
How does G. lamblia infect its host?
It attaches to the human intestinal wall
What are the symptoms of Giardiasis?
Stomach cramping and diarrhea lasting for weeks
How is Giardiasis treated?
Parasitic drugs
This organism was first identified in 1976, and is associated with contaminated water and fecal-oral contamination/
Cryptosporidium
This organism caused the largest waterborn illness outbreak in US history. What is the organism? When and where was the outbreak?
Cryptosporidium.
1993
Milwaukee
This organism is responsible for the most childhood morbidity and mortality from diarrhea.
Rotavirus
Why are babies at risk for Rotavirus?
Babies that are not breastfed are lacking maternal antibodies
What measures can be taken to help non-nursed babies prevent Rotavirus infections?
MLV vaccine is now available
What is Norovirus commonly referred to as?
Norwalk virus
This organism is the cause of almost all (__%) of acute diarrhea outbreaks in adults, and is associated with cruise ship outbreaks and school closures.
90%
Norovirus
These viral liver infections are associated with fecal/oral route of infection.
Hepatitis A and E
What is the route of infection for Hepatitis B?
Blood borne and STD
What is the route of infection for Hepatitis C?
Blood borne and (other??)
What else can cause hepatitis?
Noninfectious conditions
What is recommended for health professionals, since exposure risk in high in healthcare?
Hepatitis vaccine
What integumentary symptom/sign does hepatitis cause?
Jaundice of the skin
