Bacterial diseases

Rocky Mountain Spotted Fever

Agent: Rikketsia ricketsii

- transmitted through tick bites.

Symptoms; fever, headache, and a spotted rash.

Brucellosis

Agent: Brucella melitensis

Zoonosis- transmitted from animals to humans

-Transmitted through handling of infected animals or unpasteurized milk

Symptoms: Undulant fever, sweating, chills, headache

Whooping Cough

Also known as Pertussis

Agent: Bordatella pertussis

Route of Transmission: Inhalation

Symptoms: Catarrhal stage: common cold

Paroxysmal stage: persistent, violent cough without a breath; wheezing inhalation (whoop)

Convalescent stage: several weeks as coughing subsides
- Cyanosis (blue appearance) due to poor oxygen exchange

-Dangerous to children

— kills cilia in throat causing build up of mucus

Identify the different vaccines used for pertussis

– DTP vaccine had more intense side effects (low patient compliance) (endotoxin)

– DTaP vaccine is now used which causes less intense side effects

•Six doses; doesn’t use the endotoxin

Gonorrhea and (PID)

Agent: Neisseria gonorrhoeae

Transmitted through: Sexual contact or via birth canal to newborns ( through newborns eyes) 

Identify parts of bacteria: capsule and diplococci

Consequence of PID: damage to uterine tubes cause infertility

Pseudomonas aeruginosa infection 

Blue-green pus due to pigment produced by bacteria; under nails 

• Opportunistic pathogen; burns or open skin

Route of Transmission: water borne, direct contact, nosocomial infections

— self limiting (cleared by body) 

Legionnaire’s disease or legionellosis

Agent: Legionella pneumophila

Route of Transmission: Respiratory

HVAC, Spas, showers, Humidifiers, Warm water lines in hospitals

Symptoms: cough, general symptoms of pneumonia

— “Modern” disease due to their preferred environments; Central heating, water lines, etc. (we didn’t always have these) 

Cholera

Agent: Vibrio cholera

Transmitted: through contaminated water or foods

Symptoms: No fever

•Rice-water stool

•Dehydration and hypovolemic shock

Vibrio cholera

Vibrio shape; Flagella is monotrichous

What does cholera toxin do and how does it relate to osmosis? 

-Cholera toxin is important for virulence (causes diarrhea) (shedding of the bacteria into the environment in large amounts)

– The Toxin results in electrolytes leaving the cell and going to the Intestinal lumen. 

— results in lots of water inside the intestine(due to osmosis) that gets passed as diarrhea 

Osmosis: if high concentration of solutes on one side, water rushes across the membrane to balance out that concentration

UTI & Traveler’s diarrhea

Agent: E. Coli

Most common cause for UTIs

Fecal/ Fecal oral for Travelers diarrhea

Describe the flagella on E. coli

Peritrichous flagella; multiple flagella that are distributed randomly over the entire surface of a bacterial cell

Bacillary dysentery

Agent: Shigella dysenteriae

Transmitted through: fecal/oral 

Symptoms: diarrhea and bloody stool

shiga toxin: can secrete, results in the host cells stopping protein synthesis

— more severe case, usually self limiting 

Salmonellosis

Agent: Salmonella species

Transmitted through:  fecal/oral route from chicken eggs

-Their anatomy, poop comes out same hole

Prevention methods: Boil the egg, cook it, peel it, or forget it

Pneumonia

Agent: Klebsiella pneumoniae

Transmitted: inhalation

Symptoms: Coughing and chest pain; Thick bloody sputum- destruction of alveoli (lung tissue), recurrent chills

-Opportunistic pathogen; clearing oral secretions from the respiratory tract helps with preventing lung disease.

Klebsiella pneumoniae

Capsule surrounding the bacilla helps them avoid phagocytosis by the immune system.

Gram - 

Identify the at-risk populations for poor respiratory tract clearance:

Cleaning secretions from respiratory tract helps prevent pulminary disease; some have problems with this

Alcoholics; Compromised immunity like AIDS; Very young or very old

Pneumonic plague

Agent: Yersinia pestis

Transmitted through: inhalation human to human

Symptoms: cough, difficulty breathing, and frothy bloody sputum

Causes pneumonia 

Bubonic Plague (Black plague)

Agent:Yersinia pestis

Transmitted through: flea bite 

Symptoms: smooth, enlarged lymph nodes called buboes (groin, armpit, neck) 

- muscular pain, severe headache, If bacteremia or septicemia happens, you have death of tissues which turn black

Meningitis

Agent: H. influenzae

Transmitted through air 

Signs and symptoms: – Increased white blood cells in cerebrospinal fluid (CSF)

Inflammation of meninges causes severe headache, light sensitivity, nausea, pain

• Loss of brain functions: drowsiness, confusion, irritability

If brain infected, encephalitis (inflammation of the brain)

• Deafness, blindness, drastic changes to patient’s behavior, coma, or death

Food-borne infections

Agent: Campylobacter jejuni
Leading cause of food-borne illness in US

Symptoms: diarrhea, abdominal cramps and fever, no vomiting

• In the intestines, not stomach

C. diff

Agent: Clostridium difficile

Signs and symptoms: 5-10 watery, foul-smelling bowel movements per day

—Inflammation and formation of intestinal lesions called pseudomembranes

Made of connective tissue, dying WBCs, and dead colon cells

Treatments: – Restoring the microbiome

“Modern infection”, increased with the use of antimicrobial drugs

Usually, stopping antimicrobial treatment is enough to restore the normal microbiome

•Probiotics

•Fecal transplants in severe cases

C. Diff

 Intestinal lesions; Made of connective tissue, dying WBCs, and dead colon cells

diptheria 

Pseudomembrane made of:  intracellular fluid, blood clotting factors, leukocytes, bacteria, and remains of dead cells

Tetanus and lockjaw

Agent: Clostridium tetani

Transmitted through: puncture wound

Signs and symptoms: Tightening of the jaw and neck muscles

-Sweating, drooling, grouchiness, and constant back spasms

-Spasms and contractions may increase and spread to cause curled arms, fists, and feet, and the body arches backwards as the heel and back of the head bend towards each other

Botulism

Agent: Clostridium botulinum

Toxin blocks the nerve signal that tells the muscle to contract (acetylcholine)

Gas Gangrene

Agent: Clostridium perfringens (anaerobic)

Symptoms: Intense pain at site of infection; blackening of infected muscle and skin; production of bubbles of hydrogen and CO2

– May break out with a frothy brownish liquid

– necrosis( tissue death) 

Transmitted through contact with broken skin

Diabetics are susceptible

Cutaneous anthrax

Agent: Bacillus anthracis

Bacteria usually shed from an animal makes its way to broken skin; results in eschars or swollen, black, crusty ulcers

Inhalation anthrax

Agent: Bacillus anthracis

Inhalation(most severe from): common cold or flu- sore throat, mild fever, myalgia, mild cough, and malaise

progress to severe coughing, nausea, vomiting, fainting, confusion, lethargy, shock, and death

Impetigo and scalded skin syndrome

Agent: Staphylococcus aureus

Impetigo: small, flattened red patches usually on the face and limbs, usually on children 

-Pus filled vesicles that break, forming a thick honey-colored crust

Scalded skin syndrome: separation of the outer layer of skin by the toxins released by Staphylococcus

Identify which bacteria are commonly associated with methicillin resistance and what measures keep it in check:

Staphylococcus aureus

often become resistant against antimicrobial drugs; usually treated with vancomycin 

—  part of normal flora; a large amount is needed for infection
— Proper aseptic technique and cleansing keeps it in check

Strep throat and Scarlet Fever

Agent: Streptococcal pharyngitis:

Strep throat: inflamed back of pharynx, with swollen lymph nodes and purulent abscesses covering the tonsils; pain during swallowing; bad breath 

•Scarlet fever- rash that begins on the chest and spreads through the body- tongue becomes strawberry read

Streptococcus pyogenes

Streptococci shape (round and in strings)

Necrotizing Fasciitis

Agent: S. pyogenes

Early: Hot, intensely painful sunburn-like rash

•Disproportionately more pain than how the rash appears

As it progresses:

•Fever, tiredness, muscle aches

•As tissue is destroyed, blood pressure drops, and patient becomes mentally confused and ultimately comatose

Endocarditis

Endocardium lines the heart chambers, valves, and vessels near the heart

-Bacteria along the linings trigger inflammation and the formation of vegetations

Vegetations- bulky masses of platelets and clotting proteins that surround the bacteria

Complications: IV drug use; Heart abnormalities; Suppressed immune system; 

Increases risk for strokes as the vegetation can break off ( interrupt blood flow through brain)

Listeriosis

Listeria monocytogenes

Transmitted: Foodborn or in utero Cold          —Tolerance can allow the bacteria to survive and proliferate in refrigeration (Bluebell listeria)

• complications that can result in fetuses that contract listeriosis:

abortion, stillbirth, bacterial meningitis

Tuberculosis

Agent: Mycobacterium tuberculosis

Acid fast- Cell walls contain mycolic acid, a waxy lipid

Grows slowly; Survive phagocytosis from immune cells; Can grow inside cells; 

Resistant to Gram stains, detergents, common antimicrobial drugs, and drying out

Explain how tuberculosis can result in tubercles

Macrophages call in more immune cells, causing a tubercle

Tightly packed macrophages surround the site of infection, forming a

tubercle over a two- to three-month period.

Diptheria

Agent: C. diptheriticae

C. diptheriticae has a lysogenic phage that codes for the diptheria toxin

Symptoms: sore throat fever pain

Pseudomembrane: intracellular fluid, blood clotting factors, leukocytes, bacteria, and remains of dead cells

Explain where diptheria gets the ability to make diptheria toxin from

C. diptheriticae has a lysogenic phage that codes for the diptheria

Toxin: Prevents polypeptides from being made and causes cell death 

bacterial vaginitis/vaginosis

Agent: Gardnerella vaginalis, 

Signs and symptoms: White vaginal discharge with a “fishy” odor; Itching and irritation of the vaginal opening;

Clue cells differentiate from vaginal candidiasis

Trachoma

Agent: Chlamydia trachomatis

Sign and symptoms: Scarring of the conjunctiva and cornea;

 Eyelashes turn inwards, cornea is scratched and irritated by the eyelashes

genital chlamydia

Agent: Chlamydia trachomatis

(Asymptomatic in women) Damage to reproductive tissues can cause sterility

– Pelvic inflammatory disease (PID) 

Lymphogranuloma venereum- transient genital lesion at the site of infection

•Followed by development of bubo

syphilis

Agent: T. pallindum

Primary phase: Small, painless, hard lesion known as a chancre (ulceration)

•Often unobserved

Secondary phase:

Widespread rash, sore throat, headache, mild fever, malaise, myalgia

Latent phase : usually ends here;antimicrobial drugs 

.Tertiary phase: years later, untreated patients experience dementia, blindness, paralysis, heart failure, or syphilitic gummas( tumor like growth)

Lyme disease

Signs and symptoms: Bulls-eye lesion

Early: bulls-eye lesion, headaches, dizziness, stiff neck, severe fatigue, chills

Middle: 10% of patients experience neurological symptoms and cardiac dysfunction

Final: 80% of patients experience severe arthritis (may last years); rarely fatal

Vector: deer tick