Bacteriology Bacteria

Staphylococcus aureus

skin infection + scalded skin syndrome, TSS, food poisoning

MRSA

Methicillin-resistant Staphylococcus aureus

MSSA

Methicillin-susceptible Staphylococcus aureus

VISA

Vancomycin-intermediate Staphylococcus aureus

VRSA

Vancomycin-resistant Staphylococcus aureus

Viridans streptococci

infective endocarditis = bacteria from open mouth wounds (dental procedures) get circulated into the blood —> inflammation of heart lining

Neisseria (morphology)

gram-negative, coffee bean-shaped diplococci

Neisseria gonorrhoeae (transmission & prognosis)

women can be asymptomatic (ectopic pregnancy), infected mothers → neonates, infected males → urethritis

Treatment for Neisseria gonorrhoeae

Ceftriaxone, Gentamicin, Azithromycin

Neisseria meningitidis (progression of diease)

mucous membranes → blood → CNS

causes Waterhouse-Friderichsen syndrome (adrenal gland failure, intravascular coagulopathy)

Neisseria meningitidis

Bacillus anthracis (transmission)

spores —> cutaneous exposure → Cows, Camels and Sheep; Humans as accidental hosts

what has 3 exotoxins —> edema?

Bacillus anthracis

Listeria (morphology)

gram-positive, catalase-positive rod (diphtheroid)

Listeria (lab morphology)

β-hemolysis on blood agar plates

Listeria monocytogenes transmission

contaminated food, unpasteurized cheese | mother → fetus

Listeria monocytogenes (progression of disease)

ingestion leads to septicemia and meningitis in young, old, and immunocompromised

Trimethoprim-sulfamethoxazole

penicillin allergy substitute

Corynebacteria

Non–spore-forming rods, gram-positive bacteria

Corynebacteria diphtheriae prognosis

inhalation of respiratory droplets —> lysogenic bacteriophage-encoded diphtheria toxin → systemic effects (toxemia) : myocarditis, kidney damage

toxemia (function)

• Inhibition of protein synthesis

• Local tissue damage and pseudomembrane formation

DPT vaccine

(diphtheria, pertussis, toxoid)

CLOSTRIDIUM morphology

Gram-positive, anaerobic, spore-forming rods, ubiquitous in soil

Clostridium tetani (prognosis)

exotoxin secreted → nervous system disruption → skeletal muscle contraction → death by respiratory failure

Clostridium botulinum (what happens in disease stage)

exotoxin blocks release of Acetylcholine leading to flaccid Paralysis.

how do infants get botulism

honey

where do Clostridium botulinum spore generate?

anaerobic food environments

Clostridium difficil

Normal intestinal flora, opportunist when antibiotics kill off other normal flora allowing it to proliferate.

Actinomyces are:

Gram-positive, obligate anaerobes, reside in the mouth and intestinal tract

Actinomycosis

abscess formation and swelling at the site of

infection

actinomycosis (associated with)

A. israelii

Escherichia coli

Normal flora of the intestinal tract | Vitamin K production in the large intestine

Endotoxin

Lipopolysaccharides → septic shock

Enteropathogenic E. coli (EPEC)

infant diarrhea | non-bloody diarrhea

Enterotoxigenic E. coli (ETEC)

Traveler's diarrhea

Enterohemorrhagic E. coli (EHEC) is associated with?

Serotype O157:H7

Shigella (shiga toxin)

(entero, neuro, cyto) + Inhibition of protein synthesis

Salmonella Typhimurium

Gastroenteritis

Salmonella Enteritidis

Enterocolitis (inflammation of both intestines @ once)

Salmonella Typhi

SPECIFIC TO HUMANS + Typhoid (enteric) fever

treatment for salmonella typhi

Ciprofloxacin, Ceftriaxone

Yersinia pestis (V and W antigens)

inhibition of phagocytosis

Yersinia pestis (exotoxin)

inhibition of electron transport chain function

Haemophilus influenzae

common cause of secondary respiratory infections following influenza

Bordetella pertussis (transmission)

INH of droplets —> destruction of ciliated epithelial cells in trachea and bronchi

Bordetella pertussis (aka)

WHOOPING COUGH

pertussis toxin (exotoxin) function

increased intracellular cAMP; disruption of host cell functions

tracheal cytotoxin function

damage and loss of ciliated epithelial cells

filamentous hemagglutinin (FHA) function

bacterial adherence to respiratory epithelial cells

Vibrio cholerae (aka)

CHOLERA

Vibrio cholerae (progression of disease)

severe diarrhea with a rice-water color and consistency

treatment for Vibrio cholerae

Doxycycline or Tetracycline

how do you get Campylobacter jejuni

transmission: undercooked food or drinking contaminated milk or water.

Helicobacter pylori

urease (ammonia + CO2) —> Gastric mucus layer or epithelial lining of stomach —> ulcers

P. aeruginosa and P. maltophilia

80% of opportunistic infections by pseudomonads

Acinetobacter baumannii

Major agent leading to pneumonia and meningitis.

Acinetobacter baumannii (special populations)

individuals with weak immune systems, chronic lung disease, or diabetes more susceptible to infection

Acinetobacter baumannii accounts for:

80% of Hospital-acquired infections (HAIs) of the skin and open wounds

Fusobacterium nucleatum:

usually in GI tract, opportunistic leading to severe infections

Fusobacterium nucleatum causes

pleuropulmonary infections, Sinusitis, Oral cavity infections, major contributor to gingivitis

Treponema pallidum (aka)

syphillis

Treponema pallidum (transmission)

motile spirochete → through sexual contact

Treponema pallidum (primary)

chancre (ulcerative inflammatory lesion) in genital region

Treponema pallidum (secondary)

maculopapular rash (like eczema)

Treponema pallidum (tertiary)

granulomatous lesions, CNS involvement (neurosyphilis

Borrelia burgdorferi (aka)

LYME DISEASE

Borrelia burgdorferi (transmitted)

TICKS

Borrelia burgdorferi (visualization)

“Bull’s-eye” red rash

Rickettsia rickettsii (prognosis)

infect WBCs —> blood-borne disseminated infections of endothelium and vascular smooth muscle.

Rickettsia rickettsii (transmission)

bacteria found on ticks, lice, fleas (arthropod vectors)

Rickettsia rickettsii (aka)

Rocky Mountain spotted fever (rickettsial pox)

Mycobacterium leprae (aka)

leprosy (Hansen disease)

Mycobacterium leprae (progression of disease)

grows on skin and superficial nerves, infecting macrophages and Schwann cells.

Tuberculoid Leprosy

Strong cell-mediated immunity; granuloma formation

Lepromatous Leprosy

Weak cell-mediated immunity; numerous bacilli in foamy macrophages

Which leprosy has a positive lepromin test?

Tuberculoid Leprosy

Which leprosy has a negative lepromin test?

Lepromatous Leprosy

transmission: INH (respiratory) or (soil → open wounds) cutaneous

Nocardia

Nocardia (prognosis)

Invasive pulmonary disorder and may lead to brain abscess; 20% of cases cellulitis

C. parvum is:

resistant to chlorine and can be spread in pool water.

Prebiotics

High-fiber substrates for beneficial gut microbiota

Probiotics

Live microorganisms with potential health benefits (no FDA-backed claims)

Postbiotics

Bioactive metabolites/byproducts of microbial activity

examples of Postbiotics

Short-chain fatty acids (SCFAs): support gut health and beneficial microbiota growth

what is Fecal Microbiota Transplantation?

“poop pills” aka healthy human donor stool to a patient with a GI infection

Fecal Microbiota Transplantation (oral pill)

Vowst

Fecal Microbiota Transplantation (rectal suspension administered as an enema)

REBYOTA

agents for cell wall synthesis inhibition?

• β-Lactams (Penicillins, Cephalosporins)

• Vancomycin

how do B-lactams inhibit cell wall synthesis?

inhibition of peptidoglycan cross-linking/polymerization

agents of protein synthesis inhibition?

Aminoglycosides, Tetracyclines

Macrolides (Erythromycin, Clarithromycin, Azithromycin)

Chloramphenicol, Clindamycin

what agents disrupt the cell membrane?

Polymyxins

Amphotericin B, Azoles (antifungals)