4C Microbio

Pseudomonas aeruginosa

Frequent contaminant of ventilators, intravenous solutions, and anesthesia equipment

Pseudomonas aeruginosa

Opportunistic pathogen

Pseudomonas aeruginosa

Motile and forms biofilms

Pseudomonas aeruginosa infections

Nosocomial infections, septicemia, burn infections, infections in cystic fibrosis patients

Healthy people and Pseudomonas aeruginosa

Can cause rashes, UTIs, and ear infections from hot tubs, swimming pools, sponges, and washcloths

Francisella tularensis

Causes tularemia

Tularemia reservoirs

Rabbits and rodents

Tularemia symptoms

Ulcerative skin lesions, swollen lymph nodes, conjunctivitis, sore throat, intestinal disruption, pulmonary involvement

Bordetella pertussis

Causes pertussis (whooping cough)

Pertussis transmission

Inhaled respiratory droplets or aerosols

Pertussis virulence factors

Adhesion molecules and toxins that destroy ciliated cells

Catarrhal stage

Nasal drainage and congestion

Paroxysmal stage

Recurrent, persistent coughing

Pertussis vaccine

DTaP

Legionella pneumophila

Causes Legionnaire's disease and Pontiac fever

Legionnaire's disease

Pneumonia

Pontiac fever

Cough, diarrhea, abdominal pain

Legionella sources

Tap water, cooling towers, spas, ponds, air-conditioning vents

Escherichia coli

Most common Enterobacteriaceae organism

Anaerobes to E. coli ratio

9:1 in the intestine

Escherichia coli

Causes about 80% of urinary tract infections

Enterotoxigenic E. coli (ETEC)

Causes traveler's diarrhea

ETEC toxins

Heat-labile toxin (LT) and heat-stable toxin (ST)

LT and ST toxins

Increase secretion and fluid loss causing severe diarrhea

Enteroinvasive E. coli (EIEC)

Causes dysentery-like disease

Enteropathogenic E. coli (EPEC)

Causes infantile diarrhea

Enterohemorrhagic E. coli (EHEC) O157:H7

Causes hemorrhagic colitis

Hemolytic uremic syndrome (HUS)

Severe kidney damage caused by EHEC O157:H7

Klebsiella pneumoniae

Opportunistic pathogen and normal flora

EHEC transmission

Undercooked beef, unpasteurized milk, contaminated beef products

Opportunistic Enterobacteriaceae genera

Enterobacter, Serratia, Klebsiella, Hafnia, Citrobacter, Proteus, Providencia, Morganella, Edwardsiella

Gram-negative rod virulence factor

Lipopolysaccharide (LPS) endotoxin

Salmonella typhi

Causes typhoid fever

Typhoid fever mechanism

Invades small intestine causing ulcerations, perforations, and septicemia

Typhoid fever symptoms

Fever, abdominal pain, alternating diarrhea and constipation

Salmonella enterica

Causes gastroenteritis (food poisoning)

Gastroenteritis

Inflammation of the stomach and intestines causing vomiting and diarrhea

Shigella

Causes shigellosis (bacillary dysentery)

Bacillary dysentery symptoms

Severe abdominal cramps with bloody, mucus-filled diarrhea

Shigella endotoxin

Causes fever

Shigella enterotoxin

Damages mucosa and villi

Salmonella vs. Shigella

Salmonella invades the small intestine and bloodstream; Shigella stays in the large intestine

Yersinia enterocolitica

Found in wild and domestic animals, especially pork

Yersinia pestis

Causes plague

Yersinia pestis reservoirs

Fleas, mice, and other rodents

Plague transmission

Flea bites or aerosols from rodents

Forms of plague

Bubonic, septicemic, pneumonic

Bubo

Swollen, necrotic lymph node

Haemophilus influenzae

Causes meningitis, otitis media, bronchitis, and epiglottitis

Haemophilus influenzae

Does not cause influenza

Hib vaccine

Prevents Haemophilus influenzae type b meningitis

Haemophilus influenzae source

Healthy carriers

Meningitis symptoms

Stiff neck, fever, chills, fatigue, nausea, vomiting, confusion

Haemophilus influenzae aegyptius

Causes pinkeye

Pinkeye transmission

Contaminated fingers, shared personal items, gnats, and flies

Treponema pallidum

Causes syphilis

Syphilis reservoir

Humans

Syphilis transmission

Sexual contact, placenta, laboratory or medical accidents

Primary syphilis

Chancre appears then disappears

Primary latency

Healed chancre with few symptoms

Secondary syphilis

Rash, mucous membrane lesions, hair loss, fever, swollen lymph nodes

Latent syphilis

Mostly asymptomatic

Tertiary syphilis

Nervous system and cardiovascular damage with gummas

Borrelia burgdorferi

Causes Lyme disease

Lyme disease transmission

Ixodes tick bite

Early Lyme disease

Erythema migrans (bullseye rash)

Late Lyme disease

Facial palsy and polyarthritis

Erythema migrans

Bullseye rash

Vibrio cholerae

Causes cholera

Rice-water stools

Characteristic diarrhea of cholera

Cholera toxin (CT)

Enterotoxin responsible for cholera symptoms

Best initial cholera treatment

Rehydration therapy with water and electrolytes

Cholera vaccine

Available for travelers and people in endemic areas

Campylobacter jejuni

Spread by contaminated water, milk, meat, and chicken

Helicobacter pylori

Causes about 90% of duodenal ulcers

Helicobacter pylori

Associated with stomach cancer

Rickettsia prowazekii

Causes epidemic louse-borne typhus

Rickettsia rickettsii

Causes Rocky Mountain spotted fever

Chlamydia trachomatis

Causes ocular trachoma

NGU

Non-gonococcal urethritis

Chlamydia complications in women

Cervicitis, endometritis, salpingitis, pelvic inflammatory disease

Elementary body (EB)

Infectious form of Chlamydia

Reticulate body (RB)

Noninfectious, actively dividing form

Gardnerella vaginalis

Causes bacterial vaginosis

Clue cell

Epithelial cell covered in bacteria

Mycoplasma

Lacks a true cell wall

Mycoplasma pneumoniae

Causes primary atypical pneumonia

Dental caries factors

Sugar, microbes, and acid

Common dental disease bacteria

Streptococcus mutans, Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Fusobacterium, Bacteroides, Prevotella, Treponema

Trench mouth

Acute necrotizing ulcerative gingivitis

Trench mouth bacteria

Treponema vincentii, Bacteroides forsythus, Fusobacterium

Pseudomonas aeruginosa

Common inhabitant of soil and water

Pseudomonas aeruginosa

Normal intestinal flora in about 10% of people

Pseudomonas aeruginosa high-risk patients

Severe burns, neoplastic disease, premature birth, and cystic fibrosis

Legionella pneumophila transmission

Spread by aerosolized water

Enterobacteriaceae

Includes both normal flora and true pathogens

Traveler's diarrhea

Caused by Enterotoxigenic E. coli (ETEC)

Dysentery

Invasion and ulceration of the mucosa of the large intestine

Klebsiella pneumoniae

Common opportunistic cause of pneumonia, UTIs, wound infections, and septicemia

Yersinia pestis today

Still just as virulent as strains from the past