BIO140 - Gram Negative Bacteria

Rickettsia rickettsii (Rocky Mountain Spotted Fever)

- Rod shaped coccobacillus

- Vector: tick

- Reservoir: dogs, rodents

- S/S: Fever, muscle aches, joint pain, confusion, small red spots on wrists, hands, and soles of feet

Bordetella pertussis (whooping cough)

- Coccobacillus

- Encapsulated

- Obligate aerobe

- Attaches to and kills ciliary cells

- S/S: severe coughing, leads to vomiting

Legionella pneumophila (Legionnaires' Disease)

- Coccobacillus

- Multiplies in macrophages

- Found in streams, warm water pipes, cooling towers

- Atypical pneumonia

- S/S: high fever, cough, headache, chest pain

Burkholderia cepacia

- Nosocomial infections

- Common in Cystic Fibrosis (CF) patients

- S/S: recurrent fever, pneumonia, bacteremia

Pseudomonas aeruginosa

- Rods with polar flagella

- Opportunistic pathogen

- Antibiotic and disinfectant resistance

- Diseases: UTIs, Otitis externa, dermatitis, burn/wound infections, Pneumonia

Haemophilus influenzae

- Very small rod

- Cultures on chocolate agar

- Diseases: Epiglottitis, Meningitis, Adenoiditis, Pneumonia, Conjunctivitis, Otitis Media, Sinusitis

E. coli

- Rod

- Peritrichous flagella

- Facultative anaerobe

- Coliforms

- Many strains are harmless commensals

- Pathogenic strains have specialized fimbriae for attachment, may also produce exotoxins

- Diseases: Gastroenteritis (Traveler's Diarrhea), Hemolytic-Uremic Syndrome (HUS), UTIs

Shigella spp. (Shigellosis)

- Rod

- Peritrichous flagella

- Facultative anaerobe

- Common in unsanitary drinking water

- Small infective dose

- AB toxin damages blood vessels causing dysentary

- S/S: severe diarrhea, abdominal cramping fever

Salmonella enterica (Salmonellosis)

- Rod

- Peritrichous flagella

- Facultative anaerobe

- Bacterial infection (12-36hr incubation period)

- Found in tracts of animals

- Abx use is ineffective

- S/S: fever, nausea, cramping, pain, diarrhea, septic shock

Salmonella enterica serotype Typhi (Typhoid Fever)

- Rod

- Peritrichous flagella

- Facultative anaerobe

- Bacteria multiply and spread through phagocytes

- 2-3 week incubation time

- 1-3% become carriers after infection (shed through feces)

- Vaccine available

- S/S: high fever, continual headache, diarrhea

Proteus mirabilis

- Rod

- Peritrichous flagella

- Facultative anaerobe

- Found in nature

- Diseases: UTIs, wound infections

Yersinia pestis (The Plague)

- Rod

- Vector: Fleas

- Reservoir: rats, ground squirrels, prairie dogs

- S/S: bacterial growth in blood/lymph, bacteria in the lungs, septic shock

Camplyobacter jejuni

- Curved rod

- Polar flagellum

- Heat labile (sensitive) toxins

- Leading foodborne illness

- Transmission: retail poultry, milk, reed meant, person-to-person contact

- S/S: fever, cramping, diarrhea, dysentery

Helicobacter pylori

- Rod

- Bismuth prevents bacterial growth

- Stomach and Duodenal ulcers

- Type O blood is more susceptible to ulcers

Chlamydia trachomatis

- Coccoid

- Obligate intracellular pathogen

- Diseases: Nongonococcal urethritis (inflammation or urethra), Inclusion conjunctivitis, infant pneumonia, Trachoma (largest infectious cause of blindness in the world), can lead to PID

Neisseria gonorrhoaea (Gonorrhea)

- Diplococci

- Diseases: Opthalmia neonatorum, systemic joint infections, STI

- S/S: painful urination, yellow discharge, can result in ectopic pregnancies if it passes the cervix

Neisseria meningitidis (meningococcal meningitis)

- Cocci

- Aerobe

- Encapsulated

- 10% of people are healthy nasopharyngeal carriers

- Begins as throat infection, rash

- S/S: stiff neck, headache, vomiting, nausea, convulsions, coma, death

Vibrio cholerae

- Curved rod

- Produced exotoxin (enterotoxin)

- Causes bacterial intoxication

- Cells lyse, leading to loss of fluids/electrolytes

- Associated with salty brackish water, common with poor water sanitation

- S/S: gastroenteritis (diarrhea, cramping, vomiting, etc.)

Borrelia burgdorferi (Lyme Disease)

- Spirochete

- Vector: tick

- Reservoir: field mice, deer

Stages:

(1) bull’s eye rash, low-grade fever, aches, itching

(2) irregular heartbeat, encephalitis, arthritis (late onset)

(3) neurological and cardiac damage

Treponema pallidum (Syphilis)

- Spirochete

- Blind, multiply, and penetrate capillaries, move into circulation and body becomes incubation site

- Tx w/ penicillin

Stages:

(1) primary, small hard painless lesions (chancre)

(2) secondary, disseminated rash on skin and mucous membranes, hair loss, fever

(3) tertiary, gummas lesions, neurological disorders (paralysis, blindness, deafness, dementia)