Gram Negative Bacteria B Flashcards
Neisseria Species
Gram Negative
Aerobic Diplococci
sex pili, non motile
Neisseria gonorrhoeae
Gram neg cocci
Gonorrhea
NON capsulated
Neisseria meningitidis
Meningitis
Encapsulated
Gram neg cocci
How is gonorrhea transmitted?
Between humans through intimate contact of mucous membrane
pyogenic in Neisseria gonorrhoeae
pus like discharge containing polymorphonuclear leukocyte
Which antibiotic is recommended to N. gonorrhoeae and why?
Cephalosporins because it is resistant to several antibiotics
Symptoms of N. gonorrhoeae in males
urethral like discharge, prostatitis and periurethral abscess
Symptoms of N. gonorrhoeae in females
vaginal discharge, abdominal pain, abnormal menstrual bleeding
Enterobacteriaceae characteristics
gram negative rods; most pathogenic and encountered
Glucose fermenters, oxidase negative
Haemophilus influenzae
Normal microflora of upper respiratory tract
What can H. influenzae cause? (3)
Otitis media
Sinusitis
Bronchitis
large gram negative rods of Enterobacteriaceae are associated with
intestinal infections, found in almost all natural habitats
what does Enterobacteriaceae cause?
Meningitis, bacillary dysentery, typhoid and food poisoning
Treatment of H. influenzae
Quinolones, Aminoglycosides, Cephalosporins
Which bacteria is most common cause of acute bacterial meningitis in infants and young children?
H. influenzae
E. coli is the number one
cause of UTIs
What diseases are E. coli linked to?
pneumonia, meningitis and traveler’s diarrhea
Pseudomonas aeruginosa
Opportunistic gram negative
Strictly aerobic
Catalase positive rod
Glucose/lactose non fermenters
What does E. coli produce from undigested material in the large intestine?
Vitamin K
Endotoxin of E. coli leads to
severe cases of diarrhea
Treatment for E. coli
do not place on antibiotics due to severe shock
the only exception - UTI - amoxicillin/augmentin, cephalosporins, Macrobid and sulfa drugs
Shigella dysenteriae
characteristics
gram negative rod, facultative anaerobe
Lactose non fermenter
toxin in Shigella dynsenteriae
shiga toxin
potent A-B type toxin with 1 A and 5 B subunits
The shiga toxin
prohibits protein synthesis and leads to cell death
Treatments for shigella dysenteriae
sulfamethoxazole, trimethoprim, azithromycin and ciprofloxacin
What does shigella dysenteriae lead to?
diarrhea and fever (dysentery)
Transmission of salmonella
through uncooked meats and eggs
Chickens are the main reservoir
What does Salmonella lead to?
Intestinal infection: diarrhea, vomiting, chills, headache
2 types of Salmonella bacteria
S. typhimurium and S. enteritidis
S. typhi
only carried in humans
causes typhoid fever
Lactose non fermenter
typhoid fever symptoms
fever, diarrhea, and inflammation of the infected organs
treatment of typhoid fever
cipro, ceftriaxone, bactrim and amoxil
Edwardsiella tarda characteristics
produces hydrogen sulfide, found in aquatic animals and reptiles
What does Edwardsiella Tarda cause?
gastroenteritis and wound infections
Two forms of Citrobacter and what they cause
C. freundii - can cause diarrhea and extra intestinal infections
C. diversus - meningitis in newborns
An example of Serratia
Serratia marcescens
what does S. marcescens cause?
can cause UTIs, wound infections and pneumonia
Klebsiella pneumoniae characteristics
large, non motile, produces large sticky colonies in nutrient media, heat stable enterotoxin, R plasmids
Klebsiella pneumoniae is common in
hospitals (pneumonia and UTIs)
Kliebeslla is second only to
E. coli that causes UTIs
R plasmids
confers resistance to ampicillin; can be transferred to enteric bacteria
Treatment for Klebsiella pneimoniae
Quinolones, AMinoglycosides and Cephalosporins
Enterobacter characteristics
similar to Klebsiella but ornithine positive, part of the normal flora, can cause opportunistic infections, highly motile
Two types of Enterobacter and what they cause
E. aerogenes and E. cloacae
both cause UTI and URI (NO DIARRHEA)
Treatment for Enterobacter
Penicillins, aminoglycosides, Bactrim
What does Proteus cause?
UTI infections and hospital acquired infections
Proteus ( P. Mirabilis, P. Vulgaris)
gram neg, lactose non fermenter, oxidase negative, aerobes, highly motile, forms swarming colonies
Treatment for Proteus
broad spectrum penicillins or cephalosporins
Morganella (M. Morganii) causes
UTI infections, wound infections and diarrhea
Treatment for Morganella
Chloramphenicol
Enterobacteriales lactose fermenters (4)
Escherichia coli
Citrobacter spp.
Klebsiella spp.
Serratia spp.
Enterobacteriales Lactose non fermenters (6)
Morganella
Proteus
Providencia
Salmonella
Shigella
Yersinia
What does Pseudomonas aeruginosa cause?
Wound infections
Meningitis
Abscesses
Burns
Septicemia
Treatment of P. aeurginosa
Two antibiotics at once due to resistance
Gentamicin, Ticarcillin/Clavulanate
Vibrios and Curved Rods
Gram negative, facultatively anaerobic, bacillus
V. cholerae type responsible for cholera epidemic
‘O’-somatic Ag
Cholera
Acute, diarrheal illness
How do you get cholera?
Contaminated water and food with feces
Raw shellfish
Legionella pneumophila
Gram negative, intracellular parasites, motile, rod or coccoid shaped, aerobic, use amino acids for energy
Diseases associated with L. pnemonphila
Legionnaires’ Disease
Pontiac Fever
Respiratory transmission-pneumonia
Treatment of L. pneumophila
Penicillins or aminoglycosides
Spirochaetes
Treponema, Borrelia, Leptospira
Treponema pallidum
motile, gram negative, microaerophilic spirochaetes, do not survive well outside of host
How is treponema pallidum transmitted?
Direct sexual contact
Mother to fetus
Not highly contagious
Common inoculation sites of treponema pallidum
Cervix or vagina
Penits
Primary disease process of treponema pallidum
Invasion of mucous membrane
Rapid multiplication
Wide dissemination through lymphatics
Systemic circulation prior to development of lesion
Primary lesion of Syphilis
Resolved by fibrotic walling-off
Secondary lesion of Syphilis
Highly contagious
Host enters latent period
Tertiary syphilis
Localized dermal cancer-like lesions few organisms are present and reflects immunologic reaction of host
Jarisch-Herxheimer
Symptoms of fever, muscle pains, headache, tachycardia
Caused by cytokines released by immune system in response to lipoproteins released from rupturing syphilis
Treatment of Syphilis
IM injection of penicillin
Penicillin G & Azithromycin
Borrelia recurrentis
Relapsing fever (tick, famine)
Treatment of Borrelia recurrentis
Penicillins, Tetracylines, Macrolides
Borrelia burgdorferi
Lyme Disease
Three stages of Borrelia burgdorferi
- Unique skin lesion with general malaise
- Subsequent stage have neurological or cardiac involvement
- Migrating episodes of non-destructive arthritis transmitted by hard body ticks
Treatment of Borrelia burgdorferi
Acute illness with phenoxymethylpenicillin or tetracycline
Leptospira interrogans causes
Weil’s disease
Acute febrile jaundice and nephritis
How is Leptospira interrogans transmitted?
To humans from variety of animal hosts
What does Leptospira interrogans infect?
Infects kidneys and organisms are shed in urine, with renal failure and death not uncommon
Acinetobacter baumanii
Gram negative rod, opportunistic
War against antibiotic resistant pathogens
Treatment of Acinetobacter baumanii
Penicillin
Enterobacteriae lactose fermenters
E. Coli, Klebsiella, citrobacter and serratia
What leads to an increase in N. gonnorhoeae?
Birth control pills - change the pH leads to inc infection
E. coli strains with potentially lethal toxins (5)
O157:H7, O121, O145, O26, O104:H21
Why do we not treat E. coli with antibiotics
endotoxin from dead E. coli leads to endotoxemia
difference between dysentery and diarrhea
dysentery has presence of erythrocytes, don’t go as often as diarrhea
salmonellosis
inflammation of the intestine caused by Salmonella
Paratyphoid fever
similar tot typhoid; caused by S. paratyphi A,B or C
P. mirabilis
proteus, causes UTI and wound infections
Hib
haemophilus influenzane type B; causes virtually all human disease
Pseudomonas aeruginosa characteristics
blue green pigment pyocyanin
catalase positive rod
strictly aerobic
opportunistic
can grow without nutrition
Pseudomonas aeruginosa produces
an extracellular protease which aids to its virulence
what serogroup of vibrio is responsible for classic epidemic cholera
O1 and O139