Gram positive bacteria: Difference between revisions

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#Clusters ([[Staph Species]])
#Clusters ([[Staph Species]])
##Coagulase Positive: [[Staph aureus]]
##Coagulase Positive: [[Staph aureus]]
###Always consider a blood culture positive for Staphylococcus aureus to be true bacteremia (and not a contaminant) due to the danger of delaying treatment<ref>Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp</ref>
###Always consider a blood culture positive for Staphylococcus aureus to be true bacteremia (and not a [[Bacteremia Versus Contaminated Blood Cultures‎|contaminant]]) due to the danger of delaying treatment<ref>Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp</ref>
##Coagulase Negative:  
##Coagulase Negative:  
###[[Staph epidermidis]]
###[[Staph epidermidis]]
####Most common cause of catheter-related bacteremia<ref>Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp</ref>
####Most common cause of catheter-related bacteremia<ref>Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp</ref>
####Most common skin contaminant found in blood cultures<ref>Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp</ref>
####Most common skin [[Bacteremia Versus Contaminated Blood Cultures‎|contaminant]] found in blood cultures<ref>Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp</ref>
###[[Staph saprophyticus]]
###[[Staph saprophyticus]]
####[[UTI]]s in women
####[[UTI]]s in women

Revision as of 07:06, 22 April 2014

Cocci

  1. Clusters (Staph Species)
    1. Coagulase Positive: Staph aureus
      1. Always consider a blood culture positive for Staphylococcus aureus to be true bacteremia (and not a contaminant) due to the danger of delaying treatment[1]
    2. Coagulase Negative:
      1. Staph epidermidis
        1. Most common cause of catheter-related bacteremia[2]
        2. Most common skin contaminant found in blood cultures[3]
      2. Staph saprophyticus
        1. UTIs in women
      3. Staph lugdunensis
        1. Rare cause of endocarditis, meningitis, and Skin and Soft Tissue Infections
      4. Staph haemolyticus
        1. Rare cause of endocarditis, meningitis
  2. Chains
    1. Enterococcus (e.g. Enterococcus faecalis, Enterococcus faecium)
      1. May cause bacteremia in the proper clinical setting (UTI, intra-abdominal infections, infected vascular catheters, and endocarditis)[4]
      2. Strep viridans
        1. In general are low virulence pathogens and likely contaminants (21-50% of positive blood cultures are clinically significant
        2. Risk factors for VGS bacteremia include: neutropenia, oral mucositis, irradiation to the oral cavity, antibiotic prophylaxis with trimethoprim-sulfamethoxazole and fluoroquinolones, intravenous hyperalimentation, high dose chemotherapy
      3. Other Strep Species
        1. ß-hemolytic streptococcus (Group A Streptococcus, Group B Streptococcus, etc)
  3. Pairs
    1. Streptococcus pneumoniae
      1. Asociated with pneumonia, meningitis, peritonitis and other severe infections
      2. Isolation of this organism is always significant and should be treated[5]

Rods (Bacilli)

Organism
Cult Morphology

Listeria monocytogenes

Small

Aero
tumbling
Diphtheroids
Small Anaero
pallisades
Actinomyces
Small Anaero
Branching
Propionibac
Small Anaero
clumps/pleo
Lactobacillus
Variable Both
may chain
Clostridium
Large Anaero
Spores
Bacillus Large Aero Spores

Clinical Identification Chart

Gram-Positive Classification.png

Table Overview

See Also

Source

  1. Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp
  2. Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp
  3. Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp
  4. Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp
  5. Antibiotic Therapy for Positive Blood Cultures. Perez-Jorge EV, et al. Antimicrobe. http://www.antimicrobe.org/new/e38rev2.asp