MIDTERM 03 - Enteric and Other Gram-Negative Bacilli Flashcards
A large, heterogenous group of gram-negative rods whose natural habitat is the intestinal tract of humans and animals; are facultative anaerobes, catalase positive, and oxidase negative
Enterobacteriaceae/Enteric gram-negative bacilli/Coliforms
Test for Enterobacteriaceae that detects the ability to produce indole from tryptophan (IMViC test)
Indole test
Test for Enterobacteriaceae that detects the ability to produce acids (IMViC test)
Methyl red test
Test for Enterobacteriaceae that detects the ability to produce acetoin (IMViC test)
Voges-Proskauer test
Test for Enterobacteriaceae that detects the ability to utilize citrate (IMViC test)
Citrate test
3 media for Enterobacteriaceae that tests the ability to ferment lactose (EMD)
EMB medium, MacConkey medium, Deoxycholate medium
3 enterobacteriaceae that are rapid lactose fermenters (KEE)
Klebsiella, Escherichia, Enterobacter
6 enterobacteriaceae that are late lactose fermenters (ESCAPE)
Edwardsiella, Serratia, Citrobacter, Arizona, Providencia, Erwinia
Most external part of the cell wall LPS and consists of repeating units of polysaccharide (Antigenic structures of Enterobacteriaceae)
O antigens
External to O antigens on some but not all Enterobacteriaceae (Antigenic structures of Enterobacteriaceae)
K antigens
Located on flagella; denatured or removed by heat or alcohol (Antigenic structures of Enterobacteriaceae)
H antigens
Most common cause of UTI; also causes sepsis and meningitis (Examples of Enterobacteriaceae)
Escherichia coli
Causes diarrhea in infants (Diarrheal diseases caused by Escherichia coli)
Enteropathogenic E. coli (EPEC)
Causes traveler’s diarrhea (Diarrheal diseases caused by Escherichia coli)
Enterotoxigenic E. coli (ETEC)
Causes mild non-bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (Diarrheal diseases caused by Escherichia coli)
Shiga toxin-producing E. coli (STEC)
Exhibits symptoms similar to shigellosis (Diarrheal diseases caused by Escherichia coli)
Enteroinvasive E. coli (EIEC)
Causes acute and chronic diarrhea, and traveler’s diarrhea and persistent diarrhea in patients with HIV (Diarrheal diseases caused by Escherichia coli)
Enteroaggressive E. coli (EAEC)
Treatment for Escherichia coli
Fluoroquinolones
An Enterobacteriaceae that has a capsule made of K antigens; causes hospital-acquired pneumonia (Klebsiella species)
Klebsiella pneumoniae/Friedlander’s Bacillus
An Enterobacteriaceae also known as Calymmatobacterium granulomatis; causes granuloma inguinale/donovanosis (Klebsiella species)
Klebsiella granulomatis
An STD that is a chronic genital ulcerative disease that produces pseudobuboes (subcutenous granulomas) (Clinical findings of Klebsiella granulomatis)
Granuloma inguinale/Donovanosis
Treatment for Klebsiella granulomatis
Azithromycin
2 Enterobacteriaceae that causes hospital-acquired infections such as pneumonia, UTI, and wound and device infections (Examples of Enterobacteriaceae)
Enterobacter cloacae, Enterobacter aerogenes
A common opportunistic pathogen in hospitalized patients; causes pneumonia, bacteremia, and endocarditis (Examples of Enterobacteriaceae)
Serratia marcescens
2 Proteus sp. that produces infections in humans only when the bacteria leave the intestinal tract; produces ureases (Examples of Enterobacteriaceae)
Proteus mirabilis, Proteus vulgaris
Enzyme produced by Proteus sp. that hydrolyzes urea with the liberation of ammonia
Urease
Are members of the normal intestinal microbiota; causes UTIs (Examples of Enterobacteriaceae)
Providencia
Causes UTI and sepsis principally among debilitated hospitalized patients; associated with meningitis in infants <2 months of age (Examples of Enterobacteriaceae)
Citrobacter
Its natural habitat is limited to the intestinal tracts of humans and other primates; causes shigellosis (bacillary dysentery) (Examples of Enterobacteriaceae)
Shigella
Shigella causes __________, also known as bacillary dysentery
Shigellosis
Are exotoxins produced by Shigella that is heat-labile, antigenic, enterotoxic, and neurotoxic
Shigella toxins
Treatment/DOC for Shigella (for severe infections)
Ceftriaxone
Are peritrichous bacteria that usually produce H2S and is pathogenic for humans or animals when acquired by the oral route (Examples of Enterobacteriaceae)
Salmonella
2 main species of Salmonella (SE, SB)
Salmonella enterica, Salmonella bongori
Salmonella is cultured using __________
Bismuth sulfite agar
Salmonella that causes typhoid fever
Typhoidal salmonella
Salmonella that do not cause typhoid ever
Non-typhoidal salmonella
Blood culture is positive in first to second weeks of the disease; Stool culture is positive from second week on (Clinical findings of Salmonella)
Enteric fever/Typhoid fever
Blood culture is positive during high fever; Stool culture is infrequently positive (Clinical findings of Salmonella)
Septicemias
Blood culture is negative; Stool culture is positive soon after onset (Clinical findings of Salmonella)
Enterocolitis
Caused by Salmonella serotype Typhi; characterized by fever, malaise, headache, constipation, bradycardia, and myalgia (Clinical findings of Salmonella)
Enteric fever (Typhoid fever)
Associated commonly with the Salmonella serotype choleraesius; characterized by focal lesions in lungs, bones, and meninges and usually has no intestinal manifestations (Clinical findings of Salmonella)
Bacteremia
Most common manifestation of salmonella infection; S. Typhimurium and S. Enteritidis are prominent causes; characterized by nausea, headache, vomiting, and profuse diarrhea (Clinical findings of Salmonella)
Enterocolitis
Treatment for Salmonella
Azithromycin PO
An enterobacteriaceae characterized by bipolar staining with Wright, Giemsa, Wayson, or methylene blue stain; transmitted from rodent to rodent or rodent to humans (Yersinia species)
Yersinia pestis
Main clinical finding for Yersinia pestis; also known as the Black Death of Medieval Europe
Plague
3 types of plague (BSP)
Bubonic, Septicemia, Pneumonic
Characterized by high fever, painful lymphadenopathy, and enlarged tender nodes (buboes) in the neck, groin, or axillae (Types of plague)
Bubonic plague
Characterized by vomiting, diarrhea, DIC, hypotension, altered mental status, renal and cardiac failure, and necrosis of the extremities (Types of plague)
Septicemic plague
Characterized by chest pain, cough, hemoptysis, and severe respiratory distress (Types of plague)
Pneumonic plague
3 treatments for Yersinia pestis (SDG)
Streptomycin, Doxycycline, Gentamicin
An Enterobacteriaceae that causes gastroenteritis or mesenteric lymphadenitis after ingestion of contaminated food or water (Yersinia species)
Yersinia enterocolitica
Most common bacteria in surface waters worldwide; are comma-shaped and halotolerant (Examples of gram-negative bacilli)
Vibrio sp.
Cultured using Thiosulfate-Citrate-Bile-Sucrose (TCBS) agar; is oxidase-positive and caused six pandemics in the past (Vibrio species)
Vibrio cholerae
Characterized by sudden onset of nausea and vomiting, as well as rice water stools (20-30 L/day) (Clinical findings of Vibrio cholerae)
Cholera
Vibrio cholerae is cultured using __________ agar
Thiosulfate-Citrate-Bile-Sucrose agar
Is an electrolyte-rich diarrhea from cholera with mucus, epithelial cells, vibrios, and can lead to dehydration, anuria, shock, acidosis, and death
Rice water stool
Causes acute gastroenteritis after ingestion of contaminated seafood such as raw fish or shellfish (Vibrio species)
Vibrio parahaemolyticus
Causes severe wound infections, bacteremia, and gastroenteritis after oyster consumption (Vibrio species)
Vibrio vulnificus
A comma shaped bacteria that is microaerophilic, oxidase and catalase positive, and is cultured using Skirrow’s medium (Examples of gram-negative bacilli)
Camphylobacter jejuni
Campylobacter jejuni is cultured using __________ medium
Skirrow’s medium
Characterized by acute onset of crampy abdominal pain, profuse diarrhea that may grossly blood, headache, malaise, and fever (Clinical findings of Campylobacter jejuni)
Campylobacteriosis
Characterized by ascending paralytic disease (Clinical findings of Campylobacter jejuni)
Postdiarrheal Guillain-Barre syndrome
A spiral shaped, gram-negative lophotrichous rod that is microaerophilic, oxidase and catalase positive, and produces urease; is cultured using Skirrow’s medium (Examples of gram-negative bacilli)
Helicobacter pylori
Helicobacter pylori produces __________
Urease
Helicobacter pylori is cultured using __________ medium
Skirrow’s medium
Medium used for Campylobacter jejuni and Helicobacter pylori that has reduced O2 and added CO2
Skirrow’s medium
Test used to detect Helicobacter pylori; 13C or 14C labeled urea is ingested by the patient and urease labeled CO2 that can be detected in the patient’s exhaled breath
Urea breath test
Characterized by epigastric pain, vomiting, fever, and bloody stools (Clinical findings of Helicobacter pylori)
Peptic ulcer disease (PUD)
3 treatments for Helicobacter pylori (TPQ)
Triple therapy, PPI for 6 weeks, Quadruple therapy
A gram-negative, motile, obligate aerobic rod which produce water-soluble pigments (Examples of gram-negative bacilli)
Pseudomonas aeruginosa
A pigment produced by Pseudomonas aeruginosa that is fluoroscent green
Pyoverdine
A pigment produced by Pseudomonas aeruginosa that is nonfluoroscent blue
Pyocyanin
A pigment produced by Pseudomonas aeruginosa that is dark red
Pyorubin
A pigment produced by Pseudomonas aeruginosa that is brown-black
Pyomelanin
Used for attachment (Pseudomonas aeruginosa antigenic structures)
Pili, Fimbriae
Responsible for tissue necrosis; major virulence factor for Pseudomonas aeruginosa (Pseudomonas aeruginosa antigenic structures)
Exotoxin A
Occurs due to lumbar puncture (Clinical findings of Pseudomonas aeruginosa)
Meningitis
Occurs due to catheters (Clinical findings of Pseudomonas aeruginosa)
UTI
Occurs due to respirators (Clinical findings of Pseudomonas aeruginosa)
Necrotizing pneumonia
Characterized by hemorrhagic necrosis of the skin surrounded by erythema and has no pus (Clinical findings of Pseudomonas aeruginosa)
Ecthyma gangrenosum
Treatment for Pseudomonas aeruginosa (P+T)
Piperacillin + Tobramycin
Causes melioidosis/Whitemore’s disease (cutaneous, pulmonary, bacteremic, disseminated infection) (Burkholderia species)
Burkholderia pseudomallei
Causes endocarditis, septicemia, wounds, and UTIs (Burkholderia species)
Burkholderia cepacia