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Shigella - Gram stain.
Morphology Good bar
Relation to oxygen facultatively anaerobic
Cultivation blood agar , lactose agar
Antigens 38 antigenic structures
Virulence factors Shiga toxin
Source human - an exclusively human pathogen
Transmission alimentary, fecal-oral route
Incubation time 1-4 days
Disease bacterial dysentery, shigellosis
Diagnostics stool cultivation
Therapy diet, antiseptics, etc. ( cotrimoxazole , azithromycin , ciprofloxacin )
MeSH ID D012760

Shigels are divided into 4 subgroups:

  • A with the subspecies S. dysenteriae ,
  • B - S. flexneri ,
  • C - S. boydii ,
  • D - S. sonnei .

They are the least chemically active of all enterobacteria.

Antigenic structure[edit | edit source]

The above 4 species can be differentiated into 38 different antigenic structures (except S. sonnei , which occurs in only one serotype).

Pathogenicity[edit | edit source]

    • Entrance gate: oral cavity.
    • Reproduction in the small intestine.
    • Transition to the colon and the epithelium that destroys it. Shigel penetration into epithelial cells is encoded by a large plasmid, which has also been found in enteroinvasive E. coli . The plasmid encodes the structure of outer membrane proteins that allow the microorganism to bind to the microvilli and initiate microbe-induced phagocytosis .
    • The virulent type of S. dysenteriae forms a Shiga toxin that causes paralysis in small animals. It interferes with the proteosynthesis of sensitive cells and kills them.

Epidemiology[edit | edit source]

    • The most affected are children from 6 months to 10 years .
    • Adults get sick most often as a result of contact with sick children.
    • Epidemics are affecting facilities where hygiene standards are difficult to maintain.
    • The rapid spread is caused by the high infectivity of the germs and the fact that less than 200 bacteria can cause the disease.
    • The current pandemic strain - resistant to sulfonamides , tetracyclines , chloramphenicol , ampicillin and trimethoprim - has very few treatment options.

Clinical picture[edit | edit source]

    • The incubation period is 1-4 days.

Shigella dysenteriae in the stool of a patient with shigeliosis

    • Clinical signs of bacillary dysentery: fever, painful urge, high frequency of stools with mucus and blood. The infection lasts 2-3 days.

Laboratory diagnostics[edit | edit source]

    • Cultivation of stool samples on Endo agar or DC agar . It is also possible to use chromogenic agars or XLD (xylose-lysine deoxycholate) agar , on which we detect lactose fermentation and H 2 S formation.
    • Serotyping of suspect strains.

Therapy[edit | edit source]

    • In the uncomplicated course, symptomatic treatment (adherence to diet and intestinal antiseptics).
    • The use of ATB is unavoidable only for young children and the elderly. ATB prevents the spread to deeper layers of the mucosa.

Prevention[edit | edit source]

    • Hygiene and hand washing.

Links[edit | edit source]

related articles[edit | edit source]

References[edit | edit source]

  • HORACEK, Jiri. Basics of medical microbiology. 1st edition. Prague: Karolinum Publishing House, 2000. vol. 1.  ISBN 80-246-0006-4. .
    • GOERING, Richard V and Hazel M DOCKRELL. Mims' medical microbiology. 5th edition. Prague: Triton, 2016. 568 pp.  ISBN 978-80-7387-928-0 .

Reference[edit | edit source]

  1. BENEŠ, Jiří. Infectious medicine. 1st edition edition. Galén, 2009. 651 pp. 234–235. ISBN 978-80-7262-644-1 .
  2. Jump up to:a b c GOERING, Richard V and Hazel M DOCKRELL. Mims' medical microbiology. 5th edition. Prague: Triton, 2016. 568 pp. 283.  ISBN 978-80-7387-928-0 .
G +
Micrococcus Micrococcus luteus
Rhodococcus Rhodococcus equi
facultatively anaerobic
Enterococcus Enterococcus duransEnterococcus faecalisEnterococcus faecium
Streptococcus Streptococcus agalactiaeStreptococcus mutansStreptococcus pneumoniaeStreptococcus pyogenesStreptococcus suisOral streptococci
Staphylococcus Staphylococcus aureusStaphylococcus epidermidisStaphylococcus intermediusStaphylococcus saprophyticus
Peptococcus Peptococcus niger
Peptostreptococcus Peptostreptococcus anaerobiusPeptostreptococcus prevotiiPeptostreptococcus vaginalis
aerobic + facultative anaerobic
Arcanobacter Arcanobacterium haemolyticum
Bacillus Bacillus anthracisBacillus cereus
Corynebacterium Corynebacterium diphtheriaeCorynebacterium jeikeiumCorynebacterium ulceransCorynebacterium urealyticum
Erysipelothrix Erysipelothrix rhusiopathiae
Listeria Listeria monocytogenes
Nocardia Nocardia asteroidesNocardia brasiliensis
Rhodococcus Rhodococcus equi
Actinomyces Actinomyces israeli • Actinomyces naeslundi
Bifidobacterium Bifidobacterium dentium
Clostridium Clostridium botulinumClostridium difficileClostridium novyiClostridium tetaniClostridium perfringensClostridium septicumClostridium ulcerans
Lactobacillus Lactobacillus acidophilus
Propionibacterium Propionibacterium acnesPropionibacterium propionicus
Acinetobacter Acinetobacter calcoaceticus
Moraxella Moraxella catarrhalisMoraxella lacunata
Neisseria Neisseria gonorrhoeaeNeisseria meningitidisNon-pathogenic species of Neisseria
Veillonella Veillonella alcalescensVeillonella parvula
Rickettsia Rickettsia prowazekiiRickettsia rickettsiiRickettsia typhi
Alcaligentes Alkaligentes feacalis
Bartonella Bartonella bacilliformisBartonella henselaeBartonella quintana
Bordetella Bordetella bronchisepticaBordetella parapertussisBordetella pertussis
Brucella Brucella abortusBrucella canisBrucella melitensisBrucella suis
Burkholderia Burkholderia cepaciaBurkholderia malleiBurkholderia pseudomallei
Francisella Francisella tularensis
Legionella Legionella pneumophila
Kingella Kingella denitrificansKingella kingaeKingella oralis
Pseudomonas Pseudomonas aeruginosaPseudomonas fluorescens
Stenotrophomonas Stenotrophomonas maltophilia
facultatively anaerobic
Actinobacillus Actinobacillus equliActinobacillus lignieresii
Aeromonas Aermonas caviaeAeromonas hydrophilaAeromonas sobria
Afipia Afipia felis
Citrobacter Citrobacter freundiCitrobacter koseri
Eikenella Eikenella corrodens
Enterobacter Enterobacter aerogenesEnterobacter cloacae
Escherichia Escherichia coli
Haemophilus Haemophilus ducreyiHaemophilus haemolyticusHaemophilus influenzaeHaemophilus parainfluenzae
Klebsiella Klebsiella granulomatisKlebsiella oxytocaKlebsiella pneumoniae
Pasteurella Pasteurella haemolyticaPasteurella multocidaPasteurella ureae
Plesiomonas Plesiomonas shigelloides
Proteus Proteus mirabilisProteus vulgaris
Salmonella Salmonella EnteritidisSalmonella TyphiSalmonella Paratyphi
Serratia Serratia marcescens
Shigella Shigella boydiiShigella dysenteriaeShigella flexneriShigella sonnei
Vibrio Vibrio choleraeVibrio parahemolyticus
Yersinia Yersinia enterocoliticaYersinia pestisYersinia pseudotuberculosis
Campylobacter Campylobacter coliCampylobacter fetusCampylobacter jejuni
Helicobacter Helicobacter pylori
Bacteroides Bacteroides fragilisBacteroides vulgatus
Fusobacterium Fusobacterium necrophorumFusobacterium nucleatumFusobacterium stabile
Leptotricha Leptotricha buccalis
Mobiluncus Mobiluncus curtisiiMobiluncus mulieris
Prevotella Prevotella melaninogenica
Porphyromonas Porphyromonas gingivalis
acid resistant
Mycobacterium Atypical mycobacteriaMycobacterium tuberculosisMycobacterium leprae
non-stainable G +/-
strictly aerobic
Leptospira Leptospira biflexaLeptospira interrogansLeptospira parva
Borrelia Borrelia burgdorferiBorrelia hermsiBorrelia recurrentisBorrelia vincenti
strictly anaerobic
Treponema Non-pathogenic treponemsTreponema carateumTreponema pallidumTreponema phagedenisTreponema pertenue
Portal: Microbiology