Shigella sonnei

 

1. What is Shigella sonnei?

























Shigella sonnei is a species of Shigella, a Gram-negative, rod-shaped, non-motile, and non-spore-forming bacterium. It is one of the primary causes of shigellosis, a diarrheal disease12.

2. Transmission of Shigella sonnei

Shigella sonnei is primarily transmitted through the fecal-oral route. This can occur via contaminated food or water, direct person-to-person contact, or contact with contaminated surfaces. It can also spread during sexual activity involving exposure to feces2.

3. Epidemiology of Shigella sonnei

Shigella sonnei is responsible for the majority of shigellosis cases in industrialized countries. It is particularly prevalent in areas with poor sanitation and hygiene. Children under five, travelers to endemic areas, and men who have sex with men are at higher risk23.

4. Pathology, Disease, and Infection Caused by Shigella sonnei

Shigella sonnei causes shigellosis, characterized by symptoms such as diarrhea (which can be bloody), fever, stomach cramps, and tenesmus (a feeling of needing to pass stools even when the bowels are empty). Severe cases can lead to complications like dehydration, hemolytic uremic syndrome (HUS), and reactive arthritis12.

5. Laboratory Tests for Shigella sonnei

6. List of Specimen Types for Shigella sonnei

7. List of Specimen Collection Sites

8. Colony Morphology of Shigella sonnei

  • Edge: Entire
  • Elevation: Low convex
  • Surface: Smooth
  • Size: Small to medium
  • Form: Circular
  • Opacity: Opaque
  • Colour: Pale or colorless
  • Consistency: Moist
  • Effect on the Media: No significant effect
  • Pigment: None13

If you need more detailed information or have any other questions, feel free to ask!

Learn more

1 en.wikipedia.org

2cdc.gov

3microbewiki.kenyon.edu

4medlineplus.gov



















Learn more

1cdc.gov2uptodate.com3cdc.gov4bestpractice.bmj.com5gettyimages.com


10. Antimicrobial Susceptibility Testing (AST) for Shigella sonnei

Antimicrobial susceptibility testing (AST) is crucial for determining the most effective antibiotics to treat infections caused by Shigella sonnei, especially given the increasing prevalence of antibiotic-resistant strains.

Commonly Tested Antibiotics

  • Azithromycin
  • Ciprofloxacin (a fluoroquinolone)
  • Ceftriaxone (a third-generation cephalosporin)
  • Trimethoprim-sulfamethoxazole (TMP-SMX)
  • Ampicillin12

Resistance Patterns

Testing Methods

  1. Culture and Sensitivity Testing: If a culture is positive for Shigella, AST is performed to determine the susceptibility of the bacteria to various antibiotics2.
  2. Culture-Independent Diagnostic Tests (CIDTs): If Shigella is detected via CIDTs, a reflex culture should be requested to perform AST2.

Importance of AST

If you have any more questions or need further details, feel free to ask!

Learn more

1 publichealthontario.ca

2 emergency.cdc.gov

3 annalsmicrobiology.biomedcentral.com






Comments

Post a Comment

Popular posts from this blog

  For bacteriology testing aimed at identifying and conducting Antimicrobial Susceptibility Testing (AST) for GLASS (Global Antimicrobial Resistance Surveillance System) priority pathogens , various reagents and supplies are typically required. Here's a list of essential reagents for such testing: 1. Culture Media: Nutrient Agar : For general cultivation of bacteria. Blood Agar : For growing fastidious organisms and detecting hemolytic activity. MacConkey Agar : For selective isolation of Gram-negative bacteria, particularly Enterobacteriaceae. Mannitol Salt Agar : For the selective isolation of Staphylococcus aureus . Chocolate Agar : Enriched medium for fastidious organisms like Haemophilus and Neisseria species. Cetrimide Agar : For selective isolation of Pseudomonas aeruginosa . XLD Agar (Xylose Lysine Deoxycholate) : For selective isolation of Salmonella and Shigella . 2. Gram Staining Reagents: ...
Read more

Citrobacter freundii

Image
1. What is Citrobacter freundii? Citrobacter freundii  is a species of facultative anaerobic Gram-negative bacteria belonging to the family Enterobacteriaceae. It is rod-shaped and typically measures 1-5 μm in length.  This bacterium is commonly found in soil, water, sewage, food, and the intestinal tracts of animals and humans 1 2 . 2. Transmission of Citrobacter freundii Citrobacter freundii  can be transmitted through: Direct contact : With contaminated surfaces or materials. Ingestion : Of contaminated food or water. Nosocomial transmission : In healthcare settings, particularly affecting immunocompromised patients 2 . 3. Epidemiology of Citrobacter freundii Citrobacter freundii  is widely distributed in the environment and is a common component of the gut flora.  It is considered an opportunistic pathogen, primarily causing infections in immunocompromised individuals, the elderly, and those with prolonged hospital stay...
Read more

Spearman's Rank Correlation Coefficient (ρ)

Image
 Spearman's Rank Correlation Coefficient (ρ) Definition: Spearmans' rank correlation coefficient is a non-parametric measure of the correlation between two variables that examines the relationship between their rankings, rather than their actual values. Formula: $$ρ = \frac{\sum{i=1}^{n} (ri - si)^2}{\sum{i=1}^{n} (ri^2 + si^2 - 1)}$$ where:  n is the number of paired observations  ri is the rank of the i-th observation in the first variable  si is the rank of the i-th observation in the second variable Interpretation:  -1 ≤ ρ ≤ 1  ρ = 1: Perfect positive correlation (rankings of both variables are exactly the same)  ρ = -1: Perfect negative correlation (rankings of the variables are exactly opposite)  ρ = 0: No correlation (no relationship between the rankings) Assumptions:  The data should be ordinal, i.e., their values represent ranks or positions.  The relationship between the variables should be monotonic, i.e., as one variable incr...
Read more