gram negative bacteria (14)

• What type of bacteria is the Neisseria genus?

  Gram-negative cocci
• How are Neisseria arranged?

  In pairs, known as diplococci
• Which Neisseria species are commensal in the oropharynx?

  1. sicca, N. mucosa, N. lactamica
• What are the true pathogens of the Neisseria genus?

  1. meningitidis and N. gonorrhoeae
• What type of culture medium do Neisseria require?

  Enriched media like chocolate agar
• What is the oxidase reaction of Neisseria?

  Oxidase positive
• What biochemical process do Neisseria perform?

  Carbohydrate oxidation with acid production
• How can meningococcus and gonococcus be differentiated?

  Through biochemical identification methods
• Where is the natural habitat of N. meningitidis?

  Human pharynx (nasopharynx)
• What percentage of the general population are carriers of N. meningitidis?

  5-10%
• How is N. meningitidis transmitted?

  By droplets of oropharyngeal secretions
• What factors influence the development of disease from N. meningitidis?

  Immune status and strain virulence
• What is meningococcemia?

  Hematogenous dissemination causing systemic infection
• What are possible symptoms of meningococcemia?

  Petechiae and purpura
• What can be observed in CSF during meningitis caused by N. meningitidis?

  Intracellular gram-negative diplococci
• How is N. meningitidis classified based on capsular polysaccharide?

  Into serogroups A, B, C, Y, W135
• What are the main serogroups causing meningitis in Spain?

  Serogroups B and C
• What is the peak incidence age for meningitis due to N. meningitidis?

  3 months to 12 months
• When do most cases of meningitis occur seasonally?

  Between December and March
• What is the treatment of choice for N. meningitidis infections?

  Penicillin G if sensitive
• What is the chemoprophylaxis for contacts of N. meningitidis cases?

  Rifampicin for two days
• What type of vaccine is used for serogroups A, C, Y, W135?

  Capsular polysaccharide vaccine
• What is the more efficient vaccine type for N. meningitidis?

  Conjugate vaccine (polysaccharide + protein)
• What is the vaccine against serogroup B called?

  Recombinant protein vaccine
• How does N. meningitidis transmission occur in dental offices?

  Through pharyngeal secretions of patients
• What preventive measures should dentists take against N. meningitidis?

  Mask, hygiene, chemoprophylaxis
• What is the treatment of choice for N. gonorrhoeae infections?

  Cefixime or Ceftriaxone
• What additional treatment is recommended for N. gonorrhoeae to cover Chlamydia?

  Add doxycycline or azithromycin
• What type of bacteria is Pseudomonas aeruginosa?

  Gram-negative rods (bacilli)
• What is a characteristic of Pseudomonas aeruginosa colonies in culture?

  Poorly defined, extended colonies
• What type of metabolism does Pseudomonas aeruginosa have?

  Oxidative metabolism, no sugar fermentation
• What pigments does Pseudomonas aeruginosa produce?

  Pyocyanin and pyoverdine
• What is a common odor associated with Pseudomonas aeruginosa cultures?

  A characteristic fruity odor
• In what situations does Pseudomonas aeruginosa typically cause infections?

  When mucocutaneous barriers are broken
• What are the clinical manifestations of Pseudomonas aeruginosa infections?

  Folliculitis, pneumonia, urinary tract infections
• What is ecthyma gangrenosum?

  A rapidly progressing skin lesion
• What is the treatment for severe Pseudomonas aeruginosa infections?

  Use of effective antibiotics
• What is the Enterobacteriaceae family primarily composed of?

  Gram-negative rods (bacilli)
• What is a key characteristic of Enterobacteriaceae regarding glucose?

  They ferment glucose
• What is the significance of the H, K, and O antigens in Enterobacteriaceae?

  They are used for serotyping