Podcast
Questions and Answers
A 20-year-old college student presents with a sudden onset of high fever, severe headache, and a stiff neck. A lumbar puncture is performed, revealing a high number of polymorphonuclear leukocytes (PMNs) in the cerebrospinal fluid. Gram staining identifies gram-negative diplococci. Which virulence factor of the suspected organism is most directly responsible for the patient's stiff neck?
A 20-year-old college student presents with a sudden onset of high fever, severe headache, and a stiff neck. A lumbar puncture is performed, revealing a high number of polymorphonuclear leukocytes (PMNs) in the cerebrospinal fluid. Gram staining identifies gram-negative diplococci. Which virulence factor of the suspected organism is most directly responsible for the patient's stiff neck?
- Pili, facilitating attachment to the nasopharyngeal mucosa.
- Endotoxin (lipopolysaccharide) inducing inflammation and increased intracranial pressure. (correct)
- IgA protease, cleaving secretory IgA and aiding in mucosal colonization.
- Polysaccharide capsule, preventing phagocytosis and promoting systemic spread.
A military recruit develops Waterhouse-Friderichsen syndrome. Which combination of virulence factors and clinical manifestations is most characteristic of the pathogenesis of this condition in the context of Neisseria meningitidis infection?
A military recruit develops Waterhouse-Friderichsen syndrome. Which combination of virulence factors and clinical manifestations is most characteristic of the pathogenesis of this condition in the context of Neisseria meningitidis infection?
- Pili-mediated nasopharyngeal colonization leading to localized mucosal damage.
- IgA protease activity causing widespread purpura due to degradation of mucosal antibodies.
- Endotoxin-induced disseminated intravascular coagulation, thrombocytopenia, and adrenal insufficiency. (correct)
- Capsular polysaccharide inhibiting complement activation, resulting in chronic inflammation.
In a population with a known outbreak of Neisseria meningitidis, a rapid diagnostic test is needed. Which combination of laboratory findings would most specifically identify Neisseria meningitidis and differentiate it from Neisseria gonorrhoeae?
In a population with a known outbreak of Neisseria meningitidis, a rapid diagnostic test is needed. Which combination of laboratory findings would most specifically identify Neisseria meningitidis and differentiate it from Neisseria gonorrhoeae?
- Gram-negative diplococci that are oxidase-positive and ferment glucose only.
- Gram-negative diplococci that are oxidase-positive and ferment both maltose and glucose. (correct)
- Gram-negative diplococci that are oxidase-negative and ferment both maltose and glucose.
- Gram-negative diplococci that are oxidase-positive and ferment maltose only.
A researcher is studying the mechanism by which Neisseria meningitidis evades the host's immune response. Which virulence factor directly interferes with complement-mediated killing?
A researcher is studying the mechanism by which Neisseria meningitidis evades the host's immune response. Which virulence factor directly interferes with complement-mediated killing?
During an outbreak of Neisseria meningitidis in a college dormitory, prophylactic treatment is administered to close contacts of infected individuals. Which of the following is the most appropriate rationale for using rifampin or ciprofloxacin as prophylactic agents?
During an outbreak of Neisseria meningitidis in a college dormitory, prophylactic treatment is administered to close contacts of infected individuals. Which of the following is the most appropriate rationale for using rifampin or ciprofloxacin as prophylactic agents?
An unvaccinated adolescent contracts Neisseria meningitidis meningitis. Despite prompt antibiotic treatment, the patient develops disseminated intravascular coagulation (DIC) and adrenal hemorrhage, leading to Waterhouse-Friderichsen syndrome. Which of the following pathophysiological processes is the primary driver of these complications?
An unvaccinated adolescent contracts Neisseria meningitidis meningitis. Despite prompt antibiotic treatment, the patient develops disseminated intravascular coagulation (DIC) and adrenal hemorrhage, leading to Waterhouse-Friderichsen syndrome. Which of the following pathophysiological processes is the primary driver of these complications?
A researcher aims to develop a novel vaccine against Neisseria meningitidis. Which of the following strategies would likely be most effective in providing broad protection against multiple serogroups of this bacterium?
A researcher aims to develop a novel vaccine against Neisseria meningitidis. Which of the following strategies would likely be most effective in providing broad protection against multiple serogroups of this bacterium?
A patient is suspected of having Neisseria meningitidis meningitis. A cerebrospinal fluid (CSF) sample is collected and sent to the laboratory for analysis. Which finding would provide the most rapid and specific confirmation of Neisseria meningitidis as the causative agent?
A patient is suspected of having Neisseria meningitidis meningitis. A cerebrospinal fluid (CSF) sample is collected and sent to the laboratory for analysis. Which finding would provide the most rapid and specific confirmation of Neisseria meningitidis as the causative agent?
A physician is evaluating a patient presenting with symptoms suggestive of meningitis. After performing a lumbar puncture, the CSF analysis reveals the presence of gram-negative diplococci. Given the patient's age and clinical presentation, Neisseria meningitidis is suspected. Besides antibiotics, what adjunctive therapy should be promptly considered in managing this patient to reduce the risk of adverse outcomes?
A physician is evaluating a patient presenting with symptoms suggestive of meningitis. After performing a lumbar puncture, the CSF analysis reveals the presence of gram-negative diplococci. Given the patient's age and clinical presentation, Neisseria meningitidis is suspected. Besides antibiotics, what adjunctive therapy should be promptly considered in managing this patient to reduce the risk of adverse outcomes?
A microbiologist is analyzing a clinical isolate suspected to be Neisseria meningitidis. Given that both N. meningitidis and N. gonorrhoeae are oxidase-positive and grow on chocolate agar, what key metabolic difference can be used to definitively differentiate between these two species in the laboratory?
A microbiologist is analyzing a clinical isolate suspected to be Neisseria meningitidis. Given that both N. meningitidis and N. gonorrhoeae are oxidase-positive and grow on chocolate agar, what key metabolic difference can be used to definitively differentiate between these two species in the laboratory?
Flashcards
Neisseria meningitidis
Neisseria meningitidis
Gram-negative bacteria that frequently causes meningitis, especially in teenagers and young adults. Contains pili and is encapsulated with a polysaccharide capsule.
Meningococcemia
Meningococcemia
A condition caused by Neisseria meningitidis, characterized by high fever, shock, widespread purpura, disseminated intravascular coagulation, thrombocytopenia, and adrenal insufficiency.
Meningitis (caused by N. meningitidis)
Meningitis (caused by N. meningitidis)
Inflammation of the meninges characterized by fever, headache, stiff neck, and an increased level of PMNs in spinal fluid.
Immunoglobulin A protease
Immunoglobulin A protease
Signup and view all the flashcards
Factor H binding protein
Factor H binding protein
Signup and view all the flashcards
Treatment for N. meningitidis
Treatment for N. meningitidis
Signup and view all the flashcards
Conjugate meningococcal vaccine
Conjugate meningococcal vaccine
Signup and view all the flashcards
Study Notes
- Neisseria meningitidis frequently causes meningitis, especially in teenagers and young adults
- This bacteria is gram-negative and contains pili
- Encapsulation with a polysaccharide capsule contributes to its virulence
- It grows on chocolate agar and is oxidase-positive
- It ferments both maltose, unlike N. gonorrhoeae, and glucose
- Transmission occurs via airborne droplets, colonizing nasopharynx membranes
- The bacteria can then spread through the bloodstream
- Carriers are often asymptomatic
- Close living quarters, such as military barracks, can have carrier rates as high as 35%, leading to outbreaks
- Endotoxin is a key virulence factor, causing fever and shock
- Meningococcemia (Waterhouse-Friderichsen syndrome) is characterized by high fever, shock, widespread purpura, disseminated intravascular coagulation, thrombocytopenia, and adrenal insufficiency
- Meningitis symptoms include fever, headache, stiff neck, and increased PMNs in spinal fluid
- Immunoglobulin A protease cleaves secretory IgA
- Factor H binding protein defends against complement-mediated killing
Diagnosis & Treatment
- Diagnosis involves Gram stain of CSF, chocolate agar culture, oxidase testing, maltose/glucose fermentation tests, and latex agglutination
- Penicillin G or ceftriaxone are effective treatments
- A conjugate meningococcal vaccine is available for adolescents and adults aged 11-55
- Prophylaxis for close contacts includes rifampin, oral ciprofloxacin, or intramuscular ceftriaxone
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
