Examkin

Question

Difficulty: MediumPharmacologic Interventions

A 58-year-old man is brought to the emergency department by his wife due to fever, severe headache, and confusion that started 12 hours ago. He has a past medical history of alcohol use disorder, type 2 diabetes mellitus, and hypertension. His temperature is 39.2°C (102.6°F), blood pressure is 110/70 mmHg, and heart rate is 115/min. On physical examination, he is lethargic but arousable. There is significant resistance to passive neck flexion. Funduscopic examination shows no papilledema. Lumbar puncture is performed, and cerebrospinal fluid (CSF) analysis reveals a leukocyte count of 2,400/mm³ (90% neutrophils), a glucose level of 30 mg/dL, and a protein level of 150 mg/dL. Gram stain of the CSF is pending.

Which of the following pharmacologic agents should be included in his immediate empiric regimen? (Select all that apply)

  1. AmpicillinAnswer
  2. CeftriaxoneAnswer
  3. VancomycinAnswer
  4. D
    Acyclovir
  5. E
    Gentamicin

Answer

The immediate empiric regimen should include ampicillin, ceftriaxone, and vancomycin.
The patient's clinical presentation and cerebrospinal fluid analysis are consistent with acute bacterial meningitis. In adults aged 2 to 50 years, the most common pathogens are Streptococcus pneumoniae and Neisseria meningitidis, and standard empiric therapy includes vancomycin and a third-generation cephalosporin (e.g., ceftriaxone). However, in patients older than 50 years, or those with altered cellular immunity (such as from alcohol use disorder or diabetes), there is an increased risk of infection with Listeria monocytogenes. Therefore, ampicillin must be added to the empiric regimen. The correct multi-drug regimen includes vancomycin, ceftriaxone, and ampicillin.

Step-by-Step Solution

1
Analyze the patient's clinical presentation and cerebrospinal fluid (CSF) findings.
The combination of fever, headache, nuchal rigidity, altered mental status, and a CSF profile with high neutrophils, low glucose, and high protein indicates acute bacterial meningitis.
Establishing the correct diagnosis dictates the choice of empiric antimicrobial therapy.
2
Identify the patient's demographic and medical risk factors.
The patient is over 50 years old (58 years) and has a history of alcohol use disorder and diabetes mellitus.
Age and comorbidities determine the likely causative organisms and the need for expanded antibiotic coverage.
3
Select the appropriate empiric antibiotic regimen based on the identified risk factors.
Vancomycin and ceftriaxone are selected for baseline coverage, while ampicillin is added specifically to cover Listeria monocytogenes.
Standard empiric therapy for adults includes vancomycin and a third-generation cephalosporin. Ampicillin must be added for patients >50 years or those who are immunocompromised.

Key Concept

Empiric antibiotic therapy for bacterial meningitis in adults >50 years or with immunocompromising conditions (such as alcoholism) requires a combination of vancomycin, a third-generation cephalosporin (e.g., ceftriaxone), and ampicillin.
Rate this question

Topics

Pharmacologic Interventions

More questions from this topic