A 65-year-old man presents to his primary care physician for a routine appointment. He has no concerns. His past medical history is significant for human immunodeficiency virus (HIV) infection, diagnosed 15 years ago. The patient is intermittently compliant with his antiretroviral therapy (ART). His temperature is 99.0°F (37.2°C), blood pressure is 130/84 mmHg, pulse is 92/min, and respirations are 11/min. His most recent lab work showed a cluster of differentiation CD4 count of 150 cells/µL. He received a dose of the 13-valent pneumococcal vaccine and a dose of the 23-valent pneumococcal vaccine 15 years ago, as well as a second dose of the 23-valent pneumococcal vaccine 10 years ago. In addition to encouraging greater compliance with his ART, which of the following is indicated in this patient?
Azithromycin and pneumococcal vaccine
Trimethoprim-sulfamethoxazole and varicella vaccine
Trimethoprim-sulfamethoxazole and zoster vaccine
Trimethoprim-sulfamethoxazole and pneumococcal vaccine
Trimethoprim-sulfamethoxazole and pneumococcal vaccine
This patient with HIV and a CD4 count of 150 cells/μL requires trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis and another dose of the 23-valent pneumococcal vaccine.

All HIV patients with a CD4 count < 200 cells/μL require TMP-SMX as prophylaxis against Pneumocystis jirovecci pneumonia. Patients with CD4 counts < 100 cells/μL also require TMP-SMX as prophylaxis against toxoplasmosis. HIV patients require a dose of the 23-valent pneumococcal vaccine at age 65. Patients should initially receive the 13-valent pneumococcal vaccine, followed by the 23-valent pneumococcal vaccine 8 weeks later, 5 years later, and at age 65. Compliance with ART is also critical in patients with HIV.

Kaplan et al. discuss recommendations for the prevention of opportunistic infections in HIV-infected adults. The authors find that daily prophylaxis with TMP-SMX is an appropriate regimen for the prevention of Pneumocystis pneumonia. The authors recommend dapsone, atovaquone, or pentamidine for patients that cannot receive TMP-SMX.

Incorrect Answers:
Answer A: Azithromycin is used as prophylaxis against Mycobacterium avium complex (MAC) in patients with a CD4 count < 50 cells/μL that has not been started on ART. Since this patient has a CD4 count of 150 cells/μL, azithromycin is not indicated at this time.

Answer B: Azithromycin is used as prophylaxis against Mycobacterium avium complex (MAC) in patients with a CD4 count < 50 cells/μL that has not been started on ART. This patient should not receive the zoster vaccine as it is a live vaccine and is contraindicated in immunocompromised patients.

Answer D: Although this patient does require TMP-SMX as prophylaxis against Pneumocystis pneumonia, he should not receive the varicella vaccine as it is a live vaccine and therefore contraindicated in immunocompromised patients.

Answer E: Although this patient does require TMP-SMX as prophylaxis against Pneumocystis pneumonia, he should not receive the zoster vaccine as it is a live vaccine and therefore contraindicated in immunocompromised patients.

Bullet Summary:
Patients with a CD4 count < 200 cells/μL require prophylaxis with TMP-SMX and all patients with HIV should receive a dose of the 23-valent pneumococcal vaccine at age 65.