100+ Free Cert ID(SA) Phys Practice Questions

Explanation: The 6-month oral BPaLM regimen (Bedaquiline, Pretomanid, Linezolid, and Moxifloxacin) is the WHO and South African NDoH recommended preferred regimen for patients aged ≥ 14 years with rifampicin-resistant/multidrug-resistant TB (RR/MDR-TB) who are fluoroquinolone-susceptible and have not had prior exposure to bedaquiline, pretomanid, or linezolid (> 1 month).

Explanation: In asymptomatic HIV-infected individuals with a positive serum CrAg screening test, a lumbar puncture (LP) must be performed to evaluate for subclinical cryptococcal meningitis before initiating preemptive oral fluconazole. Subclinical meningitis is present in up to 30% of serum CrAg-positive asymptomatic patients and requires full induction antifungal therapy rather than preemptive fluconazole.

Explanation: The single high-dose Liposomal Amphotericin B (10 mg/kg IV on day 1) combined with 14 days of oral Flucytosine (100 mg/kg/day in 4 divided doses) and Fluconazole (1200 mg daily) is the gold-standard induction regimen demonstrated in the landmark AMBITION-cm trial. It offers equivalent efficacy to 7-14 day daily amphotericin regimens with significantly fewer adverse events (anemia, hypokalemia, nephrotoxicity).

Explanation: Antiretroviral therapy (ART) must be delayed for 4 to 6 weeks after starting antifungal therapy in patients with Cryptococcal Meningitis. Early initiation of ART (within 1-2 weeks) in cryptococcal meningitis is associated with significantly increased mortality driven by life-threatening intracranial Immune Reconstitution Inflammatory Syndrome (IRIS) and elevated intracranial pressure.

Explanation: Linezolid causes dose- and duration-dependent mitochondrial toxicity leading to peripheral neuropathy, optic neuritis, and bone marrow suppression (anemia, thrombocytopenia). Management of Linezolid toxicity involves dose reduction to 300 mg daily or temporary interruption until myelosuppression resolves, along with Pyridoxine (Vitamin B6) supplementation (50-100 mg daily).

Explanation: First-line treatment for moderate-to-severe Pneumocystis jirovecii pneumonia (PJP defined by PaO2 < 70 mmHg or A-a gradient ≥ 35 mmHg) is high-dose Trimethoprim-Sulfamethoxazole (15-20 mg/kg/day of TMP component) PLUS adjunctive corticosteroids (Prednisone 40 mg BD for 5 days, then 40 mg daily for 5 days, then 20 mg daily to complete 21 days). Corticosteroids significantly reduce respiratory failure and mortality and must not be withheld in pregnancy when severe hypoxia is present.

Explanation: In HIV-infected patients with severe immunosuppression (CD4 count < 50 cells/µL), ART should be initiated within 2 weeks of starting anti-tuberculosis treatment (except in TB meningitis). Early ART significantly reduces all-cause mortality in severely immunocompromised patients with TB co-infection.

Explanation: Rifampicin markedly induces UGT1A1 and CYP3A4, reducing plasma concentrations of Dolutegravir by approximately 54%. To overcome this induction, Dolutegravir must be increased to 50 mg twice daily (an additional single 50 mg DTG tablet taken 12 hours after the morning TLD combination dose). This dose adjustment must be continued for 2 weeks after stopping Rifampicin.

Explanation: In Tuberculous Meningitis (TBM), ART initiation should be deferred for 4 to 8 weeks after starting anti-TB treatment, regardless of CD4 count. Clinical trials (e.g. TBM-IRIS trials) demonstrated that early ART in TBM does not improve survival and is associated with significantly more severe, life-threatening neurological adverse events and intracranial IRIS.

Explanation: When dolutegravir resistance is confirmed (mutations like G140S/Q148H or R263K), the patient must be switched to a ritonavir-boosted protease inhibitor-based regimen (preferably Darunavir/ritonavir or Lopinavir/ritonavir) combined with two nucleoside reverse transcriptase inhibitors (NRTIs) selected based on NRTI resistance testing (e.g., Zidovudine + Lamivudine or optimized nucleoside backbone).