TB NTM Anki Case Vignette - Drew

A 55-year-old man born in a high-TB-prevalence country has recent close contact with pulmonary TB. He has no cough, fever, or weight loss; chest X-ray is normal; TST induration is 10 mm. What is the most likely diagnosis and treatment goal?

TB infection (latent TB infection), not active disease. Evaluate for preventive treatment; the goal is to prevent progression to active TB disease.

A 40-year-old patient with prior BCG vaccination needs TB screening and can complete a blood draw today. Which screening test is preferred and why?

Use an IGRA. It is preferred in BCG-vaccinated persons because prior BCG does not cause the same false-positive concern seen with TST.

A patient had a positive IGRA 3 years ago, completed TB infection treatment, and asks for a repeat IGRA to prove cure. What should you recommend?

Do not repeat the IGRA for treatment response. Once TST or IGRA is positive, repeated testing has no clinical utility after treatment, and these tests cannot determine treatment response.

A 32-year-old asymptomatic patient has confirmed TB infection, no rifamycin contraindication, and strongly prefers the shortest convenient regimen. Which regimen from the lecture is a preferred option?

3HP: isoniazid plus rifapentine once weekly for 3 months (12 doses), given by DOT or self-administered when appropriate.

A pregnant patient with TB infection is being considered for 3HP. What feature of the regimen makes it inappropriate according to the lecture?

Rifapentine is not approved for pregnancy in the lecture's 3HP table; select another appropriate regimen after assessing risks, interactions, and timing.

A patient needs TB infection treatment but cannot use a rifamycin because of a major drug interaction. Which alternatives should be considered?

Isoniazid monotherapy for 6 months (6H) or 9 months (9H); these are alternative regimens when rifamycins cannot be used.

A 3-year-old child had close TB exposure 4 weeks ago. The TST is negative, but the child is at high risk for rapid progression. What strategy is appropriate?

Window prophylaxis: treat despite the initial negative test because immune conversion can take 2 to 8 weeks. The lecture uses isoniazid for 9 months in high-risk patients such as children under 5.

A patient taking TB infection therapy returns for a routine monthly visit and feels well. What three areas should be assessed at least monthly?

Medication adherence, signs/symptoms of TB disease, and signs/symptoms of adverse drug effects.

A patient taking isoniazid reports new tingling in both feet. What toxicity should you suspect and what preventive/treatment measure is emphasized?

Isoniazid-associated peripheral neuropathy. Assess neuropathy and use pyridoxine, particularly in high-risk patients; the lecture lists 25 to 50 mg/day.

A patient taking isoniazid plus a rifamycin reports fatigue, nausea, and dark urine. What toxicity is most concerning and what should be evaluated?

Drug-induced hepatitis/hepatotoxicity. Promptly assess liver function and the TB regimen rather than waiting until the next routine visit.

A 35-year-old has 3 weeks of cough, hemoptysis, fever, night sweats, weight loss, an upper-lobe cavity, and an AFB-positive sputum smear. Should treatment wait for culture confirmation?

No. With high clinical suspicion and an AFB-positive smear, initiate active-TB treatment while obtaining/awaiting culture and susceptibility results; delaying therapy increases transmission.

A nonpregnant 35-year-old weighing 70 kg has drug-susceptible pulmonary TB without excluded extrapulmonary sites. Which regimen is preferred in the lecture?

The 4-month HPMZ regimen: 8 weeks of high-dose rifapentine + isoniazid + pyrazinamide + moxifloxacin daily, then 9 weeks of rifapentine + isoniazid + moxifloxacin daily.

A patient completes the first 8 weeks of HPMZ, has drug-susceptible pulmonary TB, and cultures are now negative. What is the continuation regimen?

Rifapentine + isoniazid + moxifloxacin daily for 9 additional weeks.

A patient receiving standard RIPE therapy has cavitary pulmonary TB and the sputum culture remains positive at 8 weeks. How does this affect duration?

Extend the continuation phase so total treatment is 9 months (the lecture describes a 7-month continuation phase in this setting).

A patient taking ethambutol reports blurred vision and difficulty distinguishing colors. What toxicity is suspected and what monitoring is appropriate?

Ethambutol optic toxicity/optic neuritis. Assess visual acuity (e.g., Snellen) and color vision (e.g., Ishihara).

A patient taking moxifloxacin as part of HPMZ also has risk factors for QT prolongation. What safety test is appropriate?

Obtain/monitor an ECG for QTc prolongation when risk factors are present.

A patient has rifampin-resistant TB. Susceptibility testing shows the isolate is fluoroquinolone susceptible. Which 26-week all-oral regimen is identified in the lecture?

BPaLM: bedaquiline + pretomanid + linezolid + moxifloxacin for 26 weeks.

A patient has rifampin-resistant TB with fluoroquinolone resistance. Which 26-week regimen is identified in the lecture?

BPaL: bedaquiline + pretomanid + linezolid for 26 weeks.

A 68-year-old with bronchiectasis has worsening fatigue, weight loss, increased sputum, nodular/bronchiectatic CT findings, and MAC isolated from sputum twice. What regimen is appropriate?

Treat confirmed, clinically significant MAC pulmonary disease with a macrolide (azithromycin or clarithromycin) + ethambutol + a rifamycin, typically rifampin.

A patient with MAC pulmonary disease starts multidrug therapy. How should response and duration be assessed?

Use longitudinal clinical symptoms, radiographic change, adverse effects, and mycobacterial culture results. NTM therapy is prolonged; the lecture emphasizes combination therapy for at least 12 months after sputum culture conversion.