How would you approach treatment of latent TB for patients who cannot tolerate rifamycins or isoniazid due to allergy, intolerance, or drug-drug interactions?  

It is reasonable to talk to a TB expert on this type of situation, if available, as this is an unclear area. In our clinic, we tend to follow the recommendations for contacts of multi-drug resistant TB that are outlined in this document and include recommendations for a later-generation fluoroquinol...

Levofloxacin or moxifloxacin. Duration is 6-9 months. 

A fluoroquinolone, specifically LVF or MXF, can be used, supported by the latest trial done in Vietnam, but I recommend consultation with your county's TB/chest clinic or TB expert.

Depending on the clinical picture, time from primary infection, likelihood of reactivation, and comorbidities, baseline medication. If low risk reactivation, more than 10 years of primary infection, close monitor symptoms, check once a year with primary, a lot of education, and no treatment. If hi...