The smear is the preliminary, done quickly in the lab, and often there is not enough time for the bacteria to show up. The culture is done under controlled conditions, and at 12 days they still cannot quite tell the extent of the infection, your doc will be contacting you with next steps. Whether you are treated with antibiotics depends on the severity of the infection, the condition of your lungs, your symptoms and whether they think you can tolerate the regimen. With M Abscessus an infectious disease doc may also be brought in.

Can you contact your doctor on Monday?