Hey there salncrackers,
There's the american health care system for ya eh? I feel bad that not everyone is covered. There are lots of holes in the Canadian system, that's for sure, but at least everyone is covered. Hopefully that changes for you guys under the Obama administration.
Anyway, so yeah, nasal infections are often secondary to Staphylococcus aureus which is either methicillin sensitive (MSSA) or resistant (MRSA). If you have a second, read the "sticky" at the top of this area of the board where i wrote a little blurb on MRSA.
Are there any visible boils on/in your nose? Why did you go to the doctor/NP in the first place? Do you have a fever? Have you had problems with boils before? Are you having nasal discharge? Blood? Pus? Do you have a headache? Any change in your vision or seeing double?
I don't understand how the NP diagnosed a "sinus infection" by just examining you. If you truly had a Staphylococcal sinus infection, you would be much sicker and not posting here
That said, you probably DO have a nasal cellulitis, and one of the treatments for this is Septra (Bactrim in the States). There is enough MRSA in the States that for soft tissue infections, it's good to simply treat them all as MRSA. In Canada, we still have a lot of MSSA, so you can start treatment with a semi-synthetic penicillin or 1st generation cephalosporin.
If you get repeated nasal infections or skin boils, or this doesn't totally get better:
#1. You should be seen by the doctor not the NP
#2. A swab should definitely be taken.
Depending on the patient's preferences, we usually would suggest decolonization (i.e. chlorhexidine baths, oral anbiotics and nasal ointment) if the person is having repeated MRSA/MSSA infections. After the first infection, most people wouldn't do anything because it often goes away on its own.
If you develop a worsening fever, red eyes and/or double vision, go to the ER immediately. Those are symptoms of a severe sinus infection. Otherwise, I'm not sure why you were given that diagnosis.