How do I know if I have a bacterial sinus infection?

I am asked this question several times each work day. It's a good question. The answer is not so easy though. I make the diagnosis of a bacterial sinus infection based on the history, physical examination, and diagnostic tests. 99.99% of the time this diagnostic test is either a nasal smear or a nasal culture. 0.01% of the time this test may be a nasal endoscopy or CT scan of the sinuses. The historical facts may include: pain in the sinuses, nasal congestion, increase in nasal mucus. The physical examination may show: sinus tenderness, nasal congestion, irritation of the nasal mucosa, nasal mucus that is clear or yellow or greenish, postnasal drip, swollen tonsils or swollen lymph nodes in the neck. A nasal smear is an examination of the nasal mucus, which has been stained to see the cells more easily, with high power magnification using microscope. If I see bacteria, end of the chapter "What's is the diagnosis" and onto the next chapter "What's the optimal treatment in this case?" A nasal culture is a test where the nasal mucus is spread on a petri dish and then any bacteria that grow are identified for species as well as sensitivity to antibiotics. This is particularly helpful in persistent or recurrent cases of bacterial sinusitis. This may guide us to continue the same antibiotic or to change the antibiotic if a drug-resistant species of bacteria grows.


Time for a tangent. It's my story. I got a severe sinus infection when I was thirty years old. Now prior to this, I recommended nasal sinus rinses and never had what I thought of as a bacterial sinus infection. I have never taken an antibiotic for sinus infection to the best of my recollection. I had very thick opaque green mucus with blood mixed in, coming all day and night from my nose. I was gagging and coughing constantly. I couldn't speak without at least clearing my throat every minute. I tried decongestant medications without success. I checked a nasal smear on myself. I saw much bacteria and many white blood cells. I thought I would get over it. After two weeks, I started taking an antibiotic and doing nasal sinus rinses four times per day. Finally, I was practicing what I preached for the past eight years. It certainly took me some time to get used to doing the nasal rinses. My technique has improved so that I can get as much of the solution as possible up into the superior part of my nose and sinuses. How? By bending way over, as I demonstrated in a prior entry (see my photos), to technically have the best chance of rinsing out the entire nasal cavity and the sinuses. This rinses out the mucus from the nasal and sinus cavities much more effectively. I got much better in two to three days and completely better in one week. As I wrote earlier, I have not stopped doing nasal rinses at least four times per day since then. I did them when I was in China visiting relatives, when I have been camping, and when I was on a boat for scuba diving off the Florida Keys with my son's Boy Scout Troop. There's no reason to stop, in my opinion. I have felt a sinus infection coming on many times and then increased my rinsing to at least eight times per day. I am walking the walk at least four times every day. I have yet to ever need to take an antibiotic for a sinus infection again.


About two weeks ago, for the 2,013,579th time since I entered practice, a patient asked me if green mucus meant a bacterial infection. Not necessarily. Patients can have totally clear mucus, which under the microscope is loaded with bacteria. When I got what I thought was a cold twelve days ago, I decided to experiment on myself. I have done a nasal smear on myself everyday for the past 12 days. I also wanted to see if nasal sinus rinsing gave me relief if I did develop bacterial sinus infection. I saw many inflammatory white blood cells, thick and stringy mucus, dark greenish in color for seven or eight days, but no bacteria. I think rinsing helped to prevent an overgrowth of bacteria from occurring. This was a fairly bad episode. I have been tired. My right upper teeth were throbbing whenever I walked, or went up the stairs, or was in bed. Three days ago, I had a dental checkup. The dentist did a routine panoramic x-ray of my teeth - a special single x-ray of all of the teeth on one film. I asked him what he saw, though I was looking intently at the film also. He saw a clear left maxillary sinus and 5-6 mm of mucosal thickening in the right maxillary sinus, to him indicative of sinus inflammation. I agreed and told him about my symptoms and my little experiment. Turns out, he shared that he also uses nasal sinus rinses for sinus infections.

From where does the green color come then if not from bacteria? White blood cells called neutrophils are produced in large numbers in response to infections. They help give mucus its cloudy character. The greenish color comes from an enzyme within neutrophils called myeloperoxidase. [I KNEW that, but read this reference for citations.] Green mucus does not equal bacteria.

I routinely recommend frequent nasal sinus rinsing. It's not that bad once you get used it. You have to blow your nose anyways. And what do you get? A sore nose, possibly a bloody nose from wiping and blowing hard repeatedly, stopped up ears, and lots of used up tissues. Why not get as much of the mucus out, with less effort, reduce the hated sticky and salty, post-nasal drip, all in the same amount time? Nasal rinses loosen up and dilute the mucus and then removing it is all the quicker and easier. There are no studies to determine how to best rinse the nasal cavity. You can pour saline solution in using a Netipot, or you can manually pump saline solution in using the squeeze bottles (discussed in the prior entry), or you can spray saline solution from a pressurized can, or you can mechanically pump saline solution using a Waterpik with a special adaptor attached for the nose(called a GroSsan Sinus irrigator tip). IT DOES NOT MATTER HOW YOU GET THE SALINE SOLUTION INTO YOUR NASAL CAVITY. WHAT MATTERS IS HOW OFTEN YOU RINSE YOUR NASAL CAVITY EVERY DAY AND HOW MUCH SOLUTION YOU USE WHEN YOU DO IT! Personally, I use a squeeze bottle because it is portable, quick, and I like having the solution run briskly, not trickle slowly, through my nose to help rinse out my gooey nasal mucus.

To quote Falstaff (in Henry IV, Act V, Scene i) "and so ends my catechism" on nasal sinus rinsing. If you have questions, ask your doctor.