BOSTON When diagnosing sinusitis a bacterial infection it is important to distinguish sinusitis from a viral upper respiratory infection (URI) or an allergic reaction, explained Ellen Wald, MD, because the latter will not be helped by antimicrobial therapy.
"The problem is created because the membranes that line the nose are continuous with the membranes that line the sinus cavities. In some sense, every time you have a cold, you have not only some element of rhinitis, but inflammation of the sinuses as well," she explained at the American Academy of Pediatrics annual meeting held here. "But this is not what we mean when we think of clinically significant infection."
Most children and adults recover from URIs without needing antimicrobials. "The key question is when if ever, during a URI are antimicrobials required to either shorten the course of a clinical illness or to prevent intracranial or intraorbital complications," said Wald, professor of pediatrics at the Pittsburgh University School of Medicine.
"I think that the notion in the lay community, and I think it is shared by some practitioners, that if ever in the course of a respiratory infection, nasal discharge becomes purulent that that is an indication of a bacterial disease, and that calls for antimicrobial therapy," she said. "But studies of the common cold teach us, that the quality of nasal discharge undergoes a variety of changes during the course of even an uncomplicated viral upper respiratory infection."
She explained that a common cold begins with a clear nasal discharge; after a few days, the discharge becomes mucoid, then purulent thick colored and opaque. After a few days the process reverses: the purulent discharge becomes mucoid, the mucoid becomes clear and the cold resolves. "That transition from clear to purulent to clear again is one that occurs independent of antimicrobial therapy even in uncomplicated URIs," she said.
There are three elements to the normal physiology of the sinuses. They are: the patency of the ostea, the intactness of the mucosiliary apparatus and the quality and quantity of secretions. Paranasal sinuses retain secretions because of an obstruction of the ostea, an impairment of the ciliary apparatus or a reduction in the number of cilia.
"In the face of an obstruction of the ostea outflow tract, bacteria begin to multiply, and we have the situation of an acute bacterial or suppurative paranasal sinusitis," she explained.
"There are two common clinical presentations that should make you think that maybe your patient is suffering from bacterial sinusitis," she said. They are onset with persistent symptoms or onset with severe symptoms.
Onset with persistent symptoms is the most common presentation. These are respiratory symptoms that last more than 10 days but less than 30, which have not begun to improve. Most uncomplicated URIs last about five to seven days, with symptoms peaking and beginning to improve.
If the symptoms don't begin to improve around day 11, the patient may be suffering from a secondary bacterial infection. These respiratory symptoms include any quality or quantity of nasal discharge and/or day time cough. The nasal discharge can be thick or thin, watery or purulent. The cough, which can be wet or dry, must be present during the day, although parents may complain that the cough is worse at night.
"Children who present with persistent symptoms on the whole, often do not look very ill," she said. Sometimes there can be a low-grade fever, but most often, there is no fever, headache or facial pain. Parents may report that there is some periorbital swelling in the morning, but it reduces as the day progresses. "So what brings them to your office is not that they look very ill and not that they are going to die if they are not recognized and treated, but that their symptoms have simply not begun to improve," Wald said.
A less common presentation is onset with severe symptoms. These are high fever a temperature of at least 39.8 C and a large quantity of very purulent nasal discharge.
"What defines this as a syndrome is a combination high fever, which in general does not last more than a day, and purulent discharge which usually does not come on until several days into the cold when they occur together," she said.
You can express your views on this article, or other relevant themes, in the Infectious Diseases in Children Specialty Forums.