Healthy Living

How is Sinusitis Diagnosed?

How physical examination, lab tests, and high-tech tools help us diagnose sinusitis

How is Sinusitis Diagnosed?

Key Takeaways

  • Sinusitis picks up from the infection triggered by cold and flu viruses, bacteria and fungi, and lingers on even after the cold virus has done the damage and moved on.
  • A diagnosis of sinusitis must involve a closer look at chronic ailments that stress the immune system.

Diagnosing sinusitis can be a tricky affair, considering that the symptoms closely resemble those related to colds and the flu. Very often, sinusitis develops from the infection triggered by cold and flu viruses, bacteria and fungi, and often lingers even after the disease-causing microbes have done the damage and moved on.

Chronic conditions (lasting 3 months or longer) like asthma and allergic rhinitis are also triggers that provoke recurring attacks of sinusitis. Diseases such as AIDS, diabetes and certain medicines used in treating cancer weaken the immune system and make the sinuses prone to infection. For this reason, the diagnosis of sinusitis must involve a closer look at chronic ailments that stress the immune system.

Symptoms That May Indicate Sinus Infection

  • Excessive flow of mucus through the nasal passage.
  • Mucus secretion that changes color - from white to greenish yellow.
  • Congestion in the nasal passage, making it difficult to breathe.
  • Dull ache and heaviness around the eyes and cheeks.
  • Headaches that recur with increasing frequency.
  • Tooth pain following a root infection, radiating pain in the jaw line.
  • Drainage of mucus into the throat, followed by coughing and sore throat.
  • Sinus tissue inflammation and fever.

Diagnostic Techniques That Are Useful in Detecting Sinusitis

1. Medical History and Physical Examination

One or more risk factors may be aggravating the sinuses and causing recurring infection. As the first stage of medical evaluation, the doctor will discuss the medical history of the patient to assess the impact of various risk factors the patient may face. Some procedural information taken may be:

  • Noting the frequency and duration of respiratory tract infections, past and present, and whether the episodes are seasonal or work-related.
  • History of infections that don't respond well to antibiotics, and may require more advanced analysis and stronger remedies.
  • History of smoking and possible workplace exposure to atmospheric pollutants.
  • The frequency of air travel, particularly in the periods prior to infections.
  • Dental problems and corrective surgeries undergone, especially in the upper row of back teeth.
  • A complete review of all medicines taken in the past for signs of medication-induced sinus aggravation.
  • The presence of structural abnormalities in the nasal passage that become barriers to the normal flow of mucus.
  • Signs of facial or head injuries or direct nasal damage sustained in falls or fights.
  • History of conditions like fibromyalgia that mimic the symptoms of flu-like tenderness in the facial muscles and bones, and headaches accompanied by extreme fatigue and inability to sleep.
  • Parents or grandparents that had allergies, skin disorders, and weaker immune systems. Cystic fibrosis, if present in the family, is a hereditary disorder that creates extreme congestion in respiratory organs and thickens mucus buildup. In Immotile cilia syndrome, a person is predisposed to cilia (epithelial hair) that are severely weakened and fail to clear mucus.
  • Small children attending nursery or day care centers will be more likely to develop infections. Children carrying symptoms for longer than 14 days may have acquired a chronic condition that may be cleared up with antibiotics, or failing that, may be recommended corrective surgery.

The Hands-On Examination

The doctor gently presses or taps the face above the sinuses to detect pain that signals sinusitis. Another simple technique is pressing a torchlight against the cheek to observe if light reflects off the roof of the patient’s mouth – if light shines through, it would indicate a healthy sinus devoid of mucus secretions, and if the light is blocked, one may presume the airways are blocked. These techniques are not foolproof as sometimes pain and trans-illumination will not clearly indicate sinusitis. 

2. Imaging Tools

X-rays, CT scans, and MRI scans are far more effective in detailing the prevailing situation inside the sinuses and air passages. If for instance, the sinus tissue is swollen and protruding into the cavities and causing blockages, the imaging tools will be quick to pick it up. Imaging will also detect nasal polyps, which are bulbous protrusions that block the passage of mucus, creating a great deal of nasal congestion, which in turn traps infection within the sinuses.

3. Airways Tissue Culture

Sometimes, the patient may not respond as effectively to medication as doctors anticipate. The surgeon extracts a sample of epithelial tissue from the upper nasal passage for cytological analysis. Once the root cause of the infection, whether bacterial, viral or fungal, is diagnosed, corrective therapy focuses on medication that is tailor-made for the aggravator.

4. Endoscopic Examination

In this technique, which is quickly gaining acceptance in the medical fraternity, a thin camera activated endoscope is inserted through the nasal passage with a fiber optic light source illuminating the way. The site is numbed using local anesthesia, and a decongestant applied to clear the airways before inserting the lighted endoscope. The procedure is usually performed by an otolaryngologist or ENT specialist.

An endoscopic evaluation gives a firsthand view of the underlying issues confronted by chronic patients. The onsite visualization may reveal hidden abnormalities that can be tackled with medication or may require corrective surgery.

  • The inner mucus membrane lining the airways may appear reddish and inflamed.
  • Thick, dark-colored mucus may be oozing out of the openings of sinus cavities.
  • Large membranous protrusions called nasal polyps may be blocking the free flow of mucus.
  • The nasal septum bifurcating the nasal passage may appear thickened or deviated in parts, obstructing the drainage of mucus.

5. Testing for Allergens That Trigger Sinusitis

Allergic Rhinitis (Hay Fever) causes many of the symptoms peculiar to sinusitis. It is triggered by flower pollen, dust mites, pet hair and a host of other factors. An allergy skin test enables the doctor to rule out or confirm up to forty different causative factors. Such a screening test that identifies allergens enables a methodical follow-up through targeted medication.

In vitro (meaning blood) testing of Immunoglobulin E antibodies ((IgE) also gives an accurate indication of inflammation caused by allergens. When we are dealing with chronic stages of infection that may be slow to heal, additional tissue biopsies and cytological studies of mucus sampled from the airways may also be conducted to confirm sinusitis and identify the aggravator.

6. Blood Tests

The purpose of blood tests is to zero in on infections, because any sign of acute infection (bacterial, viral or fungal) triggers a proportionate rise in blood count of white blood cells in the blood. Hay Fever, for example, boosts the count of specialized cells called Eosinophils. Blood testing also helps in ruling out conditions like cystic fibrosis, which have the effect of thickening mucus secretions, making them more difficult to drain.

The presence of high levels of the C-reactive protein indicates high levels of inflammation in the body, possibly triggered by microbial infection. The erythrocyte sedimentation rate helps in assessing the degree of inflammation in the body. When proteins combine to form clumps or denser masses, they cause red blood cells to sediment (fall) faster, and a high sedimentation rate indicates a higher level of inflammation.

When the chief symptoms are inconclusive, and it becomes difficult to complete an accurate diagnosis, a new diagnostic tool called SELDI-TOF-MS enables doctors to analyze a small blood sample to map its protein profile. The protein profile of a patient, which is unique like a fingerprint, is helpful in identifying chronic sinusitis with almost 80 percent accuracy.