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What is sinusitis?

Types of sinuses that could be affected by sinusitis: Frontal, ethmoid, and maxillary.

Sinusitis is an infection of the sinuses near the nose. The sinuses are cavities or air-filled pockets near the nasal passage. Like the nasal passage, the sinuses are lined with mucous membranes. There are four different types of sinuses:

  • Ethmoid sinus: located inside the face, around the area of the bridge of the nose. This sinus is present at birth and continues to grow.
  • Maxillary sinus: located inside the face, around the area of the cheeks. This sinus is also present at birth and continues to grow.
  • Frontal sinus: located inside the face, in the area of the forehead. This sinus does not develop until a child is around 7 years old.
  • Sphenoid sinus: located deep in the face, behind the nose. This sinus does not develop until adolescence.

These infections usually occur after either a cold or an allergic inflammation. There are three types of sinusitis:

  • Acute sinusitis: occurs quickly and improves with the appropriate treatment
  • Subacute sinusitis: does not improve with treatment initially, and lasts less than three months
  • Chronic sinusitis: occurs with repeated acute infections or with previous infections that were inadequately treated, and lasts longer than three months

Symptoms & Causes

What are the symptoms of sinusitis?

The symptoms of sinusitis depend on the age of the child. The following are the most common symptoms of sinusitis. However, each child may experience different symptoms.

In younger children, symptoms may include:

  • Runny nose
  • Lasts longer than seven to 10 days
  • Discharge is usually thick green or yellow, but can be clear
  • Nighttime cough
  • Occasional daytime cough

In older children and adults, symptoms may include:

  • Runny nose or cold symptoms lasting longer than seven to 10 days
  • Drip in the throat from the nose
  • Headaches
  • Facial discomfort
  • Bad breath
  • Cough
  • Fever
  • Sore throat
  • Swelling around the eye, often worse in the morning

What causes sinusitis?

Sometimes, a sinus infection happens after a child has an upper respiratory infection (URI) or common cold. The URI causes inflammation of the nasal passages that can block the opening of the paranasal sinuses and result in a sinus infection. Allergies can also lead to sinusitis because of the swelling of the nasal tissue and increased production of mucus. There are other possible conditions that can block the normal flow of secretions out of the sinuses and can lead to sinusitis including the following:

  • Abnormalities in the structure of the nose
  • Enlarged adenoids
  • Diving and swimming
  • Infections from a tooth
  • Trauma to the nose
  • Foreign objects stuck in the nose
  • Cleft

When the flow of secretions from the sinuses is blocked, bacteria may begin to grow. This leads to a sinus infection, or sinusitis. The most common bacteria that cause sinusitis include the following:

Diagnosis & Treatments

How do we diagnose sinusitis?

In addition to a complete medical history and physical examination, doctors may use these diagnostic procedures:

  • Cultures from the nose or sinus fluid: Laboratory tests that involve the growing of bacteria or other microorganisms to aid in diagnosis
  • Sinus X-rays: Diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film
  • Computerized tomography (CT or CAT scan): A diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce cross-sectional images (often called "slices"), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general X-rays.
  • Blood tests

How do we treat sinusitis?

Treatment of sinusitis may include the following:

  • Antibiotics, as determined by your child's physician (antibiotics are usually given for 10 to 14 days, and sometimes longer)
  • Acetaminophen (for pain or discomfort)
  • Use of a cool mist humidifier in your child's room
  • Nasal drops

Decongestants and antihistamines may not help the symptoms of sinusitis.