Inflammatory and infectious causes of sinusitis

Inflammatory and infectious causes of sinusitis refer to factors that are caused by infections and may cause inflammation or redness in the sinuses. They include:

• Allergies
  Any substance that produces an allergic reaction is sure to cause inflammation in the sinuses. Those substances are called allergens, they include pollen, animal dander, mold spores, dust mites etc. When allergens come into contact with the lining of the nose, sinuses, eyes and throat the body's immune system will try to create a barrier against these allergens and this will result in the swelling and blockage of the ostium (opening of the sinus cavity) preventing drainage of mucus and causing an obstruction from within sinus cavity.
  
  Sometimes the immune system mistakenly tries to protect the body against harmless substances and in the process, causing an allergic reaction. In the United States, the most prevalent pollen comes from ragweed. It begins pollinating in late August and continues until the first frost. In addition, 14.6 million Americans have asthma, which is often accompanied by hay fever.
  
  
• Viral Infections
  The most common virus that usually cause a viral infection are known as an upper respiratory infections or a common cold, these include rhinovirus, adenovirus, influenza and para-influenza viruses. A viral infection normally lasts 7-14 days and is preceded by an acute sinus infection. In some cases the viral infection can persist and become chronic sinusitis. Viral infections do not cause symptoms of sinusitis per se, they do cause inflammation of the sinus mucus linings. This inflammation caused by a viral infection can however increase your chances of developing sinusitis.
  
  During a viral infection, mucus production in the nose increases causing swelling of the nasal passages which obstruct the ostium preventing proper flow of air and mucus, resulting in pain. When you have blocked sinuses, you are more prone to a secondary bacterial infection. About 2-3% of colds in adults and 20% in children lead to a bacterial infection.
  
  
• Bacterial Infections
  Streptococcus Pneumoniae and Haemophilus Influenzae are the most common bacteria isolated during a sinus infection. These bacteria are often found in the upper respiratory tract of healthy people, they only cause a problem when the body's defenses are weakened or when drainage from the sinuses becomes blocked, resulting in the multiplying of trapped bacteria.
  
  Symptoms of bacterial sinusitis are almost identical to those of a viral infection, although bacterial sinusitis symptoms are usually more severe and last longer. Acute bacterial sinusitis is often caused by the bacterium Streptococcus Pneumoniae, which is usually resistant to standard doses of amoxicillin (an antibiotic drug used to treat infections). The better option for treating this bacterium is through a Pneumococcal Vaccine that prevents most, but not all infections caused by Streptococcus Pneumonia.
  
  
• Nasal Polyps
  Nasal polyps are benign growths or tissue masses that project from the lining of normal tissue. Nasal polyps are common in people who have asthma, and approximately 2% of the population has nasal polyps. Nasal Polyps are often a response to the inflammation of the mucus lining and tend to recur even when surgically removed. Any allergy or inflammation will cause a nasal polyp to swell and further obstruct the opening of the sinuses.
  
  About ¼ of all chronic rhinosinusitis patients have nasal polyps that are generally related to fungus. These nasal polyps sometimes block nasal airways and create breathing difficulties. They may also inhibit proper drainage from the sinus cavities, creating stagnant secretions that stay in the sinuses and become infected which leads to sinusitis.
  
  It should be noted that although nasal and sinus polyps are rare in children, they should be taken very seriously. Any child with nasal and sinus polyps should be screened for Cystic Fibrosis, Kartagener's Syndrome and Allergic Fungal Sinusitis.
  
  
• Fungus Infection
  Fungal growths are present in many cases of chronic sinusitis. The causes of a fungus infection are not clearly identified but their presence may be due to the overuse of antibiotics. Fungal infections are becoming very common and are often due to a weakened body defense mechanism.
  
  Fungal growths on the sinus lining absorb their food in the sinus cavities, they cannot produce their own food so they consume organisms that are no longer living which cause a fungal infection. Like bacteria, fungi has the ability to consume and break down complex organic substances.
  
  Fungus balls commonly affect the maxillary sinuses and presents as a typical sinus infection. They have thick pus with dense hyphae (which are filaments that make up the body of a fungus). The fungus ball varies in size from smaller than a millimeter to the size of the sinus cavity, requiring surgical intervention. Fungal sinusitis can be of an allergic nature that tends to spread all over the sinuses.