Sinusitis, also known as rhinosinusitis, is the inflammation of the inner lining of your sinuses. Our facial skeleton has four pairs of sinuses: maxillary, ethmoidal, frontal, and sphenoidal sinuses. These sinuses are lined with a thin mucous membrane that performs various functions. When this inner lining is irritated due to an infectious or non-infectious cause, the mucous membrane produces excessive mucous discharge. This is the primary reason which results in the major symptoms of sinusitis. These symptoms can be short-lasting or long-lasting depending on the pathogenic cause and your immune system.
Many cases of sinusitis are caused by viral or bacterial infections. Rhinovirus, influenza virus, and parainfluenza virus are the most common viruses. Infection caused by these viruses may be accompanied by fever, headache, and other symptoms. Other viruses that cause sinusitis include coronavirus, adenovirus, respiratory syncytial virus, enteroviruses, etc. Among bacterial infections, those caused by Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pyogenes, etc., are the most common ones that affect the inner lining of sinuses. Fungal infections can also be a causative agent in patients with weakened immune systems. Allergic rhinitis, asthma, obstructive sleep apnea, nasal congestion, maxillofacial trauma, or dental abscess formation can be a few other causes of sinusitis.
Sinusitis is divided into three types depending on its duration and recurrence rates. Acute sinusitis is the most common type caused by viral or bacterial infections. It persists for one to two weeks and resolves with prescribed medications and symptomatic care. Chronic sinusitis is associated with multiple factors, including a long-lasting bacterial infection, fungal allergy, or a weakened immune system. It occurs with or without nasal polyps. It persists for longer than twelve weeks and may require surgery if medications have been ineffective.Recurrent sinusitis has similar causes to chronic sinusitis. It may be due to repetitive allergic reactions. This condition can occur multiple times within a year, causing extreme discomfort for the patient.
Major risk factors for sinusitis include allergies, inhalation of a foreign body, asthma, or preexisting respiratory tract infections. Any anatomical deformity such as deviated nasal septum can also increase the risk of developing sinusitis. Dental infections in maxillary teeth can erode the maxillary sinus walls and cause inflammation if not addressed on time. Smoking is another potent risk factor. Gastroesophageal reflux disease may also erode the inner lining of sinuses. Patients with weakened immune systems are particularly at high risk. Sinusitis occurs more frequently in adults over 18 because they have more well-developed sinuses than children. This is unlike most respiratory tract infections that are more frequent among children. It has been noticed that sinusitis is more common among females than males.
Common symptoms of sinusitis include pain and pressure in the affected sinuses, excessive nasal discharge, nasal obstruction, or nasal congestion. These can be experienced with acute and chronic sinusitis since the inflamed mucous lining continues to produce mucous discharge, filling the sinuses. You may feel extreme discomfort primarily upon lying down. Infectious nasal discharge may contain pus as well. Inflammation of maxillary sinuses also exerts pain on maxillary teeth in some cases. Sinusitis can also cause an increase in ear pressure and fullness. Other symptoms include fever, headache, dizziness, anosmia (decreased or absent sense of smell), postnasal drip, and halitosis (bad breath).
The diagnosis of sinusitis requires a detailed history and thorough clinical examination. Acute viral or bacterial sinusitis is usually diagnosed based on symptoms alone. Bacterial sinusitis can be distinguished by the presence of pus in nasal discharge. Tissue samples can be taken to identify the pathogenic organism. If sinusitis persists for more than 12 weeks, a CT scan is usually recommended to visualize the affected sinus. A nasal endoscopy might be performed to search for any anatomical abnormalities or other causes in rare cases.
Sinusitis needs to be differentiated from other types of headache, including migraine, cluster type headache, trigeminal neuralgia, atypical facial pain, etc. This is typically done by differentiating based on pain upon bending over or lying down. Other diseases that might mimic the symptoms of sinusitis include temporomandibular disorders, myofascial pain, dental abscess, allergic rhinitis, asthma, etc.
The majority of the cases of sinusitis do not require any particular treatment except for symptomatic care. Antipyretics, analgesics, topical or nasal corticosteroids, and antibiotics might be prescribed depending on the causative pathogen, severity, and duration of the symptoms. Supportive care, which includes fluids intake, saline irrigation, steam, etc., might relieve some of the symptoms. The surgical option, which includes functional endoscopic sinus surgery, is only recommended in cases of chronic sinusitis that have not responded to long-term use of medication and supportive therapy.
Viral sinusitis usually does not require any medication except for antipyretics such as paracetamol or analgesics such as aspirin, diclofenac, etc., to relieve symptoms. Bacterial sinusitis requires antibiotics such as penicillin, amoxicillin, etc. The recommended antibiotic course should be completed. Intranasal and topical corticosteroids such as those containing dexamethasone might improve symptoms. Antihistamines such as loratadine etc., are prescribed in case of allergic sinusitis.
Most viral and bacterial sinusitis cases improve within one or two weeks, especially if accompanied by prescribed medications and supportive care. Rare cases have been reported where severe respiratory complications and sinusitis lead to mortality.
Basic prevention methods to reduce the chances of developing sinusitis include avoiding close contact with infected individuals, wearing a face mask in crowded areas, washing hands frequently, and using alcohol-based sanitizers. Most of these infections spread from air droplets or oral secretions from an infected person; therefore, sharing toothbrushes or utensils should be avoided as well until their recovery. Few viruses and bacteria associated with sinusitis have vaccinations available such as the influenza vaccine. If they are available in your country, it is beneficial to get vaccinated. Active or passive smoking should be avoided as well to reduce its risk.
Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available. Last reviewed by Dr.Saad Zia on May 29, 2023.
Sinus Infection (Sinusitis) | Antibiotic Use | CDC
Sinus Infection | Causes, Symptoms & Treatment | ACAAI Public Website