Sinusitis presents as a blocked nose with postnasal discharge, headache, pain behind the eyes, in the cheeks, jaw and sometimes teeth, redness of the eyes and nose, watery eyes and sore throat with cough. There may be hyposmia and a feeling of pressure behind the face, particularly when bending forward. Sometimes the patient may also have a fever, muscular pain and halitosis (foul smelling breath).

Acute sinusitis is diagnosed clinically but its evaluation may include the following tests [7]:

• Biopsy of paranasal sinuses
• Nasal cytology
• Testing for ciliary dysfunction
• Complete blood count
• ESR

Imaging 

Imaging studies are not required to diagnose sinusitis. In complicated cases, a CT scan and nasal endoscopy may be conducted.

Test results

Typically tests results are not awaited to confirm the diagnosis and start treatment because sinusitis is a clinical diagnosis. Nasal cytology may help identify the causative organism as viral or bacterial so that appropriate antibiotics or antivirals, respectively, may be prescribed.

AVRS typically resolves within 10 days and ABRS may also resolve spontaneously within the first 10 days of infection, so patients who present with fewer than 10 days of symptoms in general should be managed with supportive care only [8]. It includes painkillers for headache and facial pain, hot steam to open clogged up ostia and increased intake of warm fluids. Antihistamines cause the sinuses to dry up but sometimes cause excessive drying, as well as have other side effects like drowsiness and xerostomia, so their use for the treatment of acute sinusitis is generally not recommended [9].

If the infection persists for more than a week or is very severe, mechanical irrigation with buffered hypertonic saline solution may help reduce the need for analgesics and improve overall patient comfort [10]. Irrigation is recommended for people suffering from frequent sinus infections.

Sinusitis has an excellent prognosis. Studies suggest that 40% to 69% of patients suffering from ABRS may clear their infection spontaneously [6]. Whatever the underlying cause, acute sinusitis persists for 3 to 10 days only and then resolves on its own. In some rare cases, it may progress to chronic sinusitis, which also has an excellent prognosis and is easily and effectively treated with antibiotics or antiviral drugs.

Sinusitis may be due to a viral infection, such as infection from Rhinovirus, Adenovirus, Influenza virus A and B, Parainfluenza virus, Coronavirus or Respiratory syncytial virus resulting in acute viral rhinosinusitis (AVRS). It may also be caused by a bacterial infection, such as from Staphylococcus aureus, Staphylococcus pneumoniae, Haemophilus influenzae or Pseudomonas aeruginosa causing acute bacterial rhinosinusitis (ABRS). Acute viral upper respiratory tract infections are considered to be the most important risk factor for the development of ABRS [1].

Some fungi have also been implicated in the etiology of sinusitis but fungal sinusitis is a rare condition. Whatever the causative factor may be, the infection can be primary, affecting the paranasal sinuses directly, or it may be secondary, a result of an upper respiratory tract infection. The blocked sinuses have a negative sinus pressure and a reduced partial pressure of oxygen which makes the cavity ideal for the microorganisms to settle and multiply.

Chronic rhinosinusitis (CRS) is defined as an inflammatory condition involving the lining epithelium of the paranasal sinuses, which persists for at least 12 weeks or longer [2]. It is characterized by persistent nasal discharge or nasal blockage, headache and facial pain.

Incidence

Sinusitis is an extremely common condition with an incidence of over 24 million cases every year in the United States [3].

Age

Sinusitis affects young and old alike. It does not have a predisposition to any particular age group.

Sex

It occurs equally in both sexes but infectious sinusitis is more common in females because they are more prone to close contact with children having infections.

The paranasal sinuses develop as outpouchings of the nasal cavity, with the first sinuses appearing between the 3rd and 4th months of gestaton [4]. They are air-filled cavities extending from the skull to the alveolar process and are lined by pseudostratified ciliated columnar epithelium having mucus producing goblet cells. They include the frontal sinus, anterior and posterior ethmoid sinus, maxillary sinus and sphenoid sinus. All sinuses drain into the nasal cavity via openings called ostia. Ciliary activity is necessary for drainage of secretions from the sinuses into the nose, particularly from the maxillary sinus because the ostia are located high up on the medial walls of this sinus [5].

If any one or more of these paranasal sinuses become blocked and congested, the normally sterile mucus is prevented from draining into the nasal cavity via the ostia. The filling up of the sinuses with mucus results in negative sinus pressure which promotes the development of an infection. The viral, bacterial or fungal pathogens inhabit the congested sinuses and sinusitis develops. Some allergins such as pollen grains or animal fur may cause the sinuses to become irritated resulting in excessive mucus production which then blocks up the cavities causing sinusitis.

Sinusitis may be prevented by intake of appropriate fluids and good oral hygiene. Upper respiratory tract infections should be promptly and properly treated

Sinusitis, or more appropriately rhinosinusitis, is the inflammation of the mucosa of the paranasal sinuses which presents as features similar to influenza. It is a common household occurrence and affects people of all ages, races and ethnicity. Paranasal sinues are hollow bony cavities that help reduce the weight of the skull as well as humidify air during respiration. If any of these sinuses become blocked, the mucus produced by the goblet cells present in these sinuses is unable to drain out, the nasal cavity becomes congested and sinusitis ensues. Commonly, the condition is due to external pathogens, as discussed below.

Definition

Sinusitis is a condition in which the lining membrane of paranasal sinuses, which are hollow air-filled cavities present in the skull, become infected and congested with mucus.

Cause

Sinusitis may be viral, bacterial or fungal or it may be due to an upper respiratory tract infection. Sometimes allergens like pollen grains and animal fur may cause overproduction of mucus which may become infected resulting in sinusitis.

Signs and symptoms

It presents with a blocked and congested nose, thick, postnasal discharge, headache, pain behind the eyes, in the jaws and teeth, red watery eyes and fever. There may also be sore throat and cough.

Diagnosis

Diagnosis of sinusitis is purely clinical. Laboratory tests may help in identifying the causative agent.

Treatment

Treatment is mainly supportive as most cases of sinusitis resolve by themselves. However, it may be treated with antibiotics or antiviral drugs.

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