Cacosmia is the perception of a foul odor in the nose. “It is not always easy to differentiate from phantosmia, which is the feeling of a non-existent (sometimes foul-smelling) odor and parosmia. In the latter case, as a sign of olfactory nerve damage, the perceived odor does not match the real odor,’ the ENT explains.

Cacosmia: What are the symptoms?

“In addition to the perception of an abnormal odor, which is also felt in the nasal secretions and which can be bilateral or unilateral, there can also be pain of sinus location, below the eyes, under orbital or suprorbital, with sometimes even nosebleeds,” Dr. Hadjej explains. Cacosmia is also most commonly associated with nasal obstruction and purulent rhinorrhea.

Causes of cacosmia: a sinus origin in most cases

Cacosmia is never caused by the olfactory nerve, but its main cause is a sinus infection. This may be a bacterial complication of acute sinusitis (as occurs after rhinitis, but more commonly after a tooth abscess in a molar or premolar). ‘In some cases, an apical granuloma may be the cause. When the abscess drains into the maxillary sinus, it will give symptoms of sinusitis with a dirty nasal discharge and cacosmia,’ explains the specialist.

In addition to acute sinusitis, cacosmia can be caused by chronic sinusitis, which can have any number of causes. ‘Causes include aspergillosis of the maxillary sinus, which is the development of a mycotic infection (aspergillus) on dental paste in the maxillary sinus, leading to sinusitis and repeated infections,’ Dr. Hadjedj explains.

In children aged 2 to 4 years, a foul-smelling odor should cause the nose to look for a foreign object that may have caused superinfection. There are also exceptional causes, such as a large car accident that will cause easy trauma. The teeth may then become incarcerated in the sinus.

How to diagnose cacosmia?

“In any case and regardless of the suspected cause, if there is a bad odor in the nose, it is an almost systematic indication to have sinus scans done,” the doctor says. During the ear, nose, and throat examination, the specialist does nasal endoscopy to locate the site of infection and look at areas of drainage in the various sinuses.

How to treat cacosmia?

Treatment, of course, is directed at the cause. ‘If it is acute bacterial sinusitis,

Treatment of sinusitis with antibiotics and topical care may suffice. But we still do a scan to check,’ Dr. Hadjedj recommends. When sinusitis is caused by teeth, the tooth and infection are treated. If an aspergillus infection is the cause, the sinus should be surgically opened to remove the aspergillus. Also read:

‘There are more serious, atypical sinusitis, especially in immunocompromised people. Fungal infection of the sinuses may require hospitalization and antifungal treatment with veins. But this is still rare.’