Dysosmia: Symptoms, Causes and Treatment

Overview

Dysosmia is a neurological disorder that causes a distorted sense of smell. It is an olfactory dysfunction and the impairment of olfactory stimuli leads to an alteration of the sense of smell. Patients with dysosmia may have difficulty in smelling or detecting any odor. It is common for patients to suffer from anosmia for weeks or months when dysosmia is present. Although dysosmia is not a life-threatening disease, it can lead to some problems that affect people’s life. Loss of smell will cause anxiety, depression and nutritional deficiencies in people. There are several types, or sub-conditions of dysosmia, including anosmia, parosmia and phantosmia. Dysosmia occurs in any race, gender or age group.

Causes

The cause of dysosmia depends on the different types of the condition.

  • Anosmia

Patients with anosmia tend to have no olfactory response to any odor. The condition could be acute or chronic. Acute Anosmia is caused by blockage of the nose or infection of the nasal sinuses and nasal polyps. Constant use of medications, such as antihistamines and decongestants, will lead to nasal blockage. Structural defects in the nose, which include abnormal thinning or thickening of the mucus membrane inside the nose, may also cause a change in the sense of smell. When the olfactory receptor neurons are damaged completely, it could lead to a complete loss of smell.

  • Parosmia

Parosmia is a dysfunction with smell detection. Patients are unable to properly identify an odor’s smell. The causes of parosmia could include contact with toxics substances or a head trauma that affects the olfactory bulb.

  • Phantosmia

Phantosmia is a condition where patients tend to imagine smells that are not real. It is defined as an olfactory hallucination with smell which may occur due to neurological disorders such as Alzheimer’s disease and Schizophrenia.

Other common causes of dysosmia are:

  • Serious head trauma 
  • Poor oral hygiene
  • Mental conditions
  • Infected nasal sinus
  • Medications
  • Migraine
  • Pregnancy

Symptoms

The two main symptoms of dysosmia are distorted olfactory function and loss of olfactory function. Other symptoms may include:

  • Sudden loss of function
  • Sinus infection
  • Polyp in nasal activities
  • Loss of taste
  • Confusion of flavor

Diagnosis

To diagnose dysosmia, the doctor will first ask a detailed medical history of the patient, including questions on whether you have suffered from any head injury or infections of the respiratory system. In addition, some diagnostic techniques are recommended to take, which include nasal cytology, olfactory nerve testing, sinus transillumination, sniffin’ sticks, and University of Pennsylvania Smell Identification Test (UPSIT). Other diagnostic techniques involve use of imaging tests like X-rays or CT scans.

  • Nasal cytology: Nasal allergies like rhinitis can be diagnosed by this technique. The doctor will ask the patients to blow their nose into a piece of plastic wrap. The nasal discharge is collected and will then be sent for laboratory examination to detect the eosinophil count which is responsible for allergy.
  • Olfactory nerve testing: The function of the olfactory nerve can be tested by blocking one nostril and placing a pungent odor under the open nostril for patient’s reaction. The same test is repeated on the other nostril.
  • Sinus transillumination: In this test, a bright light is projected over the patient’s cheek or forehead in a dark room. If the sinuses are clear, a glow on the hard palate of the open mouth or in the areas of the cheek will be observed.
  • Sniffin’ sticks: It is useful in diagnosing Parosmia and Anosmia. It can help doctors measure graded stimulus and observe the response of patients.
  • University of Pennsylvania smell identification test: It involves four self-administered test booklets to trigger your sense of smell, each booklet has ten stimuli within it. Patients pick up one of the booklets and identify the types of odors present within it. This test gives you an easy way to identify the olfactory functions and tells whether you are having an upper respiratory infection or sinusitis.

Treatment

The treatment options for dysosmia are limited. In most cases, the rate of recovery of olfactory senses may vary depending on the type of olfactory dysfunction that a person is suffering from.

Common treatments include topical medications, systemic medications, and application of anesthesia to parts of the nose. In some cases, doctors may perform endoscopic transnasal excision of olfactory epithelium to treat phantosmia. This may restore the olfactory function. There are also some measures can be taken to improve the condition:

  • Lifestyle changes
  • Avoid smoking
  • Avoid drinking
  • Saline spray to clear the nose
  • Straighten the nose structure by taking rhinoplasty
  • Surgery to remove polyp


Keywords: Dysosmia

* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.