Jab that goes up your nose to restore smell

Jabs of blood into the nose may offer new hope to those who have lost their sense of smell. a study found that, after a single injection, patients were able to detect strong odours including coffee and garlic.

after their fourth injection, most of the five study participants had their ability to smell totally restored.

an estimated 3 million people in this country suffer from anosmia, or a severe loss of smell. It occurs as a result of damage to the olfactory sensory nerve cells located in a small patch of tissue, the olfactory epithelium, which is found inside the nose, 7cm up from the nostrils.

Chemical molecules that carry smells dissolve in mucus in this area — receptor nerve cells then send signals via the olfactory nerves to the olfactory cortex in the brain. but if the receptor nerve cells are damaged, they do not readily regenerate.

There are numerous causes of a loss of smell: from chronic sinusitis to nasal polyps and head injury. It’s more common among the elderly, as nerve cells in the nose degenerate with age.

The new jabs work by encouraging the nerve cells to regenerate, according to the researchers from semmelweis University, budapest. They contain platelet-rich plasma (PRP). Plasma is the liquid part of blood — it is made up of red cells, white cells, and platelets. In turn, platelets consist of proteins called growth factors, which play an important role in the growth of new tissue.

Platelets are key to the new treatment. First, blood is taken from a patient’s arm and spun in a machine to separate the platelets and plasma — these are then injected (under local anaesthetic) into the smell-related tissue at the top of each nostril.

The jabs were tested on five patients with anosmia: all had previously tried treatments such as steroids, oral antihistamines and nasal wash for at least three months without improvement.

They were each given four PRP injections over six months and, according to the results, published in the International Journal of Tinnitus Research, after the first jab they could smell strong odours, and after the second they all could smell moderately strong odours, including orange, oregano and basil.

after the last injection, four of the five said their smell had completely come back, while the fifth could smell many, but not all, odours. none of them lost the sense of smell during the one-year follow-up period, suggesting the effects are long-lasting.

Commenting on the treatment, Professor Jaydip Ray, clinical director and EnT consultant at sheffield Teaching Hospitals and sheffield Children’s Hospital, said: ‘ This is an unusual experimental treatment, which seems to have given a good result and hope to a small number of patients with complete loss of smell. However, this needs to be tested further with a more rigorous study design before it can become widely available.’

mEanWHILE, another novel type of jab could help treat tingling in the hands. Injections of diluted dextrose, a form of sugar derived from starch, are being tested for carpal tunnel syndrome ( caused by nerve compression in the wrist) and ulnar neuropathy (which occurs when a nerve in the arm becomes compressed or irritated).

Four trials involving 200 patients at the Tri- service General Hospital in Taiwan will test the jabs for both conditions.

It’s thought the dextrose will help by blocking production of a protein that causes inflammation around nerves.