Platelet-rich plasma injections restore sense of smell in eight out of ten patients

»A total of eight to nine scientific studies have been conducted, clarifies the ENT specialist. Two years ago, Americans conducted a randomized, placebo-controlled study of loss of smell after Covid-19. They injected one group with PRP and the other with saline. Neither the injector nor the patient knew what was being injected.“

The study shows that after three months, the PRP group had 12 times more recovery than the placebo group.

Study in Belgium

Professor Lechien conducted his own research in Belgium, also in collaboration with French and Italian doctors. “I looked at 80 patients who received PRP injections and 80 who received nothing, not even a placebo. The goal was to see if PRP accelerated the natural rate of recovery.. “

The practitioner explains that in most patients infected with Covid-19, their sense of smell is restored within two to three weeks. “For those who have not recovered after three months, it can take a very long time, even decades, based on other experiences with post-viral, pre-Covid loss of smell.“

Professor Lechien’s research shows that the recovery curve is significantly higher with PRP injections compared to those who follow simple olfactory training. “Progression rate is 80.3% after three months.»

Recovery usually occurs gradually. “Although I have had 5-6 cases that suddenly recovered after a few weeks.»

But American experience shows that PRP injections can have an effect of up to six months. “And today I see that some patients respond after four months.“

For some patients, the loss of smell may be permanent.

Who’s worried?

»Among people who lost their sense of smell during the Covid pandemic, 29% are experiencing effects two years after the illness.“

»Many patients come to me with great hope, but I have no prognostic factor that can tell them whether they will be part of the 80% of patients for whom the treatment works or the 20% for whom it does not work.»

The Americans realized that with three injections the success rate increases to 95%. “I’m not doing this for budget reasons. If health insurance reimbursed everyone for shots, I would get three. There I do one at a time, at the request of the patient“

But the specialist clarifies that of the 80% of those who recover, from 50 to 60% are really very happy.

Why do we lose our sense of smell?

»We have neurons in our nose. The receptors that sense smell are located in our nose, and around them there are a number of cells that supply them with nutrients and keep them functioning properly.– explains the specialist.

According to Dr. Lechien, the main reason for loss of smell is that the virus destroys these supporting cells. “And consequently, the neurons stop functioning properly.“

Then, in people who lose their sense of smell for a long period of time and do not regain it, we find pieces of “transcriptum”. “This is the RNA of the virus that resides in the cells, as if the virus had placed its genetic code permanently in the olfactory cells.»

As a result, every time a stem cell tries to differentiate and reform a supporting cell or odor receptor, the immune system detects the presence of the virus and destroys the cell.

»In a study from the Pasteur Institute, a biopsy of the olfactory clefts was performed two years after contracting Covid. We find viral RNA in people with smell loss, and we also see this in smell loss associated with other viruses, such as influenza.“

Professor Lechien’s hypothesis is that PRP suppresses the immune system’s inflammatory response, preventing it from destroying cells.

200 euros for a special tube

For platelet-rich plasma, a special tube must be used. “These are regeneration tubes. When blood collected from a patient is centrifuged, these tubes isolate the red blood cells at the bottom of the tube. As a result of a chemical reaction, a gel is formed on top of the red blood cells. Above the gel is plasma, and below the plasma are concentrated platelets. It is in platelets that regeneration factors are found.“

Dr. Lechien has been taking only the lower part of plasma for injection for a month now,”because studies have shown that this part is even more enriched in platelets” He hopes he can improve his success rate.

Where is PRP administered? “In the olfactory fissure: This is the highest part of the nose, just below the brain. This is a 1mm wide slot. On the wall separating the two nasal cavities from the nasal septum, there is an olfactory network 2–3 cm long: the famous olfactory receptors. I insert it into the wall of the nasal cavity“

Few places in Belgium

The very first Belgian study of PRP for loss of smell was carried out in Brussels by a young doctor. Currently, this technique is used in Belgium only by Professor Lechien, and also by a young doctor from Brussels under the direction of Professor Lechien in a placebo-controlled study.

Links to smell problems

• Other studies : Studies have also been conducted in Turkey and South America, which showed encouraging results. “But these are not studies conducted with a control group.“, explains Professor Lechien.
• Anosmia “It’s a complete loss of smell,”objectified by test” The specialist distinguishes it from hyposmia – partial objective loss of smell.
• Before and after test : To receive a PRP injection from Professor Lechien, you must undergo two objective tests, before and after, five months apart. “Because when a patient who has lost his sense of smell for two years regains it, he does not immediately realize it. We cannot trust the patient’s simple feelings.“
• Depression : According to Professor Lechien, the study found that long-term loss of smell was associated with a more severe depressive profile. “But whether depression is a cause or a consequence of the loss of smell is unknown.“