The smell of illnesses

Today is my mother’s birthday. She would have been 97. She died of a kidney ailment in 2000 at the age of 78. The other day, while standing in front of the small crypt that bore her remains, I tried to summon from memory the last time we talked. While recalling the tone of that familiar voice conveying her final instructions, I remembered how distracted I was by the pungent smell that seemed to emanate from her skin. It was the faint odor of urine.

This smell had been explained to me by a medical doctor as the result of end-stage renal disease. My mother was on peritoneal dialysis for a year and, in her case, the procedure became increasingly insufficient to help her body get rid of the toxins normally expelled in the urine.

She told me that she was aware that her time was up, and that she did not wish to prolong her life by dialysis. I brought up the idea of a kidney transplant, but she would not hear of it. By that time, she had outlived my father, who died in 1980 at age 59, by two decades. There was conviction in her voice, and I had no reason to doubt the determination of this strong-willed woman who delivered 13 children into the world and brought them up almost single-handedly.

The scents I associate with my mother, all from my childhood, include the smell of smoke from burning wood, of sautéed vegetables and grilled fish, and the mixture of soap, talcum powder and sweat on her olive skin. It is strange but I would sooner recall the way she smelled than the way she looked.

All this comes back to me after reading a fascinating article in the latest international edition of the German online magazine Spiegel Online. There is more to odors than meets the nose. They can help detect the onset of illnesses long before the appearance of their first visible symptoms. The precious time gained may be used to avert the arrival of debilitating symptoms. Right now, with illnesses like Parkinson’s disease, for example, available treatments mainly help patients to manage or control the more problematic symptoms such as violent tremors, the loss of control of bodily functions and dementia. There is no cure yet for this disease, which seems to afflict a growing number of people even at a relatively young age.

The Spiegel article, “The Woman Who Can Smell Parkinson’s,” tells the story of Joy Milne, a Scottish former nurse who quit her job to take care of her late husband as he battled the ravages of Parkinson’s. She emerged from that experience with a validation of her uncanny ability to spot the “musky” scent of this disease, even in people who have yet to manifest the tell-tale symptoms associated with it. Of her “hyperosmia,” which is what this acute sense of smell is called, Milne says that she is somewhere between that of a human and a dog. Here is the link to that two-part article: https://www.spiegel.de/international/zeitgeist/ joy-milne-can-smell-parkinson-s-before-it-is- diagnosed-a-1295601.html#ref>nl-international.

Now 69 years old, Milne started to keep a journal of her husband’s condition when, at the age of 40, he began to show disturbing signs of illness. He had frequent bouts of constipation and had difficulty sleeping. He became moody. These are not, of course, necessarily the early signs of Parkinson’s. But what she remembers most of those early days was the strange scent which grew stronger as the disease progressed. “Musky, sebum musky,” she now recalls.

Musk is a precious scent, used as a base for many perfumes. As with most other descriptions of smells, it is not easy to come up with the right words to describe the smell of musk. In contrast, we have precise words for taste—sweet, sour, bitter, salty, etc. But Milne had the ability to detect the smell of Parkinson’s in a group of people, or from sniffing clothes they have worn.

Simple as it may seem for Milne, the functioning of the olfactory sense is quite complex. Here is how the Spiegel article describes it: “Our scent receptors are located on the mucous membrane inside the nasal cavity. They are protein compounds that are each responsible for only a single odor molecule; they become active when their molecule comes through the nose and binds perfectly. Odorant molecules come in different shapes and sizes and the entire system functions according to the lock-and-key principle.”

A team of scientists led by the chemist Dr. Perdita Barran, working from a laboratory in the Manchester Institute of Biotechnology, are busy trying to develop a machine that could be used to detect the early onset of Parkinson’s disease from the smell that patients emit well before the disease begins to destroy critical brain cells. Milne has been harnessed to teach that machine how to do it through an elaborate series of tests. The project has been appropriately dubbed “NoseToDiagnose.”

Parkinson’s disease was named after the British doctor James Parkinson, who, in 1817, published the article titled “Essay on the Shaking Palsy.” He wrote: “So slight and nearly imperceptible are the first inroads of this malady, and so extremely slow its progress, that it rarely happens, that the patient can form any recollection of the precise period of its commencement.” By the time it is detected through its visible manifestations, many critical brain cells would have already been typically destroyed.

Thanks to her unusual ability, her observational skills and the journal she kept of her husband’s illness, Joy Milne has shown that diseases like Parkinson’s can be smelled years before they appear, thus holding up the hope of a cure not too long from now.

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