Chronic itching can have a big impact on someone's quality of life, but in many ways is poorly understood. Scientists are tackling the head-scratcher of why we itch from a number of angles. (photomystery/Shutterstock/CBC News)
Candice Coghlan, now 38, spent her high school days grappling with persistent itching, particularly on her legs, back, and scalp, unaware that it signaled an underlying health issue. Returning home during her second year of university, she discovered she had lost weight in addition to dealing with skin problems.
A routine blood test revealed alarming results, prompting an urgent visit to the emergency department. The diagnosis was devastating: Coghlan was in end-stage kidney failure. Reflecting on her past, she realized that what she had assumed to be ordinary psoriasis-related itching was actually a symptom of her failing kidneys. The toxins her kidneys couldn't filter were attempting to exit through her skin, causing unbearable itchiness.
Coghlan underwent more than a year of dialysis before receiving a kidney transplant from her mother in September 2009. Almost immediately after the transplant, she noticed the disappearance of the persistent itching.
Chronic itching, a condition that can be associated with deep underlying health issues such as liver or kidney disease, can significantly impact a person's quality of life. Even when the cause is less severe, itching itself can be distressing and poorly understood.
Dr. Rachel Asiniwasis, a dermatologist, often treats atopic dermatitis, commonly known as eczema, in her practice. She emphasizes that the itching experienced by patients can be as debilitating as chronic pain, often affecting mental well-being. Patients with chronic itch frequently exhibit characteristic scratch marks and may develop open sores, increasing the risk of infection. Asiniwasis likens managing eczema to managing diabetes due to its prevalence and impact on daily life, especially during dry winter months when indoor heating exacerbates skin dryness.
Akhil Padmanabha, a PhD student, has been dealing with eczema since birth. His personal struggle with the condition inspired his doctoral research on tracking scratch behaviors, aiming to develop a tool to measure scratching intensity objectively. Padmanabha's prototype, which measures the force and intensity of scratching, could provide valuable insights into the effectiveness of treatments.
The contagious nature of itching remains an enigma for medical researchers. Simply observing someone scratching can induce the same behavior in others. Researchers speculate that itch and pain might share similar pathways to the brain, but the signals are coded differently. Understanding the mechanisms behind contagious itching could shed light on perplexing cases like persistent scalp itching even after nerve dissection surgery.
