[0.1% Fighting Rare Diseases] ① "Late Corrected Brain Lesion Misdiagnosis... Now Nurturing Dream of Becoming a Chef"

[Editor's Note] Each year, about 50,000 people, representing 0.1% of the total population, are diagnosed with rare diseases. Early diagnosis is difficult, so most patients only realize they have a rare disease after reaching adulthood. Treatments are often expensive and not covered by health insurance. Through the voices of rare disease patients and their families, we explore the realities they face and the measures needed for diagnosis and treatment.

Kim Minsu (19), a freshman in the Hotel Culinary Department at Osan University, is a patient with a rare disease called congenital myopathy. Myopathy is a condition where muscle strength in the body and internal organs gradually declines, eventually making walking difficult and causing labored breathing. In severe cases, patients often end up using a wheelchair and later become bedridden. When we met Kim on the 8th, he was able to take the bus alone and attend university orientation (OT) classes quite well. Kim said, "I plan to seriously consider what kind of chef I want to become during my freshman year."

Kim Min-su (19), who suffers from congenital myopathy, and his mother Lee Myung-ja (52) are being interviewed by Asia Economy.

"Accurate Diagnosis Leads to Treatment to Prevent Worsening... Misdiagnosis as Brain Lesion"

Kim’s mother, Lee Myungja (52), attributes her son’s stable condition and ability to live independently as an adult to the precise diagnosis of myopathy through genetic testing conducted at Gangnam Severance Hospital in 2017. Lee said that immediately after birth, Kim underwent genetic testing (disease diagnosis), but due to limitations of diagnostic tests at that time, he was diagnosed with a ‘brain lesion (central nervous system disorder caused by brain damage).’ Lee recalled, "Minsu was a child who could learn two to three things when taught one, so I was sure it wasn’t a brain lesion," adding, "I just thought he was a bit weaker than others."

Later, when Kim’s older brother, Kim Mingyu (25), experienced a life-threatening episode due to difficulty exhaling properly during the night, medical staff advised them to get genetic testing. They visited Gangnam Severance Hospital, where the brother was diagnosed with hereditary myopathy, and Kim received the same diagnosis. Because it is a rare disease, diagnosis often comes after a long time and after symptoms have somewhat manifested. However, Kim was fortunate. His lung capacity is about 40-50% of a normal person’s, which is low, but still significantly higher compared to other myopathy patients. This means the progression of his myopathy was not severe. Recently, the frequency of his respiratory rehabilitation visits to the hospital has been greatly reduced to once every six months.

Kim Min-su taking a commemorative photo with friends at his high school graduation ceremony.

Although there is no developed treatment for myopathy yet, receiving a diagnosis and undergoing respiratory rehabilitation therapy can significantly slow disease progression. The Respiratory Rehabilitation Center at Gangnam Severance Hospital, established in 2008 in cooperation with the Life Insurance Social Contribution Foundation, supports and treats myopathy patients by providing respiratory assist devices to prevent weakening of lung muscles. For patients with mobility difficulties, home nursing services are also offered. Professor Choi Wona of Gangnam Severance Hospital said, "Textbook life expectancy for myopathy patients is 20 years, but since respiratory rehabilitation therapy was introduced in Korea in the 2000s, many patients live 40 to 50 years or more."

Rare Disease Patients 0.1%... Early Diagnosis Still a Long Way Off

With advances in medical technology, many rare disease patients can live normal lives like Kim if they receive appropriate treatment. For this, it is best to receive a proactive diagnosis of rare diseases through genetic testing at a young age. However, the vast majority of rare disease patients still receive late diagnoses. According to the ‘2020 Rare Disease Patient Statistical Yearbook’ published by the Korea Disease Control and Prevention Agency in November last year, 50,231 people were diagnosed with rare diseases in 2020, representing 0.1% of the total population. Among these, for diseases with more than 200 cases (50 diseases), 92.65% of patients were diagnosed after age 20. This means 9 out of 10 people only learn they have a rare disease after becoming adults. Although many treatments exist and early diagnosis is preferable, only 0.84% of diagnoses were made in children under 1 year old. Diagnosis rates were also low in ages 1-9 (1.72%) and 10-19 (4.79%). Many symptoms are mistaken for other diseases, and there is a shortage of specialists dealing with rare diseases, resulting in a severe lack of diagnostic infrastructure.

The government is aware of the importance of early diagnosis of rare diseases. Since 2018, the number of nationally managed rare diseases designated for support has been expanded annually. The number of target diseases increased from 926 in 2018 to 1,165 currently. For ultra-rare diseases, which are very difficult to diagnose (currently 299 diseases), the number of institutions providing diagnosis and financial support has increased to 72. Also, since most diagnostic infrastructure is concentrated in the metropolitan area, causing non-metropolitan patients to often stay overnight at hospitals, 11 regional rare disease centers have been operated since 2019.

There is still a long way to go. Diagnosis is only the beginning of many challenges rare disease patients face. Many rare diseases are not registered as nationally designated management targets. Severe eosinophilic asthma, generalized pustular psoriasis, and cold agglutinin disease are representative examples. Kim Jina, director of the Korea Rare and Intractable Disease Association, said, "Being registered as a rare disease allows patients to receive special medical expense reductions, lowering treatment costs to one-tenth, which helps alleviate economic burdens." Professor Choi Wona added, "Even after diagnosis, many patients stop treatment due to distance from hospitals or financial burdens. Continuous follow-up and management after diagnosis are very important."