World Rare Disease Day 2023: A rare disease is an ailment that affects a small percentage of the population. Majority of the rare diseases are are genetic in nature. According to the World Health Organization (WHO), a debilitating lifelong disease or disorder condition with a prevalence of 1 or less, per 1000 population is defined as a rare disease. Studies suggest that of all cases of rare diseases across the globe, around one-third occur in India.
In 2017, India formulated a National Policy on Rare Diseases (NPRD) but it lacked clarity on disease coverage, patient eligibility, and cost-sharing. Consequently, a revised policy was released in March 2021. About 80 percent of rare diseases are believed to be genetic in origin, while 70 percent start in childhood.
Epidemiological data for rare diseases is collated by the National Registry for Rare Diseases, maintained by the Indian Council of Medical Research (ICMR). Until 31 October 2021, 4,001 different rare diseases had been recorded. According to health experts, only 5 percent of rare diseases worldwide are treatable.
Here are some rare diseases prevalent in India:
Chorea-acanthocytosis, also called choreoacanthocytosis is a rare hereditary disease caused by a mutation in a gene that directs structural proteins in red blood cells. The rare disease leads to effects like epilepsy, behaviour changes, muscle degeneration, and neuronal degradation similar to Huntington’s disease. The average age of onset of symptoms is 35 years. The disease is incurable and inevitably leads to premature death.
Addison’s disease, or hypercortisolism is a rare disorder which occurs due to the insufficient production of the steroid hormones-aldosterone and cortisol by the outer two layers of cells present in the adrenal gland. This disease can affect all age groups and both sexes. Around 40-60 people per million of the population are known to be affected by this disease. In India, it is known to affect 1 in 100,000 people.
It is a rare genetic neuro-developmental disorder characterised by severe developmental delay, sleep disorders, jerky movements and frequent laughter. The syndrome is caused by an abnormality in a region of chromosome 15 and it’s usually not recognized at birth. AS is typically diagnosed between the ages of 3 and 7. The main characteristics of this syndrome are delayed motor skills, minimal or absence of speech, developmental delay, ataxia (shaky and unsteady movements), seizures, constant happy behavior that includes frequent laughing, smiling and excitability.
It is a disease that affects mainly the nervous system and immune system. It is Classic A-T is characterised by cerebellar ataxia , ocular telangiectasia, immunodeficiency(mainly low IgA), frequent infections and high risk for malignancy(specifically leukemia and lymphoma). Children with the disease typically present with imbalance while walking, recurrent respiratory infections and a history of developmental delay. In some patients, involuntary movements and intellectual disability may also be seen.
Congenital Hyperinsulinism (CHI) is a rare genetic disorder of pancreatic β-cells that secrete excess amount of insulin causing severe persistent hypoglycemia (low blood glucose) in new-born babies and children. It causes repeated episodes of hypoglycemia because of dysregulated insulin secretion during low blood glucose concentrations in newborn babies and children. As a result, insulin suppresses ketone bodies formation and this unavailability of glucose and alternative fuels increase the risk of brain damage in these patients.
Cryopyrin-Associated Periodic Syndrome (CAPS)
Cryopyrin-associated periodic syndrome (CAPS) is a rare hereditary inflammatory disorder. Cryopyrin-associated periodic syndromes (CAPS) are three very rare diseases related to a defect in the same gene. The three diseases are: Neonatal onset multisystem inflammatory disease (NOMID), Muckle-Wells syndrome (MWS), and Familial cold autoinflammatory syndrome(FCAS). The symptoms and severity of CAPS vary by disease. This disease is characterized by symptoms that come and go, and include Fever, rash, sore or red eyes, fatigue, muscle or joint pain and severe headaches with vomiting.
Cushing’s syndrome is a disorder that occurs when your body is exposed to hormone cortisol over a long period of time. The most common cause is the use of steroid drugs, but it can also occur from overproduction of cortisol by the adrenal glands. Common symptoms of this condition include: weight gain and fatty tissue deposits, particularly around the midsection and upper back, in the face (moon face), and between the shoulders (buffalo hump), pink or purple stretch marks (striae) on the skin of the abdomen, thighs, breasts and arms, thinning, fragile skin that bruises easily and slow healing of cuts, insect bites and infections among others.
Cystic fibrosis is a genetic condition that affects multiple body systems including the lungs and pancreas, causing the most common symptoms of frequent lung infections and digestive problems, diarrhea and failure to gain weight. Cystic fibrosis also affects other organs such as the liver, nose and sinuses and sweat glands. According to reports, introduction of precision medicine in Cystic Fibrosis targeting the CFTR abnormality at the cell level, has led to dramatic improvement in Cystic Fibrosis patients aged 12 years and above. However, these drugs are very expensive and not available in India currently.