Image Credit: Canva
A condition, known commonly as "black urine disease" or Alkaptonuria is a rare genetic disorder involving protein metabolism, and it has its root in the mutation of the homogentisate 1,2-dioxygenase gene, which in turn causes homogentisic acid accumulation in the body. The appearance of dark urine after exposure to air is due to this kind of accumulation; however, a variety of symptoms can be expected, such as joint stiffness, changes in pigmentation, and other long-term health complications. Although the prevalence has been estimated to be between 1 in 250,000 and 1 in 1 million people in the United States, its effects are indeed high on those affected.
Alkaptonuria is an autosomal recessive disease, meaning that the child must inherit a defective copy of the HGD gene from both parents. If both parents are carriers, their offspring have a 25% chance of inheriting two faulty genes and developing alkaptonuria. The condition is genetic but is often not diagnosed for years because it progresses slowly and its early symptoms appear to be harmless.
The most characteristic and common initial symptom of alkaptonuria is dark urine. The reason for this is due to the fact that excess HGA is excreted in the urine and upon oxidation in the presence of air, it gives the urine a brown or black color. Though it is often considered cosmetic, the long-term accumulation of HGA within the connective tissues produces more complicated health problems.
Progressive joint pain and stiffness: The accumulation of HGA in cartilage leads to early-onset osteoarthritis, making movement increasingly difficult over time.
Skin and eye pigmentation changes: Affected individuals may develop bluish or grayish discoloration of the sclera (white part of the eye) and the skin, particularly in areas exposed to friction.
Cardiovascular and respiratory problems: With age, HGA accumulation can lead to valve calcifications in the heart and stiffening of connective tissues in the respiratory tract, which can cause problems in middle and old age.
Decreased mobility and spinal problems: The spine may become stiff and painful due to chronic cartilage degeneration.
These symptoms usually begin to manifest during adulthood, leading to severe complications in a person's 40s or 50s and significantly affecting the quality of their life.
Because of its rarity, alkaptonuria is often mistaken or overlooked early in life. However, there are several ways to confirm the condition:
Urine Testing: The gold standard in the diagnosis is the testing of urine samples for high levels of homogentisic acid via gas chromatography. In case of oxidation, which changes the color of urine to black, it is indicative of alkaptonuria.
Genetic Testing: Confirmatory genetic testing reveals mutations of the HGD gene to diagnose the condition conclusively.
Blood Tests: High levels of HGA in the blood can be used as further evidence.
Imaging Studies: X-rays and MRIs will expose cartilage and joint damage characteristic of alkaptonuria.
At present, there is no cure for alkaptonuria; however, various treatment approaches can reduce its symptoms and slow the disease's progress:
Nitisinone Therapy: Nitisinone is a drug that inhibits the production of HGA. It has been shown to reduce HGA levels and slow tissue damage. However, it needs to be taken under close medical supervision because of potential side effects.
Low-Protein Diet: Since HGA is a byproduct of protein metabolism, reducing protein intake—especially foods rich in tyrosine and phenylalanine—may help decrease HGA production.
Pain Management: OTC pain relievers and anti-inflammatory medications can be used to relieve joint pain and stiffness.
Physical Therapy: Exercise regularly, as it may improve mobility and strengthen muscles, thus reducing strain on affected joints.
Surgical Interventions: Most people with alkaptonuria develop severe osteoarthritis necessitating joint replacement in their old age. Also, some may require heart valve replacement surgery if cardiovascular complications develop.
Although alkaptonuria is not fatal, it severely affects the quality of life. The progressive deterioration of the joints and associated symptoms can make everyday activities difficult, requiring lifestyle changes and medical interventions. The disease may cause premature aging of the joints, requiring walking aids and mobility assistance earlier than expected.
Ongoing research will continue to work on improving the treatment options by focusing on gene therapy and alternative enzyme replacement therapies. However, because of its rarity, the clinical trials and research remain sparse.
As genetic research advances, more hope for better management and possible curative approaches for alkaptonuria exists. Scientists are searching extensively for enzyme replacement therapies and innovative drugs that can target the root cause of the disorder. Being aware and being diagnosed early helps individuals better their condition and ultimately have better long-term health outcomes.
Alkaptonuria is a striking example of how one gene mutation can have widespread effects on the body. Though still a rare and often misunderstood condition, growing awareness and advances in treatment are paving the way for better care. If you or a loved one suspect symptoms of alkaptonuria, it is essential to seek early diagnosis and medical guidance to manage the disease effectively and preserve quality of life.
Credit: AI
Sleep disturbances are among the most debilitating symptoms of Alzheimer’s disease. It often appears years before significant memory decline and other symptoms.
A new study from researchers at the University of Kentucky suggests that this sleep loss may not be permanent.
Instead, it could be driven by an immune response in the brain that may be reversible, sparking hope for new treatments.
Published in the journal Alzheimer’s & Dementia, the study found that brain immune cells called microglia, rather than amyloid plaques themselves, are the primary cause of sleep disruption in Alzheimer’s disease.
In mouse-based trials, researchers were able to restore more than two hours of sleep per day by temporarily removing these immune cells, without reducing amyloid plaques.
For years, scientists believed that sleep problems in Alzheimer’s were caused by the accumulation of amyloid plaques or the gradual death of brain cells. However, this study points in a different direction.
Researchers discovered that when amyloid plaques begin forming in the brain, they activate microglia, the brain’s resident immune cells.
Instead of protecting the brain, these cells cause inflammation that keeps brain circuits active, preventing sleep.
Using a drug called pexidartinib (PLX3397), the researchers temporarily depleted around 87% of microglia in Alzheimer’s mouse models.
This restored over two hours of daily sleep, particularly non-rapid eye movement (NREM) sleep, which is essential for tissue repair, memory strengthening, and clearing waste products from the brain.
Notably, the improvement occurred without changing amyloid plaque levels, suggesting that inflammation is manageable.
Lead researcher Dr. Shannon L. Macauley, associate professor of physiology at the University of Kentucky College of Medicine, said, “Basically, we showed that it is not the plaques themselves, or solely dysfunctional neurons, that cause sleep loss but actually microglia.
Microglia are immune cells that, when they respond to plaques, kick off this elaborate cascade of inflammation, as if the microglia are partying all night, and keeping the brain awake.”
She also highlighted why losing restorative sleep can accelerate disease progression.
“That restorative sleep is super important for physical repair, learning and memory and washing out the toxins of the day. When Alzheimer’s patients lose this stage, they lose their brain’s primary cleaning cycle, creating a feed-forward loop that may drive further damage,” she explained.
First author Dr. Nicholas J. Constantino said one of the biggest surprises was that sleep problems did not worsen as amyloid plaques increased.
“I expected that as plaque burden became more severe, sleep disruption would also worsen. The disruptions in sleep… did not worsen by 18 months, despite more than double the amount of plaque burden,” Constantino said.
Also read: What Is Type 3 Diabetes? Insulin Resistance In The Brain That Could Trigger Alzheimer’s
Poor sleep and Alzheimer’s create a vicious cycle. Sleep deprivation reduces the brain’s ability to clear amyloid-beta and tau proteins, which can accelerate disease progression, while worsening sleep.
Sleep disturbances affect up to half of people living with Alzheimer’s disease. The disease disrupts sleep due to various reasons:
Overactive microglia: As shown in the new study, immune cells become chronically activated by amyloid plaques, releasing inflammatory signals that keep the brain in a heightened state of activity.
Damage to sleep-regulating brain regions: Alzheimer’s progressively affects areas like the hypothalamus and brainstem that regulate the sleep-wake cycle.
Loss of NREM sleep: Due to lack of deep sleep, the brain’s ability to clear metabolic waste, including amyloid plagues weakens.
Circadian rhythm disruption: Degeneration of the brain’s internal clock leads to broken sleep and daytime drowsiness. This fuels confusion and agitation associated with the disease.
Credit: AI
Obesity has always been considered as one of the contributors to heart disease, diabetes, and stroke.
Now, growing research suggests that excess body fat, particularly in your 40s and 50s, may also accelerate brain aging and raise the risk of long-term cognitive decline.
Researchers say that obesity is not just linked with memory problems but also to significant changes in the brain structure.
Maintaining a healthy weight, especially during midlife, could help prevent memory problems and overall cognitive decline.
A recent study by researchers at the University of Georgia followed more than 8,200 adults aged 50 years and older for nearly 24 years.
The researchers found that individuals whose body mass index (BMI) increased over time experienced faster declines in cognitive performance than it would with normal aging. Excess body weight affected several aspects of cognition, including memory, planning, decision-making, problem-solving, emotional regulation, and concentration.
Lead author Dr. Claire Sexton (University of Georgia College of Public Health) said, "Maintaining a healthy body weight throughout adulthood may be an important strategy for preserving cognitive health later in life."
The study adds to the evidence that preventing weight gain throughout adulthood could become crucial for reducing dementia risk.
Also read: Grade-1 Fatty Liver: More Indians Are Developing It at Lower BMIs. What's Behind the Shift?
Obesity causes chronic low-grade inflammation, which can potentially damaging neurons essential for learning and memory.
The brain relies on glucose for energy. Insulin resistance, common in obesity, may impair how brain cells use glucose, affecting memory and thinking.
Obesity increases the risk of hypertension, atherosclerosis and vascular disease, reducing blood supply to brain tissue and potentially accelerating cognitive decline.
Experts believe visceral fat, the fat surrounding internal organs, may be more damaging than body weight alone. It produces inflammatory chemicals linked to brain changes and dementia risk.
Also read: Beyond Weight Loss: Scientists Discover How Exercise Can Help Reverse Muscle Aging
The latest findings are supported by several years of research. A large review published in Practical Neurology concluded that obesity is associated with smaller hippocampal volume, temporal lobe atrophy, mild cognitive impairment and increased Alzheimer's disease risk.
Some studies have suggested that obesity during midlife may nearly double the risk of developing Alzheimer's disease or dementia later in life.
Another review on obesity and aging reported that higher BMI is associated with poorer verbal memory, slower information processing and reduced executive function, particularly among older adults.
In January 2026, researchers also used genetic analyses to suggest that obesity and high blood pressure may directly contribute to dementia.
With a few lifestyle improvements, overweight and obese individuals can maintain a healthy BMI, reducing the risk of faster brain ageing and cognitive degradation. Experts recommend focusing on overall metabolic health rather than the number on the weighing scale alone.
Maintaining a healthy weight, regular exercise, controlling blood pressure, cholesterol and diabetes, following a Mediterranean diet, getting adequate sleep, remaining socially and mentally active can help maintain a healthy body weight.
Credit: AI
Living with someone who has hepatitis can be worrying. People tend to immediately wonder whether they are at risk simply by sharing meals, hugging, or living under the same roof.
Fortunately, the answer depends on the type of hepatitis, and in most cases, everyday household contact does not spread the virus.
Dr. Shalimar, Prof. Department of Gastroenterology, AIIMS explains, "Hepatitis means inflammation of the liver. There can be many causes, but viral hepatitis is one of the most common. There are different hepatitis viruses, including A, B, C, D, and E. Some cause acute illness, while others can lead to long-term liver damage, including cirrhosis and liver cancer."
Experts say misinformation surrounding hepatitis often leads to unnecessary fear and stigma, causing patients to feel isolated. Understanding how different hepatitis viruses spread can help families protect themselves without avoiding normal interactions.
Dr Nanda Kishore M, Gastroenterology, Athulya Geriatric Care Hospital, answers our question, "No, Hepatitis is not a communicable disease that spreads through everyday contact such as hugging, holding hands, coughing, or sneezing."
For most forms of hepatitis, the answer is no. However, hepatitis B is spread through contact with infected blood and certain body fluids. Household transmission is possible, but it generally occurs when infected blood enters another person's bloodstream.
Possible household risks include sharing:
Also read: Can Hepatitis Be Completely Cured? Understanding What Treatment Can Achieve
Dr. Kishore says that the mode of transmission largely depends on the type of hepatitis infected.
He says, "Hepatitis A and E are predominantly spread via means of contaminated food and water, while Hepatitis B and C are transmitted through infected blood and certain bodily fluids."
Hepatitis B is preventable by vaccine. Household members of someone with chronic hepatitis B are usually advised to get tested and vaccinated if they are not already immune.
Dr. Shalimar says, "For hepatitis B, current treatment controls the infection, and newer therapies under development offer hope for a functional cure in the future. Vaccination has dramatically reduced hepatitis B in many parts of the world. Expanding vaccination coverage remains one of the most effective ways to prevent the disease."
Living with a hepatitis infected individual is generally safe given that basic hygiene and recommended precautions are followed strictly. Understanding these facts helps reduce unnecessary fear and stigma associated with it.
Also read: Grade-1 Fatty Liver: More Indians Are Developing It at Lower BMIs. What's Behind the Shift?
Living with someone who has hepatitis does not mean you need to keep your distance. Instead, focus on practical precautions:
Dr. Ankur Jain, Associate Director & Unit Head, Gastroenterology, Hepatology & Endoscopy, Max Hospital, Dwarka, explains, "Hepatitis B and Hepatitis C continue to affect millions of people worldwide and remain major causes of liver cirrhosis and liver cancer. Individuals with a history of blood transfusions before routine screening, unsafe injections, or other risk factors should discuss screening with their physician.
He adds, "The liver has an extraordinary capacity to heal, but only if we identify problems early and address the underlying causes. Prevention, timely screening, and simple lifestyle modifications remain our most powerful tools in reducing the growing burden of liver disease in India."
© 2024 Bennett, Coleman & Company Limited