What Is Alkaptonuria? The Rare Disease That Turns Your Pee Black – Here’s Why

Updated Feb 7, 2025 | 08:00 AM IST

SummaryAlkaptonuria is a rare genetic disorder that causes black urine due to homogentisic acid buildup, leading to joint pain, cartilage damage, and skin discoloration. It has no cure but can be managed.
What Is Alkaptonuria? The Rare Disease That Turns Your Pee Black – Here’s Why

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.

Symptoms of Alkaptonuria

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.

How is Alkaptonuria Diagnosed?

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.

Management of Alkaptonuria: Is There A Cure?

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.

Life with Alkaptonuria

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.

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A La Carte Knee Replacement: A Personalized Approach To Joint Care

Updated Apr 29, 2026 | 07:04 AM IST

SummaryIn knee replacement surgery, à la carte technique means replacing only the damaged portion of the joint, rather than the entire knee. It helps preserve the natural structure of the knee while effectively treating only the damaged portion.
A La Carte Knee Replacement: A Personalized Approach To Joint Care

Credit: iStock

Knee replacement surgery has witnessed remarkable advancements over the past few years. Traditionally, total knee replacement was performed as a uniform procedure ("one procedure fits all"), where the entire knee joint was replaced regardless of the extent or location of damage.

However, with the evolution of modern orthopedics, the focus has shifted towards precision and personalized treatment. In this direction, an A La Carte or Modular approach towards patients who need knee Replacement has emerged, which customizes or personalizes the surgery according to the patient’s specific condition.

Understanding The “à la carte” Concept

The term “à la carte” refers to selecting individual items from a menu. In knee replacement surgery, it means replacing only the damaged portion of the joint instead of the entire knee.

The knee is anatomically divided into three compartments:

  • Medial compartment (inner side)
  • Lateral compartment (outer side)
  • Patellofemoral compartment (front portion involving the kneecap)

In many patients suffering from osteoarthritis, the disease affects only one or two of these compartments—most commonly the medial compartment. In such cases, replacing the entire knee may not be necessary. Modular implants allow surgeons to selectively treat the affected area while preserving healthy bone and ligaments.

The à la carte technique helps preserve the natural structure of the knee while effectively treating only the damaged portion, resulting in better and more natural functional outcomes for patients.

However, this approach is not suitable for all patients. It is generally not recommended in inflammatory conditions such as rheumatoid arthritis.

How It Differs From Total Knee Replacement

In Total Knee Replacement (TKR), all three compartments of the knee are replaced, making it an effective solution for advanced and widespread arthritis.

In contrast, Modular Knee Replacement offers a more targeted approach:

  • Replacement of a single compartment (Partial Knee Replacement)
  • Replacement of two compartments (e.g., medial + patellofemoral)

This selective treatment helps maintain the knee’s natural structure and function.

Advantages Of The Modular Approach

For carefully selected patients, this technique offers several important benefits:

  • More natural knee function: Preservation of ligaments and bone provides a more natural feel.
  • Faster recovery: Less invasive surgery leads to quicker rehabilitation.
  • Reduced pain and blood loss: Minimal surgical trauma results in less discomfort.
  • Improved mobility: Patients often achieve a better range of motion.
  • Enhanced lifestyle comfort: Activities like sitting cross-legged or squatting may be easier and can be done unrestricted compared to total knee replacement.

Who Is the Ideal Candidate?

Not every patient is suitable for this procedure. Proper patient selection is one of the most critical factors in ensuring the success of this procedure. Ideal candidates typically include people:

  • Having arthritis limited to one or two compartments
  • Having stable knee ligaments
  • Who do not have a severe deformity in the knee
A thorough clinical evaluation, along with imaging such as X-rays or sometimes an MRI, is essential to determine the most appropriate treatment plan.

Long-Term Outcomes

When performed in the right patient, modular knee replacement delivers excellent long-term outcomes (90 to 95 per cent survivorship for 15 years). Its success largely depends on accurate patient selection and flawless surgical expertise.

In some cases, if arthritis progresses in the remaining compartments over time, conversion to total knee replacement can still be done. However, this is relatively uncommon when proper indications are followed.

Role Of Robotic Technology

Robotic-assisted surgery has further enhanced the precision of this technique. It enables:

  • Millimeter-level accuracy
  • Precise implant positioning
  • Restoration of patient-specific knee alignment
This not only improves surgical outcomes but also supports faster recovery and long-term durability.

Conclusion

Ala Carte or Modular Knee Replacement represents a significant shift toward personalized orthopaedic care. Instead of a "one-size-fits-all " approach, surgeons can now tailor treatment based on the patient’s anatomy and disease pattern.

For many patients, this means less invasive surgery, faster recovery, improved function, and a more natural-feeling knee. Individuals experiencing persistent knee pain are advised to consult an orthopaedic specialist early to determine the most appropriate treatment option.

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Not Just Lungs: PM2.5 Driving Breast, Liver Cancer Mortality, Says Global Study

Updated Apr 28, 2026 | 10:30 PM IST

SummaryFor every 10 micrograms per cubic meter (µg/m³) increase in PM₂.₅ exposure, the overall risk of cancers increases by more than 11 per cent. At the same time, the risk of death also increases by more than 12 per cent for every 10 µg/m³ increase in PM₂.₅ exposure.
Not Just Lungs: PM2.5 Driving Breast, Liver Cancer Mortality, Says Global Study

Credit: Canva

Beyond lung cancers, air pollution fine particulate matter (PM2.5) is increasing mortality for breast as well as liver cancers, according to a global study led by the Union for International Cancer Control (UICC), including researchers from the Indian Council of Medical Research (ICMR).

The important study showed that long-term exposure to PM2.5 increases the overall risk of developing cancer and the chances of dying from it compared with those living in cleaner environments.

For every 10 micrograms per cubic meter (µg/m³) increase in PM2.5 exposure, the overall risk of cancers increases by more than 11 per cent. At the same time, the risk of death also increases by more than 12 per cent for every 10 µg/m³ increase in PM2.5 exposure.

The researchers argued that while other common risk factors like tobacco and alcohol are being targeted with notable progress, air pollution is silently eroding the gains being made.

“We have made huge strides in reducing deaths from cancer, but polluted air is silently undermining that progress. It is a risk people cannot opt out of, and one that disproportionately affects women, children, and people living in poverty,” Cary Adams, CEO, UICC.

“The cancer community continues to make progress in addressing other major risk factors, including tobacco use, alcohol consumption, and viral, bacterial, or parasitic infections such as HPV and HBV that cause cervical and liver cancers. It is increasingly clear that air pollution must also be recognized as a major and preventable factor that increases the risk of developing cancer and of dying from the disease,” added Dr Elisabete Weiderpass, Director, IARC.

Risks of PM2.5: Beyond Lung Cancer

The study, based on data from 42 meta-analyses and systematic reviews published between 2019 and 2024, showed significantly strong associations for liver, colorectal, and breast cancers.

As per recent data from the International Agency for Research on Cancer (IARC), PM₂.₅ exposure contributes to 434,000 lung cancers per year, accounting for more than a quarter of preventable lung cancers in women and nearly one in six in men.

In addition to lung cancer risk, the study noted that the rising levels of PM2.5 are associated with

  • a 32 per cent higher incidence of liver cancer
  • an 18 per cent increase in the odds of developing colorectal cancer.
Further, mortality risks also rise as pollution levels increase, with

  • a 12 per cent higher overall risk of dying from cancer,
  • a 20 per cent higher risk of death from breast cancer,
  • a 14 per cent from liver cancer,
  • a 12 per cent from lung cancer.

Who Is At A Higher Risk

Not Just Lungs: PM2.5 Driving Breast, Liver Cancer Mortality, Says Global Study

According to the researchers, people living in low- and middle-income countries bear the greatest overall burden. These countries frequently lack the resources to reduce pollution at source or to provide timely access to cancer prevention, diagnosis, and treatment.

The challenge is compounded by the projected rise in global cancer cases, expected to increase from 20 million in 2022 to 35 million by 2050. People at risk include:

  • Women and children, particularly in settings where solid fuels are used for cooking and heating.
  • Women exposed to household air pollution face a 69 per cent higher risk of lung cancer, alongside increased risks of cervical cancer.
  • Outdoor workers and communities living near industrial facilities are also at heightened risk, with exposure often concentrated in economically deprived areas.

What Actions Are Required?

The researchers underscored that the evidence presented in the report is already sufficient to justify decisive action to reduce exposure to polluted air. They called upon policymakers to make required changes across energy, transport, industry, and urban planning to reduce the risk of cancer from air pollution.

The study urged the need for properly implementing effective interventions that are well-established. These include:

  • Stronger emissions standards and enforcing the WHO air quality Standards
  • A transition to clean energy and clean cooking
  • Improved urban design by investing more in green infrastructure
  • Expanded air-quality monitoring in High-Risk Areas
  • Update cancer control plans.

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Overhydration: What Happens When Kidney Patients Drink Too Much Water In Summer

Updated Apr 29, 2026 | 01:03 AM IST

SummaryMany people overhydrate during summer thinking that it is the key to being healthier. However, overhydration does more harm than good to kidney disease patients.
Overhydration

Overhydration can cause electrolyte imbalance in kidney disease patients. (Photo credit: AI generated)

During the summer, it is important to stay hydrated, but for kidney patients, excessive intake of fluids is just as dangerous as not drinking enough. Most people are encouraged to drink extra fluids during hot weather; however, patients with chronic kidney disease (CKD) and those on dialysis must exercise greater control over their daily hydration and fluid intake because their bodies cannot effectively excrete excess fluids, leading to potential complications.

What is overhydration?

Dr Anupam Roy, Additional Director – Nephrology and Kidney Transplant at Aakash Healthcare Multi-Specialty Hospital, Dwarka, said, “Overhydration occurs when the body retains more fluid than it is able to eliminate. For kidney patients, overhydration typically leads to fluid overload as a result of excessive fluid accumulation in the body. Early signs of fluid overload may include swelling in the feet, ankles, and/or face. If not treated, fluid may continue to build up and cause the lungs to fill with fluid, resulting in shortness of breath and difficulty lying down. If left untreated, gaseous exchange in the lungs will be impaired, and the patient will require immediate medical treatment for pulmonary oedema (a life-threatening complication).”

What happens when you are overhydrated?

The effect of excess fluid on the heart and blood pressure is considered a significant concern. Excess fluid results in additional strain on the cardiovascular system, leading to high blood pressure. This extra workload may also increase the risk of serious complications (e.g., heart failure) for individuals who already have hypertension or heart disease. Dialysis patients are at particular risk of developing complications since they rely on regularly scheduled treatments to remove excess fluid. Excessive fluid consumption between dialysis sessions may complicate and increase the discomfort associated with removing excess fluid during dialysis.

How does overhydration affect kidney disease patients?

Overhydration may also cause an imbalance in electrolytes, such as sodium. Consuming a large amount of water without adequate intake of electrolytes could dilute sodium in the bloodstream, resulting in hyponatraemia. Symptoms of hyponatremia vary from mild (nausea and headaches) to severe (confusion, seizures, and, in extreme cases, coma). This condition can potentially be life-threatening for kidney disease patients, who often have difficulty maintaining an optimal balance of electrolytes.

Many people forget that they can obtain fluids from certain foods and drinks, such as soup, yogurt, watermelon, and tea or juice. In the summertime, people tend to consume these types of foods and drinks more often, which can cause them to exceed the recommended daily fluid intake. Many also believe that drinking extra water will flush toxins out of their system; however, when the kidneys are not functioning properly, excess fluids can be difficult to remove from the body.

How much water should kidney patients drink?

Dr Roy said that proper hydration for someone with kidney disease needs to be planned carefully. The amount of fluid a person can consume depends on their stage of kidney disease, urine output, and whether they are on dialysis. Some simple strategies can help maintain proper hydration: use small cups for drinks, consume fluids throughout the day rather than all at once, avoid foods high in salt (as these increase thirst), and track daily fluid intake.

The main reason for drinking fluids is to ensure the right amount is consumed; therefore, the most important aspect of hydration is maintaining balance. Maintaining this balance can help prevent complications and allow individuals to remain as healthy as possible. When kidney patients understand their hydration needs and receive proper guidance during the summer, they can avoid causing further harm by placing additional strain on their bodies.

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