Autosomal dominant tubulointerstitial kidney disease-UMOD

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Autosomal dominant tubulointerstitial kidney disease-UMOD (ADTKD-UMOD) is part of a group of disorders (collectively called autosomal dominant tubulointerstitial kidney disease or ADTKD) that cause a slow loss of kidney function. In people with ADTKD-UMOD, the signs and symptoms of kidney disease often begin in adolescence or early adulthood. Over time, the kidneys become less able to filter fluids and waste products from the body. People with ADTKD-UMOD eventually develop kidney failure, which requires either dialysis to remove waste from the blood or a kidney transplant. The age at which people with ADTKD-UMOD develop kidney failure can vary, though the average age is approximately 45 years.

People with ADTKD-UMOD typically develop high levels of a waste product called uric acid in their blood. Normally, the kidneys transfer uric acid from the blood into urine, which then removes it from the body. People with ADTKD-UMOD are unable to remove uric acid from the blood effectively. In about 50 percent of people with ADTKD-UMOD, uric acid builds up in the joints and causes a form of arthritis called gout, typically in late adolescence or early adulthood. Gout is characterized by a sudden onset of severe joint pain and redness, often starting in the big toe. Untreated episodes of gout typically worsen over time.

Causes and biological mechanisms

From: MedlinePlus Genetics, National Library of Medicine

Variants (also called mutations) in the UMOD gene cause ADTKD-UMOD. This gene provides instructions for making the uromodulin protein. This protein is produced by the kidneys and then released from the body in urine. Uromodulin is the most common protein found in the urine of healthy individuals. It is thought to play a role in the transport of minerals such as sodium and potassium.

Most variants in the UMOD gene change single protein building blocks (amino acids) in the uromodulin protein. These variants typically alter the structure of the protein, though some variants have more severe effects on protein function than others. People with UMOD variants that have a greater effect on protein function generally have severe kidney disease, and these individuals experience signs and symptoms of kidney disease at a younger age. Typically, UMOD gene variants prevent kidney cells from releasing the uromodulin protein. The buildup of uromodulin may trigger the self-destruction (apoptosis) of cells in the kidneys, leading to kidney disease and eventual kidney failure.

Inheritance and family implications

From: MedlinePlus Genetics, National Library of Medicine

This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.

How common is it?

From: MedlinePlus Genetics, National Library of Medicine

ADTKD-UMOD is believed to account for fewer than 1 percent of all cases of kidney failure. Researchers aren't sure how common ADTKD-UMOD actually is, but it is considered to be one of the most common forms of kidney disease that is caused by changes in a single gene.

Understanding terms used in the source

These definitions explain medical words used above. A definition is not evidence that another condition is present, and it does not predict how a symptom will develop. Ask the clinician which terms apply to the actual examination or test result.

Healthy

No history of any serious disease, including the disease being investigated in the proband.

Which doctor should you see?

The suggested department for discussing Autosomal dominant tubulointerstitial kidney disease-UMOD is Nephrology, with a nephrologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• How is kidney function being assessed over time?
• Are any current medicines or supplements relevant to kidney safety?
• Is there an individual recommendation about fluids, diet or blood pressure?

Treatment discussions and follow-up

Where the source describes treatments, these are an overview of possible care, not a prescription for an individual. Ask which option applies to the confirmed diagnosis, what benefit is expected, what adverse effects to watch for and how progress will be assessed. Availability, approvals and local practice can differ from the country described in the source.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.