Kidney tubulopathy-dilated cardiomyopathy syndrome

What it is

From: Orphanet

A rare genetic disease characterized by the combination of (i) a salt-losing renal tubulopathy with hypomagnesemia and hypokalemic metabolic alkalosis and (ii) dilated cardiomyopathy.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Dilated cardiomyopathy · Very frequent (99-80%)

Dilated cardiomyopathy (DCM) is defined by the presence of left ventricular dilatation and left ventricular systolic dysfunction in the absence of abnormal loading conditions (hypertension, valve disease) or coronary artery disease sufficient to cause global systolic impairment. Right ventricular dilation and dysfunction may be present but are not necessary for the diagnosis.

Hypermagnesiuria · Very frequent (99-80%)

An increased concentration of magnesium the urine.

Hypocalcemia · Very frequent (99-80%)

The concentration of calcium in the blood circulation is below the lower limit of normal.

Hypomagnesemia · Very frequent (99-80%)

The concentration of magnesium in the blood circulation is below the lower limit of normal.

Hypercalciuria · Very frequent (99-80%)

Hypokalemic metabolic alkalosis · Very frequent (99-80%)

Abnormality of renal resorption · Frequent (79-30%)

An abnormality of renal absorption.

Arthralgia · Frequent (79-30%)

Joint pain.

Congestive heart failure · Frequent (79-30%)

The presence of an abnormality of cardiac function that is responsible for the failure of the heart to pump blood at a rate that is commensurate with the needs of the tissues or a state in which abnormally elevated filling pressures are required for the heart to do so. Heart failure is frequently related to a defect in myocardial contraction.

Hepatic calcification · Frequent (79-30%)

The presence of abnormal calcium deposition in the liver.

Hyperkinetic movements · Frequent (79-30%)

Motor hyperactivity with excessive movement of muscles of the body as a whole.

Hyperprostaglandinuria · Frequent (79-30%)

An increased concentration of prostaglandin in the urine.

Hypocalcemic tetany · Frequent (79-30%)

Hyperexcitability of the neuromuscular system related to abnormally low level of calcium in the blood, resulting in carpopedal or generalized spasms.

Increased circulating aldosterone concentration · Frequent (79-30%)

Overproduction of the mineralocorticoid aldosterone by the adrenal cortex.

Other findings in the same source

From: Orphanet

Additional reported features include Nephrocalcinosis (Frequent (79-30%)); Pericardial effusion (Frequent (79-30%)); Pulmonary edema (Frequent (79-30%)); Sudden cardiac death (Frequent (79-30%)); Myoclonic spasms (Frequent (79-30%)); Bilateral tonic-clonic seizure (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Adolescent; Adult; Antenatal; Childhood; Infancy

Inheritance in the source

From: Orphanet

Autosomal dominant

Frequency and the population described

From: Orphanet

Reported case(s): 37.0; Worldwide. This is a published case count, not prevalence. Point prevalence: <1 / 1 000 000; Worldwide; Class only.

Understanding the inheritance label

From: MedlinePlus Genetics

An autosomal dominant pattern means that one altered copy of a relevant gene can be sufficient for the condition. Some affected people inherit the change; others have a new change without an affected parent. The precise finding, family history and condition determine what this means for relatives.

Which doctor should you see?

The suggested department for discussing Kidney tubulopathy-dilated cardiomyopathy syndrome 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

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Kidney tubulopathy-dilated cardiomyopathy syndrome. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

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.