It was only recently that the name “autosomal dominant tubulointerstitial kidney disease” (ADTKD) was developed to refer to a group of rare inherited kidney diseases. These conditions are characterised by high levels of creatinine and a chronic renal illness that advances slowly. Symptoms of ADTKD may go undiagnosed until the creatinine level is raised because to the autosomal dominant inheritance of the disease. 

Dialysis or a kidney transplant may be necessary between the fourth and seventh decades of life, depending on the kind of ADTKD. ADTKD comes in a variety of forms, the two most prevalent of which are ADTKD-UMOD and ADTKD-REN. In a small percentage of ADTKD patients, UMOD gene mutations can be found using exome sequencing. REN mutations are also linked to ADTKD, a condition marked by congenital anaemia, which is another phenotype of ADTKD. Finally, further mutations, such those in the HNF1B gene, have been connected to ADTKD.

Causes

Mutations in a few genes lead to ADTKD. Certain genetic issues are inherited (transmitted within families) in an autosomal dominant manner. It follows that just one parent must carry the faulty gene for the disease to be inherited. The disease frequently affects a large number of family members.

The kidney tubules are harmed as the illness worsens in all types of ADTKD. These kidney structures are responsible for filtering and returning the majority of water in the blood.

The different forms of ADTKD are associated with abnormal genes, including:

– UMOD gene: Causes ADTKD-UMOD, also known as uromodulin kidney disease.

– MUC1 gene: Causes ADTKD-MUC1, or mucin-1 kidney disease.

– REN gene: Causes ADTKD-REN, or familial juvenile hyperuricemic nephropathy type 2 (FJHN2).

– HNF1B gene: Causes ADTKD-HNF1B, or maturity-onset diabetes mellitus of the young type 5 (MODY5).

When the cause of ADTKD is unknown or a genetic test has not been conducted, it is referred to as ADTKD-NOS.

Symptoms

When the kidneys lose their ability to concentrate urine and retain salt, it results in increased urine production and excessive thirst in individuals. Children one year of age or older get the first signs of nephronophthisis. Children may have weaker bones and their growth is hindered. Individuals who have nephronophthisis may also have intellectual disabilities, ocular issues, or liver disorders (mental retardation). Chronic renal disease can develop later in infancy and lead to anaemia, hypertension, nausea, and weakness.

Symptoms of autosomal dominant tubulointerstitial kidney disease typically manifest during adolescence or early adulthood. In comparison to nephronophthisis, excessive thirst and abnormal urine production are not as severe. There may be high blood pressure in people. Not impacted are any other organs. Most people with chronic renal disease are between the ages of 30 and 70. Gout can appear in some persons.

Diagnosis

The diagnosis of ADTKD is made using a combination of physical examination, laboratory tests, imaging scans, and genetic testing. Proteinuria, edoema, and elevated blood pressure are a few physical examination findings that could indicate renal impairment. A complete blood count, urinalysis, and kidney function tests are examples of laboratory tests that might be performed. The size and structure of the kidneys can be determined using imaging tests like an ultrasound, CT scan, or an MRI. The precise mutation causing the condition can be found through genetic testing.

Treatment 

Slowing the disease’s course and treating symptoms are the goals of treatment for ADTKD. High blood pressure can be managed and fluid retention can be decreased with the help of medications including ACE inhibitors, angiotensin receptor blockers, and diuretics. To lessen proteinuria and hematuria, other drugs may be utilised. Transplantation of the kidneys may be required in specific circumstances.

-Controlling high blood pressure

-Managing anemia

-Maintaining appropriate levels of sodium and uric acid in blood

As part of treatment, controlling anaemia, excessive blood pressure, and salt and uric acid levels in the body are also important. For kids whose growth has slowed down, growth hormone or nutritional supplements may be required. Allopurinol may be given when gout begins to manifest. To compensate for the excessive sodium excretion and the production of large volumes of diluted urine, particularly in nephronophthisis, a substantial daily intake of fluids and salt (sodium) is needed. When end-stage renal failure occurs, chronic kidney disease follows, which may necessitate dialysis or a kidney transplant.

Prognosis

A series of complicated disorders that affect the kidney’s tubules collectively are known as autosomal dominant tubulointerstitial kidney disease (ADTKD). The outlook with ADTKD differs from patient to patient. Early detection of the condition usually leads to a more favorable prognosis. By identifying and treating the disease promptly, its progression can be slowed down, and the individual’s quality of life can be improved. [1] The condition is typically identified by bland urine sediment, tubulointerstitial nephropathy, and increasing renal failure. [2] As a result, dialysis or a kidney transplant may be necessary if the condition progresses to end-stage renal failure. [3] Those who have MUC1 mutation-related disease have a worse prognosis than people who have sickness for unknown genetic reasons.

Preventions

The most effective approach to prevent autosomal dominant tubulointerstitial kidney disease (ADTKD) is by maintaining a healthy lifestyle. This involves engaging in regular exercise, following a well-balanced diet, and avoiding habits that can impose undue strain on the kidneys, such as excessive alcohol consumption or smoking. Keep an eye on your uric acid levels because ADTKD-UMOD is associated with higher-than-normal amounts of uric acid. Allopurinol or febuxostat are suggested as the top medications for treating gout and hyperuricemia in ADTKD-UMOD patients. Additionally, it’s essential to routinely evaluate renal function in order to spot any reductions or irregularities as soon as feasible. But if the condition is detected soon and properly treated, the prognosis can be improved.