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A 40-year-old resident of Hyderabad became anxious when he discovered he had a kidney cyst after undergoing an ultrasound scan during an annual health checkup. Karthik (name changed) immediately approached Dr Mamidi Pranith Ram, a nephrologist at Yashoda Hospitals, Hyderabad, to address the concern. “Karthik had a simple cyst in his kidney, which was benign. Thus, I had to reassure him that he does not need any treatment for his cyst,” mentions Dr Ram.
Cysts are fluid-filled sacs that can form in the skin or any other internal organ of the body. One such organ where cysts can lead to potential complications is the kidney. Happiest Health spoke to experts who explain the different kinds of kidney cysts and when one should be concerned about them.
How are kidney cysts formed?
According to the National Institute of Health, while there is no known cause of kidney cysts, their likelihood increases with age, which is more prevalent in men than in women.
“Cysts might contain urine, water or other bodily fluids,” says Dr Rushi Deshpande, nephrologist, HN Reliance Hospital, Mumbai.
Speaking about the prevalence of kidney cysts, Dr Ram says, “About 50 per cent of the people over the age of fifty or sixty are likely to have a simple cyst, which is benign.”
Types of kidney cysts
Dr Ram lists the different types of kidney cysts, which include:
♦ Simple cysts: These cysts might be single or multiple. They are benign, asymptomatic and occur with age.
♦ Complicated cysts: This form of cyst can be of two kinds:
- Congenital cysts: They occur due to genetic abnormalities and cause conditions like polycystic kidney disease, which happens due to the presence of multiple cysts. People with congenital cysts are most likely to suffer from renal failure over time.
- Acquired cysts: They contain a cavity filled with fluid or semisolid debris. People living with chronic kidney disease, especially those on dialysis, are prone to developing such cysts, which might be malignant.
To differentiate between simple and complicated cysts, Dr Deshpande recommends an ultrasound and a CT scan. “In certain cases, an MRI scan might also be required,” he adds.
In addition, Dr Ram says that autosomal dominant polycystic kidney disease (ADPKD) — an inherited disorder where clusters of cysts develop in the kidneys — is commonly seen during adulthood. This can be of two types: ADPKD type 1, where people can develop renal failure around the age of 60–65 years and ADPKD type 2, where the likelihood of developing renal failure is around the age of 75–80 years.
Can kidney cysts be cancerous?
“Most cysts are simple, which means that the chances of them being cancerous or infectious are rare,” says Dr Deshpande.
However, complicated cysts might be cancerous, which can worsen and spread over time. “There are ways to grade complicated cysts with ultrasound imaging using an important classification system called the Bosniak scale. One should go for a CT scan only if a complicated cyst is detected in an ultrasound scan,” he adds.
Symptoms of kidney cysts
Kidney cysts do not show any symptoms unless they get infected or start affecting kidney function, says Dr Deshpande.
However, Dr Ram explains that complicated cysts can affect kidney functioning and present with symptoms of polycystic kidney disease, which include:
- Abdominal pain or discomfort
- Heaviness in the abdomen
- Acute pain in case of cyst rupture
- Hematuria (blood in the urine)
- Kidney stones, causing acute abdominal pain
“People who visit the ER [emergency room] with complicated cysts may present with breathlessness and blood in the urine. In such cases, tests usually reveal that the cyst has turned malignant,” says Dr Ram.
Treatment of kidney cysts
Complicated cysts (which include ADPKD) can lead to renal failure over time. “Treatment options in such cases include dialysis and kidney transplant,” says Dr Ram, further advising people with cysts to quit smoking, as it increases the risk of malignancy over time.
“If you don’t have a family history of cystic kidney conditions or kidney failure, you don’t need to be concerned about cysts,” reassures Dr Deshpande.
In case a cyst is detected in the ultrasound, it is important to go for a yearly checkup to ensure that it is not increasing in mass and size or turning into a complicated cyst. “Although chances of that happening are quite rare, it is recommended to keep the simple cyst in check,” advises Dr Deshpande.
Takeaways
- Cysts are fluid-filled sacs that consist of water, urine and other bodily fluids. The likelihood of developing kidney cysts increases with age.
- Cysts can broadly be classified as simple cysts, which are benign and complicated cysts, which might be malignant.
- If a cyst is detected in the ultrasound, a yearly checkup is vital to make sure it doesn’t increase in size or mass, which in turn can cause complications over time.
