Q: My 30-year-old daughter recently underwent an ultrasound. I am not quite sure if she had it because she was having stomach pains or whether it was just routine. The check discovered that she has some cysts on her kidneys. Is this serious? Should I be concerned? She did suffer from toxoplasmosis a few years ago. Can this lead to cysts on the kidneys?
A: Cysts in the kidney vary in size. They can be so small that they can only be seen under the microscope or they can be as large as ping pong balls. They are round with thin walls and filled with fluid. They occur when a filter tube in the kidney expands to an abnormal size, perhaps due to a blockage. These cysts are not cancerous.
Read Also

Food can play a flavourful role in fun summer activities
Recipes – popsicles are made with lactose-free milk and yogurt so are perfect for those who can’t tolerate milk, while everyoneelse will also enjoy them
In your daughters’ case, the most likely scenario is that this is a normal occurrence. It can be normal to have up to five cysts in one kidney.
Medullary sponge kidney leads to small cysts in both kidneys. These are formed as the result of infections or small renal stones. These do not usually cause any lasting or major damage to the kidney, and no treatment is needed unless the infection has not cleared up or the stones are large or numerous enough to cause pain.
Infantile or recessive polycystic kidney disease results in hundreds of cysts in each kidney, but it occurs in infancy or early childhood. Adult polycystic disease also causes hundreds of cysts. However, unless there are more than 30 cysts in each kidney, there is little chance of kidney damage, let alone renal failure. There are about a million tubes in each kidney, so a person can easily spare 30.
May not be symptoms
Polycystic kidneys are inherited in a dominant way, so if one parent carried the gene, each child has a 50 percent chance of developing the disease. It affects one in 1,000 North Americans. There could be more because often there are no symptoms. Other symptoms include upper back pain, anemia and high blood pressure.
Polycystic kidney disease has also been associated with cysts in the liver, pancreas or testes, and sometimes with diverticuli in the large intestine or colon. This illness progresses slowly.
I expect the doctors will first do some simple tests such as urinalysis, blood count and check her blood pressure, and will only refer her to a specialist if there are abnormal results.
To accurately determine the number of cysts your daughter has, she may need an intravenous pyelogram. This is a type of kidney X-ray where a dye is first injected so the kidneys show up better.
I am not sure whether toxoplas-mosis can lead to cyst formation. I know this can happen in wild animals that act as hosts for this microscopic parasite, but humans are generally considered an end host because they do not pass the disease on to one another.
However, an unborn child can be affected if the mother has toxoplasmosis. This is a disease that comes from cats, which is why women in the first few months of pregnancy should have nothing to do with cleaning the kitty litter.
Clare Rowson is a medical doctor with a practice near Belleville, Ont. Her columns are intended for general information only. Individuals are encouraged to also seek the advice of their own doctor regarding medical questions and treatments.