Liver Cysts & Hydatid Disease

The cause of simple cysts is not fully understood; they are thought to be present from birth and grow slowly over years. Hydatid disease spreads when a person swallows tiny parasite eggs that come from the stool of infected dogs. This can happen through contact with dogs, or through contaminated food, water or soil. Sheep and other livestock act as intermediate hosts. The eggs hatch in the gut, travel to the liver, and form slowly growing cysts that may take years to cause problems.

Simple liver cysts are common, especially with increasing age, and most people never know they have them. Hydatid disease occurs mainly in regions where people live closely with livestock, especially sheep, and dogs. It is less common in places with good animal-health controls. Several inherited conditions, such as polycystic liver disease, can also cause many cysts.

Contact with sheep, goats and camels and with working dogs, as well as home slaughter during celebrations, can be relevant for hydatid disease. Washing hands, keeping dogs away from offal, and disposing of animal organs safely are practical protections.

Ultrasound is the usual first test. A simple cyst looks like a smooth, thin-walled, clear fluid-filled sac. Hydatid cysts often have a thicker wall, internal divisions, or smaller "daughter" cysts inside, and they are further assessed by CT or MRI. A blood test for antibodies to the parasite can support the diagnosis, although it can be negative in some patients. Liver blood tests are usually normal in simple cysts. Needle sampling of a suspected hydatid cyst is avoided unless a specialist team decides it is needed.

For simple cysts there is usually nothing to change. For hydatid disease, prevention and avoiding trauma matter.

• Wash your hands with soap and water after touching dogs or livestock and before eating or preparing food.

• Do not feed dogs raw offal or organs from slaughtered animals; talk to a vet about regular deworming of working and farm dogs.

• Dispose of animal organs from home slaughter safely so dogs cannot eat them.

• If a large cyst is close to the surface, avoid contact sports and take care to protect the abdomen from blows.

• Household members of someone with hydatid disease do not catch it from the patient, but may share the same exposure; ask your doctor if they need testing.

No special diet treats liver cysts. Food hygiene helps to prevent hydatid infection.

• Wash raw vegetables, herbs and fruit thoroughly, especially if grown in soil that animals may have contaminated.

• Drink safe, treated water when travelling or when you are unsure of the source.

• Eat a balanced diet and keep a healthy weight; if you take anti-parasite medicines your doctor may advise taking them with a meal containing some fat.

Simple cysts do not need medicine. Hydatid cysts may be treated with anti-parasite medicines, chosen and monitored by your doctor.

• Albendazole is the usual anti-parasite medicine; the dose and duration are decided by the doctor.

• It is often given before and after a procedure or surgery to lower the risk of the cyst returning or spreading.

• Blood tests of liver function and blood counts are needed during treatment, as the medicine can affect them.

• Do not use this medicine in pregnancy or when planning pregnancy without discussing it with your doctor.

Procedures are used for cysts that cause symptoms, are growing, or are hydatid cysts that need treatment. The choice depends on the type of cyst and is made by a specialist team.

• Observation with ultrasound is appropriate for small cysts without symptoms and for inactive hydatid cysts.

• Keyhole (laparoscopic) surgery can remove part of the wall of a large symptomatic simple cyst.

• Needle drainage with a sclerosing agent is sometimes used for simple cysts.

• For hydatid cysts, a radiology-guided procedure or surgery done with special care to avoid spillage may be advised.

• If a cyst has opened into the bile ducts, an ERCP (an endoscopic bile duct procedure) may be needed.

For hydatid cysts, treatment is now tailored to the stage of the cyst seen on imaging. Options include observation of inactive cysts, medicines against the parasite, a minimally invasive procedure (known as PAIR) in selected cysts, and surgery. For simple cysts, treatment of large symptomatic cysts with keyhole surgery or drainage with a sclerosing agent are well-established options.

Simple cysts that cause no symptoms generally need no treatment and no follow-up beyond what your doctor advises. Symptomatic ones can be treated effectively. Hydatid disease can be cured or controlled in most patients with the right combination of medicine and procedure, but it needs follow-up with scans for a number of years because cysts can come back.

• Is my cyst a simple cyst or a hydatid cyst?

• Does it need treatment or only follow-up scans?

• If it is hydatid, which treatment is best for its stage?

• Could my family or I have other cysts in the lungs or elsewhere?

• How often will I need scans?

This guide comes from the Saudi Gastroenterology Association (SGA) patient library, prepared by the Approved for publication by SGA; individual clinician review is ongoing. Last reviewed: 2026-04-24. It is for education and does not replace your doctor's advice.