Abdominal cysts may represent a variety of different abnormalities.  Most are diagnosed by prenatal ultrasound, but other come to clinical attention later.

Mesenteric Cysts

Mesenteric cysts are frequently located in the mesentery of the small intestine.  They can be asymptomatic and are found more in males than females.  They can vary in size and children commonly present with abdominal pain, vomiting and/or a mass in the abdomen.  They are often diagnosed by abdominal CT scan or ultrasound.  The cysts can cause the bowel to twist or volvulize and that is probably the source of the pain and vomiting.  The cysts can become acutely infected so some patients may have a fever or elevated white blood cell count.  Most will require a partial small bowel resection and this can be performed laparoscopically.

Intestinal Duplication Cysts

Intestinal duplication cysts or enteric cysts can be located anywhere in the gastrointestinal tract from the base of the tongue to the rectum.  Seventy-five percent are located in the abdomen and the rest are located in the thorax with a small number crossing the diaphragm.  Most do not communicate with the lumen of the bowel but 25% are tubular duplications that do communicate with the bowel.  Some cysts have ectopic tissue in the lining, including gastric mucosa, and these can cause ulceration and bleeding.

Most patients develop symptoms in the first two years of life, commonly with partial intestinal obstruction.  Patients can have abdominal pain or difficulty swallowing or breathing if the cyst is located in the thorax.  Diagnosis is by ultrasound or CT scan.  Ten percent of patients have more than one cyst so imaging of two body cavities may be indicated.

Treatment involves resection if symptomatic.  Laparoscopic and thoracoscopic approaches can be helpful.

Renal Cysts

Simple renal cysts are usually benign are are identified on ultrasound or CT scan.  They should be differentiated from hydronephrosis and from cysts that could be in adjacent structures such as the liver or adrenal gland.

Multicystic dysplasia can commonly be diagnosed prenatally and is characterized by multiple cysts of different sizes and no identifiable renal parenchyma or tissue.  The other kidney is usually functioning fine.  Complications include hypertension or infection and treatment can include resection if needed.

Polycystic kidney disease involves both kidneys and can be diagnosed prenatally.  It is characterized by microscopic cysts.  It can be associated with pulmonary hypoplasia and oligohydramnios.  Renal insufficiency can be present in these newborns or it can appear later in life.

Splenic Cysts

Splenic cysts or pseudocysts are considered to arise from previous injury or trauma to the spleen.  Patients present with abdominal pain and may have a mass in the left upper quadrant.  CT scan or ultrasound can be used for diagnosis.  Treatment includes removal of the cyst wall or partial splenectomy and a laparoscopic approach is helpful.  Complications include recurrent cyst formation.