Are fluid filled cavities in the liver that are asymptomatic and usually found incidentally on abdominal imaging. Larger cysts are more commonly associated with symptoms and complications.
Differential diagnosis for all liver cysts
Liver abscess
Benign tumors
Malignant tumors
Regenerative nodules
Cholelithiasis
GERD
Peptic ulcer disease,
Gastric dysmotility
Hemangioma, and/or hamartoma.
Classification
Simple cysts
Hydatid cysts
Congenital polycystic liver
Biloma
Simple cysts
Are congenital in origin
Risk factors
Age more than 50 years
More common in females
Signs and symptoms
Small cysts are asymptomatic but larger ones may present with dull abdominal pain in the right upper quadrant, anorexia and bloating.
Side note Significantly large cysts may even be palpable on abdominal examination
Investigations
An ultrasound is performed which shows an anechoic round lesion whilst CT shows a well demarcated lesion.
Management
If symptoms are present laparoscopic surgery is done.
Complications
Larger cysts can
Compress the biliary tree
Rupture and cause infection
Hydatid cysts
Fluid filled cavities caused by tapeworm infection of echinococcus genus that are transmitted via faecal contaminated food, water or soil. Most commonly seen in farming or rural communities.
Remember They can even be transferred from the fur of dogs, cats, foxes!
The eggs travel to body organs through the bloodstream after penetrating the intestinal wall -> Cyst formation
Mainly two types
Cystic echinococcosis
Infection by E. granulosus
Usually present as a single liver cyst
Signs and symptoms
Echinococcal cysts can be asymptomatic or cause increased temperature ,bloody sputum, and pruritus.
On GPE hepatomegaly and right upper quadrant tenderness is recorded. Patients also complain of non-specific symptoms such as malaise ,nausea and vomiting.
Remember Hydatid cysts are known to rupture an cause anaphylactic shock which can be fatal!
Investigations
Ultrasound shows anechoic, smooth, well demarcated cyst. When present with daughter cysts, ultrasound can detect characteristic internal septations.
Eggshell calcifications may be seen in cyst walls.
CT scan
Echinococcus ELISA (serology)
Eosinophilia, low wbcs and low platelets
Alveolar echinococcosis
Infection by E. multilocularis that behaves like hepatocellular carcinoma destroying surrounding structures.
Signs and symptoms
Hepatic cyst causing hepatomegaly and right upper quadrant pain as well as the non specific symptoms.
Cyst invades and destroys liver parenchyma causing
Portal hypertension
Liver cirrhosis
Cholangitis
Jaundice
Budd-chiari syndrome
RememberE. multilocularis has potential of malignancy thus higher mortality thanE. granulosus
Investigations
Ultrasound Liver - Irregular lesions with poor margins with central necrosis as well as cyst wall calcifications
CT scan
Echinococcus ELISA (serology)
Eosinophilia, low wbcs and low platelets
Management
Asymptomatic simple hepatics cysts do not require any treatment but cysts larger than 4cm are monitored.
Cysts less than 5 cm are treated with antihelminthic agents such as albendazole or mebendazole.
The three operations performed that remove the cyst or reduce its size are
Percutaneous aspiration
Done in combination with albendazole
Cysts more than 5cm
Laparoscopic deroofing
If aspiration not successful or viable
Much lower recurrence rate for this method
Downside of higher morbidity.
Complete cyst excision
Cysts more than 10cm
To avoid any spillage of contents
Remember hydatid cysts cause fatal anaphylactic reactions on rupture!
Prognosis
90% of untreated Alveolar echinococcosis patients die within 10 years, while treated have a far better prognosis.
Prognosis of Cystic echinococcosis depends on other organ involvement.
Congenital polycystic liver
These cysts are extrarenal manifestations of polycystic renal disease.
It is an inherited disorder caused by a defect in
PKD1 or PKD2 gene leading to dominant type which manifests in adulthood
PKHD1 leading to recessive type which manifests in infancy
Side note Cysts are more common in dominant type
Risk factors for progression to liver
Genetics
Age older than 35
Female sex
Side note Cysts volume is larger in women than men
Contraceptive drugs
Multiple pregnancies
Side note Hepatic cysts epithelial lining is very reactive to estrogen induced growth as they express receptors for it
Signs and symptoms
Like many other cysts classifications, polycystic liver cysts are usually asymptomatic and incidental findings that begin to show symptoms once enlarged.
Big cysts can compress intrahepatic structures along with hepatomegaly inducing
Shortness of breath
Esophageal reflux
Postprandial fullness
Back pain
Increased abdominal girth
Budd-Chiari-like syndrome
Compression of Portal vein can lead to portal hypertension
Varices
Ascites
Jaundice
Encephalopathy
Investigations
Diagnosis is made with imaging studies.
Ultrasound is performed which shows hyperechoic areas in the subscapular regions of the liver while on CT they appear hypodense and well delimited.
Liver function is typically normal.
Management
Three main types of interventions are made for symptomatic patients
Medical therapy
Octreotide
Estrogen receptor antagonists
Surgical
Laparoscopy- the cyst is deroofed and aspirated
Segmental hepatic resection
Only for patients with extreme hepatomegaly and symptoms
Liver transplant
Gives patients a good prognosis
Prognosis and complications
Invasive procedures carry their risk of complications as venous bleeding, bile leaks and sometimes adhesions thus need to carefully be weighed with benefits for a good prognosis.
Other complications
Cyst haemorrhage
Cyst infection
Cyst rupture
Portal hypertension
Jaundice
Biloma
A biloma is defined as an abnormal, well-circumscribed, extra-biliary collection of bile that typically forms following traumatic or iatrogenic procedures of the biliary tree causing bile leakage and subsequent encapsulation and biloma formation.
Encapsulation of the bile leak is thought to be mediate through inflammation in the surrounding abdominal tissues or liver parenchyma, resulting in fibrosis and encapsulation.
Risk factors
Bilomas are most commonly secondary to disruption of the biliary tree by either an iatrogenic or traumatic cause.
