C.P.C. RUQ Cystic Mass and Fever By William E. Stevens M.D.

CPC Case Highlights Young, Latin-American, Male, Homosexual 2 weeks fever, chills, night-sweats 1 week RUQ pain 5-10 pound weight loss Exam: temp 102.5; RUQ tenderness Labs: normal WBC 5.7, mildly abnormal LFT’s (hepatitis risk factors); elevated total protein to albumin ratio; elevated CRP and ESR CT scan: 8.5 cm cystic / solid mass in RUQ, heterogeneous, non-enhancing walls, IVC thrombosis, ?pushing or invading into liver

RUQ Cystic Mass and Fever Differential Considerations Primary infection Bacterial abscess Amebic abscess Echinococcosis Malignancy Liver Adrenal Renal Pancreatic Lymphoma, other Benign Mass with secondary infection Hepatic cyst with infection or focal cholangitis Pancreatic pseudocyst with infection Choledochal cyst Renal, adrenal, mesenteric and duplication cysts Multiple problems Chronic viral hepatitis with a cystic mass HIV infection with a cystic mass

Bacterial Abscess Pyogenic liver abscess Other abdominal abscesses Symptoms: Fever 90%; pain 55%; weight loss 40%; jaundice 50% Usually multiple 50%; right lobe involved 60% Etiology: biliary 55%, cryptogenic 15%, other: appendicitis, diverticulitis, etc. Other abdominal abscesses Diverticular abscess Perinephric abscess Cholecystitis with abscess Perforated ulcer with abscess Perforated appendix with abscess Treatment Drainage, antibiotics, surgery

Amebic Abscess Entamoeba histolytica Pathophysiology Fecal-oral transmission 5-10% in U.S. are asymptomatic cyst passers Pathophysiology Ingested cyst is resistant to gastric acid Ameba becomes active in small intestine and passes into colon Ameba invade colonic mucosa causing acute and chronic colitis Ameba invade into mesenteric veins thus reaching the liver Cystic necrosis of hepatocytes

Entamoeba histolytica

Amebic Abscess Clinical Presentation More common in young, male, Latin-American, HIV+ 60% have history of travel to endemic country Duration of illness is usually < 2 weeks 20% have history of dysentery, 10% have dysentery 90% have RUQ pain or epigastric, chest or right shoulder pain 75% have fever Right hepatic lobe involved in 80-95% LFT’s mildly, nonspecifically elevated; < 10% jaundice Leukocytosis and anemia are common

Amebic Abscess Diagnosis Ultrasound and CT Usually solitary, round, peripheral, right lobe Through transmission, hypoechogenicity Wall usually enhances with IV contrast Occasionally will have nodular border or internal septations Amebic Serology ELISA has > 90% sensitivity Can’t differentiate past from current infection Liver Aspiration Not usually necessary Pus is reddish brown “anchovy paste”, usually sterile Aspirate if diagnosis is uncertain, large abscess, “impending rupture”, left lobe involvement, non-response to treatment

Amebic Abscess Complications Treatment Pleuropulmonary rupture Hepatic rupture, amebic peritonitis Usually sudden severe abdominal pain Occasionally slow leak with walled off abscess Rupture into pericardium, pericarditis Hemobilia Rupture into bowel Treatment Aspiration if needed Flagyl 750 mg TID for 10 days Iodoquinol 650 mg TID for 20 days

Echinococcosis Echinococcus granulosa and multilocularis Small 3-6 mm tape worms Definitive host: Dog, others Ingests infected viscera Passes eggs into stool Intermediate host: Human, sheep, cattle, others Ingests food contaminated with egg laden feces Egg is digested in small bowel releasing embryo Embryo invades mucosa entering mesenteric veins Embryo become trapped in liver (70%), lung (20%), spleen, kidney, bone, CNS, etc. Endemic in areas where dogs are used to help raise livestock

Echinococcus granulosa

Echinococcus Life Cycle

Echinococcosis Symptoms occur years after acute infection Labs Cyst produces mass effect enlarging ~1 cm/year RUQ pain CBD compression, obstructive jaundice Portal vein compression, portal hypertension Cyst may rupture; contents are highly antigenic Anaphylactic shock Free rupture into peritoneum Rupture into biliary tract: obstruction, pancreatitis, cholangitis Rupture into pleura, pericardium, colon, duodenum, kidney Cysts may become secondarily infected Labs Mild leukocytosis, 40% have eosinophilia ELISA IgG is 97% sensitive Radiology Cystic mass; walls occasionally calcified; rim often enhances with IV contrast Daughter cysts

Echinococcosis CT Appearance

Echinococcosis Diagnosis Treatment Typical radiological appearance MRI provides more data than CT ELISA IgG is 97% sensitive Aspiration is relatively contraindicated due to risk of cyst leakage and anaphylaxis Treatment Surgery: remove all cysts if possible Avoid spillage of cyst contents Large cysts may be injected with hypertonic saline and aspirated in OR before removal 10-30% recur Albendazole 400 mg BID for 28 days Non-surgical injection and aspiration only in unresectable cysts or patients who are non-operable

Neoplastic Hepatic Cysts Any primary or metastatic cancer can appear cystic due to central necrosis or hemorrhage Choriocarcinoma, ovarian carcinoma, sarcoma, islet cell tumors, lymphoma Biliary cystadenoma / cystadenocarcinoma Most common in women over age 40 Cystic, septated masses, irregular wall margins, more often in right lobe Mucous secreting cuboidal epithelium with ovarian type stroma Walls and septations are more vascular by pulse doppler Cavernous hemangioma Most common hepatic tumor; usually asymptomatic Men = women, but estrogens enhance growth Often appear cystic, occasionally pedunculated Rarely will rupture, usually due to trauma Teratoma Mesenchymal hamartoma

Benign Noninfectious Hepatic Cysts Solitary Simple Cysts 3.6% population; F:M = 4:1 Almost always asymptomatic Usually <5 cm, usually right lobe Thin walls; more than one cyst may be present Post-traumatic Post-hepatic infarction Rarely can cause pain, hemorrhage, become infected Polycystic Autosomal dominant adult polycystic kidney disease Autosomal recessive polycystic kidney disease and Congenital hepatic fibrosis Caroli’s Disease Von Meyenburg complexes Other congenital syndromes Peliosis hepatis

Other RUQ Cystic Masses Pancreatic Cysts Simple pancreatic cysts Pancreatic pseudocysts Almost always have a history of pancreatitis or trauma Complicates 10% cases of acute pancreatitis More common in ETOH pancreatitis Usually lack septae; may be loculated; may have calcium; cysts may travel to unexpected areas Cyst fluid has a very high amylase Pancreatic cystic neoplasm 80% are women; usually > 55 years old; usually involve body and tail pancreas Mucinous cystic neoplasm (45%); intraductal papillary mucinous neoplasm (30%); serous cyst adenoma (15%) EUS is best diagnostic test Choledochal Cysts Congenital cystic dilation of the biliiary tract 60% present before age 10 Recurrent RUQ pain, fever, abnormal LFT’s

More RUQ Cystic Masses Adrenal Cysts Renal Cysts Mesenteric Cysts 15% of adrenal cysts are malignant Adrenal cortical carcinoma and adenoma Pheochromocytoma Cystic lymphangioma and neuroblastoma 85% are benign Hemorrhagic adrenal pseudocyst Hydatid cyst Renal Cysts Solitary cysts and Polycystic kidney disease Renal cell carcinoma male > female; usually age > 50; increased risk IVC thrombosis; 60% have hematuria Mesenteric Cysts Very rare; 3% are malignant 60% have localized pain, occasionally fever, chills Duplication Cysts Rare; congenital; attached to gut; lined by G.I. mucosa

HIV Related Liver Diseases Hepatitis B and C Increased incidence in HIV+ patients When compared to HIV negative patients: Higher viral load Lower ALT More severe histology Less responsive to medical therapy Mortality from liver disease much higher Increased risk of Hepatoma and Lymphoma with chronic hepatitis Peliosis hepatis Fever, RUQ pain, hepatic cystic masses usually < 3cm in size Blood filled cavities Related to Bartonella infection; CD-4 count < 200 Amebic abscess 60% of patients without a travel history are immunosuppresed or HIV+ Many others: fungal abscess, Kaposi’s sarcoma, Lymphoma

RUQ Cystic Mass and Fever Diagnostic Studies Recommend: Send serologies for ameba and Echinococcus Send serologies for HIV, Hepatitis B and C Aspirate and Biopsy cystic mass if ameba and Echinococcus serologies are negative