Case Discussion Alveolar echinococcosis mimicking malignant hepatic tumor <Chief Complaint>      A 28-year-old male with progressive jaundice for one month <Brief History>      A 28-year-old male Tibetan (西藏人) suffered from poor appetite, malaise, and progressive jaundice for one month. He also reported to have a weight loss of six kilogram in two months, associated with The stool was clay-colored stoool. There was no history of fever, abdominal pain, diarrhea, or tuberculosis. He denied history of close contact with neither foxes nor other animals. He was a preacher (喇嘛) and had traveled to Nepal, India, Singapore, Malaysia, and Hong Kong in recent six years. He stayed in Taiwan most of the time in recent two years. <Physical Examination>      Physical examination revealed marked icteric sclera and yellowish skin discoloration of the face, trunk, and proximal limbs. The heart rate was 84 bpm, temperature was 36.9 ℃, blood pressure was 116/70 mmHg. His breathing sound was clear and there were no heart murmurs. Palpation of abdomen disclosed hepatosplenomegaly. There was no palpable lymphadenopathy of the neck, axilla, and inguinal areas. <Laboratory and Image Study> 1. CBC/DC WBC Hb PLT Seg Mono Eos Baso Lym PT PTT K/μL g/dL K/μL % % % % % sec sec 8.8 12 141 61 5 11 3 20 19.2/11.2 35.2/33 2. Biochemistry BUN Cr Na  K Alb Globulin Glu CRP mg/dL mg/dL meq/L meq/L g/dL g/dL mg/dL mg/dL 20 1.2 142 3.9 4.0 3.6 102 1.4  AST ALT ALP r-GT Bil (T/D) CEA CA19-9 AFP mg/dL mg/dL meq/L meq/L mg/dL  ng/ml  U/ml   71 44 1040 45 22.5/20 0.92  47.9 < 20 3. Urine analysis: Appearance Sp.gr PH Protein Glu Ketone Clear 1.006 6.0 -- -- -- OB Urobilinogen (EU/dL) WBC (/HPF) RBC (/HPF) Cast (/LPF) Crystal (/LPF) -- 1.0 0-1 0-1 -- --   An abdominal sonography ( Fig. 1 ) : a huge heterogeneous and ill-defined hepatic mass ( up to 13 centimeter). The internal echo pattern of the lesion was inhomogeneous. The mass contained dense calcification with acoustic shadowing. The intrahepatic bile ducts were dilated. Stool and bile : no parasite Serology test for B. abortus and B.melitensis : negative Bile and liver specimen:       AFS: negative; TB culture : negative ;TB-PCR was negative CT scan of abdomen ( Figure2A. 2B ): a huge well-defined lobulated low density soft tissue mass (measured as 12x12x11cm) with central amorphous, extensive calcification. MRCP: a huge hypovascular tumor causing dilatation of the IHDs. The GB and CBD were collapsed. T1W images revealed mostly low signal intensity with patches of slight high signal intensity scattered in the posterior aspect. The tumor was iso to slightly hyperintense in mild T2 pulse sequence but became hyperintense in heavy T2W image with scattered cystic changes. Angiography showed tumor blood supply from celiac trunk and vascular invasion of right portal vein, intrahepatic IVC and infra-hepatic IVC.    <Course and Treatment >        His prothrombin time (PT) was prolonged (19.2 sec, control 11.2 sec), which was corrected by vitamin K1 administration. Percutaneous biliary drainage tube was inserted to relieve the obstructive jaundice. Bile was sent for analysis but no parasite or eggs were found. Culture for bacteria, fungus and tuberculosis were all negative. Liver biopsy was performed. The histology showed necrotic tissue, plasma cell with some eosinophil infilatration and cholestasis. No parasite could be identified. Acid-fast stain was negative. Culture of liver specimen for bacteria, fungus, and tuberculosis were all negative. He underwent surgical resection of right hepatic lobe (Figure3). The postoperative course was uneventful. The histology revealed multilaminated membrane without scolices, which was compatible with alveolar echinococcosis of liver (Figure4A. 4B ). Albendazole was given for six months.    <Analysis>        泡型包蟲病 (alveolar echinococcosis) 是一種很罕見但致命力卻很高的寄生蟲疾病，它與較常見的囊型包蟲病 (cystic echinococcosis) 不論在臨床的表現、影像學的特徵、治療的方式或是預後情形方面，都有許多不同之處。囊型包蟲病 (cystic echinococcosis)是由單房性包蟲(Echinococcus granulosus)感染所導致，而泡型包蟲病 (alveolar echinococcosis)則是由多房性包蟲(Echinococcus multilocularis)感染所導致。後者會造成多房性囊腫，也可能會形成實質性腫塊，甚至會有類似惡性肝腫瘤侵犯至血管或附近的器官的表現。我們報告了一個表現類似惡性肝腫瘤之泡型包蟲病(alveolar echinococcosis)的病例。一位28歲的男性西藏喇嘛，因為一個多月來漸進性黃膽伴隨體重減輕到醫院求診，理學檢查發現肝臟腫大及黃膽，抽血檢查發現嗜酸性白血球升高( 904/mm3)，以及肝功能異常(Bil T/D= 22.5/20mg/dL, ALT=44U/L, AST=71U/L, ALK-P=1040 U/L)，腹部超音波發現肝臟右葉有一12x11x11cm之高回音腫瘤，腫瘤內部呈現部分鈣化及壞死的情況，肝內膽管因腫瘤壓迫而造成擴張，同時發現有侵犯至下腔靜脈、部分肝內靜脈、右側肝門脈以及右側腎上腺的情形。電腦斷層檢查呈現低密度腫瘤併部分鈣化，打入顯影劑後腫瘤部位並無顯影。核磁共振檢查在T1-造影下呈現低訊號腫塊，T2-造影下呈現高訊號腫塊，亦含有部分鈣化及少許小的囊腫，腫瘤之血管供應並不豐富。之後病患接受經皮穿肝膽汁引流。糞便及膽汁的檢查及培養沒有特別的發現，血清腫瘤指數並未明顯升高。肝臟切片檢查顯示淋巴球及嗜酸性白血球浸潤及部分肉芽組織及壞死，但並未發現惡性細胞、致病菌或寄生蟲。病人於黃膽改善之後接受右肝切除，病理檢查證實為多房性包蟲(Echinococcus multilocularis)感染。術後病人復原狀況良好並接受albendazole 400mg bid 治療。泡型包蟲病(alveolar echinococcosis)在台灣並沒有正式的報告病例，此一病例亦為境外移入之個案，但隨著兩岸之間交流日益頻繁，國內醫師在發現肝臟腫瘤但無惡性腫瘤證據或臨床上有寄生蟲感染之跡象時，必須把多房性包蟲(Echinococcus multilocularis)感染也列入鑑別診斷之一。  References: Bresson et al. A twenty-year history of alveolar echinococcosis: analysis of a series of 117 patients from eastern France. Eur J Gastroenterol Hepatol 2000; 12: 327-336. Sasaki F et al. Imaging diagnosis of alveolar echinococcosis in young patients Pediatr Radiol 1997; 27:63-66 Eckert et al. Echinococcosis: an emerging or re-emerging zoonosis? International Journal for Parasitology 2000; 30: 1283 – 1294 Romig et al. An epidemiologic survey of human alveolar echinococcosis in southwestern Germany. Am J Trop Med Hyg 1999; 61: 566-573            繼續教育考題 1. (A) Which of the following is true about human cystic echinococcosis？ A Echinococcus granulosus is the causal pathogen B Echinococcus multilocularis is the causal pathogen C The infection behaves as a slow-growing malignant tumor D All of the above 2. (B) Which of the following is true about human alveolar echinococcosis？ A Echinococcus granulosus is the causal pathogen B Echinococcus multilocularis is the causal pathogen C Most patients (as many as 80%) have single organ involvement and harbor a solitary cyst D All of the above 3. (E) Which of the following is true about the epidemiology of echinococcosis？ A E. granulosus occurs practically worldwide B E. multilocularis is found worldwide, mostly in northern latitudes, including central Europe and the northern parts of Europe, Asia, and North America. C E. vogeli and E. oligarthrus occur in Central and South America. D A+B E A+B+C 4. (C) Which of the following is false about E. multilocularis infection? A Fox is the definitive host of E. multilocularis B Small rodents are intermediate hosts of E. multilocularis C Human is the definitive host of E. multilocularis D All of the above are true 5. (E) How does human became infected with E. multilocularis ? A Humans are accidental hosts and typically not involved in the life cycle of the organism B Ingesting food items contaminated with stool from foxes or coyotes C By petting or handling household cats and dogs infected with the E. multilocularis tapeworm D A+B E All of the above 6. (D) Which of the following is true about clinical manifestation of E. multilocularis infestation? A Liver is the primary site in virtually 100% cases B The cysts are rapid growing and most patients died within 5 years after infection C Symptoms may mimic those of liver cancer and cirrhosis of the liver (destructive growth, invasion, metastasis) D A+C E All of the above are true 7. (A) Which of the following is false about serology diagnosis for E. multilocularis infestation? A Eosinophilia is present in almost 100% of infected patients B ELISA results using recombinant and purified antigens of E multilocularis (Em2+) are positive in 95% of cases and have better specificity (commercially available) C ELISA using the purified alkaline phosphatase of E multilocularis is both highly sensitive and specific (nearly 100%) but is not commercially available. D All of above are true 8. (C) Which of the following is false about image diagnosis of E. multilocularis infestation? A In most cases, ultrasonographic images show a pseudoneoplastic intrahepatic mass with heterogeneous ultrasonographic structure that is mainly hyperechoic and contains scattered calcifications and irregular poorly defined edges B CT scanning shows typical calcifications inside the lesions C MRI is effective for showing typical calcifications inside the lesions D All of the above are true 9. (C) Which of the following is true about the treatment of alveolar echinococcosis of liver? A Most patients (>90%) could be treated with high dose chemotherapy with benzimidazoles (eg, mebendazole, albendazole) alone without surgical treatment B Surgical resection is reserved for those failed to resolve with high dose benzimidazoles C If operation is feasible and if resection of the entire parasitic lesion from other affected organs is possible, surgery is the first treatment choice D A+B 10. (D) Which of the following is false about prognosis of E. multilocularis infestation? A Prognosis has improved markedly during the past 20 years because of earlier diagnoses, better management, and medical treatment with benzimidazoles B actuarial survival rate at 5 years improved from 67% for patients diagnosed from 1972-1982 to 88% for patients diagnosed from 1983-1993 C Patients who receive transplants have a 5-year survival rate of 46%. D All of the above are true