The patient is a 30-year-old male graduate student from Egypt who has been in the USA for 2 months. He came to the student health clinic complaining of abdominal discomfort and fatigue over a 2-week period, and on the previous evening became nauseated and vomited bright red blood clots. He was referred to the hospital.
Question 1 - Single Best Answer
Individuals from other countries may be infected with organisms not endemic in this country. What are some that might be found in individuals from tropical regions that would not be usual in this country?
A) Shigella, Salmonella, and rotavirus
B) Giardia, Enterobius, Cryptosporidia
C) Leishmania, Schistosomes, Plasmodia
D) Helicobacter, Helminths, Haemophilus ducreyi
E) Clostridia, Chlamydia, Campylobacter
Question 2 - Single Best Answer
While individuals from other countries may have different infections than U. S. natives, they can have a number of the same problems. What problems might you think of in this patient as the MOST likely, not having any other information?
A) Helicobacter infection or other bleeding stomach ulcer
B) esophageal varicose vein or tumor
C) food poisoning due to Salmonella
D) viral hepatitis or leptospirosis
E) viral hemorrhagic fever
On admission to the hospital the patient appeared thin, but well and alert; the physical examination was essentially negative except for moderate hepatosplenomegaly. Rectal examination was negative but a fecal specimen was highly positive for occult blood. The CBC was within normal limits.
Question 3 - Single Best Answer
What are some possible causes of hepatomegaly or hepatosplenomegaly?
A) Epstein-Barr virus
B) Brucellosis
C) Typhus fever
D) Schistosomiasis
E) all of the above
A fiberoptic esophagogastroduodenoscopic examination revealed esophageal varices (distended, varicose veins in the esophagus) as the probable cause of the bleeding. An elevated hepatic portal blood pressure was demonstrated. There were no abnormal venous pressures other than in the portal system and its tributaries. The test results indicated that the portal hypertension was presinusoidal and apparently caused by increased resistance to the hepatic portal blood flow before entering the liver sinusoids.
The patient had no history of chronic liver disease and liver function tests were normal. He remembered no unusual past illnesses but admitted to occasional bouts of diarrhea.
Question 4 - Single Best Answer
What disease could be suspected from what you know of the patients history and the clinical findings up to this point?
A) Viral hepatitis
B) Schistosomiasis
C) Alcoholic cirrhosis
D) A metabolic or myeloproliferative disorder as Banti's syndrome
E) !Idiopathic portal hypertension
Question 5 - Single Best Answer
A tentative diagnosis of Schistosomiasis (blood fluke infection) was made. What tests would confirm this diagnosis?
A) Stool exam (fecal smear) for schistosome eggs
B) Urine sediment exam for schistosome eggs
C) Serologic tests
D) Rectal mucosal biopsy
E) all of the above
Question 6 - Single Best Answer
Microscopic examination of feces and urine for Schistosome eggs was negative. Results of serologic tests will not be available for two weeks. A biopsy of the rectal mucosa was made and examined microscopically. Results are shown. Choose the correct implication from the possibilities below.
A) This biopsy proves the diagnosis of Schistosomiasis
B) From the biopsy the schistosome species can not be determined.
C) In fact there is only one schistosome species to which this patient could be exposed.
D) In any case the species of Schistosome is unimportant in the pathogenesis and nature of the clinical disease.
E) A diagnosis of schistosomiasis establishes the cause of this patient's disease.
Because schistosome infections are often without clinical signs or symptoms, it is important to confirm that infection was the actual cause of the disease. A needle biopsy of the liver was made. Histopathologic changes were limited to the portal tracts. Portal tracts were expanded by dense fibrosis and portal veins were obliterated by the sclerotic process. Embedded in the sclerotic tissue were remains of schistosome eggs.
Liver section 
Higher magnification 
Shown at left is the liver section from a similar but more advances case of schistosomiasis with a striking portal cirrhosis and remants of eggs (arrows). On right is a liver section from an experimental infection showing the initial granulomatous response to schistosome eggs which can progress to portal fibrosis.
Question 7 - Single Best Answer
With a diagnosis of Schistosoma mansoni infection and the biopsy results, which of the following statements would be INCORRECT concerning the patient's disease?
A) the fibrotic reaction to schistosome eggs in the hepatic portal circulation is the probable cause of obstructured portal circulation and portal hypertension.
B) Because adult S. mansoni deposits eggs in veinules surrounding the gut, portal cirrhosis and hypertension are uncommon manifestations of schistosome infection.
C) Hepatosplenomegaly is a common sign of S. mansoni infection.
D) Portal hypertension is the probable cause of the esophageal varices.
E) The intact liver parenchymal cells and normal liver function tests are usual in hepatosplenic schistosomiasis.
Question 8 - Single Best Answer
In considering the treatment of this patient, which of the following statements is NOT applicable.
A) There is an effective drug and the prognosis is excellent.
B) Antihelminth drug treatment is necessary to stop egg production and progressive disease.
C) With complete eradication of infection, the esophageal varices and other sequelae would quickly regress.
D) Recurrent bleeding from esophageal varices can be life threatening and blood transfusions may be needed.
E) There is no danger that the infection will be transmitted and could become endemic in this country.
The patient was treated with praziquantel. He was observed for 2 days, and no bleeding was seen. He was released from the hospital and asked to return within 2 weeks for a reassessment and to notify the physician immediately if the bleeding recurred. He did not return for the followup as requested, but he has remained in graduate school and is presumably free of serious symptoms.
Clinically, Schistosomiasis presents a wide range of diseases; included are gastrointestinal Schistosomiasis, hepatosplenic disease, urinary Schistosomiasis, cardiopulmonary Schistosomiasis, CNS Schistosomiasis and combinations of these. Additionally, Schistosomiasis may be complicated by other infections, for example Salmonella-Schistosome syndrome and Heptitis B/Schistosome disease.
Management of Schistosomiasis varies with the type and severity of the disease. Effective, non-toxic antischistosome drugs are now available. The present case appeares to be hepatosplenic schistomioasis complicated by bleeding vasices which can have serrious consequences. The patient was treated with a single dose of Praziquantel and no other treatment was considered necessary at the time but followup examinations should have been carried out.
Question 9 - Single Best Answer
Schistosome species differ in distribution of the adults within the venous circulation and also in the location and distribution of the eggs. These differences result in different disease manifestations even though the pathogenic mechanism -- inflammatory response to eggs retained in the tissues -- is the same. Which species of schistosome would most likely result in convulsions and epilepsy?
A) S. mansoni
B) S. japonicum
C) S. haematobium
Question 10 - Single Best Answer
Bladder cancer is associated with infection by which Schistosome species?
A) S. mansoni
B) S. japonicum
C) S. haematobium
Schistosomiasis is a major medical and public health problem in many tropical areas with an estimated 200-300 million infected and 800,000 deaths per year. The three species of schistosomes have different geographic distributions but all have a similar infection cycle. Eggs are shed in feces or urine (S. haematobium) and hatch in fresh water.
Question 11 - Single Best Answer
What is the intermediate host for the larval stage of the schistosome?
A) mosquito
B) leech
C) snail
D) oyster
E) water buffalo
Question 12 - Single Best Answer
Many things have been tried to reduce morbidity and limit transmission of schistosomes. Which of the following have been successful?
A) Targeted chemotherapy to limit transmission
B) Prophylactic chemotherapy for those that have been or may be exposed
C) Molluscides
D) Vaccination
E) both A and C have been successful
Question 13 - Single Best Answer
The complex infection cycle of schistosomes would appear to be easily broken and control readily achieved, but schistosomiasis is actually spreading and increasing in prevalence, particularly in Africa. What factors are considered responsible?
A) Increased irrigation necessary for agricultural development
B) Increase and redistribution of human populations
C) Economic and political problems in establishing control programs
D) Resistance of snails to molluscides
E) A, B, C