The Quizzes about Parasitology – Part 1

Babesiosis is a tick-borne disease, caused by intraerythrocytic parasites of the genus Babesia, resulting in affecting persons with malaise, nausea, fever, sweats, myalgia, and arthralgia and could be confused with Plasmodium falciparum ring form in red cells. Infection with Babesia has been most commonly observed in which of the following?

Flagellate parasite is the cause of vaginalis in women in temperate areas. It is a sexually transmittable disease. The prominent symptom is copious fowl-smelling yellow discharge that can be accompanied by cervical lesions and abdominal pain. What parasite does this represent?

A 30-year-old female stores her contact lenses in tap water. She notices deterioration of vision and visits an ophthalmologist, who diagnoses her with severe retinitis. Culture of the water as well as vitreous fluid would most likely reveal which of the following?

A young nurse in a South American city located in the tropics develops classical symptoms of malaria. An accurate diagnosis of the Plasmodium species is necessary to provide the best treatment to insure recovery and prevent relapse. Sporozoites from a mosquito bite rapidly enter live cells where asexual merozoites enter the blood stream and RBCs are invaded. This erythrocytic stage provides a basis for laboratory diagnosis. Which of the diagnostic characteristics of P. falciparum is best described by the following?

After returning from a wilderness camping outing, several children report watery, greasy, and foul-smelling stools. The life cycle of the parasite responsible for this outbreak consists of two stages: the cyst and the trophozoite. Which of the following is the most likely identification of this organism?

A working mother takes her 4-year-old child to a day-care center. She has noticed that the child’s frequent stools are nonbloody with mucus and are foul smelling. The child has no fever, but does complain of “tummy hurting.” The increase of fat in the stool directs the pediatrician’s concern toward a diagnosis of malabsorption syndrome associated with which of the following?

The proglottid was purged from the intestinal tract of an individual who recently immigrated to United States from Nicaragua. The proglottid measured 10 mm in length. What species does it represent?

Many of the POWs who were held captive in the Far East during the WWII contracted various parasitic infections, especially those prisoners who were forced to work on the infamous Thai-Burma railway. The tropical jungle environment of the Burma (Myanmar) railway project provided perfect conditions for development of the infective stage of a parasite larva, which infected the POWs through the soles of their poorly shod feet as they worked. In patients who have this chronic infection and are on chronic corticosteroid therapy, a syndrome can occur which results in high mortality rates. Which of the following parasites is most likely to be the culprit?

Several diagnostic tests for antibodies to Toxoplasma are directly compared for sensitivity and specificity against the sera of 100 healthy adults. While differences are apparent in the accuracy of the tests, it is able to conclude that 80% of those tested have IgG antibodies against Toxoplasma. Which of the following is most compatible in helping to explain this finding?

A 32-year-old homosexual man presents to his physician with non-bloody, foul-smelling, greasy stools 3 weeks after traveling to Mexico. While certain enteric protozoan and helminthic infections have been long related to contaminated food or water, sexual transmission of these diseases has produced a “hyperendemic” infection rate among homosexual males. Which of the following organisms is the most likely etiologic cause of this patient’s diarrhea?

Analysis of a patient’s stool reveals small structures resembling rice grains; microscopic examination shows these to be proglottids. Which of the following is the most likely organism in this patient’s stool?

An AIDS patient complains of headaches and disorientation. A clinical diagnosis of Toxoplasma encephalitis is made, and Toxoplasma cysts are observed in a brain section. Which of the following antibody results would be most likely in this patient?

A young boy from an impoverished area in Argentina presents to a public health clinic with Romana sign and a chagoma lesion. Several reduviid insects from the home are shown to the health care workers. In the chronic stage of this disease, where are the main lesions usually observed?

A woman who recently returned from Africa complains of having paroxysmal attacks of chills, fever, and sweating. These attacks last a day or two at a time and recur every 36 to 48 hours. Examination of a stained blood specimen reveals ringlike and crescent-like forms within red blood cells. Which of the following is the most likely infecting organism?

A young woman reports to her physician with possible urinary tract infection. The doctor finds the vagina and cervix tender, inflamed, and covered with a frothy yellow discharge. Which of the following protozoa described in this case is known to exist only in the trophozoite stage?

An international photographer returns to the United States from a global picture assignment. He is seen by his physician, giving his major complaint as diarrhea. Which of the following can be ruled out?

A medical technologist visits Scandinavia and consumes raw fish daily for 2 weeks. Six months after her return home, she has a routine physical and is found to be anemic. Her vitamin B12 levels were below normal. Which of the following is the most likely cause of her vitamin B12 deficiency anemia?

A renal transplant patient is admitted for graft rejection and pneumonia. A routine evaluation of his stool shows rhabditiform larvae. Subsequent follow-up reveals similar worms in his sputum. He has no eosinophils in his peripheral circulation. Which of the following is the most likely organism?

A 56-year-old male immigrant from Bolivia complains of abdominal pain and cramping. He comments that 2 months previous to his current problems, he had numerous bloody stools every day. Physical findings include right upper quadrant pain over the liver with hepatomegaly, and a liver biopsy is performed. Which of the following parasites would most likely be identified in the liver biopsy?

Human malarial infections start with the bite of a mosquito, and patients may experience the periodic paroxysms of this infection due to events that occur in the bloodstream. Up to one million deaths worldwide have been estimated annually. Which of the following control methods for this disease is currently most effective?