Exam 11: Travelers Diarrhea: Identifying the Causative Agent

Which of the following binds to class II histocompatibility antigens?

A live attenuated vaccine is not available for protection from HPV-associated cancer because

A 36-year-old female drug abuser has an abscess on her jaw where she lost a tooth from being struck in the face 2 weeks ago. She did not get medical help. You lance the lesion, express some lumpy material with difficulty, and send a swab of the organism to the lab for Gram stain, culture, and susceptibilities. The predominant organism in the Gram stain is a filamentous bacterium that is Gram positive, yet nothing grows in the lab. What is the most likely explanation for why it did not grow?

A 26-year-old man presents with an infected foot from stepping on a nail 2 days ago. The nail penetrated through the sole of his tennis shoe. He sprayed some antiseptic on it and did not seek medical help because he had his last tetanus booster about 1 year ago and he thought that would take care of the wound. The foot is quite inflamed around the wound with a little blue-green pus on the bandage. The organism isolated is a Gram-negative rod that is oxidase positive and does not ferment any carbohydrates. Which organism is most likely?

Chronic inflammatory disease confined to the rectum characterizes

What organism (besides Trypanosoma brucei) is noted for its antigenic variation that leads to its ability to repeatedly reinfect the same person and cause disease and has led to difficulty in vaccine development? Estimates of number of different serotypes are well over 1 million.

A 43-year-old woman develops cervical carcinoma. What viral protein played a role in the development of the carcinoma?

A 17-year-old male visiting his grandparents in Louisiana in August develops a severe unrelenting headache that is not relieved by analgesics. He is very sleepy and complains about an odd odor that he thinks is in the whole house. Primary amebic meningoencephalitis is diagnosed. How was it most likely acquired?

The v-src oncogene of Rous sarcoma virus is a

Which of the following would be found in the urine of a patient with multiple myeloma?

What is the function of the cyclic AMP binding proteins in facultative bacteria?

Six 18-year-old women return from a recent Canadian camping trip with abdominal cramping, gas, pain, and diarrhea that is pale, greasy, and malodorous. They drank untreated stream water on the last 2 days of the trip after losing their water filter. What is the most likely causative agent?

A 26-year-old man presents with cellulitis two days after he is bitten by his girlfriend's cat. What is the most likely dominant organism involved in the infection?

A 14-year-old girl has symptoms that include a low-grade fever, chills, headache, muscle aches, and malaise. A physical examination indicates an enlarged spleen. A Monospot test is negative. The laboratory finding that would confirm a diagnosis would be

What microbe has both a live-attenuated vaccine and an inactivated vaccine currently in routine use? The inactivated one is used for anyone under 2 years or over 60, or for anyone who is immunocompromised in any way.

A 28-year-old man compromised by chemotherapy now has a life-threatening meningitis caused by Histoplasma capsulatum. Which of the following antifungal drugs is fungicidal and appropriate for initial systemic use until the infection can be treated with maintenance therapy?

A 92-year-old male presents with a cough of several months duration. He has been coughing up brownish "stuff." The man is 5?6? tall and his weight is down from 150 to 140 lbs., having lost 10 lbs. in the past 2 months without trying. His tuberculin skin test has been greater than 10 mm the three times you have tested him in the 25 years he has been your patient. The chest radiograph is consistent with reactivational TB. You order Mycobacterium tuberculosis testing and susceptibilities and start him on standard therapy. Luminescent real time PCR confirms M. tuberculosis. What has been the standard medium used to grow M. tuberculosis and what is the standard clue to TB in examination cases?

What characteristic of the influenza A virus allows genetic reassortment?

Which of the following bacterial compounds is important in colonization?

All Shigellae have some invasive capability limited to mucosa of the ileum and colon, but some Shigella dysenteriae strains cause more severe disease. Why?