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Mycoplasmas are resistant to penicillins because:

Case Study 1: This 19-year-old student was in his usual state of health until the evening prior to admission, when he went to bed with a headache. He told his mother that he felt feverish, and on the following morning his mother found him in bed, moaning and lethargic. He was brought to the emergency room, where he appeared toxic and drowsy, but oriented. His temperature was 40C, his heart rate was 126/min., and his blood pressure was 100/60 mm Hg. He had an impressive purpuric rash (bruise-like), not blanching, most prominent on his trunk, legs and wrists. A gram stain of the material taken from one of the patient’s skin lesions showed gram-negative diplococci. His white blood cell count was 26,000/ml with 25% band forms. The platelet count was 80,000/ml. Blood cultures were obtained and the patient was begun on intravenous ceftriaxone. Blood cultures subsequently grew the organism seen on the gram stains of the lesions. Case Study 1 Question 5:  What virulence factor of this organism is probably responsible for the purpuric rash?

List two examples of fomites.

Neurotoxin is produced by which anaerobic bacteria? Check all which apply.

Case Study 1:  The patient was a 37-year-old male with hemophilia.  He was HIV positive and had progressed to full-blown AIDS in the past 3 months.  His current medications included factor VIII treatments, suppressive treatment with the antimicrobial agents trimethoprim/sulfamethoxazole, and azidothymidine (AZT).  He presented with a 3-day history of voluminous bloody diarrhea, 10-lb (ca. 4.5-kg) weight loss, and profound dehydration.  Tests for ova and parasites and culture for Salmonella, Shigella, Yersinia, and Campylobacter were negative three times.  He gave no recent travel history, nor had he recently consumed shellfish. Case Study 1.2:  What role do suppressive antimicrobial agents have in predisposing this patient to his current infection?

Which of the following has the most minimal growth requirements (is the easiest to grow)?

Answer the next three questions (A, B, C) concerning Enterobacteriaceae: Question B:   List one organism in the Enterobacteriaceae family that can only be classified as a opportunistic pathogen. 

Surgical removal of the gall bladder is sometimes recommended because of persistence of carrier state in which of the following diseases?

You have a set of plates from a urine culture, one SBAP and one MacConkey, both have greater than 100,000 colonies.  A gram stain indicates the presence of gram-negative bacilli.  You suspect it could either be from the Enterobacteriaceae family or is a Non-fermenter.   You have determined that the organism originated from the Enterobacteriaceae family.  How would you determine if the organism was pathogenic or nonpathogenic?  

Which of the following is NOT a genus of the family Enterobacteriaceae?