United State Medical Licensing Examination (Step 1) Set 17

Autoantibody testing of a patient with an autoimmune disorder reveals high titers of antibodies against the core proteins of small nuclear ribonucleoprotein particles (Smith antigen). Based on this finding, detection of which of the following is the most important initial clinical feature of this autoimmune disorder?

A newborn has a temperature of 103

Aspecimen of thick, bloody sputum from a hospitalized 80-year-old patient with chronic obstructive pulmonary disease is sent for laboratory analyses. The tests yield heavy growth of a lactose-positive, nonmotile, gram-negative rod with a large gelatinous capsule. Which of the following is this bacterium most likely to be?

A 14-year-old boy presents with acne with inflamed follicles and sebaceous glands. Gram stain of a pustule from his face reveals pleomorphic gram-positive bacilli. Which of the following is the organism implicated in this condition?

A Gram stain smear of spinal fluid from a 2- year-old child reveals short gram-negative rods. Which of the following most likely is the organism?

Which pair of organisms below can be routinely responsible for food poisoning?

A number of children are hospitalized with bloody diarrhea and severe hematological abnormalities. A4- year-old girl dies of kidney failure shortly after admittance. Epidemiological investigation establishes that all of the patients developed symptoms soon after consuming hamburgers from the same fast-food restaurant chain. Which of the following organisms is most likely to be responsible for the outbreak?

Asmall gram-negative pleomorphic organism was isolated from the nasal secretion of a toddler who later had paroxysms of coughing and post-tussive vomiting lasting at least 2 weeks. Which of the following culture media should be used to culture the suspected organism?

Mumps virus accounts for 1015% of all cases of aseptic meningitis in the United States. Which of the following is most true of infection with mumps virus?

A 60-year-old man arrives at the emergency room with chills, high fever, headache, and muscle pain. He is a slaughterhouse worker. Believing he had a flu, the man had stayed at home for 9 days after the onset of the symptoms. You suspect a diagnosis of leptospirosis. What body fluid should the clinical laboratory check for the presence of L. interrogans?