Which of the following is important in the pathogenesis of mycoplasmal infections?
A. The presence of lacto-N-neotetraose with a terminal galactosamine as the host cell receptor.
B. The peptidoglycan in the mycoplasmal cell wall.
C. The structures and the interactive proteins that mediate adhesion to host cells.
D. The absence of cilia on the surface of the host cells.
E. Growth in an anatomic site where anaerobic organisms thrive.
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A 25-year-old medical student has contact with a patient who has pneumonia with fever and cough. Four days later, the medical student develops fever and cough, and chest radiographs show consolidation of the right lower lobe. Routine bacterial sputum culture results are negative. Pneumonia caused by Mycoplasma pneumoniae is considered. All of the following are methods to confirm the clinical suspicion except
A. PCR amplification of Mycoplasma pneumoniae DNA in sputum
B. Culture of sputum for Mycoplasma pneumoniae
Culture of a lung aspirate for Mycoplasma pneumoniae
D. Gram stain of sputum smear
Enzyme immunoassay test of acute and convalescent sera
Initiation of infection by Mycoplasma pneumoniae begins with
A. Elaboration of a polysaccharide capsule that inhibits phagocytosis
B. Secretion of a potent exotoxin
C. Adherence to respiratory epithelial cells mediated by P1 adhesin
D. Endocytosis by ciliated respiratory epithelial cells
E. Phagocytic uptake by alveolar macrophages
The following statements about trachoma are correct except
A. Trachoma is readily prevented by a chlamydial vaccine
B. It follows chronic or recurrent eye infection with Chlamydia trachomatis.
C. Millions of people worldwide have trachoma.
D. Progression of trachoma can be slowed by intermittent treatment with azithromycin
E. Trachoma involves scarring of the conjunctiva, eyelid deformities, and eyelash injury to the cornea.
A 28-year-old woman who is 10 weeks pregnant presents to the obstetrics clinic for prenatal care. She has a history of treatment for syphilis 7 years previously. The results of serologic tests for syphilis are as follows: nontreponemal test, RPR, nonreactive; treponemal test (TP-PA), reactive. Which of the following statements is most correct?
A. The baby is at high risk for congenital syphilis
B. The mother’s previous treatment for syphilis was effective.
C. The mother needs to be treated again for syphilis
D. The mother needs a lumbar puncture and a VDRL test of her CSF for neurosyphilis