A patient attends clinic exhibiting nuchal rigidity, headach…

A patient attends clinic exhibiting nuchal rigidity, headache, and nausea. Your medical team orders a microscopic investigation of the cerebrospinal fluid removed from the meningeal space. The lab reports the presence of bacteria.  You suspect the causative agent is?

The six year-old sister of a Diptheria patient has her throa…

The six year-old sister of a Diptheria patient has her throat swabbed and cultured as a precautionary measure. Her cultures reveal the presence of a Gram-positive, club-shapped bacillus that possesses cytoplasmic granules that exhibit metachromatic staining. What is the MOST PLAUSIBLE reason the sister does not suffer from Diptheria but her brother does?

An immunocompromised patient attends hospital showing eviden…

An immunocompromised patient attends hospital showing evidence of a lung infection. Chest X-rays show no fluid but do indicate the presence of granulomas. Follow-up PPD and interferon-γ tests are negative.  Further tests reveal disseminated infections including meningitis and osteomyelitis (bone infections). The causative agent is most likely:

A 21 year-old female attends clinic with evidence of pharyng…

A 21 year-old female attends clinic with evidence of pharyngitis. Initial treatment with penicillin V does not resolve the infection, leading her physician to believe the original diagnosis of S. pyogenes to have been incorrect. What other microbes might the physician suspect as possible causes of her illness?