KROK 1 2010 – Question 35 · KROK (Medicine) · Microbiology, Virology, and Immunology
Examination of a patient with pustular skin lesions allowed to isolate a causative agent that forms in the blood agar roundish yellow middle-sized colonies surrounded by haemolysis zone. Smears from the colonies contain irregular-shaped clusters of gram-positive cocci. The culture is oxidase- and catalase-positive, ferments mannitol and synthesizes plasmocoagulase. What causative agent was isolated?
- A. Staphylococcus saprophyticus
- B. Staphylococcus aureus
- C. Staphylococcus epidermidis
- D. Streptococcus agalactiae
- E. Streptococcus pyogenes
Hint
Weigh pigment, haemolysis, mannitol fermentation and plasma clotting together with the cluster arrangement of the cocci to decide which species fits best.
The answer, the explanation and a note on every option are available once you log in. The account is free: topic tests, a mock exam, mistake review and statistics.
More questions on Microbiology, Virology, and Immunology
- In order to determine toxigenicity of diphtheria bacilli a strip of filter paper impregnated with antitoxic diphtherial serum was put on the dense…
- Clinical diagnosis of a female patient was gonorrhoea. What examination method can be applied for confirmation of this diagnosis?
- A patient suffering from periodical attacks caused by inhalation of different flavoring substances was diagnosed with atopic bronchial asthma. IgE…
- Researchers of a bacteriological laboratory examine tinned meat for botulinic toxin. For this purpose a group of mice was injected with an extract…
- During the repeated Widal’s agglutination test it was noticed that the ratio of antibody titers and O-antigens S. typhi in the patient’s serum had…
- 48 hours after tuberculine test (Mantoux test) a child had a papule 10 mm in diameter on the spot of tuberculine injection. What hypersensitivity…