another review of 5+ Flashcards
which cells are CD4+
naive T cells
T cells that have been activated through MHC Class II have many possible functions:
- Activate neutrophils through IL17 - this is the only function performed by Th17 (a certain type of T helper cell).
- Increase eosinophil number through IL5 - done by Th2
- Activate B cells through IL4 - done by Th2
- Activate mast cells through IL4 - done by Th2
what is c difficile
gram positive bacili
What is the primary infection target of the Plasmodium species, once its matured sporozoites (merozoites) have been released into the bloodstream?
erythrocytes
A patient presents to you as a GP with fever, diffuse abdominal pain, and constipation that is close to causing bowel perforation. They tell you that recently they stayed on Safari, and did not have access to clean water, and believe they may have drunk water contaminated with faecal matter. You take a stool sample, and send it for assessment.
Which of the following would you be most likely to see on a Gram Stain of this stool sample? (1 mark)
A gram negative rod is the most likely thing to be seen on this patients stool culture. This is because the patient is likely to have typhoid, caused by the bacteria salmonella typhi (a gram negative rod).
This history indicates Salmonella Typhi infection,which is a gram negative rod.
Which of the following categories of defects makes the patients especially vulnerable to viruses?
Patients who have T cell defects and antibody defects are at the highest risk of viral illness.
What type of primary immunodeficiency defect is most likely to be present in a patient presenting with recurrent viral infections?
A T-cell defect is the most likely cause of primary immunodeficiency in a patient presenting with recurrent viral infections. This is because the T cells cannot be activated through MHC Class I when a cell displays intracellular pathogens.
To which of the following bacteria would a patient who underwent a splenectomy be most susceptible to?
Patients who have undergone a splenectomy are most at risk from bacteria that are encapsulated, like haemophilus influenzae. Other examples include streptococcus pneumoniae and neisseria meningitidis.
Which of the following treatments are needed in a case of necrotising fasciitis?
‘IV antibiotics’ and ‘antibody transfusion’.
virulence factors for S. pyogenes?
M protein - inhibits activation of the alternative complement path.
- Hyaluronic acid capsule - prevents recognition and phagocytosis.
- Pyrogenic exotoxins - cleave IgG
- Streptokinase - dissolves clots converting plasminogen into plasmin.
- DNAses - degredation of DNA
What is the term used to describe the rash caused by a complication of streptococcal pharyngitis?
Scarlatinform rash, a rash presenting with diffuse redness with small papules
On which basis are streptococci grouped following Lancefield’s classification?
The Lancefield grouping strategy is done based on the antigens present on the cell wall.
