INFECTIOUS DISEASES Flashcards
What is the coagulase status of Staphylococcus aureus?
Coagulase positive
What is the most common cause of pyogenic infection of skin and soft tissue?
Staphylococcus aureus
What is the role of teichoic acid in Staphylococcus aureus?
Adhesion to mucosal cell
What interferes with opsonophagocytosis in Staphylococcus aureus?
Slime layer
What is the function of Panton-Valentine leukocidin (PVL) in Staphylococcus aureus?
Causes protein leakage leading to cell death and pus formation
Which condition is associated with Panton-Valentine leukocidin (PVL) and Staphylococcus aureus?
Necrotizing pneumonitis
What is the most common cause of osteomyelitis and suppurative arthritis in children?
Staphylococcus aureus
What is the most important preventive measure for Staphylococcus aureus infections?
Handwashing technique
What are the key features of Toxic Shock Syndrome (TSS)?
Acute multisystemic disease characterized by fever, hypotension (shock), erythematous rash, and subsequent desquamation on hands and feet
What is a mnemonic for remembering Toxic Shock Syndrome symptoms?
T (temperature/fever), S (shock/hypotension), S (skin/erythematous rash)
What are the nonspecific symptoms of Toxic Shock Syndrome?
Vomiting, diarrhea, myalgia, nonfocal neurologic abnormalities, conjunctival hyperemia, and strawberry tongue
What is the age group most commonly associated with tampon-induced Toxic Shock Syndrome?
15-25 years old
What is TSST-1 and its role in TSS?
A superantigen causing massive fluid loss from intravascular space
Which bacterial species is most associated with indwelling foreign devices and nosocomial neonatal infections?
Coagulase-negative staphylococci
What is the most common pathogen associated with CSF shunt meningitis?
Staphylococcus epidermidis
What is Staphylococcus saprophyticus most commonly associated with?
Primary UTI in sexually active females
Describe the morphology of Streptococcus pneumoniae.
Gram-positive, lancet-shaped, polysaccharide-encapsulated diplococcus
What impedes phagocytosis in Streptococcus pneumoniae?
Capsular polysaccharide
What are the common diseases caused by Streptococcus pneumoniae?
Bacteremia, bacterial pneumonia, otitis media, and meningitis in children
What should be performed in cases where Streptococcus pneumoniae is resistant to erythromycin but sensitive to clindamycin?
A D-test to determine inducible clindamycin resistance
For children at high risk, what prophylaxis is recommended for Streptococcus pneumoniae?
Penicillin prophylaxis
What is the most common cause of infection in the upper respiratory tract and skin in children?
Group A Streptococcus (Streptococcus pyogenes)
What are two distinct clinical entities caused by Group A Streptococcus?
Scarlet fever and erysipelas
What exotoxins are responsible for the rash in scarlet fever?
Exotoxins A, B, and C
