BACTERIAL INFECTIONS (based on Williams) Flashcards
What is the most frequent bacterial cause of acute pharyngitis?
“Streptococcus pyogenes (Group A Streptococcus).”
What are the common non-life-threatening conditions caused by Streptococcus pyogenes?
“Streptococcal pharyngitis. scarlet fever and erysipelas.”
What is the treatment of choice for streptococcal pharyngitis in pregnant and nonpregnant women?
“Penicillin.”
What is the main factor responsible for the local and systemic toxicity of Streptococcus pyogenes?
“Numerous toxins and pyrogenic exotoxins.”
What is the most common cause of severe maternal postpartum infection and death worldwide?
“Streptococcus pyogenes.”
What percentage of pregnant women are colonized with Group B Streptococcus (GBS)?
“10 to 25 percent.”
What are the potential maternal infections caused by Group B Streptococcus (GBS)?
“Bacteriuria. pyelonephritis. osteomyelitis. postpartum mastitis and puerperal infections.”
What are the fetal complications associated with GBS infection?
“Preterm labor. prelabor rupture of membranes. chorioamnionitis. fetal infections and stillbirth.”
What is the leading infectious cause of neonatal morbidity and mortality in the United States?
“Group B Streptococcus (GBS).”
What is the timeframe for early-onset GBS disease in neonates?
“<7 days after birth (often <72 hours).”
What are the common clinical signs of early-onset neonatal GBS infection?
“Respiratory distress. apnea. hypotension.”
What is the mortality rate of early-onset GBS disease in neonates?
“Approximately 4 percent.”
When does late-onset GBS disease typically manifest in neonates?
“1 week to 3 months after birth.”
What is the most common presentation of late-onset GBS disease?
“Meningitis.”
What is the main method of preventing early-onset GBS disease in neonates?
“Maternal intrapartum antibiotic prophylaxis.”
What is the recommended screening protocol for GBS in pregnant women?
“Universal vaginal-rectal culture screening at 36 to 38 weeks’ gestation.”
What is the first-line prophylactic antibiotic for intrapartum GBS prevention?
“Penicillin G.”
What are alternative antibiotics for GBS prophylaxis in penicillin-allergic patients at low risk for anaphylaxis?
“Cefazolin.”
What antibiotic is used for GBS prophylaxis in penicillin-allergic patients at high risk for anaphylaxis?
“Clindamycin or vancomycin.”
What is the preferred approach for intrapartum GBS prophylaxis in women with unknown GBS status?
“Risk-based prevention strategy.”
What is the recommended treatment for asymptomatic bacteriuria caused by GBS?
“Antibiotic treatment if colony count ≥105 CFU.”
What percentage of neonates with early-onset GBS sepsis are born to mothers with negative antenatal screening results?
“53 percent.”
What type of bacteria is Methicillin-resistant Staphylococcus aureus (MRSA)?
“A pyogenic gram-positive organism.”
What is the most common site of MRSA colonization?
“Nares (nose).”
What is the most common MRSA presentation in pregnant women?
“Skin and soft tissue infections.”
What are two common MRSA-related infections in postpartum women?
“Mastitis and breast abscesses.”
What is the first-line antibiotic for severe inpatient MRSA infections?
“Vancomycin.”
What is the recommended treatment for uncomplicated superficial MRSA infections?
“Drainage and local wound care.”
What is the causative agent of Listeriosis?
“Listeria monocytogenes.”
How is Listeria monocytogenes most commonly transmitted?
“Foodborne (contaminated dairy. fruits. vegetables. and processed meats).”
What type of infections can Listeria monocytogenes cause in pregnant women?
“Febrile gastroenteritis. sepsis and CNS infections.”
What is the recommended treatment for Listeriosis?
“Ampicillin plus gentamicin.”
What classic fetal infection pattern is associated with Listeriosis?
“Granulomatosis infantiseptica (disseminated microabscesses and granulomas).”
What is the primary method of Listeriosis prevention?
“Avoiding high-risk foods and proper food hygiene.”
What is the most common cause of foodborne illness from Salmonella species?
“Salmonella typhimurium and Salmonella enteritidis.”
What is the incubation period for nontyphoidal Salmonella gastroenteritis?
“6 to 48 hours after exposure.”
What are the primary symptoms of Salmonella gastroenteritis?
“Nonbloody diarrhea. abdominal pain. fever. chills. nausea and vomiting.”
What is the preferred treatment for uncomplicated Salmonella gastroenteritis?
“Rehydration with intravenous crystalloid solutions.”
When are antibiotics recommended for Salmonella infections?
“When complicated by high fever or bacteremia.”
What is the causative agent of Typhoid fever?
“Salmonella typhi.”
What is the preferred empirical treatment for typhoid fever?
“Fluoroquinolones or third-generation cephalosporins.”
What are the severe complications of untreated typhoid fever?
“GI bleeding. intestinal perforation. encephalopathy. renal failure. cardiovascular collapse.”
How is typhoid fever transmitted?
“Oral ingestion of contaminated food. water or milk.”
What vaccines are available for typhoid fever?
“Two licensed vaccines in the United States.”
How is Shigellosis transmitted?
“Fecal-oral route.”
What is the causative agent of Shigellosis?
“Shigella species.”
What is the typical clinical presentation of Shigellosis?
“Watery or bloody diarrhea. abdominal cramping. fever. vomiting and tenesmus.”
What are severe complications of Shigellosis?
“Toxic megacolon. seizures. meningitis. hemolytic uremic syndrome.”
What are the antibiotic options for Shigellosis during pregnancy?
“Fluoroquinolones. ceftriaxone or azithromycin.”
What is the causative agent of Lyme disease?
“Borrelia burgdorferi.”
