Micro Flashcards
(50 cards)
Protein A
Virulence factor in peptidoglycan cell wall of Staph aureus that binds the Fc portion of IgG, leading to impaired complement activation, opsonization, and phagocytosis.
How to visualize Cryptococcus neoformans
India ink staining - stains background black and allows thick polysaccharide capsule of yeast to be visualized
Cryptococcal meningitis presentation
Slowly worsening headache, fever, lethargy in immunocompromised individual
Treatment for cryptococcal meningitis
Amphotericin B and flucytosine for initial treatment. Long term maintenance with fluconazole
CSF findings in cryptococcus meningitis
low glucose, increased protein, mild pleocytosis with predominance of lymphocytes
Which drug is used to treat trichomonas vaginitis and bacterial vaginosis?
Metronidazole
What is the major virulence factor among E. coli strains that cause neonatal meningitis?
K1 capsular antigen
Describe the identifying qualities of Strep pneumo
Gram +, alpha hemolytic, optochin-sensitive, bile soluble, lancet shaped diplococci
What is the mechanism of vancomycin resistance in organisms such as VRE?
Substitution of D-lactate in the place of D-alanine during the process of peptidoglycan cell wall synthesis. This prevents vancomycin from binding to its usual D-alanyl-D-alanine binding site
What are CMV related complications observed in infants exposed in utero?
Chorioretinitis, sensorineural deafness, seizures, jaundice, hepatomegaly, splenomegaly, and microcephaly
Acute rheumatic fever presentation
Migratory arthritis, new onset murmur, fever, and positive antistreptolysin O titer
Primary cause of morbidity in acute rheumatic fever?
Heart failure from severe pancarditis
Adenovirus
Self limiting, year round infection that causes acute onset of fever, cough, congestion, pharyngitis, and conjunctivitis. Outbreaks among those living in close quarters
Name the viruses with segmented genomes
Orthomyxoviruses, reoviruses, bunyaviruses, arenaviruses
Describe parvovirus B19
Nonenveloped single-tranded DNA virus
What infections are transmitted by the Ixodes tick?
Babesiosis and Lyme disease
What is found in tissue samples of patients infected with Coccidioides immitis
Spherules containing endospores
Coccidioides immitis infection
Asymptomatic or can cause pulmonary disease ranging from flu-like illness to chronic pneumonia. Disseminated disease in immunocompromised
What diseases are transmitted by Ixodes ticks?
Babesiosis and Lyme disease
What is the presentation of babesiosis?
Acute febrile illness, thrombocytopenia, hemolytic anemia, abnormal liver fxn tests, and intraerythrocytic inclusions
Describe severe babesiosis. Who is at increased risk?
Acute respiratory distress syndrome - dyspnea, coarse crackles, bilateral infiltrates. Increased risk in splenectomy patients
What microbes primarily account for central venous catheter infections?
Gram positive cocci, primarily coagulase-negative staphylococci and staphylococcus aureus
Blastomyces dermatitidis presentation
In immunocompetent individials - lung infection or flu like illness. In immunocompromised - causes disseminated disease with fever, weight loss, night sweats, cough, dyspnea, skin lesions, and bone pain
Large yeast with a single, broad based bud
Blastomyces dermatitidis
