Infectious Disease Flashcards
During bacterial DNA replication, ________ functions to remove RNA primers via 5’-3’ exonuclease activity and replace them with DNA via 5’-3’ polyermase activity
______ binds dsDNA at origin or replication and unwinds it
_______ or topoisomerase II relieves tension created during unwinding by introducing negative supercoils in DNA
_______ synthesizes RNA primers
________ binds Okazaki fragments together
_________ has 5’ to 3’ polymerase activity and 3’ to 5’ exonuclease activity
DNA polymerase I
Helicase
gyrase
primase
ligase
DNA polymerase III
the key structural feature that enables _______ to undergo rapid genetic shifts through reassortment is the segmented nature of their genomes. Segmented viruses include orthomyxoviruses, rotaviruses, reoviruses, bunyaviruses, and arenaviruses
influenza
sexually active female with verrucous, skin colored genital lesion =
caused by
type of virus
types that result in warts
can infect stratified squamous epithelium, found in the anal canal, vagina, cervix, and __________
condylomata acuminatum
HPV
dsDNA
6 and 11
true vocal cords
encephalitis with hemorrhagic lymphocytic pleocytosis with increase protein and normal glucose, abnormal MRI signal in bilateral temporal lobes =
treatment
competes with dGTP for _______
Herpes simplex virus encephalitis
acyclovir
viral DNA polymerase
4 year old, tender perioral papules and pustules, covered with golden yellow crusts =
bugs =
treatment is topical abx like =
major complication =
ARF usually follows =
Nonbullous impetigo
S aureus, Grp A Beta hemolytic Strep (S pyogenes)
mupirocin
PSGN
untreated Strep Pharyngitis
low grade fever, high serum ALT and AST, +HBsAg =
most likely outcome =
chronic hepatitis with or without cirrhosis and risk of hepatocellular carcinoma, fulminant hepatitis with massive liver necrosis are
Hepatitis B infection
acute hepatitis with complete resolution
much less likely
boy with rapid and irregular movements of hands, funny faces, trouble controlling voice, new systolic murmur, circular faintly erythematous lesions on abdomen =
most likely mechanism for condition is cross reactivity of antibodies directed against GAS antigens, _______, and __________ subsequently attack myosin and lysoganglioside
ARF
M protein
N-acetyl-beta-D-glucosamine
_______ is a topical antifungal used for oral candidiasis and is a polyene antifungal like _________ that act by binding ergosterol in the fungal cell membrane
Nystatin
Amphotericin B
facial pain (eye pain), fever, headache, and black nasal eschar in patient with DKA are highly suggestive of _______ caused by _________. Most cases are rhinocerebral. These fungi appear as broad, ribbon like nonseptate hyphae with right angle branching
how to confirm
if narrow septate hypahe with sharp angle branching?
mucormycosis
Mucor or Rhizopus
mucosal biopsy
Aspergillus
Type I (a and B) ______ are synthesized in response to viral infections, resulting in transcription of antiviral enzymes that ________. These enzymes only become active in the presence of ________ in order to selectively inhibit virally infected cells
Interferons
halt protein synthesis
dsRNA
urethritis (dysuria with discharge) in a young man is likely due to _______ or _______. The standard treatment for the first presumes infection by both organisms. Therefore, ___________ is given for the first, and doxycycline or __________ is given for the second.
The first is a G- intracellular diplococci, the second is an obligate intracellular organism that does not gram stain well
Neisseria gonorrhoeae
Chlamydia trachomatis
ceftriaxone
azithromycin
most cases of IM (fever myalgias malaise, fatigue, splenomegaly) are due to _______ and associated with serum heterophile antibodies that agglutinate horse or sheep erythrocytes. This test is negative in the beginning and positive later. Negative on two separate occasions =
EBV
CMV
erythema infectiosum = red flushed cheeks (slapped cheeks)
virus can also cause aplastic crises in patients with SCD and hydrops fetalis in fetus
Parvovirus B19
IC patient with hemiparesis, visual field defects, and cognitive impairment =
caused by
Progressive multifocal leukoencephalopathy
JC virus
the -navirs (lopinavir) are ______ used in antiretroviral therapy that can cause metabolic complications such as _______
Protease inhibitors
insulin resistance, lypodystrophy, and inhibit p450
South Asia, cough for months, hemoptysis, 15 lb weight loss, acid fast bacilli =
Isoniazid monotherapy would most likely result in ________, so drug regimens with rifampin, streptomycin, ethambutol, and pyrazinamide are used
TB
selective survival of bacterial cells secondary to gene mutation
TB treatment
inhibition of bacterial RNA polymerase =
adverse effects are _____ and _____
inhibition of mycolic acid synthesis =
adverse effects are __________, give ________
unknown mechanism
adverse effect is hepatotoxicity and hyperuricemia
Inhibition of arabinosyl transferase =
adverse effect is
Rifampin
rash, red body fluids
Isoniazid
Neurotoxicity, give VitaminB6/pyridoxine
Pyrazinamide
Ethambutol
optic neuropathy
HIV in prison for 3 years, has TB meningitis, but TB shows significantly decreased activity of intracellular catalase peroxidase. Exhibits resistance to ________, which must be processed by mycobacterial catalase peroxidase to become active
Isoniazid (INH)
infection with Neisseria gonorrhoeae dose not appear to provide lasting protective immunity to reinfection due to the ___________ of microbial antigenic structure
high variability
malaise, fever, painful genital thin walled vesicles on erythematous base with shallow ulcers on labia and tender inguinal lymphadenopathy, Tzanck smear with multinucleated giant cells =
antiviral drugs = nucleoside analogs such as ______, which incorporate into the newly replicating viral DNA and ultimately terminate viral DNA chain synthesis
primary genital herpes, HSV2
acyclovir
2 day history of target rash, not painful, low grade fever, generalized myalgias, intermittent headaches, no LAD or other skin lesions =
rash called =
recent history of =
vector =
Lyme Disease: Borrelia burgdoferi
Erythema migrans
Camping
Ixodes tick
Vancomycin blocks _______ polymerization and can cause red man syndrome and ________
Daptomycin __________ by creating channels and can cause __________, but is inactivated by pulmonary surfactant
Linezolid inhibits _________ by binding the _____ subunit and can result in ________ and optic neuritis
all treatments for
glycopeptide polymerization; nephrotoxicity
depolarizes the cell membrane; myopathy and CK elevation
bacterial protein synthesis, 50S, serotonin syndrome
MRSA
Pt from Kazakhstan as a child, dog at home, hepatomegaly, US shows large liver mass with cystic lesions, dies during surgery to resect the mass
bug =
cyst type =
spilling of cyst contents can cause =
Echinococcus granulosus
hydatid cysts (eggshell calcification)
anaphylaxis
patient, HIV + from Botswana, painful single ulcer on penis, ragged borders, grey exudate, no penile discharge, tender enlarged inguinal lypmh node in right groin =
bug = curved G- rod in clumping pattern
Chancroid
Haemophilus ducreyi