GTC MICROBIOLOGY EXAMS SCRIPT UPDATED QUESTIONS
AND ANSWERS GRADED A+
✔✔Aminoglycosides are effective against gram ______ bacteria. - ✔✔negative
✔✔What are some side effects of aminoglycosides? - ✔✔Toxicity, hearing loss, kidney
damage
✔✔Tetracycline is considered a ________ antibiotic. - ✔✔broad spectrum
✔✔Tetracycline is effective against intracellular bacteria such as: - ✔✔chlamydia,
rickettsia
✔✔Tetracycline is effective against bacteria without a cell wall such as: -
✔✔mycoplasma
✔✔What is the problem with tetracycline in children? - ✔✔discolors teeth and affects
their bones
✔✔What is special about chloramphenicol? - ✔✔Broad spectrum, it gets through the
blood brain barrier and is great for treating meningititis
✔✔What about the problem associated with it? How serious is that? - ✔✔Toxicity in
children-->aplastic anemia. Suppress the immune system. Very serious causes
suppression of bone marrow and loss of production of WBC and RBC. Only used if
absolutely necessary.
✔✔Which patients get erythromycin? - ✔✔Patients who are allergic to penicillin.
✔✔Name the 2 diseases that are often treated with this drug - ✔✔Legionnaires disease,
atypical pneumonia
✔✔Clindamycin is a broad spectrum antibiotic. Such antibiotics have been associated
with pseudomembranous colitis. What is that? - ✔✔An increase in the # clostridium
difficule which produces a toxin in GI tract serious complication
✔✔Name a drug given to combat VRSA? - ✔✔Oxazolidinones-inhibits 50s and
translation
Streptogramins-drug combo that bind to the 50s unit of gram+
✔✔How do rifampin and quinolones work? - ✔✔Rifampin - block RNA transcription,
penetrates well into CSF/abscesses
Quinolones- inhibit DNA gyrase in prokaryotes; broad spectrum
, ✔✔When is rifampicin given? - ✔✔for TB and meningitis (also chlamydia and rickettsia)
✔✔What is one of its disturbing side effects? - ✔✔red man syndrome - occurs when
rifampicin is given all at once. This causes mast cells and basophils to degranulate thus
causing a "red" effect on skin. This can be prevented by giving smaller doses over a
period of time
✔✔What is a side effect of quinolones? - ✔✔Not given to pregnant women becauses it
can cause a cartilage development in newborns
✔✔How do sulfa drugs work? - ✔✔They inhibit folic acid synthesis. They act as
antimetabolites by mimicking a compound (PABA) needed by bacteria to make folic acid
✔✔What is the advantage of giving sulfa drugs together with trimethoprim? - ✔✔In
combination they block two steps in the formation of folic acid. This ensures no other
synthesis of folic acid occurs
✔✔When are sulfa drugs prescribed - ✔✔UTI, pneumocystics, pneumonia
✔✔Name an antifungal agent given for systemic fungal infections - ✔✔Amphotericin B
✔✔Name an antifungal agent given for topically for skin infections - ✔✔Imidazoles
✔✔How does acyclovir work? - ✔✔Blocks nucleic acid synthesis by incorporating a
"wrong base" into the DNA of a virus so there is no protein synthesis and therefore no
viral replication
✔✔Why is it so difficult to come with antiviral agents? - ✔✔Because viruses lack
organelles and have no cell wall
✔✔Why would interferon seem like a good drug to give for viral infections? -
✔✔Because it blocks formation of viral proteins at the ribosome
✔✔How does AZT work? - ✔✔reverse transcriptase
✔✔Some antiviral drugs are neuraminidase inhibitors. Which virus did we discuss that
has neuraminidase as one of its spikes? - ✔✔influenza
✔✔What would a patient with a Trichomonas vaginalis infection likely be treated with? -
✔✔metronidazole- it prevents replication and transcription of anaerobic protozoan (and
anaerobic bacterial ) infections
✔✔Name an antimalaria drug - ✔✔chloroquine- accumulates in RBC which affects
plasmodia
AND ANSWERS GRADED A+
✔✔Aminoglycosides are effective against gram ______ bacteria. - ✔✔negative
✔✔What are some side effects of aminoglycosides? - ✔✔Toxicity, hearing loss, kidney
damage
✔✔Tetracycline is considered a ________ antibiotic. - ✔✔broad spectrum
✔✔Tetracycline is effective against intracellular bacteria such as: - ✔✔chlamydia,
rickettsia
✔✔Tetracycline is effective against bacteria without a cell wall such as: -
✔✔mycoplasma
✔✔What is the problem with tetracycline in children? - ✔✔discolors teeth and affects
their bones
✔✔What is special about chloramphenicol? - ✔✔Broad spectrum, it gets through the
blood brain barrier and is great for treating meningititis
✔✔What about the problem associated with it? How serious is that? - ✔✔Toxicity in
children-->aplastic anemia. Suppress the immune system. Very serious causes
suppression of bone marrow and loss of production of WBC and RBC. Only used if
absolutely necessary.
✔✔Which patients get erythromycin? - ✔✔Patients who are allergic to penicillin.
✔✔Name the 2 diseases that are often treated with this drug - ✔✔Legionnaires disease,
atypical pneumonia
✔✔Clindamycin is a broad spectrum antibiotic. Such antibiotics have been associated
with pseudomembranous colitis. What is that? - ✔✔An increase in the # clostridium
difficule which produces a toxin in GI tract serious complication
✔✔Name a drug given to combat VRSA? - ✔✔Oxazolidinones-inhibits 50s and
translation
Streptogramins-drug combo that bind to the 50s unit of gram+
✔✔How do rifampin and quinolones work? - ✔✔Rifampin - block RNA transcription,
penetrates well into CSF/abscesses
Quinolones- inhibit DNA gyrase in prokaryotes; broad spectrum
, ✔✔When is rifampicin given? - ✔✔for TB and meningitis (also chlamydia and rickettsia)
✔✔What is one of its disturbing side effects? - ✔✔red man syndrome - occurs when
rifampicin is given all at once. This causes mast cells and basophils to degranulate thus
causing a "red" effect on skin. This can be prevented by giving smaller doses over a
period of time
✔✔What is a side effect of quinolones? - ✔✔Not given to pregnant women becauses it
can cause a cartilage development in newborns
✔✔How do sulfa drugs work? - ✔✔They inhibit folic acid synthesis. They act as
antimetabolites by mimicking a compound (PABA) needed by bacteria to make folic acid
✔✔What is the advantage of giving sulfa drugs together with trimethoprim? - ✔✔In
combination they block two steps in the formation of folic acid. This ensures no other
synthesis of folic acid occurs
✔✔When are sulfa drugs prescribed - ✔✔UTI, pneumocystics, pneumonia
✔✔Name an antifungal agent given for systemic fungal infections - ✔✔Amphotericin B
✔✔Name an antifungal agent given for topically for skin infections - ✔✔Imidazoles
✔✔How does acyclovir work? - ✔✔Blocks nucleic acid synthesis by incorporating a
"wrong base" into the DNA of a virus so there is no protein synthesis and therefore no
viral replication
✔✔Why is it so difficult to come with antiviral agents? - ✔✔Because viruses lack
organelles and have no cell wall
✔✔Why would interferon seem like a good drug to give for viral infections? -
✔✔Because it blocks formation of viral proteins at the ribosome
✔✔How does AZT work? - ✔✔reverse transcriptase
✔✔Some antiviral drugs are neuraminidase inhibitors. Which virus did we discuss that
has neuraminidase as one of its spikes? - ✔✔influenza
✔✔What would a patient with a Trichomonas vaginalis infection likely be treated with? -
✔✔metronidazole- it prevents replication and transcription of anaerobic protozoan (and
anaerobic bacterial ) infections
✔✔Name an antimalaria drug - ✔✔chloroquine- accumulates in RBC which affects
plasmodia
