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  #1  
Old 08-04-2012
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Drug Which antibiotic for H.influenzae infection?

An 18-month- old boy is taken to the emergency department because he has a fever and is irritable and lethargic. The mother says the boy was fine when he went to bed the night before. In response to questioning about drug allergies, she says that the boy recently had a severe hypersensitivity reaction to amoxicillin. Neurologic examination shows the obtunded infant to have marked nuchal rigidity. Cerebrospinal fluid (CSF) samples indicate an elevated white blood cell count with 85% polymorphonuclear leukocytes and a decreased level of glucose. Gram stain of the CSF shows numerous gram-negative encapsulated rods. Empiric therapy is begun. When culture and sensitivity results are available, the causative organism is found to be a β-lactamase–producing strain of Haemophilus influenzae. At this point, the most appropriate therapy for the patient would be

a) ampicillin
b) ceftriaxone
c) chloramphenicol
d) clindamycin
e) vancomycin
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Old 08-04-2012
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C..............
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Old 08-04-2012
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chloramphenicol..
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chloramphenicol..
explain plz
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Old 08-04-2012
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explain plz
Can't use ceftriaxone and ampicillin. Vancomycin doesnt cross the BBB(I forgot this ) . Chloramphenicol is a backup drug for meningitis
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Originally Posted by smanthrav View Post
Can't use ceftriaxone and ampicillin. Vancomycin doesnt cross the BBB(I forgot this ) . Chloramphenicol is a backup drug for meningitis
to add.....vancomycin acts only on G+ve organisms so no action against H.influenze
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Old 08-04-2012
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Default Pharma and micro combo

All I knew you gave in question and left me with pharma stuff to deal
Anyways I also think as others it would be chloramphenicol .
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An 18-month- old boy is taken to the emergency department because he has a fever and is irritable and lethargic. The mother says the boy was fine when he went to bed the night before. In response to questioning about drug allergies, she says that the boy recently had a severe hypersensitivity reaction to amoxicillin. Neurologic examination shows the obtunded infant to have marked nuchal rigidity. Cerebrospinal fluid (CSF) samples indicate an elevated white blood cell count with 85% polymorphonuclear leukocytes and a decreased level of glucose. Gram stain of the CSF shows numerous gram-negative encapsulated rods. Empiric therapy is begun. When culture and sensitivity results are available, the causative organism is found to be a β-lactamase–producing strain of Haemophilus influenzae. At this point, the most appropriate therapy for the patient would be

a) ampicillin
b) ceftriaxone
c) chloramphenicol
d) clindamycin
e) vancomycin[/QUOTE]


I will die with B, due to dangerous of chloramphenicol with aplastic anemia in children by lacking the UDP-glucuronyl transferase(Mech. of action:Inhibition of 50S peptidyltransferase). Ceftriaxone, a 3rd generation of cephalosporins which mech. action is a Beta-lactam drug that inhibit cell wall synthesis, can use in meningitis and penetrate the BBB
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ceftriaxone or choramphenicol, give the right answer plz
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my answer C
what about "severe hypersensitivity reaction to amoxicillin", what would happen with a potential adverse efect in relation with penicillin alergy, "gray baby syndrom" It`s likely in premature babies owing Phase II Conjugation deficit, specifically in the glucoronizathion (cloranph and morfine), this big boy is 18 month old boy,, cloranph is freely permeable trought CNS
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Old 08-04-2012
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Default correct answer

The answer is c) chloramphenicol

The patient’s initial clinical and laboratory findings were consistent with the diagnosis of bacterial meningitis. The patient’s medical history would preclude the use of a penicillin, so chloramphenicol would likely have been the choice for empiric therapy. When the organism was found to be a β-lactamase–producing strain of H. influenzae, chloramphenicol would have continued to be the most appropriate therapy, because it has good activity against β-lactamase–positive H. influenzae and has excellent penetration of CSF. This type of meningitis is rare due to immunization.

As for Ceftriaxone - a third-generation cephalosporin, would have been an appropriate choice only if the patient had not had a severe hypersensitivity reaction to a penicillin. There is a 5–12% risk of cross hypersensitivity to cephalosporins in patients who are hypersensitive to penicillins.
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