RT Book, Section A1 Lowry, Adam W. A1 Bhakta, Kushal Y. A1 Nag, Pratip K. SR Print(0) ID 7452516 T1 Chapter 38. Infectious Diseases T2 Texas Children's Hospital Handbook of Pediatrics and Neonatology YR 2011 FD 2011 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-163924-8 LK accesspediatrics.mhmedical.com/content.aspx?aid=7452516 RD 2024/10/06 AB Table Graphic Jump Location|Download (.pdf)|PrintAntibioticOrganisms CoveredDoseNotesAmpicillinGram-positive organisms (Streptococcus spp.)Susceptible Escherichia coliListeria monocytogenesEmpiric treatment for early- or late-onset (age >72 hrs) sepsis:≤7 d old: 150 mg/kg/dose IV q12h>7 d old: 75 mg/kg/dose IV q6hTreatment >48 h:Meningitis or no CSF obtained: 75 mg/kg/dose IV q6hSepsis without meningitis: 75 mg/kg/dose IV q12hPiperacillinPseudomonas aeruginosa Enterococcus spp.Other Gram-negative enteric and anaerobesPCN-susceptible Staphylococcus spp.Streptococcus spp.≤7 d: 50 mg/kg/dose q8h>7 d: 50 mg/kg/dose q6hModerate CSF penetrationPenicillin GKGBSTreponema pallidumGBS meningitis:≤7 d postnatal age: 450,000 units/kg/d divided every 8 h>7 d postnatal age: 450,000–500,000 units/kg/d divided every 4 hOther GBS infections: 200,000 units/kg/d divided every 6 hNafcillinMethicillin-sensitive Staphylococcus aureusNon-CNS infections:7 d: 25 mg/kg/dose q8h30–37 wk PMA: ≤7 d: 25 mg/kg/dose q12h>7 d: 25 mg/kg/dose q8h>37 wk PMA: ≤7 d: 25 mg/kg/dose q12h>7 d: 25 mg/kg/dose q6hMeningitis:Use 50 mg/kg/dose at same interval as listed aboveCleared primarily by the liver → monitor LFTs on treatmentCan cause interstitial nephritis → monitor renal function weekly on treatmentCan cause bone marrow suppression → monitor CBC weekly on therapyVancomycinAerobic and anaerobic Gram-positive cocci and bacilliMethicillin-resistant S. aureus (MRSA)Coagulase-negative staphylococciClostridium difficileBacillus spp.Ampicillin-resistant Enterococcus7 d: 20 mg/kg/dose IV q18h30–37 wk PMA: ≤7 d: 20 mg/kg/dose IV q18h>7 d: 15 mg/kg/dose IV q12h>37 wk PMA: ≤7 d: 15 mg/kg/dose IV q12h>7 d: 15 mg/kg/dose IV q8h>44 wk PMA (meningitis): 15 mg/kg/dose IV q6hOnly 10%–15% of serum concentration enters CSF.Optimal serum concentration:Trough: 15–20 mcg/mLGentamicin, amikacin, tobramycinBroad Gram-negative bacillus coverageSynergistic against S. aureus, GBS, L. monocytogenes, enterococciGentamicinIndications: early- or late-onset sepsis (age >72 h); covers Gram-negative rods; use for synergy 48 h (>2 doses), draw gentamicin trough before and peak level after the third dose. Monitor BUN/Cr: Optimum levels: peak= 5–10 mcg/mL, trough = 7 d: 3 mg/kg/dose q18h30–37 wk PMA: ≤7 d: 3 mg/kg/dose q18h>7 d: 2.5 mg/kg/dose q12h>37 wk PMA: ≤7 d: 2.5 mg/kg/dose q12h>7 d: 2.5 mg/kg/dose q8hOptimum levels: peak = 8–10 mcg/mL; trough = 7 d: 15 mg/kg/dose q18h30–37 wk PMA: ≤7 d: 15 mg/kg/dose q18h>7 d: 15 mg/kg/dose q12hCSF penetration depends on meningeal inflammation.Monitor peak and trough levels, as these antibiotics can cause nephrotoxicity and ototoxicity.>37 wk PMA: ≤7 d: 15 mg/kg/dose q12h>7 d: 15 mg/kg/dose q8hOptimum levels: peak = 15–40 mcg/mL; trough = 7 d: 10 mg/kg/dose q8h>37 wk PMA: 13 mg/kg/dose q8hPoor CSF penetrationCleared by the liver → monitor LFTs while on therapyFirst-generation cephalosporins (cefazolin, cephalexin)Susceptible Staphylococcus, Streptococcus, and pneumococciCefazolin:≤7 d postnatal age: 20 mg/kg/dose q12h>7 d postnatal age: 2000 g: 20 mg/kg/dose q8hPoor CSF penetrationSecond- generation cephalosporins (cefuroxime, cefoxitin, cefotetan, cefprozil)Same as first generationplusHaemophilus influenzaeE. coliCitrobacterKlebsiellaEnterobacter cloacaeImproved activity over first-generation against β-lactamase–producing organismsLittle data in neonates, so use is limitedThird-generation cephalosporins (ceftriaxone, cefdinir, ...