Antibiotics therapy in pediatrics Dr .Ebtihal Elameen Eltyeb Assistant professor Jazan university

objectives To know the types of antibiotics for pediatrics. To know what is the indication for it. The choice of antibiotics. How do antibiotics act. To know the term antibiotics resistance. To know the combination antibiotics therapy

The choice of antibiotics should largely be determined by: source or focus of infection patient's age and immunologic status whether the infection is viral or bacterial is it community acquired or nosocomial

Factors should be considered to choose antibiotic Any history of allergy, toxicity? Is it appropriate for the spectrum I want to cover? What route of admin: oral or i.v? Any factors affecting absorption ? Is it going to reach the site of infection? Any drug interactions? Any serious toxicity eg, hepatic, renal? Does it need monitoring eg aminoglycosides, vancomycin, streptomycin?

What is our current practice?

Prescribing Pattern of Antibiotics in Pediatric Patients in the Jazan Region, Kingdom of Saudi Arabia The mean age of patient on antibiotic was 3.71 ± 3.62. 209 antibiotics were prescribed to the patients and the average number of antibiotics per prescription was 1.45 ± 0.58. Fever (12.5%) and pneumonia (9.7%) were most frequently found diseases in infants, while other diseases constitute 47.9%. Cephalosporin group of antibiotics were most frequently (52%) prescribed antibiotics, followed by aminoglycoside group (17.3%), penicillins (12.5%), macrolides (8.3%) and quinolones (0.69%). Most of the antibiotics were administered parenterally for inpatients. Khaled M Alakhali, et al . RGUHS J Pharm Sci | Vol 4 | Issue 3 | Jul–Sep, 2014

Misuse of antibiotic: A systemic review of Saudi published studies. a high prevalence of antibiotic misuse among Saudi population ranging from 41%-92%, especially among the children. The reasons of this high prevalence are complex, and several contributing factors including cultural factors, behavioral characteristics, socio-economic status, and level of education. Abdul Rahman Alnemri et al .Curr Pediatr Res 2016; 20 (1&2): 169-173

How does antibiotic act? Penicillin on bacterial cell wall (organisms without cell wall won’t be inhibited eg Mycoplasma pneumoniae). Sulphonamides prevent bacteria synthesising folic acid whereas humans can use preformed folate. Generally drugs that act on cell membranes or protein synthesis are more toxic to humans.

Antibiotics acting on cell wall of bacteria Beta lactams: Penicillins, cephalosporins, carbapenems, monobactam Glycopeptides: Vancomycin, teicoplanin

Indications of benzyl penicillin Strep pyogenes sepsis (from sore throat to fasciitis) Pneumococcal pneumonia, meningitis Meningococcal meningitis, sepsis Infective endocarditis (strep) Strep group B sepsis Diphtheria Syphilis, leptospirosis

Broader spectrum penicillin Penicillinase (b-lactamase)-sensitive penicillins Benzylpenicillin (penicillin G, parenteral) Penicillin V (phenoxymethyl penicillin, oral) Penicillinase-resistant penicillins Flucloxacillin Broad-spectrum penicillins Ampicillin Amoxicillin Co-amoxiclav (amoxicillin plus clavulanic acid; Augmentinآ Antipseudomonal penicillins Piperacillin (with tazobactam; Tazocin Ticarcillin (plus clavulanic acid)

Penicillin (cont) Allergy to penicillin is common (1-10% of patients). Those with a history of true allergy to penicillin should not be given any b-lactam antibiotic, including cephalosporins, the carbapenems, and co-amoxiclav

Drugs that used in penicillin allergy Macrolides: erythromycin, clarithromycin (mainly gram positive cover) Quinolones: ciprofloxacin, levofloxacin (mainly gram positive cover) Glycopeptides (serious infections) Fusidic acid, rifampicin, clindamycin (mainly gram positive)

Cephalosporin Cefuroxime: surgical prophylaxis Cefotaxime/ceftriaxone: meningitis nosocomial infections excluding Pseudomonal, Ceftazidime: nosocomial infections including Pseudomonal

Aminoglycosides Gentamicin, amikacin (tobramycin, streptomycin) Mainly active against gram negative bacteria Mainly used to treat nosocomial infections: pneumonia in UTI, septicaemia Limiting factors are nephrotoxicity (and ototoxicity) and resistance Also used in combination

Carbapenems Imipenem, meropenem: have a very broad spectrum activity against gram-negative bacteria, anaerobes, streps Now used to treat gram negative infections eg, E coli, Klebsiella Ertapenem is a new member of the group but its not active against Pseudomonas

Other types of antibiotics Co-trimoxazole ( UTI) Chloramphenicol (typhoid fever, meningitis) Colistin (resistant Pseudomonas) topical Neomycin: gut decontamination, topical

Antibiotics resistance Some bacteria are naturally resistant to particular antibiotics (Pseudomonas has permeability barrier to many antibiotics) Antimicrobial resistance occurs naturally over time, usually through genetic changes. However, the misuse and overuse of antimicrobials is accelerating this process Other species acquire resistance via plasmids (infectious resistance) eg Neisseria gonorrhoeae, many gram negatives

Methicillin-Resistant Staphylococcus aureus (MRSA) These organisms commonly cause hospital-acquired infection and are increasingly common in the community as well. They are resistant to all b-lactams, including flucloxacillin. Consider MRSA as a causative organism if a patient becomes unwell in hospital or does not respond to conventional treatment.

combination antibiotics therapy When treating serious infection empirically (severe pneumonia:cefotaxime+erythromycin) To prevent the emergence of drug resistance: tuberculosis regimens For synergy: Penicillin + gentamycin For mixed infections eg, abdominal sepsis (tazocin+metronidazole)

Case scenario An 8-year-old boy is seen in because of fever, headache, sore throat, and malaise. He’s had no rhinorrhea, cough, or hoarseness. Physical examination reveals a temperature of 39C, exudative pharyngitis, and tender cervical adenopathy How will you treat him?

Larger doses of penicillin once daily result in more relapses* AAP recommends oral penicillin V 2-3 times daily for 10 days, a single dose of benzathine penicillin, or amoxicillin 250 mg/kg tid for 10 days Larger doses of penicillin once daily result in more relapses* *Breese, 1965, Gerber, 1989

Massages to take home Irrational Overuse of antibiotics is the direct cause for resistance. Start antibiotic only if indicated Always use first line drugs Use Microbiology Lab more often Develop culture of culture Spend more time with parents (counseling) Select proper empirical antibiotics Do not use antibiotics in nonbacterial conditions

references Oxford Handbook of Practical Drug Therapy, 1st Edition http://www.uptodate.com/contents/fever-in-children-beyond-the-basics Some lectures about antibiotics therapy