Dr. Pramod Jog *
Associate Professor, Department of Pediatrics
D.Y. Patil Medical College Pimpri-Pune - 411018. *
Antibiotic Therapy of bacterial infections in the most important scientific development of 20 th Century Medicine. It contributes significantly to the quality of life and reduces the morbidity and mortality due to infectious diseases. The selection of an antibiotic depends not only upon its antimicrobial spectrum but also upon its pharmacologic attributes, resistance potential, safety profile and cost. Pediatricians should develop a rational mindset towards antibiotic therapy.
Keywords : Antibiotics, Antibiotic Therapy, Rational Drug Therapy, Guidelines
The very fact that an article on Rational Antibiotic Therapy is being written means that a lot of irrationality probably exists in this area.
Before discussing the academics of the subject, let us dwell a while on the world 'Rational' Rational means based on logic.
The word Rational primarily is not an adjective for antibiotic therapy but it reflects the mindset of the person prescribing antibiotics. Therefore Rational Antibiotic Therapy would mean antibiotic therapy given by pediatrician with a rational mindset.
|Why is it important to be rational|
|Quite a few pediatricians keep getting information from the medical representatives. The pediatrician is so busy with his work that the hardly finds time to get accurate information regarding efficacy, safety, suitability and cost.
To remember all the relevant information is humanly impossible. Hence he resorts to Academic Gurus in the form of medical representatives.
The detailing by medical reps is aggressive and puts tremendous pressure on the practicing pediatrician. They focus the brighter side and conceal the negative points.
Many a times the antibiotic being promoted does not have any specific advantage over the one, which is time, tested, safe and cost effective.
The pediatrician starts using the new antibiotic just for the sake of novelty.
This tendency results in rapid emergence of resistance to the newly introduced antibiotic. It also unnecessarily taxes parents to pay for new drug. The safety profile of many of these drugs is known only in the long run.
Until recently recognition of new resistant clones was balanced by the promise of newer and more potent antibiotics. Today fewer new classes of antibiotics are under development. Hence clinicians are facing limitations in their ability to treat some serious bacterial infections.
The oversimplified notion of drug of choice i.e., what drug for what bug has changed to other factors critical in the selection of an antimicrobial agent.
Currently we appreciate that the selection of an antibiotic rests not only upon its antimicrobial spectrum, but also upon its pharmacokinetic and pharmacodynamic attributes, resistance potential, safety profile and cost.
Rational Antibiotic Therapy is based on the following 4 things:
- Knowledge of the organism
- Site involved
- Natural course if untreated
Irrational Antibiotic Therapy therefore would mean either of the following:
- Choice of the antibiotic is wrong
- Dose is inadequate
- Duration is inadequate
To decide the choice of antibiotic one should know the organism. On many occasions it is difficult to identify the organism and here selection of an antibiotic is an educated guess.
This educated guess depends on:
- System involved
- Prevalent behavior of the organism as regards sensitivity and resistanceli>Epidemiology
|Mindset while choosing antibiotics|
- Make a precise
clinical diagnosis from the symptoms, signs and investigations e.g., in a case of pyogenic meningitis the diagnosis could be suspected as follows:
- Symptoms: Fever, irritability, altered sensorium, refusal of feeds, vomiting.
- Signs: Febrile, irritable child with altered sensorium, signs of raised intracranial tension, signs of meningeal irritation, variable neurological signs.
- Investigations: CSF examination, WBC count, sugar, protein, CSF culture.
- Consider possible etiologic agents - H. Influenzae, S. Pneumoniae, N, Meningitides rare.
- Target the most likely ones after consideration of age, h/o trauma, h/o neurosurgical procedure etc.
- Specify the therapeutic objectives.
- Eradication of bacteria and sterilization of CSF at the earliest by use of bactericidal drugs • Clinical Cure • Prevention of relapse • Prevention of early and late complications, sequel and mortality.
- Consider the seriousness of illness.
- Make an inventory of effective group of drugs. Bactericidal agents penicillins, Chloramphenicol, 3rd generation cephalosporins, vancomycin etc.
- Choose the most appropriate and effective group based on the criteria of efficacy, safety, suitability and cost.
- Choose an appropriate antibiotic from the chosen group.
- Decide route of administration, dosage schedule and standard prescribed duration.
- Write a legible prescription with name, age, sex, weight, diagnosis, drug's generic name, dose, route frequency and duration of treatment with other supportive drugs and treatment measures with signature and date.
- Give relevant information, instructions and warnings. (Before food or after food, need for greater intake of water, alerting or danger signals of progression of infection and when to report again etc.
- Monitor and review the therapeutic response and choose an alternative in case of intolerance, allergy or other adverse drug reactions or poor in vivo response (midcourse correction).
These steps may appear cumbersome for a busy practitioner but they re essential in the beginning of practice of whenever a new drug comes in the market of when there is significant antibiotic resistance.
Instructions to the Parents:
It is desirable to instruct parents regarding use of antibiotics as follows:
- Do not request for antibiotics for viral illnesses such as colds, cough or flu
- Remember that a viral illness may take up to two weeks to run its course. Antibiotics will not help.
- If an antibiotic is necessary for a bacterial infection ask your doctor for one that is targeted to the specific infection.
- When taking antibiotics follow all directions exactly and finish the entire prescription even if you start to feel better.
- Do not save, share or buy antibiotics for later use.
|Points to remember |
- There is a constant need to be rational while prescribing antibiotics to prevent antibiotic resistance.
- Selection of an appropriate antibiotic by a pediatrician with rational mindset depends on various factors.
Accurate clinical diagnosis based on history, physical examination an initial laboratory tests is the first step towards decision making for choosing an antibiotic.
- The clinical diagnosis then leads to consideration of the organism most commonly associated with the clinical condition, the usual pattern of susceptibility of these organisms and past experience with successful treatment regimens.
- Cultures should be obtained in potentially serious infections.
- Empiric antibiotic therapy may be initiated and then modified according to patient's response and the culture results.
- Often there are several equally safe and efficacious antibiotics in this situation, the relative cost and ease of administration of the different choices should be considered.
- Patient's immune status and exposure history.
Neonates and young infants may present with nonspecific signs of infection, making the differentiation of serious disease from mild illness difficult. In older Children Clinical diagnosis is more precise which may allow no therapy or use of a narrower spectrum antibiotic.
Immune deficiency may increase the number and types of potential infecting organisms. The severity of clinical signs and symptoms may be diminished leading to under - estimation of severity of illness.
The exposure history includes exposure from family members and classmates and unusual organisms by virtue of travel, diet or contact with animals.
The pace and seriousness of illness is an important consideration. A rapidly progressive and severe illness should be treated initially with broad-spectrum antibiotics until a specific diagnosis is made. A mildly ill outpatient should be treated with narrow spectrum antibiotics.
|Drugs of Choice in Respiratory Tract Infections|
||Drug of Choice
||Almost always viral, Rhino virus, Corona virus, RSV Parainfluenza
||Antibiotics should be avoided
||Viral - 15% case Bacterial : pneumococci, H influenza (Nontypable) M catarrhalis, Streptococci
||Amoxiclav, Cefuroxime, Cefixime, Azithromycin
||25% of H influenzae & 90% of M. Catarrhalis are resistant to Amoxicillin R (3)
|Acute Otitis Media
||Viral - 10-15% Pneumococci 28% H. influenza - 21% (non - typeable) M. Catarrhalis - 20% Streptococci - 4% Staphylococci - 3%
||High dose Amoxicillin, Amoxiclav, Cefuroxime, Ceftriaxone in resistant cases (Ref (4)
||Even after the full course fluid is persistent in 50% cases at 1 month post treatment (PT) and 20% at 2 months PT.
||Viruses Bacteria Mostly Group A streptococci
||Penicillin, Cephalexin Cephadroxil, Azithro, [Cefuroxime, Cefpodoxime in recurrent cases] Ref (5)
||Cefuroxime Short course of 5 days sufficient Ref (5)
||Always viral RSV, Parainfluenza, Adenovirus
||Antibiotics not required Oxygen, Hydration, Bronchodilators, Ribavirin in immuno compromised pt.
||Mostly viral RSV, Parainfluenza, Adenovirus, Enteroviruses
Pertussis, Salmonella, Diphtheria (rare)
|Amoxicillin, Amoxiclav, Cefuroxime, Cefixime (Third gen. Cephalosporins not reqd.)
||Antibiotics usually not required, except in recurrent or severe cases where secondary bacteria. Infection may be present.
||Mostly viral, Parainfluenza in 75% cases RSV, Adenoviruses, influenza, Measles, Mycoplasma.
||Antibiotics not reqd, for viral episode. Nebulized Adrenaline
Dexamethasone, effective. Bact Epiglottitis - Ceftriaxone, Cefotaxime.
||Organisms differ as per age of newborn: E. coli, group B Strep Klebsiella, Staph... Listeria
|| Ampi, + Genta / Amikacin... Cefotaxime + Amikacin Cefotaxime + Cloxa (If Staph)
|| Bacterial Pneumonias more common in India [61.5%] Ref (6)
(3mo - 1 yr) Staphylococci, H. Influenzae, pneumococci
|CLOX (If Staph) Cefotaxime or Ceftriaxone or Cefuroxime or Amoxiclav Cefixime in mild cases
| 1-5 yrs : Pneumococci, H. Influenzae, Staph Streptococci.
||Procaine Penicillin, Cefotaxime / Ceftriaxone Penicillin + Chloro CLOX If Staph
|5-15 years : Mycoplasma 51-74% Pneumococci Strepto Ref (7)
|| Azithro, For mycoplasma Procaine Penicillin, Cefotaxime / Ceftriaxone Penicillin+ Chloramphenicol
||Staph., Pneumococci, H. Influenza type-B
||Amikacin + Cloxacillin or Vancomycin Penicillin or Ceftriaxone Chest tube Drainage essential
||Antibiotic treatment for a periods of three to four weeks.
Abscess Aspiration with Pneumonia
|Anaerobic bacteria Fusobacter, Bacteroides Anaerobic Streptococci Staphylococci,
|Penicillin, Chloramphenicol Metronidazole, Clindamycin,
Piperacillin, CLOX + Amikacin / Vancomycin Ceftriaxone +
RATIONAL ANTIBIOTIC THERAPY OF DIARRHEA:
Antibiotics should only be used in the treatment of diarrheal disease when specifically indicated. Antibiotics are not effective in the treatment of viral enteritis, the commonest cause of acute diarrheal illness. Giardiasis should be treated when diarrheal illness becomes chronic and cysts or trophozoites of G. lamblia are found. Evidence suggests that there is generally no benefit in treating asymptomatic carriers. E. histolytica is a rare cause of diarrhea in young children. When trophozoites with ingested erythrocytes are identified in steel, treatment is warranted.
Antibiotic therapy for bacterial diarrhea remains controversial. Because most infections are self - limited and antibiotic therapy generally will not shorten the duration of illness, it has been shown to increase the duration of carriage of certain microbes. Antibiotics therapy is indicated in specific situations, such as for immunocompromised patients, as an adjunctive therapy in the treatment of cholera and in infants less than 3 months of age with positive stool cultures. Infants and children with diarrhea and signs of septicemia should be treated with parenteral antibiotics. Patients who have positive stool cultures for shigella and remain symptomatic should receive antibiotic therapy tailored to the community's antibiotic resistance pattern to that pathogen.
|How to Cite URL :|
|Jog P D.. Available From : http://www.pediatriconcall.com/fordoctor/ Conference_abstracts/report.aspx?reportid=181|