Hidoc Bulletin

“Having infectious disease? Get some antibiotics”-This is what basically the common  individuals think about managing infectious diseases. Unfortunately, this little knowledge can turn into a dreadful decision as per the current trend of antibiotic resistance. The healthcare providers should properly guide the patients regarding the dosage of  antibiotics while deciding to initiate an antimicrobial therapy. Indiscriminate use of antibiotics is associated with drug resistance which may lead to costly treatments. Thus, 
while recommending antibiotics it is important to a number of factors: 

 Diagnosis:

The most important part of understanding which antibiotics would be a better recommendation for the patients is by properly diagnosing the causative agent of the infection. During the initial evaluation, performing a gram stain helps in presumptive diagnosis of the causative organism which eventually helps in determining the antibiotic 
selection. Further, considering the antibiotic susceptibility patterns would also help in the same. Susceptibility testing facilitates the rational selection of antimicrobial agents for targeted therapy and should be performed on all positive bacterial  cultures. Moreover, rapid diagnostic testing which includes polymerase chain reaction (PCR) and antigen detection can also help in providing early confirmation of the infectious etiologic agent. 

Treatment:

While choosing the treatment approaches, the following factors are considered: 

1. In order to select empiric therapy, it is important to detect the pathogens and identify the antibiotic with the narrowest spectrum. Therapy can be modified according to the patient’s clinical course and culture results. Most importantly, the drug allergies of the patients need to be considered before prescribing the antibiotics. 

2. Basically, in acute cases the therapy is initiated immediately after appropriate cultures are obtained. However, in case the patient is stable, the selection for therapy is delayed in order to understand the appropriate targeted therpy based on initial testing. This will 
help in avoiding the use of unnecessary drugs. Urgent therapy is required in febrile patients who are neutropenic or asplenic and also in cases of sepsis, meningitis, and rapidly progressive anaerobic or necrotizing infections. 

Route of Administration: 

Intravenous drugs are given in case the patients are having serious infections. Otherwise, intramuscular (IM) or oral (PO) therapy is given if adequate drug concentrations can be achieved at the site of infection. 

Type of therapy and its outcomes:

Bactericidal therapy is preferred in the cases of bacterial infections like endocarditis, meningitis, and osteomyelitis which have led to immunologic compromise or life-threatening infections. Renal and hepatic functions need to be considered to determine the dosing regimens of the drugs in order to understand the efficacy of the drug or the adverse effects or if there is any chance of drug interaction. Further safety 
profile needs to be considered while prescribing a pregnant or postpartum patient. 

Duration of therapy:

The duration of treatment depends on the nature and severity of the infection like in uncomplicated infections it can be continued for a minimum of 72 hours whereas, in severe cases like endocarditis, septic arthritis, osteomyelitis etc require prolonged treatment.