This article was originally written by Nyx Chong, and was edited by Irsyad Ramthan
Back in July, there was a lot of media attention on a study published in the British Medical Journal (BMJ) that calls into question the need to finish the course of antibiotics that a doctor prescribes to you. However, most media coverage, perhaps in an attempt to simplify the issue for a mass audience, have conflated a few topics when it comes to antibiotic distribution and use. Additionally, they have not picked out the differentiation in what kind of bacteria resistance the BMJ article was concerned with.
When patients decide to discontinue a medication without any knowledge of disease progression or pathology, it may ultimately lead to more harm than good. Discontinuing an antibiotic early, while still carrying a pathogen (AKA infectious bug) may lead to more disease resistant strains. The equivalent to early discontinuation of antibiotics is analogous to discontinuing blood pressure medications in a patient with heart problems and high blood pressure. In the same way the effects of a blood pressure drug reduces unseen factors contributing to a heart attack, antibiotics help to fend off unseen pathogens in an infected person from inducing a more serious problem such as sepsis.
The BMJ article’s main concern seemed to be the rise of antibiotic resistance in endogenous flora that might predispose these bacteria to opportunistic infections of the host in the future, thus making it difficult to treat infections.
What does this mean?
The human body is a host for organisms. These organisms such as E.coli in our stomach or Staphylococcus aureus on our skin often do not cause infection. In fact, we are unable to do without certain species of gut bacteria. Probiotics promotes the growth of ‘good/ healthy’ bacteria in our gut after episodes of traveller’s diarrhea. The problem with these endogenous flora (i.e. bacteria naturally found on a human body) is that every so often, when a species enters a space where it doesn’t belong (e.g. Staphylococcus aureus enters the bloodstream), it may cause bodily upset leading to symptoms such as fever and chills. This, too, would be deemed as an infection.
In healthier times, this misplacement of endogenous flora does not happen often. However, when one’s immune system is compromised, opportunistic infection by endogenous flora may happen. Alternatively, the overuse of antibiotic to treat an invasive species might have cleared all our endogenous flora leading to upset in the ecosystem of bacteria that dwells in our gut. In this scenario, one endogenous species colonizes more than it should leading to an infection. Hence we can see here the terms ‘infection’ and ‘bacteria’ very loosely describe a whole array of species and origin/ causation of infection. To use these terms vaguely can cause unnecessary panic.
The BMJ article is concerned with prolonged use of antibiotics because drugs often end up targeting helpful strains of bacteria, in addition to the pathogenic ones, due to certain non-specific effects. Endogenous flora is exposed to the same antibiotic causing resistance to breed. When these resistant endogenous flora eventually become pathogenic (i.e. turn from helpful bacteria to infectious bacteria), the problem of antibiotic resistance prevents easy treatment of the bacteria as compared to the same strain which is new to an antibiotic.
Therefore, the BMJ article’s suggested solution is to treat invasive infections for the shortest time possible. This will thus prevent endogenous flora from becoming resistant from unreasonably long exposure to antibiotics. However, due to the deficit of clinical evidence of minimum time for use of antibiotics in a given treatment, the authors of BMJ question the duration of certain antibiotic therapies (the example cited being 7-14 days) used in current practice. They are suggesting a need to reevaluate this time frame of treatment. Ideally, the course of bacteria should be long enough to treat/eradicate the pathogenic bacteria but short enough to prevent resistant strains from developing in our endogenous flora.
So where do we go from here?
1) The discontinuation of antibiotics suggested by the BMJ does not suggest discontinuation of all antibiotics for all kinds of bacteria and infection. In an event where the pathogen has been successfully treated, it is reasonable to discontinue antibiotics.
HOWEVER, in the event where eradication remains unknown, it might be safer to finish the course of antibiotics.
2) In order to know the ideal duration of treatment for an offending species, more research and evidence is required to suggest an optimal time frame. The early discontinuation of antibiotics is complacent and may lead to development of resistance in both endogenous flora and invading pathogen.
The original paper can be found here: http://www.bmj.com/content/358/bmj.j3418
Nyx Chong graduated from the National University of Singapore with BSc, (Hons) in pharmacy, class of 2017; She is currently undergoing her pre-registration training to be a qualified pharmacist.