The International Physician’s Convention is Only Two Months Away!
Dates: November 1st-14th.
Travel and Hotel Coupon Codes:
Our Convention Theme: Strep Throat – A Fact of Life
Each year we take a closer look at one particular disease or ailment that affects the population at large. This year our speakers and presentations will be discussing strep throat.
If you need a primer, or at least a little refresher, on the situation, then here is a quick summary of Strep Throat:
Unfortunately, sore throats happen. You can eat all the right things, get plenty of exercise, wear a hat when it’s cold, and dry your hair when it is wet, but the truth is that sore throats will still happen. Whether it was the 5 year old at the bank who never covered his mouth when he coughed or the fact that you never washed your hands before leaving the birthday party at Chuck E. Cheese, as far as your immune system is concerned, it is only a matter of time before an infection will set in. Thankfully, a number of safe, easy, and reliable testing methods have been developed in recent years to aid clinicians in identifying these elusive agents of infection and help patients arrive at a speedy recovery.
Let us take a closer look at these microbes. We will examine the characteristics of the bacteria Streptococcus pyogenes, a microbe responsible for strep throat, and become familiar with the various diseases associated with it. We will also discover current methodologies for testing and treating these infections in a clinical setting. With any luck we will be able to arm ourselves with perhaps the most effective weapon to date, knowledge.
Signs and Symptoms
Surprisingly, it is our body’s immune response that can be attributed to many of the complications resulting from aggressive cases of strep throat, especially in cases of neglected or undertreated infections. Once the bacteria is recognized by our macrophages a cascade effect of cytokines or cellular signals are released that bring about a variety of changes. Not only are white cells called to the site of the infection whereby phagocytosis and complement fixation can take place (when bacteria are either engulfed by macrophages or tagged by protective proteins for certain death by osmotic implosion), but inflammation is also induced by those white cells that are called to serve. The distinct molecular attributes of the streptococcus bacteria, or antigens, are largely to blame. The antigens (in this case, membrane bound proteins and carbohydrates that elicit an immune response) on the surface of the bacteria kick the immune system into overdrive, producing chemical cytokines or cellular signals that induce white blood cell action and inflammation. This is what produces the characteristic soreness, swelling, and redness at the site of the infection. This not only makes swallowing difficult and painful but, lymph node glands can also begin to swell resulting in muscle ache in the neck. Fever and chills may also accompany the infection, as well as nausea and vomiting often in response to the persistent pain and discomfort.
Sources of Infection
The bacteria can be spread from person to person by droplets from the cough or sneeze of an infected person. It is also possible to pick up the infection after touching contaminated surfaces like door handles or keyboards and then touching your eyes, nose, or mouth whereby the bacteria can easily gain access to the upper respiratory tract. Strep throat caused by S. pyogenes typically effects children or anyone with a weakened immune system. The infection can clear up on its own, however in some cases; S. pyogenes infections can lead to further complications, such as glomerulonephritis, rheumatic fever, and scarlet fever, with outbreaks believed to have been first recorded as far back as the time of Hippocrates.
Behind The Scenes
Typically when clinicians test for strep throat they are looking for the bacterium Streptococcus pyogenes in order to diagnose streptococcal pharyngitis. That is not to say that other bacteria as well as viruses are not just as capable of causing upper respiratory infections, but when it comes to the characteristically red, inflamed sore throats, in this region of the world anyway, it is S. pyogenes that usually gets called in for questioning. It is a group A, Beta-hemolytic strain of bead like bacteria that can produce mild to aggressive infections. “Beta hemolytic” refers to the ability of the bacteria to completely rupture (lyse) red cells on a culture plate, demonstrating a distinct, clear zone of red cell destruction. That zone of hemolysis is a diagnostically reliable behavior that clinical professionals look for when S. pyogenes or any group A strep is suspected.
When S. pyogenes is suspected physicians will typically request that the patient have two throat swabs. One swab is for a rapid strep test, which is a quick screen for the bacterial antigen. The test utilizes an immunoassay “sandwich principle” and if that is negative than a culture is routinely run on the remaining swab.
Though there are a number of manufacturers of strep testing kits, they all tend to work off a similar “immunoassay” principle whereby a sought after antigen (in this case the S. pyogenes membrane bound carbohydrate) is bound to specific antibodies within the testing media that in conjunction with a color indicator form a unique complex that displays the presence of that antigen. The color change is then interpreted as a positive result. Since this test utilizes the high specificity of antigen-antibody binding, there is a low incidence rate of false positives. These tests are limited by sensitivity, meaning that an individual can in fact have a Strep infection that is below the detectible limits of the testing media. This is why it is a good practice for the physician to order a follow up culture for negative rapid strep screens.
Treatment and Prognosis
Antibiotics such as penicillin or amoxicillin are the usual course of treatment for bacterial sources of infection. Antibiotic treatments today have proven effective against Strep throat, with an often rapid patient recovery. However, in parts of the world where proper medical treatment is scarce S. pyogenes infections can prove to be very aggressive. A lack of antibiotic treatment in these cases also means that infected individuals remain contagious for longer periods of time during the course of their infections.
While antibiotics often prove effective in the vast majority of cases and innovative techniques like immunoassays and follow up cultures provide relatively reliable means for detecting S. pyogenes infections, we must not waiver in our vigilance of these microbes. Even something as common place as strep throat, if left unchecked can wage war on the body. Maintaining a healthy diet, reducing stress, and nurturing an active lifestyle can greatly improve your body’s ability for fighting off infections like Strep throat. It is however, in the hands of an informed and responsible public where the key to controlling the spread of such infections rests.