Home PageStreptococcal Pharyngitis (Strep Throat)
By: Keri Hochstetler
strep_bacteria.gif
Copyright: ajp.amjpathol.org

Abstract

Streptococcal Pharyngitis, also known as strep throat, is an upper respiratory infection caused by Group A Streptococci (GAS). Strep throat can be detected by enzyme immunoassay (EIA) tests, which are sensitive and easy to read. The common symptoms of strep throat are fever of 101 degrees Fahrenheit, local inflammation of the throat, enlarged lymph nodes, and possible tonsillitis or ear infection. Respiratory secretions most commonly transmit strep throat, so it is easily spread through the air if you are in close proximity with some one who has the strep infection. Strep throat is sometimes misdiagnosed as mononucleosis because they share common symptoms such as sore throat, inflammation, and swollen lymph nodes, but their main difference is that strep throat is an infection and mono is a virus.


Introduction
I chose the topic of strep throat because it is such a common infection, yet i did not know much about it. I have personally had strep throat and the majority of people have also had strep throat at least once in their life. Strep throat is more common in children, which interests me because i want to be a pediatric nurse some day. I have also had friends that have had mono or strep, but have been misdiagnosed. This happens all to common because they have similar symptoms. It is important that people get diagnosed correctly because both mono and strep have different levels of severity and they are also treated differently. One of the most interesting things I learned was that strep throat is caused by Group A Streptococci, which also causes skin infections. I did not know that throat infections and skin infections were related through this bacterium.


Discussion
What is Strep Throat?
Strep Throat is an upper respiratory infection caused by Group A Streptococci (GAS). This bacteria is a gram-positive bacterial group that consists of streptococcus pyogens. (same bacteria that causes skin and soft tissue infections such as impetigo, erysipelas, and acute bacterial endocarditis) Group A streptococci can cause a range of infections from mild sore throats and skin infections to life threatening invasive diseases. Infections caused by the GAS bacteria are usually treatable with antibiotics.(Director of Health Promotions and Education, 2005) GAS bacteria are pathogenically enhanced by their resistance to phagocytosis. They are also sensitive to penicillin, but some resistance to erythromycin has appeared. These bacteria are also able to produce special enzymes like streptokinases, which are lyse fibrin clots and streptolysins, which are cytoxoxic to tissue cells, red blood cells, and protective leukocytes. (Tortora, 714)

How is Step Throat detected?
In the early 1980's, rapid antigen detection tests were capable of detecting GAS directly on throat swabs. The first rapid test used late indirect agglutination methods. Indirect agglutination is when you allow the particles of a reagent to precipitate in the bottom of a container and then angle that container so that you can examine the occurrence of an immunoreaction based on the values of the measured lengths of the precipitation pattern. The indirect agglutination method has now been replaced with enzyme immunoassay (EIA) tests that are more sensitive and easier to read. The EIA test is used to detect the presence of an antigen in a sample. In this process an unknown amount of antigen is fixed to a surface and then an antibody is washed over the surface so the antibody can bind to the antigen. Currently there are a wide variety of rapid tests available to evaluate cases of pharyngitis, including throat cultures which are most commonly used by doctors today. (Tortora, 714)
EIA_test.jpg
Copyright: www.wellsphere.com

Symptoms of Strep Throat. (Health Link, 2009 & Tortora, 714 & WebMD, 2008)
~local inflammation of the throat ( tonsils, pharynx, and larynx)
~fever over 101 degrees Fahrenheit
~tonsillitis can occur
~lymph nodes in neck become enlarge and tender
~possible infection of the middle ear
~rash
~white or yellow spots on the back of the throat
~sudden, severe sore throat

How is Strep Throat transmitted?
Anybody can get strep throat, but it is most common in school age children. The bacteria Group A streptococci tend to be present in the nose and throat area, so actions like actions like sneezing, coughing, and shaking hands are the most common sources of spreading the strep infection. Strep Throat is most commonly transmitted through respiratory secretions or exchange of saliva. There have been epidemics of streptococcal pharyngitis spread by unpasteurized milk, but this is not as common. (Kids Health, 2009)

Why is Strep Throat commonly misdiagnosed?
Many people that get tested for strep throat are sometimes misdiagnosed with another infection or virus. Mono, for example, is a virus that has common symptoms to strep throat. Mono and strep throat both have the symptoms of sore throat, inflamed tonsils, and swollen lymh nodes. Unlike strep throat, mono is a virus meaning antibiotic therapy is an ineffective way to treat it. (WebMD, 2008)

Prevention and Treatment
Strep Throat can be prevented by avoiding contact with anyone who has a strep infection. Practice basic sanitary techniques such as washing your hands and not sharing drinks or utensils. You can also avoid coming in contact with people who are couching or sneezing because strep throat is easily transmitted through tiny droplets of mucus. Strep Throat can be treated by taking medications such as penicillin or amoxicillin. Medication is used to relieve the symptoms of strep throat only if given within 48 to 72 hours of when symptoms first began. Strep Throat will usually go away within 3 to 7 days with or without treatment. (Mayo Foundation of Medical Education and Research, 2008)


Literature Cited

"Group A Streptococcus."Directors of Health Promotion and Education2005 Web.14 May 2009. <http://www.dhpe.org/infect/strepa.html>.

"Strep Throat." Kids Health from Nemours 2009 1-3. Web.13 May 2009.<http://kidshealth.org/parent/infections/lung/strep_throat.html

"Strep Throat." Mayo Foundation for Medical Education and Research 2008 1-5. Web.14 May 2009. <http://www.mayoclinic.com/health/strep-throat/DS00260>.

"Strep Throat." WebMD 2008 1-2. Web.14 May 2009. <http://www.webmd.com/a-to-z-guides/strep-throat-topic-overview>.

"Streptococcal Pharyngitis." Health Link: Medical college of Wisconsin 2009 Web.13 May 2009.<http://healthlink.mcw.edu/article/955152510.html>.

Tortora, Gerard J., Berdell R. Funke, and Christine L. Case. Microbiology An Introduction with CDROM. Boston: Benjamin-Cummings Company, 2006.