Strep throat
Sore throat, or pharyngitis, is diagnosed in 11 million people annually in theUnited States. Although most cases are viral, group A beta-hemolytic streptococcus causes 15—30% of the cases in children and 5—20% in adults.Cases usually occur in late winter and early spring. Strep throat is a common problem in large households, where it is a dreaded visitor. After one child picks it up, it is not long before every boy and girl in the family is lined up in the doctor’s office to get their “culture”, and sometimes adults follow too.
Strep throat, as patients know it, or streptococcal pharyngitis, which is what doctors call it, is a serious and potentially fatal disease. Caused by the group A streptococcus bacterium (Streptococcus Pyogenes) it is a form of β-hemolytic Stretococcus bacteria. It called “hemolytic” because it breaks apart red cells on a culture plate. There is no sure way of telling that a sore throat is a strep throat merely by symptoms. Coughing, nasal discharge, diarrhea, red eyes in addition to fever and sore throat are more indicative of a viral sore throat than of strep throat. Mononucleosis often has swollen nodes, enlarged tonsils, sensation of filling up quickly after eating and prolonged fever.Other kinds of Stretpococcus bacteria, and a host of other bacteria and viruses can also cause a sore throat; however, identifying the A type is important because it can cause specific complications and it must be promptly treated. These complications can be serious and include acute rheumatic fever, a disease that affects heart valves; scarlet fever, which causes a red rash and high fever; kidney disease; toxic shock and the recently described PANDAS syndrome. PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections) can cause the rapid onset of obsessive compulsive disorder and tic syndromes, such as Tourette. The connection between group A strep and PANDAS is not yet fully established. Antibiotic treatment reduces the risk of these complications. Whether antibiotic treatment of group A streptococci infection reduces the risk of lasting kidney damage is still being debated, but one recent review noted a trend showing some protection from treatment.
Is there a way to tell that a child is suffering from a strep throat without doing a culture? Strep throat can come with headache, stomach and muscle pains, nausea and vomiting and rash. However, not all sore throats are strep. Some doctors advocate the modified Centor score to determine how to treat a sore throat, even before a throat culture results is obtained. One point is given for each of the criteria:
- Absence of a cough
- Swollen and tender neck lymph glands
- Temperature > 38 °C (100 °F)
- A whitish pus or liquid or swelling on the tonsils
- Age less than 15 (a point is subtracted if age > 44 )
One point or less means no treatment and that a culture is probably not necessary (less than 10% chance of Strep A infection). Score of 2 or 3 indicates antibiotic treatment based on culture results (11-25% chance) and the score of 5 means immediate antibiotic treatment (risk of 58+%).
Many practicing pediatricians do not put much faith into Centor score. Based on their experience of seeing strep throats that have low Centor scores, they say that there is no substitute for a throat culture for a secure diagnosis of strep throat. This is also what the American Society of Infectious Diseases recommends. We can understand why this may be so when we recall that a properly done throat culture establishes the diagnosis of a strep throat with a sensitivity of 90—95%. A rapid strep test, also called RADT (rapid antigen detection tests) is less sensitive, detecting only about 70% of strep infections in the throat. On the other hand, when positive, it is as specific as the traditional throat culture, and provides immediate results. For the children in the community, who cannot return to school until after being on antibiotics for 24 hours, the rapid test can speed their return to school. The best person to recommend whether a child with a sore throat should be treated is your pediatrician.
Although untreated strep throat usually resolves by itself within a few days, treatment with antibiotics, such as penicillin or Amoxacillin, shortens the duration of the acute illness by about 16 hours. I must add that many pediatricians prefer the cephalosporin class of antibiotics (an example of a cephalosporin is Keflex). Although eradication rates conferred by cephalosporins may be superior to those achieved with penicillin, the latter remains the recommended drug of choice by the American Heart Association and the Infectious Diseases Society of America. Tylenol and pain relieving throat gargles can help decrease pain and steroids can be used in severe cases.
People who do not have symptoms should not be routinely tested with a throat culture or rapid test because a certain percentage of the population persistently “carries” the streptococcal bacteria in their throat without any harmful results. Treating these people exposes them to the risks of treatment, worry and absences from school for no demonstrable gain. Some pediatricians, however, feel that in our large families, the risk of under-treating and allowing strep to spread from one child to another, justifies repeat cultures under certain circumstances and sometimes even justifies re-treatment. This is especially a factor when a child has repeated sore throats. Interestingly, the proportion of positive carriers may be higher in our communities than in the general population. One study found that the proportion of adults with group A streptococci with and without sore throats was 6.4% and 2.4% respectively in the Orthodox Jewish group and 0.45% and 1% respectively in the general population. The proportion of children with group A streptococci with and without sore throats was 17.4% and 5.9% respectively in frum patients and 3.4% and 0% respectively in the others. These differences were not explained by the larger family size and domestic overcrowding in the Orthodox Jewish group (Br J Gen Pract. 2001 February; 51(463): 101–105).
Strep throat is a minor medical condition but one that still requires attention and appropriate care. A concerned and educated parent working together with a pediatrician can ensure that this “minor” condition remains just that, minor, and passes quickly and without complications.