Not all strep is created equal

A common source of confusion for patients is the inter-relation between the various species of streptococcus.  The genus streptococcus delineates a type of round bacteria in chains that stains as black on a special bacterial gram stain.  The various species of streptococcus vary dramatically in their degree of danger, in the places in the body in which they reside and in their antibiotic sensitivity.  For example, Streptococcus pneumoniae is related to Streptococcus pyogenes the same way that Canis lupus familiaris (the domestic dog) is related to Canis mesomelas (the black footed jackal http://en.wikipedia.org/wiki/Black-backed_Jackal)

Streptococcus (aka strep) pyogenes typicall lives in the throat and causes strep throat.  It can infect the skin and cause impetigo or cellulits or rarely and abscess.  It is almost always sensitive to beta lactam antibiotics including penicillin.

Strep pneumoniae (aka pneumococcus) frequently causes middle ear and sinus infections as well as pneumonias and infections between the lining of the lung and chest wall.  It is a common cause of meningitis as well.  Pneumococcus is frequently resistent to usual doses of amoxicillin requiring high doses of the drug or vancomycin to treat the meningitis.

Group B streptococcus lives harmlessly in the genitourinary tract of women of child bearing age.  If transmitted to a newborn it causes blood and brain infections.  Some people think that this was responsible for the death of Elvis' twin, Jesse Garon Prelsey. 

Group D strep aka strep viridans lives in the mouth.  It is responsible for many dental cavities but is generally harmless unless you have a bad heart valve or hardware inserted into the body surgically.  In those cases it can colonize the heart or hardware resulting in serious illness.

I hope that this has been enlightening.

Kevin M. Windisch MD, FAAP
Sparks Pediatric and Adolescent Medicine
974 Roberta Lane #101 B
Sparks NV 89431
775-359-7111

Strep Throat Rx

A little known fact is that medication for strep does very little to eliminate the pain of strep.  Treated patients get better only one day earlier than untreated patients.

So, why do we treat???

We treat in order to prevent rheumatic heart damage.  That complication only comes on 10-14 days after initial infection so we have time to wait for culture results to come back.

I hope that this has been educational.

Kevin M. Windisch MD, FAAP
Sparks Pediatric and Adolescent Medicine
(775) 359-7111
975 Roberta Lane, suite 101 B, Sparks, NV 89431.
www.facebook.com/sparkspeds.nv