Gettysburg Medical News
The Clinical View
by P.E. Hoffsten, MD
25 April 2007

 “Doc, Just Give Me a Shot of Penicillin!”

            I cannot count the number of times a patient has come to the clinic with some sort of infection and naively asked for a “shot of penicillin”.  In 2007 it is just not something that any longer has a useful effect.  A mother came to the clinic on a Saturday morning with this request for herself and her two daughters.  The outcome of this visit was not quite what she expected.

            The story begins with the mother seeking medical attention in another community 10 days before for concern about a “kidney infection”.  There were no blood tests or urine tests done as the doctor at the out-of-town clinic simply listened to her complaint and gave her an antibiotic called ampicillin.  This is an appropriate antibiotic if she really had a “kidney infection”.  In fact, she had a bladder tumor causing her symptoms as was demonstrated by her evaluation done over the next several days.  But, this Saturday morning she had the same symptoms she had ten days ago and now she had diarrhea so bad she was threatened just coming to the clinic.  She said she just knew “those pills do not work for her” and she needed a shot of penicillin.  In fact, in addition to her bladder tumor, she now had an intestinal infection called C. diff (for Clostridium difficile) caused by the inappropriate antibiotic she had received 10 days before.  Now she needed a different antibiotic called metronidazole to treat her intestinal infection.  But she did not need a penicillin shot.

            The first daughter was 21-years old, home from college on spring break.  She went to school in Florida and had been to a picnic two days before, where the food had been warm all day before the picnic in the early evening.  The daughter became ill with cramping abdominal pain and diarrhea while on the airplane on the way home.  She appeared very ill this Saturday morning with mom saying the daughter “just needed a penicillin shot” and everything would be alright.  It turned out the daughter had severe Staphylococcal food poisoning and was very dehydrated.  The daughter wound up in the hospital on IV fluids for two days while the Staphylococcal toxins passed on through the bowel.  But the daughter did not need a penicillin shot.

            The second daughter was an 18-year-old high school student with diarrhea, a high fever, cramping abdominal pain and no tolerance for illness.  She wanted something done NOW!!  This daughter had places to go and people to meet and a date tonight.  And mom just knew this girl only needed a penicillin shot and everything would be alright.  This girl, too, was severely dehydrated and wound up in the hospital much to her disliking.  Unfortunately, the cultures to determine the cause for her illness did not return for three days, when they finally grew bacteria called shigella.  This bacterium is sensitive to an antibiotic called ciprofloxacin which was then started and the illness resolved in two days.  This was 5 days too late for this daughter who was very unhappy at the inconvenience of her illness.  But she did not need a penicillin shot.

            So here were three different patients with similar presentations but very different illnesses.  Infectious diseases are still the most common illnesses that bring patients to medical attention.  These illnesses can never be taken lightly as missing a major infection can be disastrous.  Yet rarely is an “infectious disease specialist” available.  There are only six such specialists in all of South Dakota.  So infectious diseases are dealt with by the primary health care providers in your local clinics.  And it is not easy.

            While penicillin was one of our first available antibiotics discovered in 1938, the bacteria in 2007 have figured penicillin out.  It is rarely used alone except for “Strep throats” for which it is still the drug of choice.  And penicillin pills work just as fast and as well as a shot unless the person is vomiting and cannot keep the pills down.  So a shot of penicillin is rarely useful.

            At the same time penicillin was discovered, sulfa drugs were found to be a useful antibiotic.  Sulfa is still used today for urinary tract infections especially in men because sulfa penetrates the prostate gland very well.  But many people are allergic to sulfa thus limiting its use.

            Tetracyclines were discovered in the 1950’s and are still used for acne, urinary tract infections, and several other infections such as rocky mountain spotted fever.  But, like penicillin antibiotic resistance has developed over the years and tetracycline antibiotics are infrequently used in 2007.  They cause sun sensitivity and can be associated with severe sun burns.

            In the 1960’s a new class of antibiotics called cephalothins came on the market and are still used extensively today.  There are 1^st, 2^nd, 3^rd, and even 4^th generation cephalothins as research continues to improve the antibiotic molecule to overcome bacterial resistance that continues to evolve.  There are no fewer than 30 different cephalothin products on the market.

            In the late 1960’s came the macrolides initially sold as erythromycin.  This antibiotic was nasty causing abdominal pain and nausea.  But it is still used today to treat Legionnaire’s Disease.  The antibiotic “Zithromax” (azithromycin) is one of the most common antibiotics used today for upper respiratory tract infections because it is effective with very few side effects.

            In 1987 ciprofloxacin was brought onto the market to be followed by many other “quinolone” antibiotics.  The most commonly used pneumonia antibiotic today is “Levaquin” (levofloxacin).  The quinolone family comprises the most useful broad spectrum antibiotic family today.

             In addition to the bacterial antibiotic families described above, there are many other specialty antibiotics to cover “resistant staph”, “resistant strep”, and a host of other difficult to treat infections.  And then there are antibiotics to treat viral infections such as HIV, Herpes, CMV, etc.  There are antifungal agents and even special antibiotics to treat parasites such as worms (yuck!!).  I do not know how we keep track of them all. 

            This weekend I am covering the hospital in Gettysburg where a lady was admitted with a high fever and septicemia.  Her initial antibiotics included Rocephin and azithromycin, a logical reasonable first choice.  But her fever did not come down.  On the second hospital day vancomycin was added when her blood cultures grew a “gram (+) coccus which often means a resistant Staph.  Then on the third hospital day the lab called saying the bacterium in her blood was unusual.  It was an Enterococcus resistant to all three antibiotics used.  Finally the right antibiotic could be given. 

            This infectious disease stuff and the right antibiotic is never easy.  Please, don’t come to the clinic thinking you just need a penicillin shot.