Skip to main content

Oral or intravenous antibiotics for bone and heart valve infections?

Antibiotics are a miracle, killing the bacteria that might otherwise kill us. They are also dangerous, with side effects that can be fatal as well as merely annoying. They kill good bacteria as well as bad ones, disturbing the delicate balance of the bacterial communities with which we share our bodies.

Intravenous antibiotics can work quickly to forestall life threatening blood stream infections and can reach high levels in the blood and penetrate structures such as bone, eventually eradicating infections that might hide out and cause chronic infection. Oral antibiotics, however, are also very powerful and are sometimes absorbed so well that they are just as effective as intravenous (IV) ones.

Whether to use oral or IV antibiotics is based on several considerations, but we usually believe that infections on the heart valves or in the bone or joint or artificial joints require IV antibiotics. Long term treatment with IV antibiotics can be logistically difficult. Consider these two pretty common scenarios:

1. A 35 year old man, recently diagnosed with diabetes, but probably an untreated diabetic for years, comes into the clinic with a sore and smelly wound on his foot. When it is cleaned up, it is deep and you can feel bone through the hole. A diagnosis of osteomyelitis is made, since the exposed bone means there is infection there. A central intravenous catheter is placed, a procedure that costs nearly $2000.00 and he is told he will need to be on IV antibiotics for 8 weeks. His insurance won't pay for a home health nurse to administer the antibiotics so he remains in the hospital. He loses his job and his portion of the hospital bill after insurance pays their part bankrupts him and his family.

2. A young woman is hospitalized with a high fever. She has various lab abnormalities and eventually her blood cultures grow Staphylococcus aureus. She admits to using intravenous drugs sometimes. She is started on IV antibiotics which she will need to be on for 6 weeks. A central venous catheter is inserted because it is difficult to maintain an IV in her scarred veins. She can't be discharged with the central venous catheter because she will probably use it to inject her recreational drugs, thus creating a new infection. She stays in the hospital for the duration of her treatment, getting progressively bored and being emotionally explosive, straining caregivers' capacity. She develops a blood clot in her central catheter, requiring a course of anticoagulant. The final bill for her hospitalization, picked up by Medicaid, is over $100,000.

We have treated bone, joint, prosthetic joint and heart valve infections with prolonged courses of IV antibiotics for many years because the consequences of these infections not being cleared up is potentially devastating. But do we really need to continue the IV route for the whole course of treatment?

Today in the New England Journal of Medicine (NEJM) I read reports of two studies evaluating shorter courses of IV antibiotics followed by oral antibiotics.

Dr. H.-K. Li and colleagues at Oxford conducted the OVIVO trial (oral vs IV antibiotics for bone and joint infections.) Participants in the treatment group got IV antibiotics for at least 7 days (or 7 days from operation) and were then switched to an oral antibiotic which was appropriate to their infection, per cultures or clinical judgment. The control group received IV antibiotics for the whole time. They recruited over 1000 patients and found that the longer duration of intravenous antibiotics was no better, in fact might have been worse, than going to oral antibiotics after a week. The relapse rate in the oral antibiotic arm was 13.2% and for the long term IV antibiotic arm, was 14.6%. Patients received very long antibiotic courses, an average of 78 days in the IV group and 71 days in the oral antibiotic group.

Dr. Kasper Iverson from University of Copenhagen Hospital and colleagues for the POET (partial oral endocarditis treatment) study showed no superiority of prolonged antibiotics for heart valve infections.  Patients with infections involving the aortic or mitral valve, even those involving artificial valves, were no more likely to have recurrences of their valve infections or complications such as cardiac surgery, emboli or death in the 6 months after treatment.

The practice of using prolonged courses of IV antibiotics for these serious infections is strongly ingrained in us. We feel that we can be more sure of success with IV therapy. We should probably question this practice. There are too many sacrifices for our patients who are subjected to long courses of IV therapy. With an epidemic of intravenous drug abuse, obesity and diabetes, the incremental suffering and costs of extra weeks of IV therapy will continue to have increasingly negative impacts.

We should be wary of changing our practice precipitously. These studies aren't entirely representative of our situations, since the antibiotics available in Denmark are different than those available to us in the US and the populations in England and Denmark may be different in how well they take their antibiotics after discharge. It will be important to do similar studies in US hospitals. In the mean time, this does suggest that we should consider switching to oral antibiotics earlier than we have done when long term IV antibiotics may be harmful or impossible.





Comments

dfactual.com said…
i think price control will help alot
Janice Boughton said…
Long term followup shows that the patients treated with oral antibiotics did not have more relapses. In fact, it looks like they do somewhat better!

https://www.nejm.org/doi/full/10.1056/NEJMc1902096?query=TOC

Popular posts from this blog

How to make your own ultrasound gel (which is also sterile and edible and environmentally friendly) **UPDATED--NEW RECIPE**

I have been doing lots of bedside ultrasound lately and realized how useful it would be in areas far off the beaten track like Haiti, for instance. With a bedside ultrasound (mine fits in my pocket) I could diagnose heart disease, kidney and gallbladder problems, various cancers as well as lung and intestinal diseases. Then I realized that I would have to take a whole bunch of ultrasound gel with me which would mean that I would have to check luggage, which is a real pain when traveling light to a place where luggage disappears. I heard that you can use water, or spit, in a pinch, or even lotion, though oil based coupling media apparently break down the surface of the transducer. Or, of course, you can just use ultrasound gel. Ultrasound requires an aqueous interface between the transducer and the skin or else all you see is black. Ultrasound gel is a clear goo, looks like hair gel or aloe vera, and is made by several companies out of various combinations of propylene glycol, glyce...

Ivermectin for Covid--Does it work? We don't know.

  Lately there has been quite a heated controversy about whether to use ivermectin for Covid-19.  The FDA , a US federal agency responsible for providing unbiased information to protect people from harmful drugs, foods, even tobacco products, has said that there is not good evidence of ivermectin's safety and effectiveness in treating Covid 19, and that just about sums up what we truly know about ivermectin in the context of Covid. The CDC, Centers for Disease Control, a branch of the department of Health and Human Services, tasked with preventing and treating disease and injury, also recently warned  people not to use ivermectin to treat Covid outside of actual clinical trials. Certain highly qualified physicians, including ones who practice critical care medicine and manage many patients with severe Covid infections in the intensive care unit vocally support the use of ivermectin to treat Covid and have published dosing schedules and reviews of the literature supporting...

Actinic Keratoses and Carac (fluorouracil) cream: why is this so expensive?

First, a disclaimer: I don't know why Carac (0.5% flourouracil cream) is so expensive. I will speculate, though, at the very end of this blog. Sun and the skin: what happens If a person reaches a certain age, has very little pigment in her skin, and has spent lots of time in the sun, bad stuff happens. The ultraviolet radiation of the sun does all kinds of great things: it makes us happy, causes us to synthesize vitamin D which strengthens our bones and it gives us this healthy glow until we get old and wrinkled and leathery. And even that can be charming. The skin cells put up with this remarkably well for a long time, partly aided by melanin pigment which absorbs the radiation, which is why we tan and freckle, if we are fair skinned. Eventually, though, we absorb enough radiation that it injures the skin and produces cells which multiply oddly. It also damages the skin's elasticity which creates wrinkles. The cells which reproduce in odd ways peel, creating dry skin or...