ABSSSI: Incidence and Rates of Readmittance

Experts provide an overview of the incidence of acute bacterial skin and skin structure infections (ABSSSIs), including logistics for admittance and readmittance.

Tom Lodise, PharmD, PhD: In terms of prevalence of skin and soft tissue infections, it’s estimated there are about 6.5 million patients who present to doctors’ offices with a skin infection. These are primarily your simple cellulitis, those that can be largely managed with topical antibiotics. For some of the more severe or complicated infections involving the skin, about 3.5 million Americans present to the ED [emergency department]. Of these individuals, we have somewhere between 600,000 and 800,000 admissions. When these patients are admitted, on the average they stay there 5 days. However, about 25% of them are there for 8 days or more.

In terms of cost, it’s somewhere between $5000 and $10,000, but a lot of that’s driven by how long the patient is in the hospital and the intensity of their care. But again, when we think about skin infections, mostly the hospital costs are due to just room and board, a hotel cost. Another thing to consider with skin infections is readmissions. What we found is 30-day readmissions are somewhere between 15% and 20%, and it’s estimated that 5% to 10% of these are infection related. So when we think about these readmissions, these are patients who failed their initial therapy and have progression of infection or new infection or more extensive involvement of the original infection.

Joe Reilly, PharmD, BS, BCGP: And as far as admitting diagnosis in the United States, skin and soft tissue infections or ABSSSI is in the top 10 primary admitting diagnosis in the country. I think it’s the seventh-leading now, the seventh-most-common diagnosis for admission. And once they’re admitted, as we said before, it’s not specifically based on the fact that they’re unstable or they require special therapy; there are just a lot of factors to look at as to why we’re admitting these patients. The best thing would be is if everybody would just take their antibiotics, and there wouldn’t be much of an issue. If we can ensure that everybody had a full course of antibiotic therapy, whether that’s 7, 10, or 14 days or longer, we can ensure that they have those antibiotics in them. I think outcomes would be a lot better, and the readmission rates or the reinfection rates would probably be lower.

Tom Lodise, PharmD, PhD: And I think Joe brings up a good point. It’s a seventh- or eighth-leading admitting diagnosis in the United States; that’s 2% of all admissions. So for 1 in 50 people who get admitted into the hospital, it’s likely due to skin infection. So I think in infectious disease, we’re really focused on resistant gram-negative infections, those with high mortality, and I think it’s probably wise from a stewardship standpoint to start looking at skin infections with high frequency that are associated with considerable health care costs, much of which can be avoided by the initial site-of-care decision or a better initial site-of-care decision.

Joe Reilly, PharmD, BS, BCGP: That’s often a topic that’s overlooked in hospitals. I think a lot of even clinical pharmacists are unaware what a drain the skin infections are on the hospital costs. It doesn’t seem as glamorous as endocarditis or bacteremia or other gram-negative multidrug-resistant infections. But if you really take a look at it, skin infections affect a lot of hospitals. It’s a money loser for many hospitals, and it’s a recurrent theme and something that should be addressed. Because the methods that we have now, the system in place or the treatment paradigm just doesn’t seem to work that well, or it could certainly be improved. When you have to rely on patients to take their antibiotics in the outpatient setting in order to finish their course of therapy, the results aren’t going to be good in general.

When patients are in a hospital for longer than you would expect or longer than you want, there’s no specific penalty imposed on the hospital by CMS. I guess the penalty would be financial losses. So if a patient certainly needs 10 days of antibiotic therapy and you’re certain that they’re not going to take antibiotics in the outpatient setting, you could just think, “Well, I’ll leave them here, and we’ll give them 10 days to ensure it.” But that would wind up resulting in significant losses financially.

As I mentioned before, these patients, in order to even break even based on reimbursement for a skin infection for that DRG [diagnosis-related group] 603 or even 602, if you’re getting $5000 per admission, that means they have to be gone in 3 days. So there’s no specific penalty imposed. CMS can impose penalties for readmissions on hospitals for certain diseases such as myocardial infarction, pneumonia, and CHF [congestive heart failure] or COPD [chronic obstructive pulmonary disease]. And they do that by decreasing reimbursement in their payments. Now, they don’t do it right now for skin infections. However, they collect data on those readmissions and certainly could be something in the future that we may see penalties imposed on. I don’t know your feelings on that, Tom, whether it will happen.

Tom Lodise, PharmD, PhD: As of right now, it’s not on what I call the naughty list, the naughty readmission list. But again, as we mention through today, skin infections are 2% of all hospital admissions. A large proportion do get readmitted. Many of those are infection related, and it’s costly at a point where cost exceeds reimbursement. So as of now, it’s not on the list, but there are a lot of factors pointing toward it. It may ultimately be on the list. I think through our discussion, I think there are clear opportunities to improve the management of these patients.

Joe Reilly, PharmD, BS, BCGP: Yes. When we started taking a look at some of our patients at our institution, the population certainly has an effect on how often you have readmissions or reinfection rates. We’ve had patients come in 5 or 6 times in a 6-month period with the same cellulitis. So if we can lock them up in a room and ensure that they got 10 days of antibiotics, I’m sure it would get better. The problem is that we’re not going to do that. It’s often the approach is shortsighted with costs. We look at the immediate cost in front of us and not the bigger picture. The most expensive therapy is the one that doesn’t work.