A team from John H. Stroger Hospital (the new location of the iconic Cook County Hospital, public hospital for downtown Chicago) and from the Alliance for the Prudent Use of Antibiotics at Tufts University (headed by Dr. Stuart Levy, dean of antibiotic resistance scholarship in the US) has analyzed the direct and distributed costs of resistant infections, and their results are stunning. They took a random sample of patients seen at the hospital, sorted out a subgroup that suffered from resistant infections, and computed the costs that those infections imposed: in medical costs, increased length of stay, and excess deaths. Those sort of calculations have been done before at other institutions (cf. for instance the excellent work of Susan Cosgrove of Johns Hopkins), but what makes this Chicago study striking is an additional layer of analysis that computes the "social cost" to the families of those infected.
In the study's words:
In a sample of 1391 patients, 188 (13.5%) had [antibiotic-resistant infections]. The medical costs attributable to ARI ranged from $18,588 to $29,069 per patient in the sensitivity analysis. Excess duration of hospital stay was 6.4–12.7 days, and attributable mortality was 6.5%. The societal costs were $10.7–$15.0 million.(Just to underline: These are almost certainly underestimates of the current problem and its current costs — because to get very solid data, the Stroger team went back in their database to patients who were treated in 2000. That's before the emergence and dominance of CA-MRSA USA300 nationwide, and its subsequent movement into hospitals. Since 2000, the MRSA epidemic has gotten worse.)
An accompanying editorial takes the next step in logic, stressing that if we're not going to work to reduce ARIs because it is good medicine to do so, we should do it because it is critically cost-saving:
...[T]he findings of Roberts et al  are significant, making a strong case for both the medical and financial benefits of reducing antimicrobial resistance. This is an important and timely question, considering the national focus on the prevention of health care–acquired infections, a significant proportion of which are caused by antimicrobial-resistant organisms, and the call for institutions to develop antimicrobial stewardship programs. These data should help inform decisions regarding the structure and implementation of health care initiatives designed to improve patient care while controlling unnecessary costs.The cite for the study is: Rebecca R. Roberts, Bala Hota, Ibrar Ahmad et al. Hospital and Societal Costs of Antimicrobial‐Resistant Infections in a Chicago Teaching Hospital: Implications for Antibiotic Stewardship. Clinical Infectious Diseases 2009 49:8, 1175-1184.