LATE OUTCOMES IN PATIENTS WITH OSTEOMYELITIS: RETROSPECTIVE ANALYSIS OF THE BONE AND JOINT INFECTION

ORGANIZATION (BAJIO) GROUPAbhinav Ohri, MBBS,1 Cheick Mariko,CRC,2 Julie Harting, PharmD,2,3 Robert Kelley, PhD,2 Adam Hicks, DPM,4 Timothy Wiemken ,PhD2

Raul Nakamatsu, MD,2 Diana Christensen, MD,2 Julio Ramirez, MD.2 1 Internal Medicine, University of Louisville School of Medicine; 2 Med-Infectious Diseases, University of Louisville School Of Medicine; 3

Sullivan University, College of Pharmacy; 4 Department of Podiatry, University of Louisville school of Medicine.

Background: Data are lacking regarding the late outcomes in patients with osteomyelitis. The objective of this study was to evaluate the outcomes of patients with osteomyelitis after initial antibiotic treatment, 6 months and 1 year after therapy.

Methods: This is a retrospective study of patients at the University of Louisville Hospital and the VA Hospital in Louisville. Inclusion criteria were patients with the diagnosis of osteomyelitis that completed an initial IV antibiotic therapy for 4-6 weeks. Outcomes were evaluated at, the end of initial IV therapy, at 6 months and at 1 year. Clinical success was defined as clinical improvement, decrease in ESR and CRP.

Results: 56 patients were reviewed. The mean age was 54 years with 66% males. Etiologies were methicillin resistant Staphylococcus aureus, methicillin sensitive Staphylococcus aureus, Streptococcus group B, Enterococcus faecalis, and Pseudomonas. The average duration of antibiotic treatment was 31 days with surgical intervention in 88% of the patients. Initial outcomes showed success in 98% of the patients, failure in 2% and loss of follow up in 18%. Late outcomes evaluated at 4-7 months period showed: success in 85% and failure in 15%. Outcomes at 8-12 months were evaluated in 41%, showing 87% success and 13% failure. The loss of follow up at 8-12 months was 59%.

Conclusion: The study revealed that outcomes at the end of the initial antimicrobial therapy were successful in 98%. A great majority of our cases had surgical intervention along with the antibiotic therapy. For the late outcomes the success rate was 85-87%.

• Data are lacking regarding late outcomes in patients with osteomyelitis.

• The duration and route of antibiotic therapy is based on expert opinions.1,3,

• The objective of this study was to identify the late outcomes in patients with Osteomyelitis or Prosthetic Joint Infections.

• Current guidelines recommend surgical debridement whenever possible along with antibiotic therapy.2,3

ABSTRACT

98%

2%

Figure 4: Initial Outcomes

SuccessFailure

85%

15%

Figure 5: 4-7 Months Outcomes

Success

Failure

87%

13%

Figure 6: 8-12 Months Outcomes

Success

Failure

37%

50%

13%

Figure 1: Sites of infection

Foot Osteomyelitis

Non foot Os-teomyelitis

Prosthetic Joint In-fections

Hyper

tensi

on

Diabet

es

Hyper

lipid

emia

Tobacco

Use

Neuro

pathy

0%

20%

40%

60%

80% 75%

59% 54% 50%

34%

Figure 2: Comorbidities

• This was a retrospective cohort study of adult patients at the University of Louisville Hospital and the Veterans Affair Medical Center in Louisville.

• All patients from November 2010 to July 2013 were evaluated. Inclusion criteria was the diagnosis of osteomyelitis confirmed with positive imaging and/or positive bone culture or pathology or Prosthetic Joint infections that completed an initial antibiotic therapy for 4-6 weeks.

• Microbiological diagnosis was confirmed with positive bone culture, deep tissue culture, or blood culture.

• Clinical Success was defined as clinical improvement and decrease in ESR and CRP.

• Outcomes were evaluated at the at the of the initial intravenous antibiotic therapy and during 6 months and 1 year follow up.

• A total of 56 patients with the diagnosis of osteomyelitis and Prosthetic Joint Infections were reviewed.

• The mean patient age was 54 years with 37/56 (66%) males and 19/56(34%) females.

• The site of infections are represented in Figure 1 below.

• For the Non foot osteomyelitis the most common sites were tibia/fibula 6/56(11%), Vertebral 6/56(11%), femur 5/56(9%), mandible 4/56(7%).

• For the Prosthetic Joint Infections, the most common sites were Knee 4/56(7%) and Hip 2/56(7%).

• The major comorbidities are listed in Figure 2 below.

• In the 56 patients, 186 micro-organisms were identified, indicating some infections were poly microbial. The most common etiologies are shown in Figure 3.

• Antibiotic therapy was guided by the organisms identified on the cultures and sensitivities.

• The average duration of intravenous antibiotic treatment was 31 days.

• A vast majority of our patients 49/56(88%) underwent surgical debridement along with antibiotic therapy.

• Initial outcomes (at the end of the initial antibiotic therapy) and late outcomes at 4-7 months and 8-12 months after induction therapy are depicted in Figures 4, 5 and 6 respectively.

• Outcomes at the end of initial antimicrobial therapy were clinical success in 98% of the cases.

• Late Outcomes at 4-7 months and 8-12 months after the induction therapy demonstrated success in 85% and 87% patients respectively.

• Best results were seen when antibiotic therapy was combined with surgical intervention.

• A significant number of our patients were lost to follow up and their outcomes remained uncertain. Emphasis must be made to improve long term follow up.

• 1. Lazzarini L, Lipsky BA, Mader JT. Antibiotic treatment of osteomyelitis: what we have learned from 30 years of clinical trials? Int J Infect Dis 2005;9:127-38

• 2. Rod-Fleury T, Dunkel N, Assal M, et al. Duration of post surgical antibiotic therapy for adult chronic osteomyelitis: a single center experience.

• 3. Uckay I, Jugun K. Chronic Osteomyelitis. Curr Infect Dis Rep(2012);14:566-575.

INTRODUCTION

METHODS

RESULTS

CONCLUSIONS

Methicillin Resistant Staphylococcus aureus

Methicillin Sensitive Staphylococcus aureus

Group B Streptococcus

Enterococcus faecalis

Pseudomonas aeruginosa

0% 10% 20% 30% 40% 50% 60% 70%

59%

23%

23%

21%

20%

Figure 3: Causative Organisms

REFERENCES