Predicting the pathogen of diabetic toe osteomyelitis by two consecutive ulcer cultures with bone contact

Abstract

In this study, we investigate the accuracy of two consecutive ulcer cultures with bone contact compared to bone biopsy for the diagnosis of diabetic toe osteomyelitis. The same nurse and orthopaedic surgeon obtained all samples: sample A-1: bone contact swabbing through the ulcer; sample A-2: a second culture swabbing from the bone surface within 24 h; sample B: surgical bone biopsy in the operating theatre. The kappa statistic measure between samples A-1 and A-2 (bone contact swabs) indicated 82.35% agreement. The sensitivity, specificity, positive and negative predictive values of the two samples A compared to B were 96%, 79%, 92% and 88%, respectively, for the causative pathogen. These results were similar with prior antibiotic treatment, discordant bone surface swabs or with monomicrobial infections. As a conclusion, two consecutive diabetic toe cultures with bone contact accurately predict the pathogen of diabetic toe osteomyelitis in 90% of cases.

Diabetic foot infections: state‐of‐the‐art

“…In particular, most studies with diabetic foot osteomyelitis have found that neither superficial nor deep soft tissue cultures correlate well with those of bone specimens . One study suggested, however, that repeated bone surface swabbing yields similar results compared with bone culture in patients with a wound with underlying clinical osteomyelitis , but this needs to be confirmed in larger trials.…”

Remission in diabetic foot infections: Duration of antibiotic therapy and other possible associated factors

“…We collected samples for culture from pus or deep infected tissue, and did not accept results of cultures, superficial swab specimens or sinus tract. 10 The microbiology laboratory processed all specimens according to Clinical and Laboratory Standards Institute recommendations, 11 before they switched to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria in 2014. 12 We considered remission of DFI as the absence of any clinical, laboratory or imaging evidence of recurrence of the original infection.…”

Stopping antibiotics after surgical amputation in diabetic foot and ankle infections—A daily practice cohort

“…Diabetic foot infections (DFIs) [1][2][3] frequently require amputation, also because of concomitant ischaemia. In these cases, surgeons and physicians regularly debate the duration of post-amputation antibiotics, even in the absence of residual clinical signs of infection.…”