Surgical Treatment of Diabetic Foot Ulcers Complicated by Osteomyelitis with Gentamicin-Loaded Calcium Sulphate-Hydroxyapatite Biocomposite

Diabetic foot ulcers, complicated by osteomyelitis, can be treated by surgical resection, dead space filling with gentamicin-loaded calcium sulphate-hydroxyapatite (CaS-HA) biocomposite, and closure of soft tissues and skin. To assess the feasibility of this treatment regimen, we conducted a multicenter retrospective cohort study of patients after failed conventional treatments. From 13 hospitals we included 64 patients with forefoot (n = 41 (64%)), midfoot (n = 14 (22%)), or hindfoot (n = 9 (14%)) ulcers complicated by osteomyelitis. Median follow-up was 43 (interquartile range, 20-61) weeks. We observed wound healing in 54 patients (84%) and treatment success (wound healing without ulcer recurrence) in 42 patients (66%). Treatment failures (no wound healing or ulcer recurrence) led to minor amputations in four patients (6%) and major amputations in seven patients (11%). Factors associated with treatment failures in univariable Cox regression analysis were gentamicin-resistant osteomyelitis (hazard ratio (HR), 3.847; 95%-confidence interval (CI), 1.065-13.899), hindfoot ulcers (HR, 3.624; 95%-CI, 1.187-11.060) and surgical procedures with gentamicin-loaded CaS-HA biocomposite that involved minor amputations (HR, 3.965; 95%-CI, 1.608-9.777). In this study of patients with diabetic foot ulcers, complicated by osteomyelitis, surgical treatment with gentamicin-loaded CaS-HA biocomposite was feasible and successful in 66% of patients. A prospective trial of this treatment regimen, based on a uniform treatment protocol, is required

1-Year Results of a Multicenter Randomized Controlled Trial Comparing Heparin-Bonded Endoluminal to Femoropopliteal Bypass

OBJECTIVES: This study sought to compare heparin-bonded endografts with femoropopliteal bypass, including quality of life, using general health and disease-specific questionnaires as well as patency rates. BACKGROUND: Endovascular treatment continues to advance and is gaining acceptance as primary treatment for long occlusive or stenotic lesions in the superficial femoral artery. Heparin-bonded expanded polytetrafluoroethylene endografts have been related to outcomes comparable to bypass surgery, but this has not been tested in a randomized fashion. METHODS: A multicenter randomized-controlled trial was performed comparing femoropopliteal bypass with heparin-bonded expanded polytetrafluoroethylene endografts. Data were analyzed on an intention-to-treat and per-protocol manner. RESULTS: A total of 129 patients were randomized and 125 patients were treated, 63 in the endoluminal and 62 in the surgical group (42 venous, 20 prosthetic). Enrollment was terminated before reaching the predefined target number for patency. Baseline characteristics and anatomical data were similar. Patients were treated for critical limb ischemia in 38.1% and 32.2% in the endoluminal and surgical arms, respectively. Mean lesion length was 23 cm in both groups and lesions were largely TransAtlantic Inter-Society Consensus II D. Hospitalization time and 30-day morbidity were significantly lower in the endoluminal group, without differences in serious adverse events (n = 5 each; surgical: 4 venous and 1 polytetrafluoroethylene bypass). There were no significant differences in Rutherford category between groups at any time point. At 30 days the endoluminal group showed a greater improvement in quality-of-life scores. At 1 year, these differences had largely disappeared and no differences in primary (endoluminal: 64.8%; surgical: 63.6%), assisted primary (endoluminal: 78.1%; surgical: 79.8%), secondary patency (endoluminal: 85.9%; surgical: 83.3%), and target vessel revascularization (endoluminal: 72.1%; surgical: 71.0%) were observed. Limb salvage rate was 100% in both groups. CONCLUSIONS: Heparin-bonded endoluminal bypass for long segment lesions shows promising results (less morbidity, faster recovery, and improvement in quality of life with indistinguishable patency rates at 1 year) compared with surgical bypass. Long-term results have to be awaited

SARS-CoV-2 infects the human kidney and drives fibrosis in kidney organoids

Kidney failure is frequently observed during and after COVID-19, but it remains elusive whether this is a direct effect of the virus. Here, we report that SARS-CoV-2 directly infects kidney cells and is associated with increased tubule-interstitial kidney fibrosis in patient autopsy samples. To study direct effects of the virus on the kidney independent of systemic effects of COVID-19, we infected human-induced pluripotent stem-cell-derived kidney organoids with SARS-CoV-2. Single-cell RNA sequencing indicated injury and dedifferentiation of infected cells with activation of profibrotic signaling pathways. Importantly, SARS-CoV-2 infection also led to increased collagen 1 protein expression in organoids. A SARS-CoV-2 protease inhibitor was able to ameliorate the infection of kidney cells by SARS-CoV-2. Our results suggest that SARS-CoV-2 can directly infect kidney cells and induce cell injury with subsequent fibrosis. These data could explain both acute kidney injury in COVID-19 patients and the development of chronic kidney disease in long COVID

Artificial intelligence : is there a potential role in nephropathology?

Funding Agencies: ERACoSysMeds SysMIFTA project, as part of the European Union [9003035004]</p

Surgical treatment of diabetic foot ulcers complicated by osteomyelitis with gentamicin‐loaded calcium sulphate‐hydroxyapatite biocomposite

Diabetic foot ulcers, complicated by osteomyelitis, can be treated by surgical resection, dead space filling with gentamicin‐loaded calcium sulphate‐hydroxyapatite (CaS‐HA) biocomposite, and closure of soft tissues and skin. To assess the feasibility of this treatment regimen, we conducted a multicenter retrospective cohort study of patients after failed conventional treatments. From 13 hospitals we included 64 patients with forefoot (n = 41 (64%)), midfoot (n = 14 (22%)), or hindfoot (n = 9 (14%)) ulcers complicated by osteomyelitis. Median follow‐up was 43 (interquartile range, 20–61) weeks. We observed wound healing in 54 patients (84%) and treatment success (wound healing without ulcer recurrence) in 42 patients (66%). Treatment failures (no wound healing or ulcer recurrence) led to minor amputations in four patients (6%) and major amputations in seven patients (11%). Factors associated with treatment failures in univariable Cox regression analysis were gentamicin‐resistant osteomyelitis (hazard ratio (HR), 3.847; 95%‐confidence interval (CI), 1.065–13.899), hindfoot ulcers (HR, 3.624; 95%‐CI, 1.187–11.060) and surgical procedures with gentamicin‐loaded CaS‐HA biocomposite that involved minor amputations (HR, 3.965; 95%‐CI, 1.608– 9.777). In this study of patients with diabetic foot ulcers, complicated by osteomyelitis, surgical treatment with gentamicin‐loaded CaS‐HA biocomposite was feasible and successful in 66% of patients. A prospective trial of this treatment regimen, based on a uniform treatment protocol, is required

Quantitative assessment of inflammatory infiltrates in kidney transplant biopsies using multiplex tyramide signal amplification and deep learning

Delayed graft function (DGF) is a strong risk factor for development of interstitial fibrosis and tubular atrophy (IFTA) in kidney transplants. Quantitative assessment of inflammatory infiltrates in kidney biopsies of DGF patients can reveal predictive markers for IFTA development. In this study, we combined multiplex tyramide signal amplification (mTSA) and convolutional neural networks (CNNs) to assess the inflammatory microenvironment in kidney biopsies of DGF patients (n = 22) taken at 6 weeks post-transplantation. Patients were stratified for IFTA development (&amp;lt;10% versus &amp;gt;= 10%) from 6 weeks to 6 months post-transplantation, based on histopathological assessment by three kidney pathologists. One mTSA panel was developed for visualization of capillaries, T- and B-lymphocytes and macrophages and a second mTSA panel for T-helper cell and macrophage subsets. The slides were multi spectrally imaged and custom-made python scripts enabled conversion to artificial brightfield whole-slide images (WSI). We used an existing CNN for the detection of lymphocytes with cytoplasmatic staining patterns in immunohistochemistry and developed two new CNNs for the detection of macrophages and nuclear-stained lymphocytes. F1-scores were 0.77 (nuclear-stained lymphocytes), 0.81 (cytoplasmatic-stained lymphocytes), and 0.82 (macrophages) on a test set of artificial brightfield WSI. The CNNs were used to detect inflammatory cells, after which we assessed the peritubular capillary extent, cell density, cell ratios, and cell distance in the two patient groups. In this cohort, distance of macrophages to other immune cells and peritubular capillary extent did not vary significantly at 6 weeks post-transplantation between patient groups. CD163(+) cell density was higher in patients with &amp;gt;= 10% IFTA development 6 months post-transplantation (p &amp;lt; 0.05). CD3(+)CD8(-)/CD3(+)CD8(+) ratios were higher in patients with &amp;lt;10% IFTA development (p &amp;lt; 0.05). We observed a high correlation between CD163(+) and CD4(+)GATA3(+) cell density (R = 0.74, p &amp;lt; 0.001). Our study demonstrates that CNNs can be used to leverage reliable, quantitative results from mTSA-stained, multi spectrally imaged slides of kidney transplant biopsies. This study describes a methodology to assess the microenvironment in sparse tissue samples. Deep learning, multiplex immunohistochemistry, and mathematical image processing techniques were incorporated to quantify lymphocytes, macrophages, and capillaries in kidney transplant biopsies of delayed graft function patients. The quantitative results were used to assess correlations with development of interstitial fibrosis and tubular atrophy.Funding Agencies|ERACoSysMed initiative (project SysMIFTA) as part of the European Unions Horizon 2020 Framework Programme by ZonMw [9003035004]; German Ministry of Research and Education (BMBF)Federal Ministry of Education &amp; Research (BMBF) [FKZ031L-0085A, FKZ01ZX1710A, FKZ01ZX1608A]; Dutch Kidney Foundation (project DEEPGRAFT) [17OKG23]</p

Deep Learning-Based Histopathologic Assessment of Kidney Tissue

BACKGROUND: The development of deep neural networks is facilitating more advanced digital analysis of histopathologic images. We trained a convolutional neural network for multiclass segmentation of digitized kidney tissue sections stained with periodic acid-Schiff (PAS). METHODS: We trained the network using multiclass annotations from 40 whole-slide images of stained kidney transplant biopsies and applied it to four independent data sets. We assessed multiclass segmentation performance by calculating Dice coefficients for ten tissue classes on ten transplant biopsies from the Radboud University Medical Center in Nijmegen, The Netherlands, and on ten transplant biopsies from an external center for validation. We also fully segmented 15 nephrectomy samples and calculated the network's glomerular detection rates and compared network-based measures with visually scored histologic components (Banff classification) in 82 kidney transplant biopsies. RESULTS: The weighted mean Dice coefficients of all classes were 0.80 and 0.84 in ten kidney transplant biopsies from the Radboud center and the external center, respectively. The best segmented class was "glomeruli" in both data sets (Dice coefficients, 0.95 and 0.94, respectively), followed by "tubuli combined" and "interstitium." The network detected 92.7% of all glomeruli in nephrectomy samples, with 10.4% false positives. In whole transplant biopsies, the mean intraclass correlation coefficient for glomerular counting performed by pathologists versus the network was 0.94. We found significant correlations between visually scored histologic components and network-based measures. CONCLUSIONS: This study presents the first convolutional neural network for multiclass segmentation of PAS-stained nephrectomy samples and transplant biopsies. Our network may have utility for quantitative studies involving kidney histopathology across centers and provide opportunities for deep learning applications in routine diagnostics

Hyperbaric Oxygen Therapy in the Treatment of Ischemic Lower- Extremity Ulcers in Patients With Diabetes: Results of the DAMO(2)CLES Multicenter Randomized Clinical Trial

OBJECTIVEConflicting evidence exists on the effects of hyperbaric oxygen therapy (HBOT) in the treatment of chronic ischemic leg ulcers. The aim of this trial was to investigate whether additional HBOT would benefit patients with diabetes and ischemic leg ulcers.RESEARCH DESIGN AND METHODSPatients with diabetes with an ischemic wound (n = 120) were randomized to standard care (SC) without or with HBOT (SC+HBOT). Primary outcomes were limb salvage and wound healing after 12 months, as well as time to wound healing. Other end points were amputation-free survival (AFS) and mortality.RESULTSBoth groups contained 60 patients. Limb salvage was achieved in 47 patients in the SC group vs. 53 patients in the SC+HBOT group (risk difference [RD] 10% [95% CI -4 to 23]). After 12 months, 28 index wounds were healed in the SC group vs. 30 in the SC+HBOT group (RD 3% [95% CI -14 to 21]). AFS was achieved in 41 patients in the SC group and 49 patients in the SC+HBOT group (RD 13% [95% CI -2 to 28]). In the SC+HBOT group, 21 patients (35%) were unable to complete the HBOT protocol as planned. Those who did had significantly fewer major amputations and higher AFS (RD for AFS 26% [95% CI 10-38]).CONCLUSIONSAdditional HBOT did not significantly improve complete wound healing or limb salvage in patients with diabetes and lower-limb ischemi