How to make a digital reconstruction of the human ribcage.

Up to now, there have been no publication standardizing the digital reconstruction of the modern human ribcage from commingled costo-vertebral material. Consequently, we designed a validated protocol based on anatomical features observed in the literature and the CT scanned ribcages of 10 adult European individuals. After quantifying the shape of these ribcages using 3D geometric morphometrics, we split each vertebra and rib within their corresponding (semi)landmarks. Subsequently, individual bones + (semi)landmarks were imported to LhpFusionBox, commingled and 3D reconstructed. To validate the accuracy of the protocol, we first reconstructed a randomly chosen ribcage three times and then compared these reconstructions to the rest of the sample. Since these reconstructions were closer to their original counterpart than to the others, the remaining sample was reconstructed once. Next, we tested the intra-observer error during reconstructing using the Procrustes distances among the original ribcages and the reconstructions. We observed that first each ribcage reconstruction was clustered to its original counterpart and second there was a learning curve showing an improvement in the reconstruction process over time. Subsequently, we explored general size and shape differences among the original and reconstructed ribcages through a study of centroid size and a permutation test on the Procrustes distances (10,000 permutations), respectively. Specific shape differences between both groups were further examined through a principal component analysis in shape space. None of these analyses found statistical differences between the original and reconstructed ribcages (p > 0.05). Eventually, we extracted the mean shapes of the original ribcages and the reconstructions in order to visualize potential deviations caused by the anatomical considerations of the researcher. These results demonstrate that the protocol is accurate enough to be used when reconstructing a disarticulated human ribcage.

Eco-geographic and sexual variation of the ribcage in Homo sapiens.

Up to now, Allen and Bergmann's rules have been studied in modern humans by analyzing differences in limb length, height, or body mass. However, there are no publications studying the effects of latitude in the 3D configuration of the ribcage. To assess this issue, we digitally reconstructed the ribcages of a balanced sample of 109 adult individuals of global distribution. Shape and size of the ribcage was quantified using geometric morphometrics. Our results show that the ribcage belonging to tropical individuals is smaller and slenderer compared to others living in higher latitudes, which is in line with Allen and Bergmann's rules and suggests an allometric relationship between size and shape. Although sexual dimorphism was observed in the whole sample, significant differences were only found in tropical populations. Our proposal is that, apart from potential sexual selection, avoiding heat loss might be the limiting factor for sexual dimorphism in cold-adapted populations.

Disentangling the role of virus infectiousness and awareness-based human behavior during the early phase of the COVID-19 pandemic in the European Union.

In this work, we manage to disentangle the role of virus infectiousness and awareness-based human behavior in the COVID-19 pandemic. Using Bayesian inference, we quantify the uncertainty of a state-space model whose propagator is based on an unusual SEIR-type model since it incorporates the effective population fraction as a parameter. Within the Markov Chain Monte Carlo (MCMC) algorithm, Unscented Kalman Filter (UKF) may be used to evaluate the likelihood approximately. UKF is a suitable strategy in many cases, but it is not well-suited to deal with non-negativity restrictions on the state variables. To overcome this difficulty, we modify the UKF, conveniently truncating Gaussian distributions, which allows us to deal with such restrictions. We use official infection notification records to analyze the first 22 weeks of infection spread in each of the 27 countries of the European Union (EU). It is known that such records are the primary source of information to assess the early evolution of the pandemic and, at the same time, usually suffer underreporting and backlogs. Our model explicitly accounts for uncertainty in the dynamic model parameters, the dynamic model adequacy, and the infection observation process. We argue that this modeling paradigm allows us to disentangle the role of the contact rate, the effective population fraction, and the infection observation probability across time and space with an imperfect first principles model. Our findings agree with phylogenetic evidence showing little variability in the contact rate, or virus infectiousness, across EU countries during the early phase of the pandemic, highlighting the advantage of incorporating the effective population fraction into pandemic modeling for heterogeneity in both human behavior and reporting. Finally, to evaluate the consistency of our data assimilation method, we performed a forecast that adequately fits the actual data. Statement of significance: Data-driven and model-based epidemiological studies aimed at learning the number of people infected early during a pandemic should explicitly consider the behavior-induced effective population effect. Indeed, the non-isolated, or effective, fraction of the population during the early phase of the pandemic is time-varying, and first-principles modeling with quantified uncertainty is imperative for an adequate analysis across time and space. We argue that, although good inference results may be obtained using the classical SEIR type model, the model posed in this work has allowed us to disentangle the role of virus infectiousness and awareness-based human behavior during the early phase of the COVID-19 pandemic in the European Union from official infection notification records.

Unravelling hip-spine bone mineral density discordance in people living with HIV.

INTRODUCTION: In people living with HIV (PLWH), bone mineral density (BMD) discordance between the lumbar spine (LS) and femoral neck (FN) could be frequent given the high frequency of secondary osteoporosis, including HIV-related factors for bone disease. MATERIALS AND METHODS: Retrospective cohort of PLWH with a dual X-ray absorptiometry scan. Hip-spine BMD discordance was defined as different T-score or Z-scores categories at LS and FN. RESULTS: Overall, 865 individuals (mean 49.5 years, female 27%) were included. Osteoporosis diagnosis was four-to-seven times lower when both skeletal sites were affected than when considering the lowest T-score at any site (overall, 21% vs 4%). Hip-spine BMD discordance was observed in 381 (44%) individuals, it increased with age (from 43 to 52%, P = 0.032), and it was mainly due to lower LS-BMD. A lower FN-BMD was associated with older age, lower BMI (P < 0.01), and HIV-related factors, such as low CD4 + T-cell counts, duration of HIV infection, and time on antiretroviral therapy (ART). In a multivariate regression analysis, sex male (Odds Ratio, OR 4.901), hyperparathyroidism (OR, 2.364), and time on ART (OR 1.005 per month) were independently associated with discordance. A higher estimated fracture risk by FRAX equation was observed in individuals with BMD discordance due to lower FN-BMD compared to those with lower LS-BMD (+ 36% for major osteoporotic fracture, P = 0.04; + 135% for hip fracture, P < 0.01). CONCLUSION: Hip-spine BMD discordance is highly prevalent in PLWH and it is associated with classical and HIV-related risk factors, modifying the rate of osteoporosis and fracture risk estimation.

Preoperative hydration with 0.9% normal saline to prevent acute kidney injury after major elective open abdominal surgery: A randomised controlled trial.

BACKGROUND: Postoperative acute kidney injury (AKI) is the second leading cause of hospital-acquired AKI. Although many preventive strategies have been tested, none of them has been totally effective. OBJECTIVE: We investigated whether preoperative intravenous hydration with 0.9% normal saline could prevent postoperative AKI. DESIGN: Randomised controlled trial. SETTING: University Ramón y Cajal Hospital, Spain, from June 2006 to February 2011. PATIENTS: Total 328 inpatients scheduled for major elective open abdominal surgery. INTERVENTION: 0.9% normal saline at a dose of 1.5 ml kg h for 12 h before surgery. MAIN OUTCOME MEASURES: The primary outcome was the overall postoperative AKI incidence during the first week after surgery defined by risk, injury, failure, loss, end-stage kidney disease (RIFLE) and AKI network (AKIN) creatinine criteria. Secondary endpoints were the need for ICU admission, renal replacement therapy during the study period and adverse events and hospital mortality during hospital admission. RESULTS: There was no difference in the incidence of AKI between groups: 4.7% in the normal saline group versus 5.0% in the control group and 11.4% in the 0.9% normal saline group versus 7.9% in the control group as assessed by the RIFLE and AKIN creatinine criteria, respectively. Absolute risk reductions (95% confidence interval) were -0.3% (-5.3 to 4.7%) for RIFLE and 3.5% (-10.2 to 3.6%) for AKIN. ICU admission after surgery was required in 44.5% of all participants. Only 2 (0.7%) patients required renal replacement therapy during the first week after surgery. The analysis of adverse events did not show statistically significant differences between the groups except for pain. In our population, 8 (2.4%) patients died during their hospital admission. CONCLUSION: Intravenous hydration with 0.9% normal saline before major open abdominal surgery was not effective in preventing postoperative AKI. No safety concerns were identified during the trial. TRIAL REGISTRATIONS: Clinical trials.gov: NCT00953940 and EUDRA CT: 2005-004755-35.

Surgical neurolysis for the treatment of neuropathic pain in 2 postmenopausal women with mandibular necrosis resulting from oral bisphosphonates.

We analyze the use of surgical neurolysis for the treatment of neuropathic pain of the inferior alveolar nerve. For that, 3 surgical neurolysis were performed on 2 postmenopausal women experiencing neuropathic pain of the inferior alveolar nerve due to mandibular necrosis resulting from treatment with oral bisphosphonates. Both patients showed sensory impairment of the inferior alveolar nerve. We obtained complete control of neuropathic pain after 6 months of the patients' evolution, preserving the function of the lingual nerve in all 3 neurolysis, without causing any impact as regards to the sensitive situation before treatment. Surgical neurolysis of the inferior alveolar nerve may be considered as the choice therapeutic technique to treat neuropathic pain of this nerve when there is a sensory impairment in patients showing mandibular necrosis resulting from bisphosphonates.

Covariation between the shape and mineralized tissues of the rib cross section in Homo sapiens, Pan troglodytes and Sts 14.

OBJECTIVES: Studying rib torsion is crucial for understanding the evolution of the hominid ribcage. Interestingly, there are variables of the rib cross section that could be associated with rib torsion and, consequently, with the morphology of the thorax. The aim of this research is to conduct a comparative study of the shape and mineralized tissues of the rib cross section in different hominids to test for significant differences and, if possible, associate them to different thoracic morphotypes. MATERIALS AND METHODS: The sample consists of the rib cross sections at the midshaft taken from 10 Homo sapiens and 10 Pan troglodytes adult individuals, as well as from A. africanus Sts 14. The shape of these rib cross sections was quantified using geometric morphometrics, while the mineralized tissues were evaluated using the compartmentalization index. Subsequently, covariation between both parameters was tested by a Spearman's ρ test, a permutation test and a linear regression. RESULTS: Generally, P. troglodytes individuals exhibit rib cross sections that are rounder and more mineralized compared to those of H. sapiens. However, the covariation between both parameters was only observed in typical ribs (levels 3-10). Although covariation was not found in the rib cross sections of Sts 14, their parameters are closer to P. troglodytes. DISCUSSION: On the one hand, the differences observed in the rib cross sections between H. sapiens and P. troglodytes might be related to different degrees of rib torsion and, consequently, to different thoracic 3D configurations. These findings can be functionally explained by considering their distinct modes of breathing and locomotion. On the other hand, although the rib cross sections belonging to Sts 14 are more similar to those of P. troglodytes, previous publications determined that their overall morphology is closer to modern humans. This discrepancy could reflect a diversity of post-cranial adaptations in Australopithecus.

How accurate are medical CT and micro-CT techniques compared to classical histology when addressing the growth of the internal rib parameters?

Rib internal anatomy and its cross-sectional morphology inform about important biomechanical or even evolutionary aspects. Classic histological studies require destructive techniques that are reprehensible depending on the case (e.g., fossils). In the last years, non-destructive CT-based methods are contributing to complementing previous knowledge without damaging the bone. Even though these methods have been proved to be useful to understand adult variation, we do not know whether these methods are useful to cover ontogenetic variation. This work compares classical histological methods with medical- and micro-CT to quantify the amount of mineral area at the rib midshaft (% Min. Ar.), a proxy for bone density. We compared cross-sections from an ontogenetic sample of 14 human first ribs ranging from perinates to adults using a) classical histology, b) HD (9-17 microns) and SD micro-CT (90 microns), and c) standard medical-CT (0.66 mm). We found that all the CT-based methods provide a larger % Min. Ar. compared to the histological techniques, but the HD micro-CT resolution is the only capable of producing results comparable to classical histology (p > 0.01), with the SD micro-CT and the medical-CT producing statistically larger results compared to classical histology (p < 0.01). In addition, it is important to state that the resolution of a standard medical-CT is not high enough to differentiate between mineral and non-mineral areas of the cross-sections for perinates and infants. These results could have important implications to avoid (when necessary) destructive techniques that are not appropriate in the case of highly valuable specimens such as fossils.

An analysis of oral biopsies extracted from 1995 to 2009, in an oral medicine and surgery unit in Galicia (Spain).

OBJECTIVE: To conduct an analysis of the frequency of oral lesions in biopsies over a 14-year period in the Oral Medicine, Oral Surgery and Implantology Unit. MATERIAL AND METHODS: We conducted a retrospective study of biopsies removed from 1995-2009, recording data regarding age, sex, location of the lesions, biopsy types, anatomical and pathological diagnosis and definitive diagnosis. RESULTS: Of the 562 patients studied, the average age was 51.8 years, with a standard deviation of 18.5 (range 5-96). The distribution by sex was 318 (56.6%) women and 244 (43.4%) men. The most common diagnostic category was mucosal pathologies in 37.9% of cases, followed by odontogenic cysts in 27.8%. Malignant tumors accounted for 3.9% of cases, oral squamous cell carcinomas were the most frequent malignancy, appearing in 22 cases. Bisphosphonate-related osteonecrosis of the jaws was the most common injury within the bone lesions group. CONCLUSION: Following the performance of 647 biopsies on 562 patients, we can say that the most common injury was radicular cysts (appearing in 108 cases), having found statistical differences in relation to the patients' sex and age.

Lost in Translation: Evaluation of Subcutaneous Interferon-ß Treatment for SARS-CoV-2 Infection in Real Life.

Despite in vitro activity of interferon-ß (IFN-ß) against SARS-CoV-2 infection, its clinical efficacy remains controversial. We evaluated the impact of IFN-ß treatment in a cohort of 3590 patients hospitalized with COVID-19 during March−April 2020. The primary endpoint was a composed variable of admission to intensive care unit (ICU)/death. Overall, 153 patients (4%) received IFN-ß. They were significantly more severely ill, with a worse clinical and analytical situation, explaining a higher ICU admission (30% vs. 17%; p < 0.01), and a shorter time to the composed variable. In a Cox regression analysis, older age, lymphopenia, renal failure, or increased neutrophil-to-lymphocyte ratio were associated with a greater hazard ratio (HR) of admission at ICU/death. Notably, the HR of IFN-ß for the outcome variable was no longer significant after adjustment (HR, 1.03; 95% CI, 0.82−1.30), and different sensitivity analysis (early IFN use, ICU admission) showed no changes in the estimates. A propensity score matching analysis showed no association of IFN-ß therapy and outcome. In conclusion, in this large cohort of hospitalized COVID-19 patients, IFN-ß was used mainly in patients with advanced disease, reflecting an important bias of selection. After adjusting by severity, IFN-ß was not associated with a higher rate of ICU admission or mortality.

Blood loss in orthognathic surgery: a systematic review.

PURPOSE: Intraoperative blood loss during orthognathic surgery is frequently abundant and sometimes requires blood transfusion. The aim of the present study was to conduct a systematic review of the published data regarding intraoperative blood loss during orthognathic surgical interventions, including Le Fort I osteotomy, mandibular ramus osteotomy, and both combined, to determine the range of information available to help surgeons better prepare themselves, their patients, and the auxiliary support needed for this type of surgery and the transfusion requirements. MATERIALS AND METHODS: Selected reports from the PubMed and Cochrane Library databases for studies conducted from 1978 to 2008 were evaluated to determine whether they included information on the volume of bleeding during surgery and the factors that might have influenced the amount of bleeding. Of the 90 reports examined and evaluated, 7 were included in the critical analysis conducted as a part of the present systematic review. RESULTS: Referring to the reports used for statistical analysis of the volume of blood loss, the mean intraoperative bleeding volume was 436.11 mL, the mean of the standard deviations was ±207.89 mL, and mean surgery duration was 196.9 minutes. CONCLUSIONS: Our results have shown that the intraoperative bleeding observed in patients during Le Fort I or mandibular ramus osteotomies or both combined was less than the limits set for blood transfusion. However, bleeding was occasionally heavier, and surgeons should be prepared for heavier bleeding by reserving blood at a blood bank or by preparing an autotransfusion.

Colistimethate sodium and acute kidney injury: Incidence, risk factors, outcome and prognosis of renal function.

BACKGROUND: Colistimethate sodium (CMS) treatment has increased over the last years, being acute kidney injury (AKI) its main drug-related adverse event. Therefore, this study aimed to evaluate the incidence and risk factors associated with AKI, as well as identifying the factors that determine renal function (RF) outcomes at six months after discharge. MATERIALS AND METHODS: This retrospective study included adult septic patients receiving intravenous CMS for at least 48h (January 2007-December 2014). AKI was assessed using KDIGO criteria. The glomerular filtration rate (GFR) was estimated by the 4-variable MDRD equation. Logistic and linear models were performed to evaluate the risk factors for AKI and chronic kidney disease (CKD). RESULTS: Among 126 patients treated with CMS; the incidence of AKI was 48.4%. Sepsis-severe sepsis (OR 8.07, P=0.001), sepsis-septic shock (OR 42.9, P<0.001), and serum creatinine (SCr) at admission (OR 6.20, P=0.009) were independent predictors. Eighty-four patients survived; the main factors for RF evolution at the 6-month follow-up was baseline eGFR (0.58, P<0.001) and at discharge (0.34, P<0.001). Fifty-six percent (34/61) of the patients that developed AKI survived. At six months, 32% had CKD. CONCLUSIONS: The development of AKI in septic patients with CMS treatment was associated with sepsis severity and SCr at admission. Baseline eGFR and eGFR at discharge were and important determinant of the RF at the 6-month follow-up. These predictors may assist in clinical decision making for this patient population.

Peri-implant bone resorption around implants placed in alveolar bone subjected to distraction osteogenesis.

PURPOSE: This study was conducted to evaluate bone resorption around implants placed in alveolar bone previously subjected to distraction osteogenesis (DO). PATIENTS AND METHODS: The study included 9 patients who had undergone alveolar DO with subsequent placement of 37 implants. None of the implants was lost. Vertical peri-implant bone deficit was measured on the distal and mesial surfaces from panoramic radiographs obtained at implant loading and again 1 year later. Resorption over the year of loading was calculated as the increase in vertical bone deficit. RESULTS: Mean peri-implant bone resorption over the first year after loading was 0.60 mm mesially and 0.68 mm distally. In both cases, the resorption (ie, the difference between the mean bone deficit at loading and 1 year later) was statistically significant (P < .05). CONCLUSION: Vertical bone resorption around implants placed in distracted alveolar bone is similar to that seen around implants placed in nondistracted bone.

Botulinum toxin A for treating muscular contractures in cephalic tetanus.

OBJECTIVE: This study reports the use of botulinum toxin for treatment of muscle contractures in a patient with cephalic tetanus. METHOD: Case report. RESULTS: An 80-year-old woman was diagnosed with cephalic tetanus, with contractures of the masseter, sternocleidomastoid, trapezius, and levator scapulae muscles. After one month of conventional treatment good recovery was observed, but with persistence of the contractures of the sternocleidomastoid, trapezius and levator scapulae. These contractures were treated with botulinum toxin A (75IU in the right sternocleidomastoid, 25IU in the right trapezius; one month later 50IU in the left levator scapulae, 50IU in the right levator scapulae, 75IU in the left sternocleidomastoid; two months later 25IU in the left trapezius). Full recovery was observed. CONCLUSIONS: Local infiltration with botulinum toxin A appears to be an effective treatment for persistent muscle contracture in cephalic tetanus.

Changes in Kidney Function and in the Rate of Tubular Dysfunction After Tenofovir Withdrawal or Continuation in HIV-Infected Patients.

INTRODUCTION: Longitudinal data on the changes in kidney function and tubular abnormalities in case of tenofovir disoproxil fumarate (TDF) withdrawal or continuation are scarce. METHODS: Prospective study of 228 patients receiving TDF, with 3 sequential determinations of serum creatinine, estimated glomerular filtration rate (eGFR), phosphatemia, and different urinary parameters (protein, albumin, phosphaturia, uricosuria, and glycosuria). Changes were analyzed in patients who interrupted TDF as compared to those who continued the same regimen. Proximal renal tubular dysfunction (PRTD) was defined as ≥2 tubular abnormalities. RESULTS: After a median follow-up of 59.5 months, 78 patients (34%) had PRTD, mainly proteinuria (40%) and phosphaturia (61%), and time on TDF explains the severity of tubular alterations and eGFR slopes. In 35 switching patients, there was a rapid and significant eGFR improvement (median +4.1 ml/min per 1.73 m; P = 0.02), leading to a 39%-83% reduction in the prevalence of tubular abnormalities and of PRTD in less than 1 year (66%-39%). In comparison, 193 patients continuing the same regimen for 21.2 months had a small but significant and progressive eGFR decrease (-2.9 mL·min·1.73 m; P < 0.01), and a progressive rise in the prevalence of phosphaturia, uricosuria, and glycosuria (+9%-56%). In linear mixed-effect model, subsequent eGFR impairment was associated with proteinuria and time on TDF, and eGFR improvement with TDF discontinuation. CONCLUSIONS: Our data support the role of use and time on TDF in eGFR decline and tubular dysfunction. In contrast, TDF withdrawal is followed by a rapid and significant, although partial, recovery of eGFR and tubular abnormalities.

Prevalence and significance of proximal renal tubular abnormalities in HIV-infected patients receiving tenofovir.

OBJECTIVES: Patients receiving tenofovir, disoproxil, fumarate (TDF) had an increased prevalence of proximal renal tubular dysfunction (PRTD), but contributing factors and its clinical significance remain controversial. DESIGN AND METHODS: Cross-sectional evaluation of different urinary parameters (proteinuria, albuminuria, phosphaturia, uricosuria, glycosuria) in 200 HIV-infected patients receiving TDF, 26 following TDF discontinuation, and 22 never treated with TDF, included in a prospective cohort study. PRTD was defined as two or more tubular abnormalities. RESULTS: After a median of 65 months (interquartile range, 42.7-84.7), at least one tubular alteration was found in 72% of patients, mostly proteinuria (42, 50, and 14% in current, previous and never TDF use; P=0.02) and phosphaturia (46, 42, and 14%; respectively, P < 0.01). PRTD was found in 63 patients (32%) receiving TDF, ranging from 14 to 46% according to concomitant hepatitis C virus coinfection, diabetes mellitus or hypertension arterial, in contrast with six (23%) following TDF discontinuation, and zero cases in no TDF-treated patients. The use of TDF [odds ratio (OR) 13.2; 95% confidence interval (CI) 1.4-22.7; P = 0.01], cumulative time on combination antiretroviral therapy (OR 1.011; 95% CI 1.07-1.019 per month; P = 0.01), and baseline estimated glomerular filtration rate (eGFR, OR 0.97; 95% CI 0.94-0.99 per ml/min per 1.73 m higher; P = 0.04) were associated with PRTD. The number of tubular abnormalities was linearly associated with eGFR decline since TDF initiation (ß-coefficient -0.15, P = 0.02), together with age (-0.18; P = 0.01), baseline eGFR (0.49, P = 0.01), diabetes mellitus (-0.19, P = 0.02), and time on TDF (-0.23; P = 0.01). CONCLUSION: The use of TDF leads to an increased rate of tubular dysfunction, and modulated by age, baseline eGFR, and classical factors, is associated with kidney function decline.

Bone mineral density decline according to renal tubular dysfunction and phosphaturia in tenofovir-exposed HIV-infected patients.

INTRODUCTION: The mechanisms underlying the effect of tenofovir disoproxil fumarate (TDF) on the decline of bone mineral density (BMD) have not been established, especially the effect of renal tubular dysfunction. METHODS: Longitudinal study of 90 patients with two successive dual X-ray absorptiometry scans after evaluation of serum and urinary parameters (proteinuria, albuminuria, phosphaturia, uricosuria, glycosuria, ß-2-microglobulin, and retinol-binding protein). RESULTS: After a median of 38 months on TDF, osteopenia at spine and hip was observed in 49 and 48%, and osteoporosis in 9 and 2%, respectively. There was a lineal correlation between BMD at femoral neck and time on TDF (Spearman's rho = -0.27; P = 0.01). One or more tubular abnormalities were observed in 80% of cases (hyperphosphaturia, 50%). A lower BMD correlated with phosphaturia (r = -0.25; P = 0.03), even with phosphataemia within normal limits. In fact, patients with previous improvement in phosphaturia had better BMD at inclusion (Spearman's rho = -0.33; P < 0.01). A second dual X-ray absorptiometry, after a median of 40.8 months (33.8-45.1; 627.7 patients-year on TDF), showed additional BMD reduction at hip in 50% of cases (36% with bone loss >3%), a decline associated with phosphaturia (ß, -0.31; P = 0.01) or number of tubular abnormalities (ß, -0.41; P = 0.01), but also with use of boosted protease inhibitors (ß, -0.47; P = 0.03) and BMD at inclusion (ß, -0.33; P = 0.03). CONCLUSION: Chronic abnormal phosphaturia explains, at least in part, progressive bone loss during TDF therapy. These data suggest that tubular dysfunction leads to an altered equilibrium between phosphataemia, phosphaturia, and bone as mechanism of progressive BMD decline.

Impact of a new definition of acute kidney injury based on creatinine kinetics in cardiac surgery patients: a comparison with the RIFLE classification.

OBJECTIVES: Acute kidney injury (AKI) after cardiac surgery is associated with adverse patient outcome. A new definition and staging system for AKI based on creatinine kinetics (CKs) has been proposed recently. Their proponents hypothesize that early absolute increases in serum creatinine (sCr) after kidney injury are superior to percentage increases, especially in patients with chronic kidney disease (CKD). The aims of our study were to measure agreement between CK definition and the current consensus definition [risk, injury, failure, loss and end-stage renal disease (RIFLE) system], and to compare time to diagnosis and prognostic value between both systems. METHODS: Retrospective cohort study. Agreement on AKI diagnosis by both classifications, time to diagnosis and prognostic value of both systems were compared in cardiac surgeries performed during a 6-year period (2002-2007) in a single centre. RESULTS: We found substantial agreement between both classifications (0.67). More patients were diagnosed with AKI by the CK definition than by RIFLE criteria both globally (28.2 vs 13.9%) and in every category (16.5 vs 8.4% for CK-1 vs RIFLE-R; 8.4 vs 3.6% for CK-2 vs RIFLE-I and 3.2 vs 2.0% for CK-3 vs RIFLE-F). Time to diagnosis was shorter for the CK definition (1.8 vs 2.5 days). Prognostic value in terms of information about in-hospital death and need for renal replacement was comparable between classifications. CONCLUSIONS: In cardiac surgery, the CK definition and classification system showed substantial agreement with the current standard, was more sensitive than RIFLE and detected AKI earlier without loss of prognostic information.