Determining factors of pulse oximetry accuracy: a literature review.

OBJECTIVE: Identify and reach consensus on the variables that affect the measurement of oxygen saturation using pulse oximetry. METHODS: We applied inclusion and exclusion criteria to select relevant studies in databases such as Ebsco and PubMed. The search strategies, carried out until December 2023, focused on publications that addressed the technology of pulse oximeters and variables that influence their accuracy. We assessed the risk of bias of the included studies and used standardized methods for synthesis of results. RESULTS: 23 studies were included. The synthesis of the results highlighted that equipment with tetrapolar technology showed greater precision in oxygen saturation measurements. Increased skin pigmentation, hemoglobinopathies and high skin temperatures can lead to an overestimation of SpO2, while factors such as low perfusion, cold skin temperature, nail polish or tattoos, hypoxemia, anemia and high altitude training, they may underestimate it. On the other hand, motion artifacts, light pollution, frequency >150 beats per minute, electromagnetic interference and location of the sensor can cause distortion of the photoplethymography signal. CONCLUSIONS: The synthesis of the results highlighted that skin pigmentation and light interference can lead to an overestimation of SpO2, while other factors such as low perfusion and altitude tend to underestimate it. The studies presented variability and heterogeneity in their designs, evidencing limitations in the consistency and precision of the evidence. Despite these limitations, the results underscore the importance of considering multiple variables when interpreting pulse oximetry measurements to ensure their reliability. The findings have significant implications for clinical practice and future research.

Synchronous bilateral breast cancer treated with a 3-week hypofractionated radiotherapy schedule: clinical and dosimetric outcomes.

BACKGROUND AND PURPOSE: Synchronous bilateral breast cancer (SBBC) accounts for 1-3.5% of breast cancer patients. The aim of this study was to evaluate dosimetric issues, clinical outcomes, and acute toxicities for SBBC patients receiving synchronous bilateral hypofractionated radiotherapy (SBHRT) and to compare them with patients treated with synchronous bilateral normofractionated RT schedule (SBNRT). MATERIALS AND METHODS: From April 2016 to March 2020, 39 SBBC patients were referred to our institution. Patients were divided according to their prescription dose: Group A: 50 Gy/25fx (fractions), B: 60-64 Gy/25fx, C: 40.05 Gy/15fx; D: 48 Gy/15fx. Toxicity was evaluated using Common Terminology Criteria for Adverse Events (CTCAE)v.5.0. RESULTS: 34 patients were finally evaluated. Median follow-up was 24 months for NF schedule and 9 months for HF schedule. In the HF schedule, no acute side-effects > G2 were observed and no dermatitis was reported in 6th month´s assessments. 95% of patients have no evidence of disease and only 1 patient presented local relapse in the first mammography after RT. No distant failures or deaths were observed. Regarding dosimetric issues, the inter-patient average Dmean for the heart was: Group A: 5.0 Gy (4.6-5.5), Group B: 4.4 Gy (4.1-5.4), Group C: 4.8 Gy (4.5-5.1) and Group D: 5.3 Gy (4.4-5.6). For the lungs, the inter-patient average Dmean was: Group A: 10.8 Gy (9.8-12.2), Group B: 11.5 Gy (11.3-12), Group C: 9.8 Gy (9.3-10.5) and Group D: 10.5 Gy (10-11.3). CONCLUSIONS: This is the first study reporting the safety, feasibility, and tolerability of 40.05 Gy/15fx over 3 weeks for the treatment of SBBC patients. Further study with larger accrual is mandatory.

The impact of pipeline changes and temperature increase in a hospital historically colonised with Legionella.

Healthcare-related Legionnaires' disease has a devastating impact on high risk patients, with a case fatality rate of 30-50%. Legionella prevention and control in hospitals is therefore crucial. To control Legionella water colonisation in a hospital setting we evaluated the effect of pipeline improvements and temperature increase, analysing 237 samples over a 2-year period (first year: 129, second year: 108). In the first year, 25.58% of samples were positive for Legionella and 16.67% for amoeba. Assessing the distance of the points analysed from the hot water tank, the most distal points presented higher proportion of Legionella colonisation and lower temperatures (nearest points: 6.4% colonised, and temperature 61.4 °C; most distal points: 50% and temperature 59.1 °C). After the first year, the hot water system was repaired and the temperature stabilised. This led to a dramatic reduction in Legionella colonisation, which was negative in all the samples analysed; however, amoeba colonisation remained stable. This study shows the importance of keeping the temperature stable throughout the circuit, at around 60 °C. Special attention should be paid to the most distal points of the circuit; a fall in temperature at these weak points would favour the colonisation and spread of Legionella, because amoeba (the main Legionella reservoir) are not affected by temperature.

Functional outcomes after prostatic cryosurgery. / Resultados funcionales después de crioterapia prostática.

OBJECTIVE: To assess the functional effects of prostatic cryosurgery on micturition. MATERIAL AND METHODS: Prospective study of men who underwent cryosurgery (CS) for prostate cancer between 2013 - 2015. Low urinary tract symptoms (LUTS) and quality of life (QoL) were assessed 1 month before surgery using IPSS questionnaire, a three-day voiding diary (3DVD) and uroflowmetry with ultrasound-measured postvoid residual volume. Need of medical treatment for LUTS was also recorded. The same assessment was performed at 3, 6 and 12 months after CS. Outcomes after surgery were compared to those prior to surgery. RESULTS: Forty-five patients underwent a CS during the study period, of whom 25 patients could be recruited in the study. Mean age was 73.5 years (range 66-84). Nineteen CS (76%) were performed as a primary procedure, while 6 CS (24%) as a salvage procedure. No statistical differences were found comparing results of IPSS, QoL, D3vd or uroflowmetry and PVR at 3, 6 or 12 months after CS compared to before surgery. Before CS, 8 (32%) patients were on medical treatment for LUTS, while at 6 and 12 months after surgery, 3 (13.6%) and 2 (9.5%) patients required some medication, respectively. CONCLUSION: According to the punctuation of IPSS, QoL questionnaire, and a 3-day voiding diary, LUTS does not worsen after CS. Prostatic cryosurgery does not seem to impact uroflowmetry results.

Desensitization Protocol in Recipients of Deceased Kidney Donor With Donor-Specific Antibody-Low Titers.

BACKGROUND: Kidney transplantation is the better option for end-stage renal disease (ESRD), but for patients with human leukocyte antigen (HLA) sensitization, the wait times are significantly longer than for patients without antibodies. Many desensitization protocols have been described involving strong immunosuppression, the use of apheresis, and B-cell-modulating therapies. We have designed a desensitization protocol from day 0 for deceased donor kidney transplantation. Our aim was to present our initial experience with five kidney transplant patients. METHODS: All patients had a negative complement-dependent cytotoxicity cross-match. The desensitization protocol included five to seven doses of thymoglobulin (1.25 mg/kg) and three sessions of plasmapheresis (PP) within the first week after transplantation, with intravenous immunoglobulin (500 mg/kg) after each PP session and one dose of rituximab on day 8. The presence of donor-specific antibodies (DSA) was analyzed by use of Luminex technology; levels between 1000 and 3000 mean fluorescence intensity were considered for desensitization. RESULTS: The median age was 44 years and median renal replacement therapy time was 9 years. All recipients presented 1 to 3 DSA specificities. There were no severe side effects related to PP, infusion of intravenous immunoglobulin, or rituximab. The median follow-up period was 19.3 months. Median serum creatinine level at last follow-up was 1.7 mg/dL. A kidney biopsy was performed in all patients. Graft and patient survival was 100%. CONCLUSIONS: Until now, few data are available concerning whether HLA-incompatible kidney transplantation after desensitization would benefit patients with ERSD. The desensitization strategy using the combination of PP, low doses of intravenous immunoglobulin, and rituximab at our center resulted in a satisfactory clinical outcome.

A higher Charlson comorbidity index is related to more aggressive characteristics in de novo vesical tumours.

OBJECTIVE: To analyze the relationship between the age--adjusted Charlson Comorbidity Index (aCCI) and pathological outcomes of transurethral resection of de novo bladder tumours (BT). MATERIAL AND METHODS: Data from 208 patients who underwent a transurethral resection (TUR) of a de novo BT between 2007 and 2008 were collected. We recorded the following variables: age, sex, tobacco consumption, comorbidities assessed according to the ICCa (score and mortality rate), disease stage, tumour grade and risk of recurrence and progression. The relationship between the preoperative variables and the final pathological characteristics was analyzed. The multivariate study was conducted with the significant variables (P<.05) from the univariate analysis. RESULTS: The mean age of the patients was 69.5 ± 12 years, and 77% were men. The mean ICCa was 6.4 ± 2.5. The final pathology results showed a Tx, T0, Ta, T1 and T ≥ 2 in 5.3, 6.7, 31.7, 26.9, and 28.8% of the cases, respectively. 33.3% of the tumours were low-grade and 66.7% were high-grade. 14.3% of the tumours were associated with carcinoma in situ. Among those non musculo-invasive bladder tumour (non-MIBT), 34.7% had a low risk of recurrence and progression, 18.1% had an intermediate risk and 47.2% had a high risk. The patients with a ICCa ≥ 5 had an increased number of MIBT (RR: 2.29; 1.1-4.8; P=.032), high-grade tumours (RR: 3.1; CI: 1.6-6; P=.001) and tumours with a high risk of recurrence and progression (RR: 2.9; CI: 1.4-5.9; P<.001). CONCLUSION: The ICCa is related to the pathological characteristics of de novo BT. Patients with greater comorbidity can present more aggressive tumours. The ICCa could therefore be useful in clinical practice for identifying patients with worse prognosis.

Predictors, pathological characteristics and outcomes of bladder recurrences following nephroureterectomy.

OBJECTIVES: To analyze the predictors for bladder recurrence (BR) after nephroureterectomy (NU) for upper urinary tract tumors (UUTT), as well as its pathological characteristics, outcomes and impact on survival. MATERIAL AND METHODS: Retrospective study of 117 patients who underwent laparoscopic nephroureterectomy by UUTT between 2007-2012 at our center. The potential predictors for BR were analyzed using Cox regression; Kaplan-Meier curves were employed to study survival. RESULTS: The sample was composed of 85 men (73%) and 32 women (27%), with a mean age of 70 years. After a mean follow-up of 26 months, 23 patients presented BR (19.6%). In the multivariate analysis, sex (p=.003; HR [female], 3.8) and the location of the UUTT in the distal ureter (p=.002; HR, 4.8) were independent predictors for BR. The median time to BR was 8 months. Fifteen patients presented a nonmuscle-invasive BR (65.2%), and 8 presented a muscle-invasive BR (34.8%). All BRs, except for 2, appeared during the first 2 years. Five cases with nonmuscle-invasive BR presented a new BR. Six patients with muscle-invasive BR died before it could be determined whether cause of death was the BR or an UUTT relapse. The onset of BR showed no repercussion on the survival of patients with UUTT. CONCLUSIONS: Sex (female) and the location of the UUTT (distal ureter) are predictors for BR after NU. Patients with these characteristics might benefit from adjuvant intravesical treatment and closer monitoring. The onset for RV has no impact on the survival of patients with UUTT.

Safety and efficacy of induction treatment with low thymoglobulin doses in kidney transplantation from expanded-criteria donors.

BACKGROUND: Induction treatment has been recommended as part of the initial immunosuppressive regimen in kidney transplantation, and antithymocyte globulin is one of the drugs used for it, but at usual dosage it has been related to an increase of infectious and neoplastic complications. Our aim was to analyze the safety and efficacy of induction treatment with low doses of antithymocyte globulin, compared to basiliximab. METHODS: In this retrospective cohort study of 321 kidney transplant patients with a minimum follow-up of 2 years, 162 were treated with low doses of antithymocyte globulin (1.25 mg/kg, every other day) and 159 with basiliximab. Mean follow-up was 76.6 ± 37.51 months (range, 24-187 mo) and was similar for the 2 groups. RESULTS: Mean number of antithymocyte globulin doses was 1.89 ± 0.32 mg/kg (range, 1-3). The globulin group received a higher proportion of kidneys from donors >70 years old (25.3% vs 13.8%; P = .010) and donors with higher creatinine levels (1.01 ± 0.62 vs 0.86 ± 0.28 mg/dL; P = .006). The basiliximab group presented a higher incidence of acute rejection (22.1% vs 9.1%; P = .010). Cytomegalovirus disease was more frequent in the globulin group (18.6% vs 8.1%; P = .011) without an increase of infectious hospitalizations. Graft (P = .214) and patient (P = .533) survivals were similar. CONCLUSIONS: Induction with low doses of antithymocyte globulin resulted in a lower incidence of acute rejection with graft and patient survivals similar to that obtained with basiliximab induction, in spite of a worse donor profile. CMV disease was more frequent with antithymocyte globulin, without an increase of infectious hospitalizations or cancer development, in long-term follow-up.

[Hemodynamic monitoring in the critically patient. Recomendations of the Cardiological Intensive Care and CPR Working Group of the Spanish Society of Intensive Care and Coronary Units]. / Monitorización hemodinámica en el paciente crítico. Recomendaciones del Grupo de Trabajo de Cuidados Intensivos Cardiológicos y RCP de la Sociedad Española de Medicina Intensiva, Crítica y Unidades Coronarias.

Hemodynamic monitoring offers valuable information on cardiovascular performance in the critically ill, and has become a fundamental tool in the diagnostic approach and in the therapy guidance of those patients presenting with tissue hypoperfusion. From introduction of the pulmonary artery catheter to the latest less invasive technologies, hemodynamic monitoring has been surrounded by many questions regarding its usefulness and its ultimate impact on patient prognosis. The Cardiological Intensive Care and CPR Working Group (GTCIC-RCP) of the Spanish Society of Intensive Care and Coronary Units (SEMICYUC) has recently impulsed the development of an updating series in hemodynamic monitoring. Now, a final series of recommendations are presented in order to analyze essential issues in hemodynamics, with the purpose of becoming a useful tool for residents and critical care practitioners involved in the daily management of critically ill patients.

Pretransplant donor-specific HLA antibodies detected by single antigen bead flow cytometry: risk factors and outcomes after kidney transplantation.

BACKGROUND: The clinical significance of pretransplant donor-specific antibodies (pre-Tx DSAs) detected by single antigen bead flow cytometry (SAB-FC) remains unclear. Our aim was to investigate the impact that pre-Tx DSAs detected by SAB-FC have on the early and late clinical outcomes. PATIENTS AND METHODS: We retrospectively tested stored frozen pre-Tx sera from 222 deceased-donor kidney transplants performed between November 1997 and November 2006. All patients had a negative complement-dependent cytotoxicity (CDC) cross-match with the donor. Median follow up was 5.1 years. RESULTS: Twenty-two (10%) patients had pre-Tx HLA antibodies detected by CDC. Pre-Tx HLA antibodies were detected using SAB-FC in the sera of 46 (20.7%) patients; 36 (16.2%) of them presented pre-Tx DSAs, 18 had class I antibodies, 9 class II, and 9 patients presented both classes. Mean pre-Tx DSA class I/II was 2360/1972 (MFI) mean fluorescence index in non CDC-sensitized patients. Pre-Tx DSAs were associated with female sex, retransplants, and pretransplant transfusions. Patients with Pre-Tx DSAs more than 1000 MFI and negative CDC screening presented a higher percentage of delayed graft function (61.1% versus 38.9%), more episodes of acute vascular rejection (33.3% versus 13.7%), and chronic rejection as the cause of allograft failure (22.2% versus 9.7%) compared with non-pre-Tx DSAs patients. Five-year allograft survival was significantly worse in patients with pre-Tx DSA (68.5% versus 82%, P = .006) and in patients with pre-Tx DSA class II more than 1000 MFI (43% versus 82%, P = .009). We didn't find differences in patient survival. DISCUSSION: Pre-Tx DSAs detected by SAB-FC were more frequent in female recipients, and they were associated with acute vascular and chronic rejection and a poorer graft outcome.

Donor-specific HLA antibodies: risk factors and outcomes after kidney transplantation.

BACKGROUND: Anti-human leukocyte antigen antibodies (HLA Abs) have been associated with reduced kidney allograft survival. Our aim was to analyze the prevalence and impact on allograft function of donor-specific HLA antibodies (DSA) among a cohort of kidney transplant recipients. PATIENTS AND METHODS: The 321 recipients had received deceased-donor kidneys followed for a median of 70 ± 43 months. We performed a cross-sectional analysis of the presence of HLA Abs with the use of Luminex technology. RESULTS: Fifty patients (15.6%) displayed HLA Abs after transplantation including 21 (6.7%) as de novo HLA Abs. Eight patients (2.5%) developed DSA, and 42 (13%) showed no DSA. We compared 3 groups of patients: with DSA, without DSA, and without HLA sensitization. The DSA patients were younger (P = .03) with a higher percentage of men (P = .00), and having received less frequent induction treatment with basiliximab or thymoglobulin (P = .02). Patients without DSA revealed a higher percentage of pretransplantation HLA sensitization (P = .00), more pretransplantation transfusions (P = .08), and more frequent retransplantations (P = .00). The incidence of acute rejections was higher for DSA patients (P = .02) than for the other 2 groups, behaving as an independent risk factor (relative risk, 4.7; 95% confidence interval, 1.1-18.8; P = .03). Graft survival at 5 years was lower among patients with compared to those without HLA Abs (P = .00). CONCLUSIONS: HLA donor-specific sensitization, an uncommon situation in our study, was associated with younger male recipients and less induction treatment. An acute rejection episode was an independent risk factor for the development of DSA; therefore, we think that monitoring of HLA Abs should be included in evaluation of the early postransplantation period.

Delayed graft function after renal transplantation: an unresolved problem.

Unlike other areas in renal transplantation, delayed graft function (DGF) remains an apparently unavoidable complication owing to the characteristics of current donors. The aim of this study was to analyze risk factors for DGF in relation to graft and patient survivals. We retrospectively analyzed 507 renal transplant recipients with a median follow-up of 74.83 ± 45.06 months. DGF, which occurred among 189 patients (36.8%) was defined as requirement for dialysis within the first week after transplantation. Donor (P = .000) and recipient (P = .000) age were greater in the DGF group without differences in recipient or donor gender, HLA sensitization, or dialysis time before transplantation. Donor factors as the cause of death associated with DGF were secondary cerebrovascular stroke (P = .002) and hypertensive history (P = .000). Recipient characteristics associated therewith were higher body mass index (P = .000), smoking habit (P = .003), ischemic cardiopathy (P = .01), and dyslipidemia (P = .05). Moreover, the DGF group showed longer cold ischemia (P = .01) and vascular anastomosis (P = .02) times. On multivariate analysis, recipient age (P = .00) and smoking habit (P = .01) together with a donor history of hypertension (P = .02) were independent risk factors for DGF. No differences were observed in acute rejection incidence (P = .07) with worse renal function during follow-up (P < .05). Graft (81% vs 88%; P = .00) and patient (89% vs 95%; P = .00) survivals at 5 years were lower among the DGF group. In conclusion, DGF which was associated with factors related to the donor, the recipient, and the surgical times, produced worse graft and patient survivals. Shortening the cold ischemia time seems to be a modifiable variable to reduce DGF.

[Estimating cardiac output. Utility in the clinical practice. Available invasive and non-invasive monitoring]. / Estimación del gasto cardíaco. Utilidad en la práctica clínica. Monitorización disponible invasiva y no invasiva.

This aim of this review is to provide a detailed review of the physiologic conditions and variables of the cardiac output, as well as review the different techniques available for its measurement. We also want to establish the clinical situations in which the measurement of cardiac output can add valuable information for the management of critically ill patients. The Fick technique, used in the beginning to calculate cardiac output, has been replaced today by thermodilution techniques (transcardiac or transpulmonary), lithium dilution, bioreactance, Doppler technique or echocardiography. Pulse wave analysis allows a continuous minimally invasive cardiac output measurement. Other methods, such bioreactance, Doppler technique or echocardiography currently provide a valid, fast and non-invasive measurement of cardiac output.

Vitamin D deficiency in a renal transplant population: safe repletion with moderate doses of calcidiol.

BACKGROUND: Deficits of vitamin D are a common finding in the general population, especially among patients with chronic kidney disease. However, there are not much data about its prevalence after renal transplantation. Our aim was to analyze the calcidiol status among a cohort of kidney transplant recipients, in a region of Spain with a high number of annual sunshine hours, as well as the effects of supplementation with oral calcidiol. PATIENTS AND METHODS: We included 110 kidney transplant recipients in a retrospective observational study. Measurements of 25-hydroxyvitamin D (25OHD), calcium, phosphate, intact parathyroid hormone (iPTH), serum creatinine and albumin, 24-hour microalbuminuria, and proteinuria were performed at the same time. Patients were classified based on their serum 25OHD levels: normal (>30 ng/mL); insufficiency (16-30 ng/mL); and deficiency (<16 ng/mL). In a second analysis, we included 63 patients with 25OHD<30 ng/mL with adjusted calcium levels below 10.2 mg/dL for treatment with oral calcidiol to approach target levels of 30 to 40 ng/mL. Mineral metabolism parameters were monitored at baseline as well as 6 and 12 months after beginning treatment. RESULTS: Insufficient or deficient 25OHD levels were present in 106/110 patients (96.3%); they were normal in just four patients (3.6%). Patients with calcidiol deficiency were older. We observed no differences in sex, posttransplant follow up, serum calcium, phosphate, iPTH, glomerular filtration rate, or 24- hour albuminuria or proteinuria. The 63 patients treated with oral calcidiol received a mean dose of 8044±4087 IU/wk at baseline. The 61.3% of them with deficient 25OHD levels at baseline decreased to 2.1% at 6 months and 7.5% at 12 months after treatment. No significant changes in calcium, phosphate or iPTH were observed during the treatment. CONCLUSIONS: Deficits of 25 OHD was frequent after renal transplantation but improved safely with moderate doses of oral calcidiol without negative secondary effects.

Genetic polymorphisms and individualized tacrolimus dosing.

BACKGROUND: Genetic polymorphisms of metabolism enzymes or intestinal drug transporters may affect pharmacokinetic responses to immunosuppressive drugs in renal transplant recipients. We sought to identify the frequency of genetic polymorphisms and their importance for individualization of tacrolimus doses. PATIENTS AND METHODS: We performed an observational study in 35 renal transplant recipients treated with tacrolimus, mycophenolate mofetil, and corticosteroids. Tacrolimus concentrations were determined by immunoanalysis (IMx method; Abbott Diagnostics, Abbott Park, Ill), on 11 blood samples per patient during the first 6 weeks after renal transplantation. For each patient, we calculated the mean value and its standard error (SEM) of the concentration/dose ratio (ng/mL/mg) of tacrolimus. The pharmacogenetic analysis included single nucleotide polymorphisms (SNPs) in the CYP3A5 (CYP3A5*3 (A6986G), CYP3A5*6 (G14690A), MDR1 (C3435T and G2677T/A) and PXR (C-25385T) genes. RESULTS: Of the patients, 62.8% (n=22) were men and the overall mean age was 55 years (95% confidence interval, 48.7-62.7). The SNP distribution was: CYP3A5*3: G/G=82.9%, A/G=17.1%; CYP3A5*6: G/G=88.6%, G/A=11.4%; MDR1 C3435T: C/C=25.7%, C/T=62.9%, T/T=11.4%; for MDR1 G2677T/A: G/G=22.9%, G/T=65.7%, T/T=11.4% and for PXR: C/T=85.7%, T/T=14.3%. Tacrolimus concentration/dose ratios in heterozygote patients for CYP3A5*3 genotypes was >120% lower than for the homozygote CYP3A5*3 genotype (0.65±0.04 vs 1.45±0.05; P<.0001). Wild-type MDR1 (3435 C/C) genotype patients showed up to 40% lower concentration/dose ratios compared with heterozygote and homozygote genotypes (C/C; 1±0.07 vs C/T; 1.4±0.06 vs T/T; 1.37±0.09; P<.0001). CONCLUSION: Intestinal absorption and metabolism of tacrolimus was significantly affected by the SNPs in the CYP3A5 and MDR1 genes, which may offer a useful tool to optimize tacrolimus dosing after renal transplantation.

[Strongyloides stercoralis infection in renal transplant recipients]. / Infección por Strongyloides stercoralis en pacientes trasplantados renales.

We present two cases of strongyloides stercoralis infection in renal transplant recipients in our centre. We describe clinical presentation characteristics, treatment and resolution.

Very low-grade proteinuria at 3 months posttransplantation is an earlier marker of graft survival.

Proteinuria is an early finding that appears in the first 3 months after transplantation in half of patients. Frequently, it is very low grade (VLP; <0.5 g/24 h). The aim of this study was to analyze the risk factors and prognostic significance of VLP at 3 months posttransplantation, which was maintained for the first year among our renal recipients. We compared 141 patients (39.7%) who showed VLP with 214 patients (60.3%) without proteinuria. VLP was associated with older recipients (P = .002), HLA incompatibilities (P = .001), older donors (P = .000), nontraumatic cause of brain death (P = .033) and previous hypertension (P = .030), tacrolimus (P = .000) and induction treatment with Thymoglobulin (P = .018) or anti-CD25 monoclonal antibodies (P = .000), as well as delayed graft function (DGF; P = .000). VLP patients showed worse renal function (P < .05) and greater requirement for antihypertensive drugs (P = .001). Multivariate analysis confirmed the impact of donor age, HLA incompatibilities, DGF, and tacrolimus treatment to predict the presence of VLP. Graft (P = .0019) and patient (P = .0146) survivals were lower among the VLP group. Cox analysis showed that VLP (RR: 2.047; P = .018) and DGF (RR: 2.062; P = .0017) were independently associated with reduced graft survival. The positive predictive value of VLP on graft survival was low. In conclusion, VLP was related to increasing acceptance of marginal donors, DGF, and worse renal function. Proteinuria was a noninvasive, readily determined parameter which was related to reduced graft and patient survivals, so renoprotective measures are mandatory from the early stages after transplantation.

Use of basiliximab induction in low-immunological risk renal transplant recipients receiving tacrolimus-based immunosuppression.

Basiliximab induction treatment has been shown to reduce the incidence of acute rejection episodes without the secondary side effects observed with antilymphocyte polyclonal antibodies. We analyzed our experience with basiliximab induction associated with tacrolimus-based immunosuppression among low-immunological risk renal transplant recipients. We retrospectively analyzed 55 renal transplantation patients of low inmunological risk who received organs from donors younger than 55 years. We compared a group of 21 patients (38.9%; group 1) treated with basiliximab (Simulect, Novartis, Basel, Switzerland) with 33 patients (61.1%; group 2) without induction. The patient groups did not differ in recipient age (46.39 +/- 11.1 in group 1 vs 41.82 +/- 11.02 years in group 2; P = .25), donor age (36.71 +/- 14.72 vs 35.09 +/- 14.63 years; P = .69), or recipient and donor gender. No differences were observed in dose or tacrolimus levels during follow-up. The incidences of delayed graft function (DGF; 28.6% vs 28.1%; P = .97) and of acute rejection episodes (9.5% vs 15.6%; P = .52) were similar in both groups. Serum creatinine and proteinuria levels (P > .05) and hospital admissions due to infections (36.4 vs 35.7%; P = .97) were also similar in both groups. At 1 year graft survival rates were 92% and 96% (P = .97) in groups 1 and 2, respectively. Considering our findings and the costs of basiliximab treatment, we conclude that routine administration of basiliximab cannot be justified in young, low-immunological risk transplant recipients undergoing tacrolimus-based immunosuppression.

[Analysis of variability in determining intact parathyroid hormone (iPTH) according to the method used to process the sample]. / Análisis de la variabilidad en la determinación de la hormona paratiroidea (PTH-i) según el método empleado para procesar la muestra.

BACKGROUND: The measurement of i-PTH circulating is not easy due to its analytical variablity. Variability that appears in the process that goes from the sample collection to the final result determination. There are several important aspects that can influence within the pre-test variability: type of sample (serum o plasma), temperature, time elapses from blood extraction to freezing and from freezing to i-PTH quantification. Blood coming from centres far from our laboratory do not always meet the required processing conditions. Our aim was to study the stability of i-PTH with varying conditions of temperature and time until freezing in patients with chronic kidney disease (CKD). METHODS: We have analyzed 294 blood samples of 49 patients with chronic kidney disease (18 transplantated patients (36.7%) and 31 patients in haemodyalisis (63.3%)). The blood samples were collected using tubes treated with ethylenediaminotetraacetic acid (EDTA); these samples were subjected to different conditions of temperature and time before they were frozen, constituting 6 groups: blood centrifuged and plasma immediately frozen (group A or reference group); blood maintained 1 hour at room temperature and plasma stored at 2-8 masculineC during 0, 8 and 24 hours (groups B,C,D); blood maintained 3 hours at room temperature and plasma stored at 2-8 masculineC during 0 and 8 hours (groups E,F). The intact PTH (i-PTH) was measured using the immunoradiometric assay (IRMA Total Intact Scantibodies assay). We have analyzed the differences between the PTH-i mean values in the referenced groud and the others. We have applied the tests of homogeneity variance and normality and we have perform a comparation by pairs with the t-test including the Bonferroni correction. RESULTS: The mean value of intact-PTH in the referente Group was 202.5+/-199.72 pg/ml. The means values of intact-PTH in the other groups were 196 +/- 203.23 pg/ml, 202.8 +/- 200.2 pg/ml, 200.06 +/- 194.87 pg/ml, 204.08 +/- 204.073 pg/ml, 197.94 +/- 182.31 pg/ml. The results were practically identical for each group. We did not find important differences with respect to the reference group (p = 0.87, p = 0,99, p = 0,95, p = 0,96, p = 0,90 when comparing with groups 2a, 2b, 2c, 3a y 3b). CONCLUSIONS: The use of EDTA maintain the PTH stability during a longer period without the necessity of freezing the samples immediately. These results can help to state strategies to management the samples in patients with ERC.