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1.
Br J Hist Sci ; 56(3): 351-368, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37548192

RESUMEN

Some experiments from the history of physics became so famous that they not only made it into the textbook canon but were transformed into lecture demonstration performances and student laboratory activities in the nineteenth and twentieth centuries. While, at first glance, some of these demonstrations as well as the related instruments do resemble their historical ancestors, a closer examination reveals significant differences both in the instruments themselves and in the practices and meanings associated with them. In this paper, I analyse the relation between the research instruments and the respective teaching demonstrations. In doing so, I particularly distinguish between demonstrations that address the process of the actual experimental procedures, and those that focus on the outcome or results (the product) of the experiment. This distinction will be illustrated in some exemplary case studies from the late nineteenth century and the early twentieth in which both the historical experiment and the related educational devices are analysed. The tension between the historical experiment on the one hand, and the different variants of the teaching version on the other, result in the educational as well as epistemological problems that are discussed in this paper.

2.
Artículo en Inglés | MEDLINE | ID: mdl-36069344

RESUMEN

Mass disasters are characterized by a disparity between health care demand and supply, which hampers complex therapies like kidney transplantation. Considering scarcity of publications on previous disasters, we reviewed transplantation practice during the recent COVID-19 pandemic, and dwelled upon this experience for guiding transplantation strategies in the future pandemic and non-pandemic catastrophes. We strongly suggest continuing transplantation programs during mass disasters, if medical and logistic operational circumstances are appropriate. Postponing transplantations from living donors and referral of urgent cases to safe regions or hospitals are justified. Specific preventative measures in anticipated disasters (such as vaccination programs during pandemics or evacuation in case of hurricanes or wars) may be useful to minimize risks. Immunosuppressive therapies should consider stratifying risk status and avoiding heavy immune suppression in patients with a low probability of therapeutic success. Discharging patients at the earliest convenience is justified during pandemics, whereas delaying discharge is reasonable in other disasters, if infrastructural damage results in unhygienic living environments for the patients. In the outpatient setting, telemedicine is a useful approach to reduce the patient load to hospitals, to minimize the risk of nosocomial transmission in pandemics and the need for transport in destructive disasters. If it comes down to save as many lives as possible, some ethical principles may vary in function of disaster circumstances, but elementary ethical rules are non-negotiable. Patient education is essential to minimize disaster-related complications and to allow for an efficient use of health care resources.

3.
Artículo en Inglés | MEDLINE | ID: mdl-36066915

RESUMEN

Mass disasters are characterized by a disparity between health care demand and supply, which hampers complex therapies like kidney transplantation. Considering scarcity of publications on previous disasters, we reviewed transplantation practice during the recent COVID-19 pandemic, and dwelled upon this experience for guiding transplantation strategies in the future pandemic and non-pandemic catastrophes. We strongly suggest continuing transplantation programs during mass disasters, if medical and logistic operational circumstances are appropriate. Postponing transplantations from living donors and referral of urgent cases to safe regions or hospitals are justified. Specific preventative measures in anticipated disasters (such as vaccination programs during pandemics or evacuation in case of hurricanes or wars) may be useful to minimize risks. Immunosuppressive therapies should consider stratifying risk status and avoiding heavy immune suppression in patients with a low probability of therapeutic success. Discharging patients at the earliest convenience is justified during pandemics, whereas delaying discharge is reasonable in other disasters, if infrastructural damage results in unhygienic living environments for the patients. In the outpatient setting, telemedicine is a useful approach to reduce the patient load to hospitals, to minimize the risk of nosocomial transmission in pandemics and the need for transport in destructive disasters. If it comes down to save as many lives as possible, some ethical principles may vary in function of disaster circumstances, but elementary ethical rules are non-negotiable. Patient education is essential to minimize disaster-related complications and to allow for an efficient use of health care resources.

4.
Ber Wiss ; 43(1): 7-27, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32176370

RESUMEN

Georg Simon Ohm's work in the field of electricity led to what is now considered to be the most fundamental law of electrical circuits, Ohm's Law. Much less known is that only months earlier, Ohm had published another law-one that differed significantly from the now accepted one. The latter entailed a logarithmic relation between the length of the conductor and a parameter that Ohm called "loss of force." This paper discusses how Ohm came up with an initial law that he felt compelled to correct a few months later. We analyze Ohm's publication as well as his laboratory notes, relating them to our own laboratory experiences while using the replication method to study his work. We also discuss the conceptual background of Ohm's work. We conclude that he was significantly influenced by French studies in the field of electricity, most notably the ones by Charles Augustin Coulomb.

5.
Clin Nephrol ; 88(8): 97-104, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28438256

RESUMEN

BACKGROUND: Acute interstitial nephritis (AIN) is a common cause of acute kidney injury that has not been adequately characterized in Sub-Saharan Africa (SSA) despite an increasing use of potentially inciting agents for the treatment of human immunodeficiency virus (HIV) and tuberculosis in the region. METHODS: A retrospective audit of records of patients with biopsy-proven AIN diagnosed at Groote Schuur Hospital, Cape Town from the 1st of January, 2006, to the 31st of December, 2015. RESULTS: 54 patients with biopsy-proven AIN were reviewed. The majority were of black African origin (59.2%), with HIV (42.8%) and HIV-tuberculosis coinfection (30.5%) as the most common comorbidities. Drug-related AIN was seen in 38 (67.9%) patients, with rifampicin as the most often implicated medication. Probable drug-related AIN was seen in 3 (5.4%) patients, infection-related AIN in 8 (14.3%), and unspecified causes in 4 (7.4%). AIN was suspected in 44.6% of patients before biopsy. 18 patients (34%) received hemodialysis, while 19 (35.2%) were treated with corticosteroids. Complete renal recovery at 30 and 90 days was seen in 23 (42.6%) patients and 24 (45.3%) patients, respectively, with the majority seen among those with drug-induced AIN. Six (11.1%) patients died; 4 (10.5%) of the patients were in the drug-related group. There was no correlation between degree of interstitial inflammation and severity of renal failure (p = 0.10). On multivariate logistic regression, drug-related causes of AIN were predictive of complete recovery at day 30 (OR 16.63; 95% CI: 1.71 - 161.6, p = 0.02), and presence of interstitial fibrosis reduced likelihood of recovery (OR 0.03; 95% CI 0.002 - 0.46, p = 0.012). Steroid use did not influence partial recovery (OR 0.59, 95% CI 0.17 - 1.77; p = 0.32) or complete recovery (OR 3.38, 95% CI 0.38 - 30.39, p = 0.28). CONCLUSIONS: AIN is common in patients with HIV or those on treatment for tuberculosis. Drug-related AIN is often associated with improved outcomes. This is particularly reassuring in the SSA region where the use of potentially-inciting medications is rife from a high burden of HIV and tuberculosis.
.


Asunto(s)
Riñón/patología , Nefritis Intersticial/terapia , Enfermedad Aguda , Adulto , Biopsia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nefritis Intersticial/epidemiología , Nefritis Intersticial/etiología , Nefritis Intersticial/patología , Estudios Retrospectivos
6.
Clin Nephrol ; 88(1): 27-32, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28427496

RESUMEN

BACKGROUND: Mortality of critically-ill patients with acute kidney injury (AKI) requiring renal replacement therapy (RRT) in an intensive-care setting continues to remain high. There is still uncertainty as to which factors should guide clinical judgement. METHODS: A cohort of 155 patients admitted to an intensive-care unit and necessitating RRT due to AKI were retrospectively analyzed. Demographic and clinical parameters at the time of RRT initiation were retrieved. Multi- and univariate analyses were performed to determine the impact of different risk factors on mortality. RESULTS: The most common causes of AKI were sepsis (39.3%) and cardiac events (32%). The majority of patients were treated by continuous (67.3%), the others by intermittent RRT. After 30 days, 51.0% of patients survived. Nonsurvivors were older (73 vs. 69 years), had a higher APACHEE II score (30.1 ± 5.6 vs. 26.5 ± 7.1), and were more likely to be vasopressor dependent, mechanically ventilated, or treated by continuous RRT. Multivariate analysis revealed that higher age, higher APACHEE II score, and lower serum creatinine at baseline were independent predictors for mortality, whereas histories of diabetes mellitus, arterial hypertension, coronary heart disease, or stroke were not. CONCLUSION: Critically-ill patients with AKI requiring RRT continue to have a high mortality. Age and APACHE II score showed an impact on mortality whereas traditional cardiovascular risk factors did not. Higher BUN and creatinine levels do not have a negative impact on mortality. Our findings support the current practice that RRT initiation should primarily be guided by clinical decision.
.


Asunto(s)
Lesión Renal Aguda/mortalidad , Unidades de Cuidados Intensivos , Terapia de Reemplazo Renal , Lesión Renal Aguda/terapia , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
7.
Nephrol Dial Transplant ; 31(8): 1327-34, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26442902

RESUMEN

BACKGROUND: Although citrate dialysate (CiDi) is regarded to be safe, dialysis modalities using higher dialysate volumes, like haemodiafiltration (HDF), may expose patients to higher citrate load and thus increase the risk of complications. We investigated the residual risk of CiDi compared with standard dialysate (StDi) in patients on different dialysis modalities and its effect on dialysis dose. METHODS: In a multicentre randomized crossover study, 92 dialysis patients (HDF post-dilution: n = 44, HDF pre-dilution: n = 26, haemodialysis: n = 25) were treated for 4 weeks with each dialysate (StDi and CiDi). Hypocalcaemia (ionized calcium ≤0.9 mmol/L), alkalosis (pH ≥7.55), post-treatment bicarbonate ≥32 mmol/L, pre-treatment bicarbonate ≥27 mmol/L, intra-dialytic events (IEs) and adverse events (AEs) between dialysis sessions were investigated as primary end points. The secondary objective was dialysis efficacy, i.e. dose and removal ratios of urea, creatinine, phosphate and ß-2-microglobulin. RESULTS: Post-dialysis overcorrection of bicarbonate (>32 mmol/L) was less frequent with CiDi (P = 0.008). Other predefined calcium and acid-base disturbances did not vary. There was no significant difference in IE. However, more patients developed AEs such as fatigue, muscle spasms or pain using CiDi (StDi: 41 versus CiDi: 55 patients, P = 0.02), particularly in the first 2 weeks of exposure. Dialysis efficacy was comparable with both dialysates. CONCLUSIONS: It can be confirmed that CiDi is not associated with the development of severe calcium and acid-base disorders, even when dialysis modalities with higher citrate loads are used. However, a refinement of the CiDi composition to minimize AEs is necessary.


Asunto(s)
Ácido Cítrico/farmacología , Soluciones para Diálisis/farmacología , Hipercalcemia/prevención & control , Fallo Renal Crónico/terapia , Diálisis Renal/métodos , Adulto , Anciano , Quelantes del Calcio/farmacología , Estudios Cruzados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
9.
Am J Physiol Renal Physiol ; 302(12): F1663-73, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-22442208

RESUMEN

Interleukin-17A (IL-17) promotes inflammatory renal tissue damage in mouse models of crescentic glomerulonephritis, including murine experimental autoimmune anti-myeloperoxidase glomerulonephritis, which most likely depends on IL-17-producing Th17 cells. In human anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis, however, the cellular sources of IL-17 remain to be elucidated. Therefore, we analyzed human kidney biopsies of active necrotizing and crescentic ANCA-associated glomerulonephritis by immunohistochemistry using an IL-17-specific antibody and by immunofluorescent colocalization with cell type markers. We detected numerous IL-17-expressing (IL-17(+)) cells in the glomeruli and in the tubulointerstitium. Unexpectedly, most of these IL-17(+) cells were polymorphonuclear neutrophilic granulocytes, while IL-17(+) T cells and IL-17(+) mast cells were present at significantly lower frequencies. IL-17 was not detected in other infiltrating or resident kidney cells. In those patients who had not received immunosuppressive treatment before biopsy, serum creatinine levels were positively correlated with tubulointerstitial IL-17(+) neutrophils as well as IL-17(+) T cells. Furthermore, we could demonstrate that purified human blood neutrophils expressed IL-17 protein and released it upon stimulation in vitro. In conclusion, these results support a pathogenic role for IL-17 in human ANCA-associated glomerulonephritis. Our data suggest that in the acute stage of the disease neutrophils may act as an important immediate-early innate source of IL-17 and may thereby initiate and promote ongoing renal inflammation. IL-17 may thus be a target for treating acute ANCA-associated glomerulonephritis.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/metabolismo , Glomerulonefritis/metabolismo , Interleucina-17/metabolismo , Riñón/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Anticitoplasma de Neutrófilos/inmunología , Femenino , Glomerulonefritis/inmunología , Humanos , Riñón/inmunología , Masculino , Mastocitos/inmunología , Mastocitos/metabolismo , Persona de Mediana Edad , Neutrófilos/inmunología , Neutrófilos/metabolismo
10.
Med Klin Intensivmed Notfmed ; 117(5): 367-373, 2022 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-34191045

RESUMEN

About 50% of all critically ill patients develop acute kidney injury (AKI) and approximately 15% receive renal replacement therapy (RRT). Although RRT is frequently used in intensive care units in Germany, it is currently unknown which RRT procedures are available, which qualification the involved staff has, which anticoagulation strategies are used and how RRT doses are prescribed. To investigate quality and structural characteristics of the performance of RRT in intensive care units throughout Germany, the German Interdisciplinary Society of Intensivists (Deutsche Interdisziplinäre Vereinigung für Intensiv- und Notfallmedizin [DIVI]) performed an inquiry among their members. A total of 897 members participated in the survey in which practical aspects were queried. In 69.1% of the cases, RRT was performed in hospitals with more than 400 beds and in 74.5% in university hospitals or other primary care hospitals. Furthermore, 93.3% of clinics are equipped with continuous and 75.8% with intermittent renal replacement devices. In 91.9%, indication for initiation of RRT was performed by trained physicians specialized in intensive care medicine or nephrologists. Intermittent as well as continuous modalities are both present in three-quarters of cases, which allows for individualized therapy. However, the documentation of dialysis dose needs to be improved.


Asunto(s)
Lesión Renal Aguda , Terapia de Reemplazo Renal , Lesión Renal Aguda/terapia , Cuidados Críticos , Humanos , Unidades de Cuidados Intensivos , Diálisis Renal/métodos , Terapia de Reemplazo Renal/métodos
11.
Transplant Rev (Orlando) ; 36(4): 100726, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36113305

RESUMEN

Due to the shortage of deceased and genetically- or emotionally-related living donors, living unrelated paid donor (LURpD) kidney transplantation has been considered; however, this practice may result in medical, ethical and social dilemmas, induce organ trading (commodification), and even criminal activities. Commodification also risks undermining public trust in the transplant system and impeding the development of proper altruistic or deceased donor programs by ignoring altruism, volunteerism, and dignity. However, despite many objections by authoritative organizations, black market practices are involved in up to 10% of all transplants worldwide. The authors strongly discourage any payment or rewards for organ donation, and instead urge the governments of all countries to provide adequate and accessible kidney health care. However, it is an undeniable fact that paid-living donor transplantation is increasing despite all objections, disapprovals and regulations. We feel it as our responsibility not to ignore this uncertain and undesirable practice, but rather to underline the necessity for strict rules and prohibitions to minimize unacceptable medical, social and ethical risks as long as it exists. Furthermore, economic profit, be it direct or indirect, must not be the goal of those involved, and the employment of intermediaries must be avoided entirely. Additionally, the donor should be in a position where not donating has no detrimental effect on his/her future in any way (free agency). In our view, every country has the obligation and responsibility to provide adequate kidney health care and to make kidney transplantation accessible to those in need. This provision is key to stop transplant tourism and commercialization of kidney transplantation. The nephrology community has a duty to establish structures that optimize organ availability within strict ethical limits. The legal position of LURpD varies considerably worldwide. Strictly respecting each country's legislation and local values is mandatory to minimize medical and ethical risks and controversies.


Asunto(s)
Trasplante de Riñón , Trasplante de Órganos , Obtención de Tejidos y Órganos , Femenino , Humanos , Masculino , Donadores Vivos , Riñón
12.
Kidney Int ; 79(11): 1236-43, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21368745

RESUMEN

Primary focal segmental glomerulosclerosis (FSGS) is a disease with poor prognosis and high unmet therapeutic need. Here, we evaluated the safety and pharmacokinetics of single-dose infusions of fresolimumab, a human monoclonal antibody that inactivates all forms of transforming growth factor-ß (TGF-ß), in a phase I open-label, dose-ranging study. Patients with biopsy-confirmed, treatment-resistant, primary FSGS with a minimum estimated glomerular filtration rate (eGFR) of 25 ml/min per 1.73 m(2), and a urine protein to creatinine ratio over 1.8 mg/mg were eligible. All 16 patients completed the study in which each received one of four single-dose levels of fresolimumab (up to 4 mg/kg) and was followed for 112 days. Fresolimumab was well tolerated with pustular rash the only adverse event in two patients. One patient was diagnosed with a histologically confirmed primitive neuroectodermal tumor 2 years after fresolimumab treatment. Consistent with treatment-resistant FSGS, there was a slight decline in eGFR (median decline baseline to final of 5.85 ml/min per 1.73 m(2)). Proteinuria fluctuated during the study with the median decline from baseline to final in urine protein to creatinine ratio of 1.2 mg/mg with all three Black patients having a mean decline of 3.6 mg/mg. The half-life of fresolimumab was ∼14 days, and the mean dose-normalized Cmax and area under the curve were independent of dose. Thus, single-dose fresolimumab was well tolerated in patients with primary resistant FSGS. Additional evaluation in a larger dose-ranging study is necessary.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Glomeruloesclerosis Focal y Segmentaria/tratamiento farmacológico , Riñón/efectos de los fármacos , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Adulto , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales Humanizados , Biomarcadores/orina , Biopsia , Creatinina/orina , Relación Dosis-Respuesta a Droga , Europa (Continente) , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Glomeruloesclerosis Focal y Segmentaria/inmunología , Glomeruloesclerosis Focal y Segmentaria/patología , Glomeruloesclerosis Focal y Segmentaria/fisiopatología , Humanos , Infusiones Parenterales , Riñón/inmunología , Riñón/patología , Riñón/fisiopatología , Masculino , Persona de Mediana Edad , Proteinuria/tratamiento farmacológico , Proteinuria/inmunología , Factor de Crecimiento Transformador beta/inmunología , Resultado del Tratamiento , Estados Unidos , Adulto Joven
13.
Nephrol Dial Transplant ; 26(1): 232-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20876598

RESUMEN

BACKGROUND: Continuous venovenous haemofiltration (CVVH) in the intensive care setting requires anticoagulation to prevent clotting of the extracorporeal circuit. Several protocols avoiding heparin and using regional citrate anticoagulation have been developed to diminish bleeding risks. However, data from randomized trials comparing citrate anticoagulation with systemic heparinization are very limited. METHODS: One hundred and seventy-four patients on mechanical ventilation, requiring renal replacement therapy for acute renal failure, were included in this prospective randomized multicentre trial comparing regional citrate with systemic heparin. The study was performed at nine different intensive care units at university or academic teaching hospitals. The participants were randomized to either CVVH using regional citrate anticoagulation or CVVH using systemic anticoagulation with unfractionated heparin. The primary outcome was to compare treatment efficacy represented by the patients' acid base status on Day 3 and on each consecutive day. Several parameters of safety and efficacy were analysed as secondary outcomes. RESULTS: Comparison of standard bicarbonate from Day 3 to Day 11 revealed no difference between both treatment modalities. Use of citrate resulted in less systemic anticoagulation, a lower risk of bleeding and a longer haemofilter patency. Episodes of hypercalcaemia, hypocalcaemia and the need for additional bicarbonate infusions occurred more often under citrate. The patients' high mortality was not influenced by the mode of anticoagulation. CONCLUSIONS: Citrate may be used as a regional anticoagulant and the only buffering agent in CVVH with adequate treatment efficacy and safety. However, neither citrate nor heparin anticoagulation should be regarded as a therapeutic standard, since there is no advantage of one of these substances with regard to patient mortality.


Asunto(s)
Lesión Renal Aguda/terapia , Anticoagulantes/uso terapéutico , Citratos/uso terapéutico , Enfermedad Crítica , Hemofiltración , Heparina/uso terapéutico , Anciano , Bicarbonatos/uso terapéutico , Tampones (Química) , Femenino , Hemorragia/etiología , Hemorragia/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Diálisis Renal , Tasa de Supervivencia , Resultado del Tratamiento
14.
Nephrology (Carlton) ; 16(8): 730-5, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21777344

RESUMEN

AIM: We evaluated the influence of C-344T polymorphism of the aldosterone synthase gene, associated with aldosterone levels and the development of arterial hypertension, on focal segmental glomerulosclerosis (FSGS). METHODS: We studied 81 patients with primary FSGS followed up for 8.0 ± 12 years. Patients were classified according to their slope of reciprocal serum creatinine into group A (slow progressors, n = 57) and B (fast progressors, n = 24). One hundred healthy volunteers were analysed as controls. The biopsies of n = 50 patients were reviewed and analysed by the same pathologist. C-344T polymorphism was determined by polymerase chain reaction. RESULTS: The allele frequencies differed significantly between patients (C-allele: 0.55, T-allele: 0.45) and controls (C-allele: 0.45, T-allele: 0.55; P < 0.05). Patients carrying the C-allele tended to have a higher percentage of sclerosed glomeruli (41.8 ± 30% vs 31. 2 ± 19% in TT genotype, ns) and tubulointerstitial fibrosis (22.8 ± 18% vs 16.0 ± 5%, ns). The rate of deterioration of renal function was higher in the CC/CT genotypes (-0.216 ± 0.449 dL/mg per year) compared to the TT genotype (-0.030 ± 0.041 dL/mg per year, P = 0.002). Furthermore, 36.4% of the C-allele carriers and none of the patients with the TT genotype belonged to group B (P = 0.005). C-allele carriers also had a worse kidney survival in the Kaplan-Meier analysis (P = 0.027). CONCLUSION: Our results indicate that aldosterone synthase gene C-344T polymorphism not only acts as a risk factor for the development of FSGS, but also may influence its pathologic appearance and could serve as a marker of disease progression.


Asunto(s)
Citocromo P-450 CYP11B2/genética , Glomeruloesclerosis Focal y Segmentaria/genética , Polimorfismo Genético , Adulto , Progresión de la Enfermedad , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/epidemiología , Predisposición Genética a la Enfermedad/genética , Genotipo , Glomeruloesclerosis Focal y Segmentaria/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Adulto Joven
15.
Ren Fail ; 33(4): 393-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21476902

RESUMEN

AIM: In the past years, aldosterone has been identified as an important mediator of renal injury. In this study, we evaluated the influence of C-344T polymorphism of aldosterone synthase gene, associated with serum aldosterone levels and the development of arterial hypertension, on IgA nephropathy (IgAN). METHODS: We studied n = 143 patients with biopsy-proven IgAN followed up for 7.1 ± 6.2 years. Patients were classified according to the slope of reciprocal serum creatinine into group A (slow progressors, n = 93) and group B (fast progressors, n = 50). One hundred healthy volunteers were analyzed as controls. The biopsies of n = 79 patients were reviewed and analyzed by the same pathologist. Aldosterone synthase gene C-344T polymorphism was determined by polymerase chain reaction amplification. RESULTS: The genotype distribution was similar in patients and control subjects [not significant (ns)]. Age, initial renal function, proteinuria, and blood pressure did not differ significantly between patients with different genotypes (ns). The percentage of sclerosed glomeruli tended to be higher among patients carrying the CC/CT genotypes (29.4 ± 26.5% vs. 21.7 ± 25.2% in TT genotype; ns). C-344T polymorphism was associated with the progression of IgAN as shown by the different genotype frequencies in group Α (slow progressors, CC/CT: 60.2%, TT: 39.8%) and group B (fast progressors, CC/CT: 78.0%, TT: 22:0%; p = 0.032). CONCLUSION: Our results indicate that aldosterone synthase gene C-344T polymorphism is a risk factor for accelerated progression in Caucasian patients with IgAN.


Asunto(s)
Aldosterona/sangre , Citocromo P-450 CYP11B2/genética , Glomerulonefritis por IGA/genética , Hipertensión/etiología , Adulto , Biopsia , Progresión de la Enfermedad , Femenino , Genotipo , Glomerulonefritis por IGA/complicaciones , Glomerulonefritis por IGA/metabolismo , Glomerulonefritis por IGA/patología , Humanos , Riñón/patología , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Adulto Joven
16.
Am J Kidney Dis ; 55(2): 259-68, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20042261

RESUMEN

BACKGROUND: There are few anecdotal reports of circulating antineutrophil cytoplasmic autoantibodies (ANCAs) in patients with immunoglobulin A (IgA) nephropathy. STUDY DESIGN: Retrospective case series. SETTING & PARTICIPANTS: We studied 8 patients with crescentic IgA nephropathy associated with ANCAs against myeloperoxidase (n = 5) and proteinase 3 (n = 3) followed up for 2.4 +/- 1.7 years. They were compared with 26 patients with IgA nephropathy with > 10% crescentic glomeruli, but negative for ANCAs. OUTCOMES: We analyzed clinical and histologic features of patients and their response to treatment. MEASUREMENTS: Screening for ANCAs was performed using indirect immunofluorescence, and positive results were verified using enzyme-linked immunosorbent assay. RESULTS: All patients with crescentic IgA nephropathy and positive for ANCAs, compared with only one-third of ANCA-negative patients, presented with the clinical syndrome of rapid progressive glomerulonephritis. ANCA-positive patients reached a higher peak serum creatinine level within the first 3 months (4.2 +/- 2.2 vs 2.5 +/- 1.9 mg/dL; estimated glomerular filtration rate, 19.3 +/- 10.2 vs 45.9 +/- 30.1 mL/min/1.73 m(2)). ANCA-positive patients with IgA nephropathy had a higher percentage of crescentic glomeruli (54.3% +/- 18%) compared with ANCA-negative patients with crescentic IgA nephropathy (34.5% +/- 26%). ANCA-positive patients were treated using cyclophosphamide and corticosteroids. Kidney function improved in all these patients: serum creatinine level decreased from the peak of 4.2 +/- 2.2 to 1.7 +/- 0.7 mg/dL at the end of follow up (estimated glomerular filtration rate, 19.3 +/- 10.2 to 44.6 +/- 11.1 mL/min/1.73 m(2)). In contrast, no significant improvement was achieved in ANCA-negative patients. CONCLUSION: Patients with IgA nephropathy, crescents, and positive for ANCAs represent a clinical entity with a diverse more exaggerated clinical and histologic picture. However, disease in these patients responded well to aggressive immunosuppressive therapy.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/sangre , Glomerulonefritis por IGA/sangre , Adulto , Femenino , Glomerulonefritis por IGA/clasificación , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
17.
Med Klin Intensivmed Notfmed ; 115(7): 566-570, 2020 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-33025048

RESUMEN

Renal replacement therapy is after mechanical ventilation one of the most important and frequently used organ replacement therapies in daily routine intensive care practice. In contrast to mechanical ventilation, quality standards for renal replacement therapy are less well known and defined. In this position paper of the German Interdisciplinary Association for Intensive Care and Emergency Medicine, we describe quality standards of renal replacement procedures in order to improve therapy of patients with severe acute kidney injury.


Asunto(s)
Lesión Renal Aguda , Enfermedad Crítica , Lesión Renal Aguda/terapia , Cuidados Críticos , Enfermedad Crítica/terapia , Humanos , Mejoramiento de la Calidad , Terapia de Reemplazo Renal
18.
Nephrol Dial Transplant ; 24(9): 2847-51, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19349293

RESUMEN

BACKGROUND: Inflammation is a well recognized central component of atherosclerotic processes in chronic kidney disease. Interleukin-6 (IL-6) levels are a strong determinant of cardiovascular mortality in dialysis patients. We evaluated the impact of IL-6 gene G-174C polymorphism associated with modified IL-6 production on the development of coronary artery disease (CAD), cardiovascular events and mortality in chronic dialysis patients. METHODS: We studied n = 463 patients on chronic dialysis with angiographically confirmed (n = 218) or excluded (n = 245) CAD followed up for 65 months after initiation of dialysis. Monitored were arterial hypertension, diabetes mellitus, hyperlipidemia, smoking, CRP and fibrinogen. IL-6 gene G-174C polymorphism was determined by PCR amplification. RESULTS: The CC genotype was associated with an impaired patient survival (p < 0.05) remaining an independent risk factor for death in multivariate analysis (HR for CC genotype: 3.58, CI: 1.41-9.07, p < 0.01). CC genotype carrying CAD patients suffered significant frequently cardiovascular events (revascularization, myocardial infarction, death) compared to GG/GC genotype carriers (85.2% vs. 66.5, p < 0.05). However, the IL-6 gene G-174C polymorphism was not related to the onset and development of CAD itself (ns) and the inflammation parameters CRP and fibrinogen did not differ between the genotypes under investigation (ns). CONCLUSIONS: Our results suggest that IL-6 gene G-174C polymorphism is associated with the incidence of cardiovascular events and mortality in chronic dialysis patients.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/genética , Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/genética , Interleucina-6/genética , Fallo Renal Crónico/genética , Fallo Renal Crónico/terapia , Polimorfismo de Nucleótido Simple , Diálisis Renal , Anciano , Secuencia de Bases , Enfermedades Cardiovasculares/mortalidad , Enfermedad de la Arteria Coronaria/mortalidad , Cartilla de ADN/genética , Femenino , Genotipo , Humanos , Mediadores de Inflamación/metabolismo , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/etiología , Infarto del Miocardio/genética , Infarto del Miocardio/mortalidad , Diálisis Renal/efectos adversos , Diálisis Renal/mortalidad
19.
Dtsch Med Wochenschr ; 144(3): 171-174, 2019 02.
Artículo en Alemán | MEDLINE | ID: mdl-30703835

RESUMEN

Acute kidney injury (AKI) can be considered as an inflammatory systemic disorder affecting virtually every organ. It has great impact on morbidity and mortality of critically ill patients. DIAGNOSTIC: The use of electronic alerts for detection of AKI combined with the use of standardized kidney care bundles can improve patient outcomes. Currently, it is important to find ways to implement these in everyday clinical practice. PREVENTION/CONSERVATIVE THERAPY: Volume replacement therapy should always be carried out with balanced solutions. The use of 0.9 % NaCl solution should be avoided. In individual cases, patients can also benefit from a colloidal solution in the form of human albumin. Urgently indicated radiographic diagnosis with iodine-containing contrast agent should not be delayed or canceled due to renal impairment. The prophylactic measures in this context are not different from the general recommendations in AKI (achieve euvolemia, avoid nephrotoxins), specific measures do not exist. Indiscriminate hydration of non-hypovolemic patients has no advantages and is associated with an increased risk of cardiac decompensation and AKI. RENAL REPLACEMENT THERAPY: Treatment dose and modality should be adapted to the clinical needs of the patient. The recommended dose of 20 - 25 ml/kg/h serves as orientation. Continuous and intermittent therapies should be available. Regional citrate anticoagulation (RCA) can also be safely used for patients with liver damage or lactic acidosis, provided that early signs of citrate accumulation are closely monitored. In the case of lactic acidosis, lactate clearance rather than baseline level of lactate is particularly important for the risk of citrate accumulation.


Asunto(s)
Lesión Renal Aguda , Cuidados Críticos , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/fisiopatología , Lesión Renal Aguda/terapia , Enfermedad Crítica , Humanos , Unidades de Cuidados Intensivos , Terapia de Reemplazo Renal
20.
BMJ Open ; 9(8): e029001, 2019 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-31462473

RESUMEN

OBJECTIVES: The International Society of Nephrology (ISN) has called for zero deaths by 2025. This survey aimed to determine the preparedness of Southern African Development Community (SADC) countries and Nigeria to heed this call. SETTING: A questionnaire was emailed to facilities, where renal replacement therapy is available; to determine type of services available; quality of care and identify clinicians involved. PARTICIPANTS: Clinicians and administrators involved in the care of patients with acute kidney injury (AKI) completed the questionnaire. RESULTS: Completed questionnaires were received from 12 of the 15 SADC countries and Nigeria, covering 48 service providers. The government provided partial funding for dialysis in 41.7% of services. There was no funding for acute dialysis in two countries. Interdisciplinary teams in 72.9% of hospitals covered the intensive care units (ICUs), which included at least one nephrologist in 75%. Only 77% were able to provide dialysis in ICU. Intermittent haemodialysis was the most common modality available (91.7% of facilities), sustained low-efficiency dialysis in 50%, continuous therapies in 35% and peritoneal dialysis in 33.3%. Almost half (47.9%) of the sites were limited to one mode of dialysis and unable to care for severely ill patients. The clinical status was used to initiate and monitor dialysis, with very few sites having clear written standard operating procedures. CONCLUSION: In the 16 countries surveyed, the majority had limited ability to provide comprehensive dialysis programmes for patients with AKI due to lack of facilities and government funding. Additionally, nephrologists are scarce; modes of dialysis are limited; as is the care for severely ill patients and lack of standard operating procedures. Resources, training and funding need to be made available to create universal coverage of dialysis for AKI. The ISN goal of providing renal replacement therapy to all by 2025 is unlikely to be achieved in SADC and Nigeria.


Asunto(s)
Lesión Renal Aguda/terapia , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Grupo de Atención al Paciente/estadística & datos numéricos , Terapia de Reemplazo Renal/estadística & datos numéricos , África del Sur del Sahara , Terapia de Reemplazo Renal Continuo/estadística & datos numéricos , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Terapia de Reemplazo Renal Intermitente/estadística & datos numéricos , Nigeria , Gravedad del Paciente , Diálisis Peritoneal/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Terapia de Reemplazo Renal/economía , Encuestas y Cuestionarios
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