ABSTRACT Objective: Encapsulating peritoneal sclerosis (EPS) is a rare, but potentially fatal complication of peritoneal dialysis. Currently, treatment of peritoneal fibrosis is not fully possible yet. In this study, we aimed to demonstrate the effects of tacrolimus therapy on peritoneal fibrosis and inflammation when administered alone or with mycophenolate mofetil (MMF) in the EPS model induced in rats. Methods: Thirty six Wistar albino rats were separated into six equal groups. Group I was the control group. Group II-VI were administered intraperitoneal chlorhexidine (CH) for induced EPS model in rats. Group II, IV, V, VI were administered isotonic liquid, tacrolimus, tacrolimus and concurrently with CH, tacrolimus and MMF together, respectively. Group III was not administered any drug. All peritoneal samples were stained immunohistochemically with matrix metalloproteinase-2 (MMP-2) antibody. Thickness of peritoneal fibrosis, subserosal large collagen fibers, subserosal fibroblast proliferation and subserosal fibrotic matrix deposition were evaluated. Results: Comparing the experimentally induced EPS groups, the best histopathological results and the largest staining with MMP-2 were achieved in Group VI. Furthermore, in all treatment groups (IV, V, VI) more staining with MMP-2 was detected compared to non-treatment groups (I, II, III) but no statistically significant differences were found among all groups. A statistically significant remission was observed in all histopathological parameters, primarily peritoneal thickness in rats that were administered MMF with tacrolimus, compared to rats which were administered tacrolimus only. Conclusion: Concurrent use of tacrolimus and MMF in the treatment of EPS may be a promising approach.

RESUMEN Objetivos: La esclerosis peritoneal encapsulante (EPE) es una complicación rara, peropotencialmente fatal de la diálisis peritoneal. Actualmente, el tratamiento de la fibrosis peritoneal aún no es posible. En este estudio, apuntamos a demostrar los efectos de la terapia con tacrolimus en la fibrosis peritoneal y la inflamación cuando se administran solos o con micofenolato de mofetilo (MMF) en el modelo EPE inducido en ratas. Métodos: Treinta y seis ratas Wistar albinas se separaron en seis grupos iguales. El Grupo I era el grupo de control. En los grupos II-VI se administró clorhexidina intraperitoneal (CH) para el modelo EPE inducido en ratas. En los Grupos II, IV, V, VI se administró respectivamente líquido isotónico, tacrolimus, tacrolimus y CH y finalmente tacrolimus y MMF juntos. El grupo III no recibió ningún medicamento. Todas las muestras peritoneales se tiñeron inmunohistoquímicamente con el anticuerpo Matrix Metaloproteinasa-2 (MMP- 2). Se evaluó el grosor de la fibrosis peritoneal, se evaluaron las fibras de colágeno grandes subserosas, la proliferación de fibroblastos subserosa y la deposición de la matriz fibrótica subserosa. Resultados: Comparando los grupos de EPE inducidos experimentalmente, los mejores resultados histopatológicos y la tinción con MMP- 2 más extensa se lograron en el Grupo VI. Además, en todos los grupos de tratamiento (IV, V, VI) se detectó más tinción con MMP-2 en comparación con los grupos de no tratamiento (I, II, III), pero no se encontraron diferencias estadísticamente significativas entre todos los grupos. Se observó una remisión estadísticamente significativa en todos los parámetros histopatológicos, principalmente el espesor peritoneal en ratas que recibieron MMF con tacrolimus, en comparación con las ratas que recibieron solo tacrolimus. Conclusión: El uso concurrente de tacrolimus y MMF en el tratamiento de EPS puede ser una aplicación prometedora.

ABSTRACT Background: Steroids are the mainstream drugs of immu- nosuppressive regimen in renal transplantation. They are successfully used on induction, maintenance and rejection treatment. Due to complications caused by steroids, treatments are switched to immunosuppressive agents. Graft dysfunction risk caused by reduced total immunosuppression disturbs clinicians very often. We documented the differences among patients by means of clinical presentation and PRA/DSA levels between patients who are using steroids and patients that were prescribed for steroid-free regimen. Methods: 82 individuals who did not use steroid and 52 patients on steroid treatment were included with similar rates of age, sex, primary renal disease, dialysis type, posttransplant follow-up duration and donor type. Pre and posttransplant PRA, DSA levels, posttransplant and current graft function and comorbidities were evaluated. Results: Individuals who do not use steroids were found to have a lower posttransplant creatinine level and glomerular filtration rate (GFR) compared to steroid users. Posttransplant and current spot urinary protein/creatinine rates were also lower in the steroid-free group. However DM, BKVN and induction therapy rates were higher in the steroid-free group. PRA and DSA levels were similar in both groups. On the other hand, posttransplant PRA-I levels were significantly higher in those with less steroid use time. Conclusions: Although steroid free regimens usually worry the clinicians, they can be preferred in patients with low immunological risk for rejection to avoid its side effects such as uncontrolled diabetes, obesity, musculoskeletal problems and cataracts.

RESUMEN Antecedentes: Los esteroides son los principales fármacos del régimen inmunosupresor en el trasplante renal. Se utilizan con éxito en tratamientos de inducción, mantenimiento y rechazo. Debido a las complicaciones causadas por los esteroides, los tratamientos se cambian a agentes inmunosupresores. El riesgo de disfunción del injerto causado por la reducción de la inmunosupresión total perturba a los médicos con mucha frecuencia. Documentamos la diferencia entre los pacientes por medio de la presentación clínica y los niveles de PRA/DSA en aquellos que utilizan esteroides y a los que se les prescribió un regimen sin esteroides. Material y métodos: Se incluyeron 82 individuos que no usaban esteroides y 52 pacientes en tratamiento con esteroides con tasas similares de edad, sexo, enfermedad renal primaria, tipo de diálisis, duración del seguimiento postrasplante y tipo de donante. Se evaluaron la ARP pre y postrasplante, los niveles de DSA, la función y comorbilidades postrasplante y actual del injerto. Resultados: Se encontró que las personas que no usan esteroides tienen un nivel de creatinina postrasplante y una tasa de filtración glomerular (TFG) más bajas en comparación con los usuarios de esteroides. Las tasas de proteína/creatinina urinarias postrasplante y puntuales actuales también fueron más bajas en el grupo sin esteroides. Sin embargo, las tasas de DM, BKVN y terapia de inducción fueron más altas en el grupo sin esteroides. Los niveles de PRA y DSA fueron similares en ambos grupos. Por otro lado, los niveles de PRA-I postrasplante fueron significativamente más altos en aquellos con menos tiempo de uso de esteroides. Conclusiones: Aunque los regimenes libres de esteroides suelen preocupar a los clínicos, pueden ser preferidos en pacientes con bajo riesgo inmunológico de rechazo para evitar sus efectos secundarios, como diabetes no controlada, obesidad, problemas musculoesqueléticos y cataratas.

Summary Objective: Arterial stiffness refers to arterial wall rigidity, particularly developing in central vessels. Arterial stiffness increases in early stage chronic kidney disease (CKD), and it is a strong predictor of cardiovascular and all cause mortality. Vitamin D has beneficial effects on blood pressure, vascular endothelial function and arterial stiffness. 25-hydroxyvitamin D (25(OH)D) deficiency is quite common worldwide and in the CKD population. We aimed to evaluate the prevalence of 25(OH)D deficiency and its relation with arterial stiffness in CKD. Method: Our study included 101 patients (51 male, 50 female), with stages 3B-5 CKD not on dialysis. A single-cuff arteriograph device (Mobil-O-Graph) was used to evaluate arterial stiffness parameters of pulse wave velocity (PWV) and augmentation index (Alx@75). The patients were divided into two groups: group I vitamin D non-deficient [25(OH)D > 15 ng/mL] and group II vitamin D deficient [25(OH)D ≤ 15 ng/mL]. Results: Overall, the mean 25(OH)D level was 14.1±7.9 ng/mL and 70 patients (69.4%) were vitamin D deficient. The mean Alx@75 value was significantly higher in group II (28.6±10.8% vs. 23.3±13.5%, p=0.038). PWV was higher in group II, but the difference was not significant. Group II exhibited significantly lower serum albumin (p<0.001), hemoglobin (p=0.005), calcium (p=0.041) and estimated glomerular filtration rate (eGFR) (p=0.041), but significantly higher 24-hour proteinuria (p=0.011) and more females (p=0.006). Vitamin D was negatively correlated with Alx@75 augmentation pressure, parathyroid hormone, proteinuria and body mass index, and positively correlated with albumin, hemoglobin, eGFR, calcium and transferrin. 25(OH)D was independently associated with Alx@75 (beta=-0.469, p=0.001) and albumin (beta=0.447, p=0.002). Conclusion: In CKD patients 25(OH)D deficiency was common, particularly in females. Level of 25(OH)D was independently associated with Alx@75.

Summary Acute kidney injury is an important cause of mortality and morbidity today and can occur due to several reasons. As time, geographic regions, and living conditions change, various etiological agents arise with nephrotoxic effects. Awareness of such nephrotoxic effects has been raised with the increasing frequency of addictive substance use, especially among young people in society.

Hypertension (HT) represents a major public health problem affecting many individuals worldwide. It is well known to be an important risk factor for the development of cerebrovascular and cardiovascular diseases. Classifying hypertension as 'primary' or 'secondary' depends on the underlying mechanism. In 5 to 10% of hypertensive patients, HT develops 'secondary' to a separate mechanism that has been encountered with increasing frequency in the tertiary refferral centers. The frequent causes of secondary hypertension include renal parenchymal disease, renal artery stenosis, primary hyperaldosteronism, phaeochromocytoma and Cushing's syndrome. Polyarteritis nodosa (PAN) can involve any organ and in varying degrees. Here we present a young hypertensive patient diagnosed as PAN with the angiographic findings of multiple microaneurysms involving celiac, renal and superior mesenteric arteries and associated with a rarely seen neurological entity-PRES syndrome.

La hipertensión es uno de los principales problemas de salud pública, que afecta a muchas personas en todo el mundo. Se sabe que es un importante factor de riesgo para el desarrollo de enfermedades cerebrovasculares y cardiovasculares. Su clasificación como "primaria" o "secundaria" depende del proceso subyacente. En el 5-10% de los pacientes hipertensos, se trata de un problema "secundario" a otro proceso de creciente frecuencia en los centros de atención terciaria. Las causas más frecuentes de la hipertensión secundaria son: enfermedades del parénquima renal, estenosis de la arteria renal, hiperaldosteronismo primario, feocromocitoma y el síndrome de Cushing. La poliarteritis nodosa puede afectar a cualquier órgano y en diferentes grados. A continuación presentamos a un paciente joven hipertenso al que se le ha diagnosticado poliarteritis nodosa, cuya angiografía muestra múltiples microaneurismas que afectan al tronco celíaco, a la arteria renal y a la arteria mesentérica superior, asociada a un síndrome de encefalopatía posterior reversible de entidad neurológica poco visto.