Clinical outcomes and mortality in elderly peritoneal dialysis patients

OBJECTIVES:

To evaluate the clinical outcomes and identify the predictors of mortality in elderly patients undergoing peritoneal dialysis.

METHODS:

We conducted a retrospective study including all incident peritoneal dialysis cases in patients ≥65 years of age treated from 2001 to 2014. Demographic and clinical data on the initiation of peritoneal dialysis and the clinical events during the study period were collected. Infectious complications were recorded. Overall and technique survival rates were analyzed.

RESULTS:

Fifty-eight patients who began peritoneal dialysis during the study period were considered for analysis, and 50 of these patients were included in the final analysis. Peritoneal dialysis exchanges were performed by another person for 65% of the patients, whereas 79.9% of patients preferred to perform the peritoneal dialysis themselves. Peritonitis and catheter exit site/tunnel infection incidences were 20.4±16.3 and 24.6±17.4 patient-months, respectively. During the follow-up period, 40 patients were withdrawn from peritoneal dialysis. Causes of death included peritonitis and/or sepsis (50%) and cardiovascular events (30%). The mean patient survival time was 38.9±4.3 months, and the survival rates were 78.8%, 66.8%, 50.9% and 19.5% at 1, 2, 3 and 4 years after peritoneal dialysis initiation, respectively. Advanced age, the presence of additional diseases, increased episodes of peritonitis, the use of continuous ambulatory peritoneal dialysis, and low albumin levels and daily urine volumes (<100 ml) at the initiation of peritoneal dialysis were predictors of mortality. The mean technique survival duration was 61.7±5.2 months. The technique survival rates were 97.9%, 90.6%, 81.5% and 71% at 1, 2, 3 and 4 years, respectively. None of the factors analyzed were predictors of technique survival.

CONCLUSIONS:

Mortality was higher in elderly patients. Factors affecting mortality in elderly patients included advanced age, the presence of comorbid diseases, increased episodes of peritonitis, use of continuous ambulatory peritoneal dialysis, and low albumin levels and daily urine volumes (<100 ml) at the initiation of peritoneal dialysis.     

Are radio‐contrast agents commonly used in discography toxic to the intact intervertebral disc tissue cells?

In the literature, there have been no studies showing clear results on how radio‐contrast pharmaceuticals would affect intact disc tissue cells. In this context, it was aimed to evaluate the effects of iopromide and gadoxetic acid, frequently used in the discography, on intact lumbar disc tissue in pharmaco‐molecular and histopathological level. Primary cell cultures were prepared from the healthy disc tissue of the patients operated in the neurosurgery clinic. Except for the control group, the cultures were incubated with the indicated radio‐contrast agents. Cell viability, toxicity and proliferation indices were tested at specific time intervals. The cell viability was quantitatively analysed. It was also visually rechecked under a fluorescence microscope with acridine orange/propidium iodide staining. Simultaneously, cell surface morphology was analysed with an inverted light microscope, while haematoxylin and eosin (H&E) staining methodology was used in the histopathological evaluations. The obtained data were evaluated statistically. Unlike the literature, iopromide or gadoxetic acid did not have any adverse effects on the cell viability, proliferation and toxicity (P < 0.05). Although this study reveals that radio‐contrast pharmaceuticals used in the discography, often used in neurosurgical practice, can be safely used, it should be remembered that this study was performed in an in vitro environment.     

Renal sarcoidosis with normal serum vitamin D and refractory hypercalcemia

Introduction

Sarcoidosis is a multi-system disorder characterized by non-caseating epithelioid granulomas in multiple organs. Renal involvement may usually occur as granulomatous interstitial nephritis, but renal failure is uncommon. We report a case of renal-limited sarcoidosis diagnosed by renal biopsy, associated with abnormal calcium metabolism.

Case presentation

A 30-year-old Caucasian male presented with unexplained renal function impairment and hypercalcemia. The patient did not have any history of kidney disease, cough, skin rash, dysuria, hematuria or any other symptoms. Physical examination was unremarkable. Serum creatinine was 2.2 mg/dl and serum calcium was 11.5 mg/dl. Serum intact parathyroid hormone level (12 pg/mL) was decreased. Serum angiotensin-converting enzyme (ACE), 1,25-dihydroxyvitamin D (1,alpha-25 vit D) and pre-proparathyroid hormone (PTHrP) levels and urinary calcium excretion were all in normal range. The renal biopsy showed severe interstitial nephritis with non-caseating granuloma. The patient was treated with prednisone with starting dose of 1 mg/kg. After 2 months of prednisone therapy, serum creatinine decreased. However, because of continued of hypercalcemia unresponsive to low calcium diet and prednisone, chloroquine was prescribed. Six months after the onset, the patient's serum creatinine is stable at 1.30 mg/dl, serum calcium is 10.8 mg/dl, and serum ACE and 1,alpha-25 vit D levels are in normal range. He does not have any signs of extra-renal relapse.

Conclusion

The mechanisms of abnormal calcium metabolism in this patient with renal-limited sarcoidosis are unclear.     

The Effect of K-ATP Channel Blockage During Erythropoietin Treatment in Renal Ischemia-Reperfusion Injury

ATP dependent K channels (K-ATP) take part in the Erythropoietin (EPO) induced cardioprotection but these channel activations have role in cytoprotective role of EPO in the renal ischemia reperfusion (IR) damage is still unknown. For this purpose rats were pretreated with EPO (500 IU/kg) and/or K-ATP channel blocker glibenclamide (40mM/kg) i.p. before bilateral renal IR damage. Renal tissues were used for histological examination and measurement of caspase-3 and TNF-α levels. Renal functions were evaluated by glomerular filtration rate (GFR) fractional excretion of sodium (FENa) and potassium (FEK). Renal TNF-α and caspase-3 levels were decreased in both glibenclamide and EPO-treated IR rats compared to untreated rats. The protection afforded by the pretreatment with EPO alone was greater than that of administering glibenclamide alone. Application of glibenclamide at the same time partly abolished the cytoprotective effect of EPO treatment. K-ATP mediated cytoprotection is not the main mechanism of protective effect of EPO.     

Genetic Testing in Head and Neck Paraganglioma: Who,What, and Why?

Background Genetic testing in head and neck paragangliomas (HNPG) can have profound implications in patient and family counseling.Methods Retrospective review was performed of patients with HNPG at a cancer care center from 1970 to present. Patient demographics, disease patterns, outcomes, and genetic mutations were analyzed.Results We identified 26 patients with available genetic testing results. Sixteen had mutations. Succinate dehydrogenase gene, sub unit D (SDHD) accounted for 75% of mutations, of which P81L accounted for 75%. The remainder had SDHB mutations. Patients with mutations were younger (average age 39.5 years versus 48.4 years), 63% (versus 40%) had multiple tumors, 94% (60%) had at least one carotid body tumor, and family history was positive in 38% (20%).Conclusion Patients suspected of heritable HNPG should undergo testing first at the SDHD and SDHB loci, and those with younger age, multiple tumors, carotid body tumors, and positive family history are more likely to have mutations.     

Acute emergency tibialization of the fibula: reconstruction of a massive tibial defect in a type IIIC open fracture

Gustilo type IIIC open fractures of the tibia are high-energy injuries necessitating long treatment periods and usually multiple surgical procedures and eventually resulting in high morbidity rates and even amputations. We present here a case involving a type IIIC open tibial fracture with massive loss of the entire tibial diaphysis, which we treated by performing acute tibialization of the fibula after revascularization of the posterior tibial artery in a single-stage emergency operation.     

In vitro release and In vivo biocompatibility studies of biomimetic multilayered alginate-chitosan/β-TCP scaffold for osteochondral tissue

Biomimetic three-layered monolithic scaffold (TLS) intended for the treatment of osteocondral defects was prepared by using alginate, chitosan and β-tricalcium phosphate (β-TCP) to study drug release behavior of the alternative drug delivery system and to investigate the therapeutic efficacy of the scaffold. Dexamethasone sodium phosphate (Dex) as a model drug was incorporated into the scaffold by solvent sorption method and in vitro release studies were conducted. In addition, the scaffold was implanted into the defects formed in the trochlea of Sprague–Dawley rats to assess the healing potential of the TLS on the osteochondral defect against reference Maioregen® comparatively. The release studies showed that after an initial burst at 3rd h, dexamethasone is released slowly during a 72-h period. In vivo studies indicated that the TLS has good tissue biocompatibility and biodegradation rate and showed better results during osteochondral healing process compared to the reference. All results demonstrated that the alginate-chitosan/β-TCP scaffold could be evaluated as a good candidate for osteochondral tissue applications.     

The Effect of Regional Variations of the Trabecular Bone Properties on the Compressive Strength of Human Vertebral Bodies

Cancellous centrum is a major component of the vertebral body and significantly contributes to its structural strength and fracture risk. We hypothesized that the variability of cancellous bone properties in the centrum is associated with vertebral strength. Microcomputed tomography (micro-CT)-based gray level density (GLD), bone volume fraction (BV/TV), and finite element modulus (E) were examined for different regions of the trabecular centrum and correlated with vertebral body strength determined experimentally. Two sets of images in the cancellous centrum were digitally prepared from micro-CT images of eight human vertebral bodies (T10–L5). One set included a cubic volume (1 per vertebral centrum, n = 8) in which the largest amount of cancellous material from the centrum was included but all the shell materials were excluded. The other set included cylindrical volumes (6 per vertebral centrum, n = 48) from the anterior (4 regions: front, center, left, and right of the midline of vertebra) and the posterior (2 regions: left and right) regions of the centrum. Significant positive correlations of vertebral strength with GLD (r ² = 0.57, p = 0.03) and E (r ² = 0.63, p = 0.02) of the whole centrum and with GLD (r ² = 0.65, p = 0.02), BV/TV (r ² = 0.72, p = 0.01) and E (r ² = 0.85, p = 0.001) of the central region of the vertebral centrum were found. Vertebral strength decreased with increasing coefficient of variation of GLD, BV/TV, and E calculated from subregions of the vertebral centrum. The values of GLD, BV/TV, and E in centrum were significantly smaller for the anterior region than for the posterior region. Overall, these findings supported the significant role of regional variability of centrum properties in determining the whole vertebral strength.     

Effect of LED curing modes on the microleakage of a pit and fissure sealant

PURPOSE: To evaluate in vitro the curing effect of a very high intensity light-emitting diode (LED) unit and a conventional LED unit (including "soft-start" modes) on the microleakage of a pit and fissure sealant. METHODS: 120 intact caries-free human molars were randomly divided into six groups (n=20), sealed with Fissurit-F and polymerized using either a conventional halogen unit (Optilux) (Control group) in standard mode (40 seconds @ 600 mW/cm2); a very high intensity LED unit (Mini LED) in fast (10 seconds @ 1,100 mW/cm2) or soft-start mode (pulse mode: ten 1-second flashes @ 1,100 mW/cm2; exponential mode: exponential increase from 0 to 1,100 mW/cm2 within 10 seconds followed by 10 seconds @1,100 mW/cm2); or a conventional LED unit (Elipar Freelight) in standard (40 seconds @ 400 mW/cm2) or exponential mode (exponential increase from 0 to 400mW/cm2 within 12 seconds followed by 28 seconds @ 400 mW/cm2). Restored specimens were stored in distilled water at 37 degrees C for 24 hours. Specimens were then immersed in a 0.5% fuchsin dye solution for 24 hours, with half of the specimens from each group subjected to thermocycling (5/55 degrees C; x 1000) prior to dye immersion. After removal from the dye solution, specimens were sectioned and the degree of dye penetration scored. Data was statistically analyzed using the Kruskal-Wallis H test and the Mann-Whitney U-test (P< 0.05). RESULTS: There was no statistically significant difference in microleakage of pit and fissure sealant polymerized using various curing techniques. Thermocycling regimens had no effect on either LED- or halogen-cured specimens.