Epigenetic differences in the innate response after immune stimulation during zebrafish sex differentiation

Infections are able to trigger epigenetic modifications; however, epigenetic-mediating infections in the immune system in fish is currently unavailable. Within this purpose, zebrafish were immune-stimulated with three lipopolysaccharides (LPS) during sex differentiation. Methylation patterns of three immune genes were studied by a candidate gene approach together with gene expression analysis, and in adulthood, sex ratios were determined. It was shown that the entrance of LPS was through the gills and accumulated in the pronephros. Significant hypomethylation levels of CASP9 and a significant CpG site for IL1β after Pseudomonas aeruginosa LPS exposure were found. No methylation difference was observed for TNFα. Gene expression and correlation data differed among studied genes. Sex ratios showed a feminization in dose and LPS strain-dependent manner. Here, it is provided epigenetic regulatory mechanisms derived by innate response and the first evidence of possible epigenetic interactions between the immune and reproductive systems.

Abstract P3-13-07: Is radiofrequency ablation better than lumpectomy for margin status in breast cancer? Results of a randomized clinical trial

PURPOSE: To study the safety and efficacy of ultrasound-guided percutaneous radiofrequency ablation (RFA) as local treatment for breast cancer and to intraoperatively evaluate the margin status after RFA in comparison with lumpectomy.

MATERIAL and METHODS: Preliminary in vitro RF ablation experimentation with two mastectomy specimens was performed to test the electrode, practice the ultrasound technique and evaluate the macroscopic and microscopic effects of RF. Then, aprospective, randomized open-label phase II clinical trial (NCT02281812) was conducted in a single institution from 2013-2017. Forty subjects, mean age 64 (range 46-86), with ductal infiltrating carcinoma of the breast ≤2 cm were randomly assigned to RFA plus lumpectomy or lumpectomy alone. Margin status, tumor cell viability (TCV) after RFA (by nicotinamide adenine dinucleotide (NADH) and Cytokeratin 18 (CK18) staining), adverse events and local recurrences were evaluated by univariable and multivariable analyses (SPSS statistical software).

RESULTS: In the experimental design with mastectomies, the only procedural complication was a skin burn at the entrance site of the electrodes. We learned that the tip of the electrodes should cut cross the tumor by at least 10mm.

The clinical trial includes two groups: study group (n=20) and control group (n=20). NADH and CK18 staining demonstrated absence of TCV after RFA with at least one of the two techniques. The percentage of intraoperatively affected surgical margins was higher in the control group although local adverse effects after surgery was higher in the RFA treatment arm. Three study subjects presented local infection (two had partial irradiation of the breast) and none in the control group. Median follow up was 25 months (range 1–83). No recurrence or second surgery was required during the study period.

Outcomes RFA group (n = 20)Control group (n=20)p valueSpecimen weight (median, gr)42 (24-80)27 (11-60)0.004Specimen volume (median, ml)369 (259-847)201 (100-602)0.004Positive margin (intraoperative)4/20 (20%)11/20 (55%)0.022Pathological size (median, mm)11.5 (5-20)10.5 (6-16)0.07Local Adverse effect8/20 (40%)1/20 (5%)0.01Breast Inflammation5/20 (25%)1/20 (5%)0.182Breast Infection3/20 (15%)0/20 (0%)0.23RFA: radiofrequency ablation. n=number of subjects

CONCLUSION: RFA seems effective in the cases considered and could be more accurate than lumpectomy in terms of obtaining more free margins. Surgical excision associated with RFA leads to a higher amount of local adverse effects, especially if combined with partial irradiation of the breast. RFA could be considered as a less invasive treatment in tumors smaller than 20 mm; however, this warrants further investigation.

Citation Format: Garcia-Tejedor A, Guma A, Soler T, Valdivieso A, Petit A, Contreras N, Chappuis CG, Falo C, Pernas S, Anselem A, Fernandez-Montoli E, Pla MJ, Burdio F, Ponce J. Is radiofrequency ablation better than lumpectomy for margin status in breast cancer? Results of a randomized clinical trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-13-07.

Intraoperative Portal Flow of Less Than 1 Liter per Minute After Orthotopic Liver Transplantation Is Not Associated Per Se With an Increased Rate of Early Graft Dysfunction

OBJECTIVE

The aim of this study was to determine whether a portal flow of <1,000 mL/min in orthotopic liver transplantation (OLT) is associated with a higher incidence of early graft dysfunction (EGD) and graft loss.

METHODS

A retrospective study was performed of 540 OLTs carried out consecutively from December 2004 to December 2013. Patients were divided into 2 groups: group A, portal flow <1,000 mL/min; and group B, portal flow >1,000 mL/min. We studied the incidence of EGD and graft survival. A subanalysis was performed to define the minimum acceptable portal flow/100 g of liver weight to reduce the development EGD and graft loss.

RESULTS

Group A included 29 patients and group B, 511 patients. Group A had significantly lower-weight donors and recipients, female recipients with cholestatic disease, lower MELD scores, and lower hepatic artery flow. EGD occurred in 7 patients in group A (24.1%) versus 101 patients in group B (19.8%; P = .43). No significant differences were found in 1- and 5-year graft survival. A portal flow of <80 mL/min/100 g of liver weight was related to a significantly higher risk of developing EGD (odds ratio, 4.35; 95% confidence interval [CI], 1.46-12.91; P = .008) and graft loss (hazard ratio, 4.05; 95% CI, 1.32-12.42; P = .014).

CONCLUSIONS

Intraoperative portal flow of <1,000 mL/min in OLT was not related per se with a higher incidence of EGD or graft loss. Significantly higher risk of developing EGD and graft loss was associated with a portal flow of <80 mL/min/100 g of liver weight.

Risk factors for biliary complications after orthotopic liver transplantation with T-tube: a single-center cohort of 743 transplants

BACKGROUND

Despite recent advances in organ preservation, surgical procedures, and immunosuppression, biliary reconstruction after orthotopic liver transplantation (OLT) remains as a major source of morbidity. The purpose of this study was to identify risk factors for the development of biliary complications (BCs) after end-to-end choledochocholedochostomy (EE-CC) with a T-tube as the standard technique for biliary reconstruction after OLT.

METHODS

A total of 833 consecutive liver transplantations that took place from February 1996 to April 2010 were retrospectively reviewed. Patients with concomitant hepatic artery complications were excluded, as were those who underwent urgent retransplantation or died within 1 week after transplantation. Finally, the study group comprised 743 patients.

RESULTS

The overall BC rate was 9.8% (73 patients), including stricture in 19 patients (2.6%) and bile leakage in 39 patients (5.2%). After univariate analysis, significant risk factors for BCs were surgery time >5 hours, arterial ischemia time >30 minutes, use of a classic transplant technique, transfusion of red blood cells ≥5 units, anti-cytomegalovirus treatment, and period of transplantation between 1996 and 2002. Stepwise logistic regression study was performed, including those variables with a value of P <.200. Multivariate analysis showed that pretransplant serum creatinine (odds ratio = 1.27; 95% confidence interval [CI], 1.03-1.57; P = .025) and arterial ischemia time >30 minutes (odds ratio = 2.44; 95% CI, 1.45-4.12; P = .001) were the only independent risk factors related to the development of BCs after biliary reconstruction with the T-tube.

CONCLUSIONS

The performance of different variables in predicting occurrence of BCs was assessed with the use of receiver operating characteristic analysis. The area under the receiver operating characteristic curve of our model was 0.637 (95% CI, 0.564-0.710), and therefore we must conclude that other variables not included in our model may have influence in the development of BCs after OLT with an EE-CC with a T-tube as the procedure for biliary reconstruction.

Biliary complications in orthotopic liver transplantation using choledochocholedochostomy with a T-tube

Despite significant advances in orthotopic liver transplantation (OLT), biliary tract reconstruction is still a major source of complications. Choledochocholedochostomy with a T-tube used to be the standard procedure for biliary reconstruction after OLT. However, many centers currently avoid use of the T-tube because of the high incidence of complications. Our aim was to study the biliary complications occurring at our center when end-to-end choledochocholedochostomy (EE-CC) over a T-tube was used as the standard procedure for biliary reconstruction. A retrospective review was conducted of all patients who underwent liver transplantation from February 1, 1996, to April 30, 2010. Only patients requiring any therapy to treat biliary complications were considered, whereas those with concomitant hepatic artery complications were excluded. The study cohort consisted of 743 patients who had EE-CC with a T-tube. Of these, 73 patients (9.8%) experienced any biliary complication. Anastomotic strictures occurred in 17 patients (2.3%), and non-anastomotic strictures in 2 (0.3%). Fifteen patients with anastomotic strictures were successfully treated by dilatation and stenting. Bile leakage was diagnosed in 39 patients (5.2%). Leakage occurred at the anastomosis in 15 patients (2%), and at the exit site of the T-tube in 24 patients (3.2%). Tube opening was the only treatment used in 30 patients with bile leakage (76.9%). Seven patients experienced leaks after elective T-tube removal (1%). Overall, repeat surgery to manage biliary complications was needed in 9 patients (1.2%). The mortality rate from biliary complications was 0.13%. In conclusion, EE-CC with a T-tube was followed by a low incidence of biliary complications. The complication rate after elective T-tube removal and the repeat surgery rate were extremely low. These results might challenge the current trend to avoid T-tube stenting in OLT.

Incidence and clinical relevance of bacterial contamination in preservation solution for liver transplantation

OBJECTIVE

Postoperative infection is considered one of the most important causes of morbidity and mortality after liver transplantation. We prospectively studied the incidence and significance of infections in preservation solutions for liver transplantation.

MATERIALS AND METHODS

From March 2007 to March 2008, we cultured the University of Wisconsin preservation solution for 60 consecutive liver transplantations. Fluid samples were obtained at the beginning and at the end of the back table procedure. Our posttransplant infection prophylactic protocol consisted of ampicillin and cefotaxime for 48 hours.

RESULTS

Cultures were positive in 59 patients (98.4%). Seventy-five percent of the isolates were superficial saprophytic flora (SSF; Staphylococcus coagulase negative, Streptococcus viridans, and Corynebacterium), nevertheless in 15 cases (25.1%) we isolated high virulence pathogens (Staphylococcus aureus, Klebsiella, Escherichia coli, Enterobacter, and Pseudomonas aeruginosa). There were neither anaerobic nor fungal isolates. Sixteen patients (36%) from the group with SSF developed postoperative fever, including 12 with negative posttransplant cultures, while 4 patients showed positive cultures for various microorganisms distinct from those isolated from the preservation solution. Five patients (30%) with high virulence pathogens in the preservation solution developed posttransplant fever, although no pathogen was isolated.

CONCLUSIONS

Positive cultures of preservation fluids were observed in 98% of patients, although most of them (75%) were SSF. Microorganisms isolated from posttransplant cultures did not match the ones obtained from the preservation solution. Our results did not support routine culturing of the preservation solution provided that one administrator an adequate posttransplant antibiotic prophylactic regimen.

Prophylactic therapy with valgancyclovir in high-risk (cytomegalovirus D+/R-) liver transplant recipients: a single-center experience

A retrospective study was performed in liver transplant patients with high risk to develop cytomegalovirus infection (CMV D+/R-) who were treated with valgancyclovir for 3 months as prophylactic therapy. The aim of this study was to determine the safety and efficacy of prophylactic therapy with valgancyclovir. Weekly CMV antigenemia was routinely assessed during the first 3 months posttransplantation, twice a month to month 6, and monthly until the end of the first year, as well as when clinically indicated. The follow-up period was 1 year. From January 2003 to February 2007, 199 liver transplantations were performed at our institution, including 23 (11%) high-risk patients for CMV infection. Median age was 47 +/- 11.6 years. Nineteen patients (70.4%) were men. Five subjects (21.7%) developed CMV infections. Three patients with positive CMV antigenemia at 3, 4, or 6 months posttransplantation were asymptomatic, while 2 (8.7%) showed gastrointestinal CMV disease at 2 months posttransplantation or CMV hepatitis at 1 month after the end of the prophylactic therapy. Treatment with intravenous gancyclovir followed by oral valgancyclovir was successful in both patients. No opportunistic infections were observed and only 1 patient developed leukopenia as an adverse event related to valgancyclovir.

Effects of annual influenza vaccination on winter mortality in elderly people with chronic pulmonary disease

BACKGROUND

Although there is a general agreement for the recommendation of the influenza vaccine to persons with chronic obstructive pulmonary disease (COPD), the magnitude of clinical effectiveness and benefit from the annual vaccination is controversial. We assessed the effects of annual influenza vaccination on winter mortality in older adults with COPD.

METHODS

This prospective cohort study included 1298 Spanish community-dwelling individuals aged 65 years or older with a diagnosis of COPD followed from 1 January 2002 to 30 April 2005. The primary outcome was all-cause death during influenza periods (January-April). Multivariable Cox proportional hazard models adjusted by age, sex and comorbidity were used to evaluate vaccine effectiveness.

RESULTS

Influenza vaccination was associated with a non-statistically significant 16% reduction in winter mortality among vaccinated COPD patients [unadjusted hazard ratio (HR): 0.84; 95% confidence interval (CI): 0.60-1.17]. Multivariable analysis showed that there was an insignificant trend towards a reduced mortality in the vaccinated group considering overall influenza periods 2002-2005 (adjusted HR: 0.76; 95% CI: 0.52-1.06; p=0.098). We estimated that, in the total COPD population, one death was prevented for every 187 annual vaccinations (95% CI: 62 to infinity).

CONCLUSIONS

Our data suggest benefit from the influenza vaccination and support an annual vaccination strategy for elderly COPD patients.

Propiedades psicométricas de un cuestionario específico de calidad de vida en trasplante hepático

OBJECTIVE

To translate and evaluate the psychometric properties of a quality of life questionnaire specific to liver transplant patients.

MATERIAL AND METHODS

The questionnaire was administered to 60 patients on the waiting list for liver transplant in the Cruces Hospital Transplant Unit, and again at 6 months after the transplant. The reliability, validity, sensitivity to change, and minimum detectable change (MDC) were studied. Two questionnaires, the SF-36 (Health Survey Short Form 36) and HADS (Hospital Anxiety and Depression Scale), were used to evaluate the convergent validity.

RESULTS

The specific questionnaire presented a Cronbach s alpha coefficient of over 0.7. The factor analysis demonstrates a single dimension. Correlations with the areas of SF-36 varied between -0.34 and -0.71 in the preoperative phase, and between -0.21 and -0.67 at 6 months. With respect to the HAD-anxiety scale, the coefficients were 0.44 in the preoperative phase and 0.51 at 6 months, and for the HAD-depression scale these were 0.64 and 0.39, respectively. Discriminant validation studies confirm that the questionnaire shows differences between patients with cirrhosis of various etiologies and severities. In the study of sensitivity to change, values were obtained for the SES (standardised effect size) and SRM (standardised response mean) indices of 0.92 and 0.99, respectively. Furthermore, 58.33% of patients had scores higher than MDC.

CONCLUSIONS

The specific questionnaire has adequate psychometric properties. Its use in these patients may therefore be recommended as another scale for evaluating the results of this intervention.

Donors older than 70 years in liver transplantation

INTRODUCTION

Expansion of donor criteria has become necessary with the increasing number of liver transplantation candidates, as aged donors who have been considered to yield marginal organs.

METHODS

Our database of 477 liver transplants (OLT) included 55 cases performed from donors at least 70 years old vs 422 with younger donors. We analyzed pretransplantation donor and recipient characteristics as well as evolution of the recipients.

RESULTS

The old donor group showed significantly lower ALT (23 +/- 17 vs 48.9 +/- 67; P = .0001) and LDH (444 +/- 285 vs 570 +/- 329; P = .01). There was a trend toward fewer hypotensive events in the aged donor group (27.2% vs 40.5%; P = .07). No steatosis (>10%) was accepted in the old donor group. Cold ischemia time was statistically shorter for the aged donors (297 +/- 90 minutes vs 346 +/- 139 minutes; P = .03). With these selected donors, the results were not different for primary nonfunction, arterial and biliary complications, hospitalization, acute reoperation or acute retransplantation, and hospital mortality when donors > or =70 years old were compared to younger donors. Functional cholestasis, neither related to rejection nor to biliary complications, was seen more frequently in old donor recipients (40% vs 22%; P = .03). No differences in 1, and 3 year survivals were observed between recipients of donors over 70 years old and these of younger organs: 93.8% and 90.6% vs 90.7% and 82.8%, respectively.

CONCLUSION

When using selected donors > or =70 years old the outcomes were comparable to those obtained with younger donors. Strict selection is necessary to achieve good long-term survival.

Implante coclear en malformaciones congénitas

OBJECTIVE

The main objective is to evaluate the complications and problems encountered in a population with inner ear congenital malformation undergoing cochlear implantation.

MATERIALS AND METHODS

The present study includes 33 patients with congenital inner ear malformation, from a total population of 346 cochlear implant patients, implanted from February 1993 to March 2004. Radiological evaluation and neurological exams were performed to all these patients in order to evaluate all the preoperative conditions.

RESULTS

The most common cochlear anomalies we found were: cochlear hypoplasia, Incomplete partition and Common cavity (n=15). In 4 cases an enlarge aqueduct was also associated to the cochlear anomaly. We also found 6 cases with labyrinthine anomalies. The surgical procedure was performed in 23 cases, and in 18 of them we obtained an electrical stimulation of the neural elements.

CONCLUSIONS

There are no differences between patients with Incomplete Partition of the cochlea and mild Cochlea hypoplasia, if compared with those with normal cochlea. Severe malformations as Common Cavity or severe hypoplasia may have a higher rate of surgical complications and the outcome cannot be predicted.

Liver transplantation for hepatocellular carcinoma in cirrhotic patients

A consecutive series of 88 patients underwent transplantation for hepatocellular carcinoma with cirrhosis over a 7-year period. Liver transplantation was indicated because of the tumor in 75 cases (85.2%); tumor was an incidental finding in 13 cases (14.8%). One patient was retransplanted due to primary nonfunction. The perioperative mortality was 4.5%. Tumor recurrence was observed in seven patients (7.95%) with incidental tumor recurrence in one case. As in patients with known primary liver tumors pretransplant, a thorough follow-up is advisable to establish an early diagnosis of recurrence. The actuarial survival for nonincidental hepatocellular carcinoma at 1, 3, and 5 year was 92%, 77%, and 75%, respectively. The differences in actuarial survival between hepatitis C negative and positive hepatocellular carcinoma were not significant (log-rank test P=.27), though there was a clear improvement in results (94%, 85%, and 78% vs 90%, 71%, and 71%), at 1, 3, and 5 years meaning that HCV infection is an important prognostic factor. Although transplantation for HCC has the advantages of removing the tumor and the cirrhotic liver, it remains a controversial topic. In our experience patients showing lesions less than 5 cm or three or fewer lesions experience an equivalent survival to transplanted patients who do not have cancer.

Liver transplantation for peripheral cholangiocarcinoma: Spanish experience

INTRODUCTION

Palliative treatment for nondisseminated unresectable peripheral cholangiocarcinoma (PCC) carries a 0% 5-year survival rate. The role of orthotopic liver transplantation (OLT) in these patients is controversial because the survival rate is lower than with other indications for transplantation and the lack of available donor organs. The aim of this paper was to review the Spanish experience in OLT for PCC to identify prognostic factors for survival.

METHODS

We retrospectively reviewed 23 patients undergoing OLT in Spain for PCC over a period of 13 years.

RESULTS

The actuarial survival rates were 77%, 65%, and 42% at 1, 3, and 5 years, respectively. The main cause of death was tumor recurrence (35%). Prognotic factors for an adverse outcome were pTNM classification (P<.05) in the univariate analysis and perineural invasion (P<.05) and stages III or IVA (P<.05) in the multivariate analysis.

CONCLUSIONS

OLT for nondisseminated irresectable PCC displays higher survival rates at 3 and 5 years than palliative treatments, especially for tumors in the initial stages, which means that more information is needed to help better select PCC patients for transplantation.

Liver transplantation for hilar cholangiocarcinoma: Spanish experience

INTRODUCTION

Palliative treatment for nondisseminated irresectable hilar cholangiocarcinoma (HCC) carries a 0% 5-year survival rate. The role of orthotopic liver transplantation (OLT) in these patients is controversial because the survival rate is lower than that for other indications for transplantation and the lack of available donor organs. The aim of this paper was to review the Spanish experience in OLT for HCC and identify prognostic factors for survival.

METHODS

We retrospectively reviewed 36 patients undergoing OLT for HCC over 13 years.

RESULTS

The actuarial survival rate at 1, 3, and 5 years was 82%, 53%, and 30%, respectively. The main cause of death was tumor recurrence (53%). In the univariate analysis, the factors for a poor prognosis were vascular invasion (P<.001) namely 0% survival at 3 years when present versus 63% and 35% at 3 and 5 years, respectively, when it was not; and stages III to IVA (P<.05), namely 15% survival at 5 years versus 47% for stages I to II. Lymph node and perineural invasion also reduce survival. In the multivariate analysis, the factors for poor prognosis included vascular invasion (P<.01) and stages III to IVA (P<.01).

CONCLUSION

OLT for nondisseminated irresectable HCC has higher survival rates at 3 and 5 years than palliative treatments, especially with initial stage tumors, which means that more information is needed to better select cholangiocarcinoma patients for transplantation.

[Effect of PTH, phosphate, and metabolic acidosis on the progression of renal insufficiency in the azotemic rat]

In a previous study we have observed that NH4Cl-induced metabolic acidosis halted the progression of renal disease in azotemic rats with a high phosphate diet. We hypothesized that NH4Cl-induced metabolic acidosis may exert its protective effect by decreasing renal calcium content independent of serum levels of PTH and phosphate loading. To test this hypothesis we studied azotemic rats with very low phosphate diet or parathyroidectomy. Rats with low phosphate diet and parathyroidectomized rats developed renal failure after 5/6 nephrectomy, and in both groups the acid loading significantly decreased the progression of renal disease. Calcium renal content increased in both groups, even in rats with low phosphate diet, and this effect was also significantly decreased after an acid loading. Rats with acid loading developed greater hypertrophy of renal tissue than rats without acid loading. We conclude that NH4Cl-induced metabolic acidosis halted the progression of renal disease by decreasing calcium precipitation on renal tissue. Parathyroidectomy did not prevent progression of renal disease nor calcium precipitation, and a low phosphate diet in azotemic rats did not prevent increased calcium content on remnant renal tissue.

Effect of calcitriol treatment and withdrawal on hyperparathyroidism in haemodialysis patients with hypocalcaemia

BACKGROUND

Calcitriol is used to treat secondary hyperparathyroidism in dialysis patients. For similarly elevated parathyroid hormone (PTH) levels, the PTH response to calcitriol treatment is believed to be better in hypocalcaemic dialysis patients than in dialysis patients with higher serum calcium values. Furthermore, few studies have evaluated the rapidity of the rebound in serum PTH values after prolonged treatment with calcitriol. Our goal was to evaluate (i) the PTH response to calcitriol treatment in hypocalcaemic haemodialysis patients, (ii) the rapidity of rebound in PTH after calcitriol treatment was stopped, and (iii) whether the effect of calcitriol treatment on PTH levels could be separated from those produced by changes in serum calcium and phosphate values.

METHODS

Eight haemodialysis patients (29+/-3 years) with hypocalcaemia and hyperparathyroidism were treated thrice weekly with 2 microg of intravenous calcitriol and were dialysed with a 3.5 mEq/l calcium dialysate. Parathyroid function (PTH-calcium curve) was determined before and after 30 weeks of calcitriol treatment and 15 weeks after calcitriol treatment was stopped.

RESULTS

Pretreatment PTH and ionized calcium values were 907+/-127 pg/ml and 3.89+/-0.12 mg/dl (normal, 4.52+/-0.07 mg/dl). During calcitriol treatment, one patient did not respond, but basal (predialysis) PTH values in the other seven patients decreased from 846+/-129 to 72+/-12 pg/ml, P<0.001 and in all seven patients, the decrease exceeded 85%. During the 15 weeks after calcitriol treatment was stopped, a slow rebound in basal PTH values in the seven patients was observed, 72+/-12 to 375+/-44 pg/ml. Covariance analysis was used to evaluate the three tests of parathyroid function (0, 30, and 45 weeks), and showed that calcitriol treatment was associated with reductions in maximal PTH values while reductions in basal PTH were affected by ionized calcium and serum phosphate. The basal/maximal PTH ratio and the set point of calcium were associated with changes in ionized calcium.

CONCLUSIONS

In haemodialysis patients with hypocalcaemia, (i) moderate to severe hyperparathyroidism responded well to treatment with calcitriol, (ii) reductions in maximal PTH were calcitriol dependent while reductions in basal PTH were affected by the ionized calcium and serum phosphate concentrations, (iii) changes in the basal/maximal PTH ratio and the set point of calcium were calcium dependent, and (iv) the delayed rebound in basal PTH levels after withdrawal of calcitriol treatment may have been due to the long duration of treatment and the marked PTH suppression during treatment.

Failure of high doses of calcitriol and hypercalcaemia to induce apoptosis in hyperplastic parathyroid glands of azotaemic rats

BACKGROUND

Whether calcitriol administration, which is used to treat secondary hyperparathyroidism in dialysis patients, induces regression of parathyroid-gland hyperplasia remains a subject of interest and debate. If regression of the parathyroid gland were to occur, the presumed mechanism would be apoptosis. However, information on whether high doses of calcitriol can induce apoptosis of parathyroid cells in hyperplastic parathyroid glands is lacking. Consequently, high doses of calcitriol were given to azotaemic rats and the parathyroid glands were evaluated for apoptosis.

METHODS

Rats were either sham-operated (two groups) or underwent a two-stage 5/6 nephrectomy (three groups). For the first 4 weeks, all rats were given a high (1.2%) phosphorus (P) diet to stimulate parathyroid gland growth and then were changed to a normal (0.6%) P diet for 2 weeks. At week 7, three of the five groups were given high doses of calcitriol (500 pmol/100 g body weight) intraperitoneally every 24 h during 72 h before sacrifice. The five groups during week 7 were: (i) normal renal function (NRF)+0.6% P diet; (ii) NRF+0.6% P+calcitriol; (iii) renal failure (RF)+0.6% P; (iv) RF+1.2% P+calcitriol; and (v) RF+0.6% P+calcitriol. Parathyroid glands were removed at sacrifice and the TUNEL stain was performed to detect apoptosis.

RESULTS

At sacrifice, the respective serum calcium values in calcitriol-treated groups (groups 2, 4, and 5) were 15.52+/-0.26, 13.41+/-0.39 and 15.12+/-0.32 mg/dl. In group 3, PTH was 178+/-42 pg/ml, but in calcitriol-treated groups, PTH values were suppressed, 8+/-1 (group 2), 12+/-2 (group 4), and 7+/-1 pg/ml (group 5). Despite, the severe hypercalcaemia and marked PTH suppression in calcitriol-treated groups, the percentage of apoptotic cells in the parathyroid glands was very low (range 0.08+/-0.04 to 0.25+/-0.20%) and not different among the five groups.

CONCLUSIONS

We found no evidence in hyperplastic parathyroid glands that apoptosis could be induced in azotaemic rats by the combination of high doses of calcitriol and severe hypercalcaemia despite the marked reduction in PTH levels that was observed.

Reduced natriuresis after oral sodium load in cholestatic rats: role of compartment volumes and ANP

The purpose of this study was to assess the participation of the atrial natriuretic peptide (ANP)-cGMP system in electrolyte and volume handling of cholestatic rats submitted to an acute oral sodium load. Cholestasis was induced by ligation and section of the common bile duct (n = 51). Control rats were sham operated (n = 56). Three weeks after surgery, 24-hr urinary volume, sodium, potassium, cGMP and creatinine excretion were measured. Three days later, animals received 10 mmol/kg NaCl (1 M) by gavage, and urinary excretion was measured for 6 hr. In parallel groups of rats, plasma volume, electrolytes and ANP concentration, extracellular fluid volume (ECFV), and renal medullary ANP-induced cGMP production were determined in basal conditions or 1 hr after oral sodium overload. As compared with controls, cholestatic rats had a larger ECFV and higher plasma ANP (67.2 +/- 5.2 vs 39.7 +/- 3.5 pg/ml), but lower hematocrit and blood volume, and were hyponatremic. Cholestatic rats showed higher basal excretion of sodium, potassium, and volume than controls, but equal urinary cGMP. After the NaCl overload, cholestatic rats showed a reduced sodium excretion but equal urinary cGMP. One hr after sodium overload, both groups showed hypernatremia, but whereas in control rats ECFV and ANP increased (50.7 +/- 4.1 pg/ml), in cholestatic rats ECFV was unchanged, and plasma volume and ANP were reduced (37.5 +/- 5.8 pg/ml). ANP-induced cGMP production in renal medulla was similar in cholestatic and control nonloaded rats (14.2 +/- 5.2 vs 13.4 +/- 2.6 fmol/min/mg). One hr after the load, medullary cGMP production rose significantly in both groups, without difference between them (20.6 +/- 3.1 vs 22.7 +/- 1. 7 fmol/min/mg). We conclude that the blunted excretion of an acute oral sodium load in cholestatic rats is associated with lower plasma ANP due to differences in body fluid distribution and cannot be explained by renal refractoriness to ANP.

[Severe and recent hyponatremia and hypokalemia associated to the use of hydrochlorothiazide, enalapril and citalopram. Clinical case]

We report a 72 years old hypertensive female, treated with enalapril 10 mg/day and hydrochlorothiazide 25 mg/day during three years. She presented a depressive disorder and cytalopram was prescribed in a dose of 10 mg/day. Two weeks before admission, a serum electrolyte analysis disclosed normal results and the cytalopram dose was increased to 20 mg/day. The patient was admitted with a hyponatremic encephalopathy with a plasma sodium of 100 mEq/L and a plasma potassium of 2.0 mEq/L. Cytalopram, enalapril and hydrochlorothiazide were discontinued, hypertonic NaCl and KCl were administered. The patient had a favorable evolution with a remarkable improvement of her symptoms.

The kidney in chronic liver disease: circulatory abnormalities, renal sodium handling and role of natriuretic peptides

Patients with chronic liver disease (Läennec's cirrhosis) present sodium chloride retention, leading to fluid accumulation within the extracellular space (edema) and specially in the abdomen (ascites). This article reviews the pathogenesis of the hemodynamic abnormalities observed in these patients, particularly the hypothesis of "primary arterial vasodilation", with an increased nitric oxide production by endothelial cells playing a major role in the pathogenesis of vasodilation. Since excessive renal sodium reabsorption precedes ascites formation, two hypotheses are analyzed with respect to the handling of renal sodium in chronic liver disease: the underfilling and overflow theories. Furthermore, the role of natriuretic peptides is reviewed, the increment in atrial natriuretic peptide observed in well compensated cirrhotic patients being considered as a compensatory response to volume expansion, although with renal resistance to this peptide in early stages of the disease. This review ends with an integrated explanation of the circulatory disturbances, renal sodium retention and renal resistance to atrial natriuretic peptide resulting in the sodium and water abnormalities observed in chronic liver disease.

[Distal renal tubular acidosis and nephrolithiasis in 3 cases of primary Sjögren syndrome]

Tubulo interstitial nephritis, the main manifestation of renal involvement in Sjögren syndrome, may lead to a tubular dysfunction that is usually subclinical. We report three women, aged 32, 35 and 35 years old, with a primary Sjögren syndrome and symptomatic type I or distal tubular acidosis. Two patients had nephrolithiasis and one a nephrocalcinosis. Two had a basal hyperchloremic metabolic acidosis. The ammonium chloride acidification test was abnormal in all, demonstrating a distal tubular defect. None had proximal tubular dysfunction. All had an urinary pH over 6.5 and hypocitraturia and none had hypercalciuria. Renal calculi were composed of calcium oxalate and calcium phosphate in two patients and calcium phosphate and ammonium phosphate in the other. All women had positive antinuclear antibodies with mottled pattern, two had anti Ro antibodies and positive rheumatoid factor and one had hypergammaglobulinemia. None had anti La antibodies, crioglobulinemia or monoclonal proteins.

Pharmacokinetics and pharmacodynamics of penbutolol in healthy and cancer subjects: role of altered protein binding

The pharmacokinetic and pharmacodynamic profiles of penbutolol were examined in healthy volunteers and in cancer patients using a pharmacokinetic/pharmacodynamic (pk/pd) model. After receiving a 40 mg single oral dose of penbutolol, the absorption rate constant, apparent volume of distribution and serum clearance of penbutolol were found to be reduced in the cancer group. Changes in the disposition of the conjugate metabolite were also observed in the cancer patients. Penbutolol unbound fraction in serum was statistically decreased (p < 0.005) in the cancer group, according to the increase in the serum levels of alpha 1-acid glycoprotein seen in that group (p < 0.05). The pharmacodynamic effect of penbutolol was measured as the reduction in heart rate (HR); in healthy volunteers, a linear relationship (p < 0.01) between effect and penbutolol serum concentrations (total or unbound) was found. In contrast, in cancer patients, values of HR did not vary statistically in respect to baseline values. These results show that in cancer patients, a change in the pharmacokinetics of penbutolol occurs (associated with changes in drug protein binding), together with an alteration in the pharmacodynamics.

Influence of vitamin C on the absorption and first pass metabolism of propranolol

The effect of ascorbic acid on the availability of propranolol has been examined. After oral administration of propranolol 80 mg with or without ascorbic acid pretreatment (2 g), the plasma concentrations and urinary excretion of propranolol and its metabolites, 4-hydroxy-propranolol and propranolol-conjugated, were determined by HPLC. Compared to controls, vitamin C decreased the maximum concentration of propranolol from 463 to 334 nmol.l-1, and the area under the propranolol concentration-time curve (from 0 to 24 hours) from 3.13 to 1.96 mumol.l-1.h. The time to reach maximum propranolol concentration was increased from 1.9 to 2.7. The total amount of drug recovered in urine has also significantly diminished (from 12.6 to 4.29 mg). No change in elimination rate was observed, indicating that ascorbic acid had affected both the absorption process and the first pass metabolism. The heart-rate decreased less when propranolol was administered with ascorbic acid in comparison to control subjects, although this interaction has little biological importance.

Propranolol absorption in peptic ulcer disease

This study was designed to determine whether gastroduodenal ulcer influences propranolol absorption. Eleven patients with peptic ulcer disease and eight healthy subjects received 80 mg of propranolol orally. Serum propranolol levels were measured with high-performance liquid chromatography. Ulcer patients showed a significant decrease in mean peak concentration of propranolol (90 +/- 12 ng/ml versus 151 +/- 23 ng/ml) (p < 0.025), in the absorption constant (1.43 +/- 0.21 h-1 versus 0.96 +/- 0.12 h-1) (p < 0.05), and in the area under concentration-time curve (802 +/- 129 ng/ml.h versus 492 +/- 73 ng/ml.h) (p < 0.05). No significant difference was seen in drug effect on the heart at 90 min. We conclude that propranolol is absorbed more slowly in ulcer patients than in healthy subjects, but this delay has no clinical effect after a single dose.

Influence of several surgical techniques in peptic ulcer disease on the oral kinetic of a basic drug

The effect of gastric surgery on the absorption of a basic drug propranolol was studied in 11 patients. 80 mg of propranolol were administered orally before and after surgery. Irrespective of the surgical technique, there was only a significant decrease in the absorption constant Ka (1.10 +/- 0.14 vs 0.72 +/- 0.09) (p < 0.05), indicating a delay in the gastrointestinal absorption, which agreed with the delay in the urine excretion in the first six hours after surgery (6.8 +/- 0.8 vs 1.7 +/- 0.4) (p < 0.001). Patients with vagotomy but without gastric resection showed a significant increase in the time of attainment of peak concentration tmax (2.4 +/- 0.2 vs 3.2 +/- 0.3), and decrease in Ka (1.5 +/- 0.12 vs 0.73 +/- 0.17) (p < 0.05), indicating also a delay in the gastrointestinal absorption, that is not seen in patients with partial gastric resection. We conclude that vagotomy with gastric resection does not modify the absorption of propranolol, and vagotomy without resection delays its absorption but does not decrease it.

[Hypomagnesemia associated with hypokalemia, hyponatremia and metabolic alkalosis. Possible complication of gentamycin therapy]

Hypomagnesemia is a serious abnormality with different causes and usually associated to other disorders of electrolyte metabolism. We report a female patient developing hypomagnesemia after administration of gentamycin. This was associated to severe hypokalemia, hyponatremia and metabolic alkalosis. Possible pathogenetic mechanisms and therapeutic measures are discussed.

[Effect of octopamine on arterial pressure and renal function in the normal rat]

Octopamine is a beta hydroxylated phenylethanolamine which accumulates in patients with chronic liver damage. A pathogenic role of octopamine in hemodynamic and systemic alterations of advanced liver failure was investigated in normal awake rats. An infusion of octopamine (220 ug/kg/min) was associated with an increase in mean arterial pressure, urinary volume, urinary Na and K output and their filtration fractions. Glomerular filtration rate and renal plasma flow were not affected. A sudden and marked decrease in mean blood pressure and diuresis was observed after stopping octopamine infusion. Findings during the infusion differ from those observed in the hepatorenal syndrome, although the post infusion period was characterized by hypotension and oliguria. Octopamine behaves as a vasoconstrictor and may interfere with the action of physiologic neurotransmitters.

Renal function and cardiopulmonary bypass: effect of perfusion pressure

Controversy continues as to whether hypotension during cardiopulmonary bypass (CPB) impairs intraoperative and postoperative renal function. Therefore, 21 patients with normal renal function (plasma creatinine less than 1.2 mg/dL, creatinine clearance greater than 70 mL/min), aged 50 to 70 years, without associated pathology, scheduled for elective coronary surgery were studied prospectively. Patients were randomized into two groups: group 1 included 14 patients whose arterial blood pressure during CPB was left untreated, and group 2 consisted of 7 patients who received phenylephrine to maintain their arterial pressure above 70 mmHg. Plasma and urine creatinine, sodium, potassium, and osmolality were measured preoperatively, intraoperatively and postoperatively. Creatinine, osmolal and free water clearances, and excreted sodium fraction were calculated. Plasma creatinine remained normal throughout the study in all patients. Creatinine clearances were similar preoperatively (101.9 +/- 36.7 in group 1 and 120.6 +/- 50.7 mL/min in group 2). In group 1, creatinine clearance decreased during CPB to 88.7 +/- 39.7 mL/min, whereas in group 2 it increased to 157.6 +/- 79.5 mL/min; the difference between groups was significant. Early postoperatively, there was no difference: 136.2 +/- 86.6 mL/min in group 1 and 100 +/- 21.4 mL/min in group 2. One week postoperatively, values were 100.5 +/- 37.9 and 101.9 +/- 18.4, respectively. There was a significant correlation between the creatinine clearance and perfusion pressure intraoperatively, but not postoperatively. Osmolal clearance also correlated with perfusion pressure intraoperatively, but it was significantly lower in the phenylephrine group postoperatively. Postoperative renal function was normal in all patients; no deleterious effect of a low arterial pressure during bypass could be identified.

[Osteomalacia and renal tubular acidosis associated with analgesic abuse. A clinical case]

Osteomalacia is a multifactorial bone disorder. Main causes are vitamin D deficiency and phosphorus depletion. Among patients with renal insufficiency the incidence of osteomalacia is variable and probable related to impairment of the synthesis of 1,25 dihydroxy-vitamin D3 (calcitriol). We report a patients with severe osteomalacia, hyperkalemic tubular acidosis, low serum calcitriol levels and insufficiency associated to a prolonged overuse of analgesic drugs. Differential diagnosis and pathophysiology are discussed.

[Pseudohyponatremia and anion gap changes in multiple myeloma]

Pseudo-hyponatremia is a rare condition characterized by a decrease in plasma sodium concentration associated with a normal or increased effective plasma osmolarity. We present the case of a 62 year old woman with multiple myeloma (IgG) who had a plasma sodium of 84.5 mEq/l (as measured with flame photometry) and an anion gap of -8.8 mEq/l. However, when determined with an ion-selective electrode, plasma sodium was 135 mEq/l. The patient was treated with chemotherapy and did not receive sodium. One week later, plasma sodium--again measured by flame photometry--was 134 mEq/l and the anion gap 4.0 mEq/l. The pathophysiological and clinical aspects of pseudo-hyponatremia and the anion gap are discussed.

[Hepatorenal syndrome]

The clinical and laboratory features of this syndrome are reviewed, with special emphasis upon different mechanisms that may be involved in its pathogenesis.