Endothelial nitric oxide synthase (eNOS) gene polymorphism in early term chronic allograft nephropathy

Chronic allograft nephropathy (CAN) is a complex phenomenon caused by underlying kidney disease with superimposed enviromental and genetic factors. CAN development begins with progressive renal microvascular injury. Endothelial cells play key roles in the regulation of vascular tone, permeability, and remodeling. A reduction in basal nitric oxide (NO) release as a result of genetic variation in endothelial NO synthase (eNOS) function may predispose to hypertension, thrombosis, vasospasm, and atherosclerosis, all contributing to the development of CAN. We analyzed the G894T mutation at exon 7 of the eNOS gene in relationship to CAN among 81 children with renal transplantations. The 20 patients who developed CAN underwent renal biopsies for histological confirmation. Proteinuria and hypertension were observed in CAN. We selected 173 healthy reference subjects. The G894T polymorphism of the eNOS gene was determined by PCR-restriction fragment-length polymorphism analysis. The group included 33 male and 48 female subjects who received 32 living-related grafts and 49 from deceased donors (DD) donors. Donor age (y) was 32.7 +/- 13.7 and the HLA A,B,DR mismatch number of the cadaveric cases was 3.5 +/- 0.79. The distribution of the genotypes were ENOS GG/GT/TT 48%, 33%, 19%, respectively. G-alleles frequency was 64.8%; T-allele frequency was 35.2%. ENOS G894T gene polymorphism did not seem to influence long-term renal allograft outcome. Recipient ENOS G894T gene polymorphism did not alter the risk of chronic allograft failure. Even if NO synthesis and bioactivity are influenced by this polymorphism, many vasoactive factors may have roles to suppress the advantageous effects of NO.

Ellis-Van Creveld syndrome with syndrome X--a rare association from the Indian subcontinent

Ellis-Van Creveld syndrome or chondroectodermal dysplasia is a form of short-limbed dwarfism that affects the skeleton and skin appendages. Disproportionate dwarfism, postaxial polydactyly, ectodermal dysplasia, a small chest, and a high frequency of congenital heart defects characterize this autosomal recessive syndrome. Metabolic consequences of chondroectodermal dysplasia have not been reported previously from India. We report a case of chondroectodermal dysplasia associated with metabolic disturbances qualifying a diagnosis of syndrome X. To our knowledge, this association has not been previously reported in the medical literature, and helps to unravel the metabolic association of this disorder.

Association between Toll-like receptors 4 and 2 gene polymorphisms with chronic allograft nephropathy in Turkish children

Toll-like receptor (TLR) gene polymorphism is known to impair intracellular signaling pathways following adaptive immune responses. Our aim was to investigate the distribution of TLR4 and TLR2 gene polymorphisms among pediatric renal transplantation patients in relation to chronic allograft nephropathy (CAN). In addition to 115 healthy controls, we included 69 renal recipients, 19 of whom were identified as CAN by biopsy scored according to the Banff criteria. Polymorphisms at TLR4 Asp299Gly and/or Thr399Ile were present in 11.6% of renal transplant recipients. None of these subjects was identified in cosegregation with the Thr399Ile allele, whereas three had an isolated Asp299Gly and five had an isolated Thr399Ile. Neither renal recipients nor healthy controls were homozygous for both Asp299Gly and Thr399Ile polymorphisms. However, TLR4 Thr399Ile polymorphism and Ile allele was greater among CAN (-) versus CAN (+) recipients (P > .05). The frequency of TLR2 mutant type Gln allele was significantly higher in recipients than among healthy controls (P < .0001). However, the Gln allele frequency was similar between CAN (+) and CAN (-) patients. The results of present study may be speculated to show TLR4 and TLR2 gene polymorphisms as protective factors from CAN development due to impaired immune responses.

Fitness to fly post craniotomy--a survey of medical advice from long-haul airline carriers

Commercial airline passengers are subject to numerous medical risks while in transit. Seventeen long-haul airline companies were questioned concerning fitness to travel and the case of a patient wishing to travel post craniotomy. Three airline companies gave satisfactory medical information, while the remaining airlines felt it was the decision of the operating surgeon rather than the airline company. A literature review shows that post operative pneumocephalus and the risk of tension pneumocephalus is the major medical concern when transporting patients post craniotomy. Evidence is contradictory with respect to the importance of this potentially life threatening problem. Postoperative 100% oxygen may improve the rate of pneumocephalus absorption. Airline companies have an unstandardised approach to unique medical problems, resulting in increased responsibility for the attending surgeon who may be ill equipped to deal with poorly researched aviation medicine.

Henoch-Schönlein nephritis: a nationwide study

BACKGROUND/AIM

The aim of this retrospective study was to evaluate the presentation, clinical and pathological manifestations and outcome of the Henoch-Schönlein purpura (HSP) nephritis in children.

METHODS

Clinical and laboratory data of 443 children with HSP nephritis aged between 3 and 16 years from 16 pediatric nephrology reference centers were analyzed retrospectively. The biopsy findings were graded according to the classification developed by the International Study of Kidney Disease in Children (ISKDC).

RESULTS

Renal biopsy was performed in 179 of the patients with HSP nephritis. The most common presenting clinical finding in patients who were biopsied was nephrotic range proteinuria (25%) which was followed by nephritic-nephrotic syndrome (23.5%). The biopsy findings according to the ISKDC were as follows: class I: 8.3%; II: 44.1%; III: 36.3%; IV: 6.7%; V: 3.3%; VI: 1.1%. All of the patients who developed end-stage renal disease had nephritic-nephrotic syndrome at presentation. Of 443 patients, 87.2% had a favorable outcome and 12.8% had an unfavorable outcome. The overall percentage of children who developed end-stage renal disease at follow-up was 1.1%. Logistic regression analysis did not show any association of initial symptoms and histology with outcome.

CONCLUSION

In the presented cohort, the presence of crescents in the first biopsy or presenting clinical findings did not seem to predict the outcome of HSP nephritis in children. We conclude that children with HSP nephritis even with isolated microscopic hematuria and/or mild proteinuria should be followed closely.

The role of fcgamma receptor gene polymorphism in pediatric renal transplant rejections

The aim of the study reported herein was to determine whether panel-reactive antibody (PRA) and FcgammaR gene polymorphism act in the same way on acute rejection (AR) and chronic rejection (CR) in children who have undergone renal transplantation. The study evaluated 56 children who underwent transplantation and 115 healthy subjects. AR was observed in 13 cases; CR was observed in 7 patients. The assessment for FcgammaR of the groups in which AR was present showed statistical significance only for the FcgammaIIA genotype. There was no statistical significance for either the FcgammaIIIA or FcgammaIIIB genotypes. Assessment of the FcgammaIIA, IIIA, and IIIB genotypes of the groups in whom CR was present did not show statistical significance. As a result, the prediction of graft survival among transplant recipients is possible using molecular biology. The results of our study showed that individuals of the FcgammaRIIA genotype seemed to have a poorer prognosis similar to some autoimmune diseases. These individuals constitute a risk group for AR. If other studies are conducted with more patients to demonstrate the relationship of other FcgammaRs to rejection, the resultant predictive knowledge about the value of genotypes may lead to improved outcomes following renal transplantation.

Association of TLR2 gene Arg753Gln polymorphism with urinary tract infection in children

The aim of this study is to investigate Arg753Gln allele polymorphisms of toll-like receptor-2 (TLR2) gene distribution, allele frequency in urinary tract infection (UTI) and genotype-phenotype association of TLR2 gene in children with UTI. The polymorphism was investigated in 124 children with UTI (22 boys and 102 girls; mean age 5.81 +/- 3.47 years) with direct DNA sequencing-based method. TLR2 gene Arg753Gln allele frequency was higher in the patient group when compared with control group (OR 3.14, 95%CI 1.53-6.44, P < 0.001). The frequency of the Arg753Gln allele was significantly higher in gram-positive group than in gram-negative group (OR 7.64, 95%CI 2.80-20.81, P < 0.001). The frequency of UTI was found significantly higher in the Arg753Gln allele carriers of TLR2 gene than the non-carriers (OR 4.94, 95%CI 1.09-22.33, P < 0.05). Similarly, the incidence of asymptomatic UTI was also found significantly higher in the group carrying Arg753Gln allele (OR 3.73, 95%Cl 1.54-9.04, P < 0.05). As a result, we suggest that TLR2 gene could be the predisposing factor for urinary tract infection. Additionally, we observed that subjects carrying the TLR2 Arg753Gln allele had higher risk of urinary tract infection with gram-positive pathogens, history of more than two attacks of UTI and asymptomatic UTI.

Worldwide variation of dialysis-associated peritonitis in children

Peritonitis is the most common cause of dialysis failure in children on chronic peritoneal dialysis. We performed a prospective study of 501 peritonitis episodes in 44 pediatric dialysis centers located in 14 countries that examined peritonitis etiology, efficiency of opinion-based management guidelines, and final outcomes. Culture-negative incidence varied significantly from 11% in North America to 67% in Mexico. Argentina and North America had the highest rate of Gram-negative episodes. Pseudomonas-based peritonitis was eightfold more common in the United States than in Europe, and correlated with the frequency of exit site cleansing and topical mupirocin administration. Significant regional variation in antibiotic susceptibility was noted for the first generation cephalosporins and aminoglycosides. Initial response rates to standardized empiric antibiotic treatment did not differ between regions; however, final outcomes were significantly less favorable in Eastern Europe. The wide regional variation in culture-negative peritonitis, and the distribution and antibiotic susceptibilities of causative bacteria needs to be taken into consideration when the guidelines for empiric therapy of pediatric dialysis-associated peritonitis are revised.

A late-onset Epstein-Barr virus-related lymphoma completely remitted in a child with renal allograft

Lymphomas are frequently encountered malignancies following renal transplantations. A 17-year-old boy was found to have lymphoma 1.5 years after a the first cadaveric transplantation performed due to reflux nephropathy. Polyclonal anti-thymocyte globulin (induction) with prednisolone (PRD), azathioprine (AZT), and tacrolimus (Tac) regimen had been given after the transplantation. A hypoechoic mass (25 mm) was detected in the upper pole of the allograft by renal Doppler ultrasound performed due to graft dysfunction with a high basal serum creatinine (Cr) (2.2 mg/dL). The renal biopsy revealed a large B-cell lymphoma with CD20 staining in the medulla. The serum displayed a positive Epstein-Barr virus (EBV), immunoglobulin (Ig)G, negative IgM with negative DNA-polymerase chain reaction. However, the biopsy was positive for EBV-LMA. The viral status at the time of transplant was unknown. After withdrawing AZT and Tac therapies, a chemoimmunotherapeutic regimen consisting of PRD, cyclophosphamide, and anti-CD20 monoclonal antibody was administered twice. The patient excreted the necrosed tumor particles over a 2-month interval with hydronephrotic colic attacks. The basal Cr improved at 6 months (to 1.4 mg/dL). A low dose of Tac (0.5 mg/d) was added to PRD. The patient has remained in complete remission for 2.5 years with a well-functioning renal allograft. Although this case was a late-onset lymphoma, the patient displayed a picture like excreting stones from the allograft and remitted completely. This case illustrates that localization of a tumor may play a more important role than the elapsed time from transplant in the diagnosis in EBV-related posttransplant lymphoproliferative disease.

Revisiting the accuracy of peak flow meters: a double-blind study using formal methods of agreement

BACKGROUND

There is widespread use of peak flow meters in both hospitals and general practice. Previous studies to assess peak flow meter accuracy have shown significant differences in the values obtained from different meters. However, many of these studies did not use human subjects for peak flow measurements and did not compare meters of varying usage. In this study human subjects have been used with meters of varying usage.

METHODS

Participants were tested using two new (meters A and C) and one old peak flow meter (meter B) in random order. The study was double-blinded. Participants were recruited from the university campus.

RESULTS

Four hundred and nine individuals participated. The difference between peak flow means of A and B was -9.93 l/min (95% CI: -12.37 to -7.48, P<0.0001). The difference between peak flow means of B and C was 20.08 l/min (95% CI: 17.85-22.29, P<0.0001). The difference between peak flow means of A and C was 10.15 l/min (95% CI: 7.68-12.61, P<0.0001).

CONCLUSION

There was a significant difference between the values obtained from the new and old peak flow meters and also between the two new peak flow meters. We conclude that there is need for caution in interchangeably using flow meters in clinical practice.

[Relationship between serum testosterone levels and prostatic cancer]

INTRODUCTION

The association between testosterone and prostate cancer badly is understood. The testosterone levels are not conclusive to distinguish benign prostate processes of malignant. The objective of our work is to determine the relation between levels of serum testosterone and prostate cancer.

MATERIAL AND METHOD

38 patients with prostate cancer and a control group of 32 were studied in prospective form, with ages that fluctuated between the 50 and 80 years. The total and free testosterone was determined by radio-immunoensayo. The statistical analysis was descriptive inferential, with bands of 95% confidence.

RESULTS

The average values of total and free testosterone, were significantly smaller in patients with prostate cancer. Any correlation between gleason, prostate antigen and stage with testosterone, was not demonstrated.

CONCLUSIONS

Our work demonstrated that the testosterone is significantly smaller in the patients with prostate cancer that in the controls.

Novel ATP6V1B1 and ATP6V0A4 mutations in autosomal recessive distal renal tubular acidosis with new evidence for hearing loss

Autosomal recessive distal renal tubular acidosis (rdRTA) is characterised by severe hyperchloraemic metabolic acidosis in childhood, hypokalaemia, decreased urinary calcium solubility, and impaired bone physiology and growth. Two types of rdRTA have been differentiated by the presence or absence of sensorineural hearing loss, but appear otherwise clinically similar. Recently, we identified mutations in genes encoding two different subunits of the renal alpha-intercalated cell's apical H(+)-ATPase that cause rdRTA. Defects in the B1 subunit gene ATP6V1B1, and the a4 subunit gene ATP6V0A4, cause rdRTA with deafness and with preserved hearing, respectively. We have investigated 26 new rdRTA kindreds, of which 23 are consanguineous. Linkage analysis of seven novel SNPs and five polymorphic markers in, and tightly linked to, ATP6V1B1 and ATP6V0A4 suggested that four families do not link to either locus, providing strong evidence for additional genetic heterogeneity. In ATP6V1B1, one novel and five previously reported mutations were found in 10 kindreds. In 12 ATP6V0A4 kindreds, seven of 10 mutations were novel. A further nine novel ATP6V0A4 mutations were found in "sporadic" cases. The previously reported association between ATP6V1B1 defects and severe hearing loss in childhood was maintained. However, several patients with ATP6V0A4 mutations have developed hearing loss, usually in young adulthood. We show here that ATP6V0A4 is expressed within the human inner ear. These findings provide further evidence for genetic heterogeneity in rdRTA, extend the spectrum of disease causing mutations in ATP6V1B1 and ATP6V0A4, and show ATP6V0A4 expression within the cochlea for the first time.

Hemodiafiltration for vancomycin overdose in a patient with end-stage renal failure

A 17-year-old anuric female patient with end-stage renal failure received a massive overdose of vancomycin and was treated with high-flux hemodiafiltration, as described in this report. The hemodiafiltration procedure with a polysulfone membrane was performed 3 times. The vancomycin concentration was decreased from 101 mg/l to 16.59 mg/l at the end of the procedure. No adverse effects were noted from either vancomycin or hemodiafiltration. Hemodiafiltration with a high-flux polysulfone membrane is a novel and safe treatment modality for vancomycin overdose in pediatric patients.

Inferior vena cava indices determine volume load in minimal lesion nephrotic syndrome

The pathogenesis of edema in nephrotic syndrome has not been entirely understood. We investigated the value of the echographic parameters [inferior vena cava index (IVCI), inferior vena cava collapsibility index (IVCCI), and left atrium diameter (LAD)] to determine the volume load in children with minimal lesion nephrotic syndrome (MLNS). Twelve children with MLNS (seven boys, five girls) were included in this study. The patients were classified into three different stages (stage A: edematous; stage B: 50% decrease in weight gain; stage C: edema free) following measurement of their ideal weights. The ideal weight of patients in stage A was increased 13 +/- 7%. Serum total protein, albumin and urine sodium levels were found to be low in these patients. Plasma renin activity (PRA) and serum aldosterone levels in stage A were significantly different from those of the control group (P<0.05). PRA and serum aldosterone levels were not different from those of the control group in stage B (P>0.05). However, the increase in PRA was significant in stage C. Although a significant weight decrease was found in stages B and C, it had no effect on IVCI, LAD, and cardiothoracic index. We consider IVCI, IVCCI, and LAD measurements by echocardiography (ECHO) to be easy and reliable clinical methods for assessing the intravascular volume load in patients with MLNS.

Atypical antipsychotics and hyperglycaemia

Hyperglycaemia is known occasionally to occur with conventional neuroleptics, but has more recently been associated with atypical antipsychotics especially clozapine and olanzapine. This article examines more closely this association. A review of relevant published literature from 1970 to date was undertaken following Medline and Embase searches in June 2000. Hyperglycaemia with clozapine was widely reported: spontaneous reports of either hyperglycaemia or ketoacidosis were described in a total of 17 people. In a five-year naturalistic study, 30.5% of patients taking clozapine were eventually diagnosed with Type 2 diabetes. With olanzapine, a total of 10 cases of hyperglycaemia and 5 cases of ketoacidosis have been published. Reports of hyperglycaemia with other atypicals are relatively scarce. The association of hyperglycaemia or ketoacidosis with clozapine and olanzapine appears to be a true drug-induced effect. Risk factors may include male gender, age of around 40 years and being non-Caucasian. The management of hyperglycaemia depends on the causative agent. With clozapine, treatment with oral hypoglycaemics has been successful. With olanzapine, other atypical antipsychotics may be considered. Blood glucose monitoring is essential for all patients starting clozapine or olanzapine.

Potential prophylactic use of benzodiazepines for hemodialysis-associated seizures

Hemodialysis-associated seizure (HAS) is a common complication of hemodialysis. The efficiency of anticonvulsant drugs in treating or preventing seizures is poorly defined. In this study, children on long-term hemodialysis were examined for HAS and the effect of diazepam prophylaxis on HAS was investigated. Nine patients with a mean age of 14.1 + 2.8 years had HAS and 4 with a mean age of 13.0 +/- 4.4 years had never experienced HAS. The patients with HAS had tonic-clonic seizures. Four patients had focal slow-wave paroxysms, especially in the parieto-occipital regions; 2 had subcortical epileptiform discharges by electroencephalography. No correlation was observed between HAS and patient age, primary disease, prior history of seizures, type of dialysis, duration of hemodialysis, anemia, hyperparathyroidism, and administration of erythropoietin. Hypertension due to hypervolemia may also play a role in the development of HAS. Five patients with HAS first treated with phenobarbital (PB) had recurrence of seizures. As a dialyzable antiepileptic PB may be associated with an increased risk for HAS. In a preliminary study, we gave diazepam as a prophylactic therapy to 4 patients with HAS. During 6 months of follow-up, these patients had no seizures. The number of HAS was significantly different between the groups receiving PB and diazepam (z=-2,58, P=0.009). In conclusion, administration of diazepam per os to patients with HAS may be of value for preventing recurrence of HAS.

Does immunologic status predict peritonitis in children treated with CAPD?

The purpose of this study was to evaluate whether immunologic status could predict the development of peritonitis in children on continuous ambulatory peritoneal dialysis (CAPD). Twenty-one patients (12 boys, 9 girls) aged 10.1 +/- 4.32 years (range: 23 months to 14 years) were studied. The mean duration of CAPD treatment was 12.88 +/- 6.69 months (range: 2-22 months). Twelve healthy children (mean age 11.5 years) were selected as a control group. Lymphocyte subpopulations (CD3, CD4, CD8, CD19, NK, and IL-2R) were determined by double-color flow cytometry (Becton-Dickinson). Statistical evaluation was made by Student's t-test. CD4 (38.4 +/- 7.1% vs. 28.0 +/- 5.4%), CD4/CD8 ratio (1.30 +/- 0.4 vs. 0.96 +/- 0.3), and B lymphocyte (19.9 +/- 8.9% vs. 12.0 +/- 3.2%) levels were significantly higher in CAPD patients compared with controls. CAPD patients showed significantly lower natural killer (NK) cell values than controls (12.7 +/- 7.0% vs. 27.3 +/- 8.3%). Apart from CD19 values (21.9 +/- 10.4% vs. 12.0 +/- 3.2%) there were no significant differences between CAPD patients without infection and the control group in the laboratory parameters studied. On the other hand, CD3 (66.3 +/- 7.9% vs. 55.9 +/- 9.7%), CD4 (38.4 +/- 7.1% vs. 28.0 +/- 5.4%), and CD19 (6.3 +/- 3.3% vs. 12.0 +/- 3.2%) levels were significantly higher in CAPD patients with infection compared with the controls. CAPD patients with infection showed significantly lower NK activity (12.7 +/- 7.1% vs. 27.3 +/- 8.3%) than those in the control group. In conclusion, these results can explain the increased vulnerability to peritonitis in CAPD patients compared with healthy subjects. Additionally, immunologic status can predict the development of peritonitis in children treated with CAPD.

Clinicopathologic correlations of Henoch-Schönlein nephritis in Turkish children

BACKGROUND

In this study, 66 patients with Henoch-Schönlein nephritis (HSN) were investigated clinicopathologically.

METHODS

The patients were classified according to their initial presentation, histologic findings, recurrences of purpura, type of treatment and clinical outcome. Logistic regression analysis was performed.

RESULTS

Sixty-eight percent of patients were hospitalized with mild renal disease. Most patients were evaluated as class I and II according to light microscopy. In addition to IgA deposition alone, 33% of patients showed IgA + C3 and 27% had IgA + IgG + C3 depositions. After the follow-up period of 3.3 years, 15 patients had minor urinary findings, 4 had active renal disease and 1 had renal insufficiency. Recurrences occurred in 37.9% of patients and 37.1% of patients with recurrences had persistent pathologic findings. Symptomatic treatment was given to 51.5% of patients, while 27.2% were given corticotherapy.

CONCLUSIONS

Clinical presentation was found to be correlated with outcome. Recurrence of the disease and the type of the treatment also affected the outcome. It was also thought that mesangial IgG and C3 depositions may have a role in the pathogenesis of renal damage in HSN.

Effect of enalapril on proteinuria, phosphaturia, and calciuria in insulin-dependent diabetes

Elevated urinary calcium and phosphate excretion have been observed in children with insulin-dependent diabetes mellitus (IDDM). This may be related to a defect in tubular reabsorption. It is well known that converting enzyme inhibition decreases microalbuminuria and may prevent or retard diabetic nephropathy. We investigated whether enalapril also improves the defect in calcium and phosphate reabsorption. We studied 16 children and young adults (age 12-21 years) with IDDM and persistent microalbuminuria before and during 12 weeks of enalapril treatment. Before treatment microalbuminuria, urinary calcium excretion, and fractional tubular phosphorus reabsorption (TPR) were 153+/-53 microg/min, 5.5+/-0.9 mg/kg per day, and 71.4+/-3.6%, respectively. At the end of the 12th week, microalbuminuria had decreased to 20.3+/-7.9 microg/min and calcium excretion to 3.3+/-0.4 mg/kg per day (P<0.01), while the TPR increased to 80.1+/-3.8% (NS). The renal threshold phosphate concentration increased from 1.8+/-0.15 to 2.92+/-0.23 mg/dl (P<0.01). The fasting serum glucose and hemoglobin Alc levels did not change significantly during the study. Systolic and diastolic blood pressures were 120.4+/-2.2 / 79.3+/-1.4 mm Hg and 110.5+/-1.8 / 71.3+/-0.9 mm Hg before and after 12 weeks, respectively. We conclude that enalapril treatment improves not only microalbuminuria but also abnormal calcium and phosphate excretion in microalbuminuric children with IDDM.

Pindolol augmentation of antidepressant therapy

BACKGROUND

Antidepressant therapy is not always effective and is slow to take effect. In theory, these shortfalls may be caused by induction of neuronal negative feedback via pre-synaptic 5-HTIA receptors. Pindolol, an antagonist at somatodentritic pre-synaptic 5-HTIA receptors has been investigated as a potential accelerator and augmentor of antidepressant response.

METHOD

A Medline search was conducted in November 1997.

RESULTS

Six open-label studies and six controlled studies were identified for review.

CONCLUSIONS

Open-label studies strongly suggest that pindolol may accelerate and augment antidepressant response, but controlled studies do not wholly support these findings: only three of six studies clearly demonstrate benefit. Larger, well-designed, controlled trials are needed to determine definitively the effectiveness of pindolol in this context.