Health care utilization and mortality for people with epilepsy during COVID-19: A population study

OBJECTIVE

This study was undertaken to characterize changes in health care utilization and mortality for people with epilepsy (PWE) during the COVID-19 pandemic.

METHODS

We performed a retrospective study using linked, individual-level, population-scale anonymized health data from the Secure Anonymised Information Linkage databank. We identified PWE living in Wales during the study "pandemic period" (January 1, 2020-June 30, 2021) and during a "prepandemic" period (January 1, 2016-December 31, 2019). We compared prepandemic health care utilization, status epilepticus, and mortality rates with corresponding pandemic rates for PWE and people without epilepsy (PWOE). We performed subgroup analyses on children (<18 years old), older people (>65 years old), those with intellectual disability, and those living in the most deprived areas. We used Poisson models to calculate adjusted rate ratios (RRs).

RESULTS

We identified 27 279 PWE who had significantly higher rates of hospital (50.3 visits/1000 patient months), emergency department (55.7), and outpatient attendance (172.4) when compared to PWOE (corresponding figures: 25.7, 25.2, and 87.0) in the prepandemic period. Hospital and epilepsy-related hospital admissions, and emergency department and outpatient attendances all reduced significantly for PWE (and all subgroups) during the pandemic period. RRs [95% confidence intervals (CIs)] for pandemic versus prepandemic periods were .70 [.69-.72], .77 [.73-.81], .78 [.77-.79], and .80 [.79-.81]. The corresponding rates also reduced for PWOE. New epilepsy diagnosis rates decreased during the pandemic compared with the prepandemic period (2.3/100 000/month cf. 3.1/100 000/month, RR = .73, 95% CI = .68-.78). Both all-cause deaths and deaths with epilepsy recorded on the death certificate increased for PWE during the pandemic (RR = 1.07, 95% CI = .997-1.145 and RR = 2.44, 95% CI = 2.12-2.81). When removing COVID deaths, RRs were .88 (95% CI = .81-.95) and 1.29 (95% CI = 1.08-1.53). Status epilepticus rates did not change significantly during the pandemic (RR = .95, 95% CI = .78-1.15).

SIGNIFICANCE

All-cause non-COVID deaths did not increase but non-COVID deaths associated with epilepsy did increase for PWE during the COVID-19 pandemic. The longer term effects of the decrease in new epilepsy diagnoses and health care utilization and increase in deaths associated with epilepsy need further research.

Epilepsy and the risk of COVID-19-related hospitalization and death: A population study

OBJECTIVE

People with epilepsy (PWE) may be at an increased risk of severe COVID-19. It is important to characterize this risk to inform PWE and for future health and care planning. We assessed whether PWE were at higher risk of being hospitalized with, or dying from, COVID-19.

METHODS

We performed a retrospective cohort study using linked, population-scale, anonymized electronic health records from the SAIL (Secure Anonymised Information Linkage) databank. This includes hospital admission and demographic data for the complete Welsh population (3.1 million) and primary care records for 86% of the population. We identified 27 279 PWE living in Wales during the study period (March 1, 2020 to June 30, 2021). Controls were identified using exact 5:1 matching (sex, age, and socioeconomic status). We defined COVID-19 deaths as having International Classification of Diseases, 10th Revision (ICD-10) codes for COVID-19 on death certificates or occurring within 28 days of a positive SARS-CoV-2 polymerase chain reaction (PCR) test. COVID-19 hospitalizations were defined as having a COVID-19 ICD-10 code for the reason for admission or occurring within 28 days of a positive SARS-CoV-2 PCR test. We recorded COVID-19 vaccinations and comorbidities known to increase the risk of COVID-19 hospitalization and death. We used Cox proportional hazard models to calculate hazard ratios.

RESULTS

There were 158 (.58%) COVID-19 deaths and 933 (3.4%) COVID-19 hospitalizations in PWE, and 370 (.27%) deaths and 1871 (1.4%) hospitalizations in controls. Hazard ratios for COVID-19 death and hospitalization in PWE compared to controls were 2.15 (95% confidence interval [CI] = 1.78-2.59) and 2.15 (95% CI = 1.94-2.37), respectively. Adjusted hazard ratios (adjusted for comorbidities) for death and hospitalization were 1.32 (95% CI = 1.08-1.62) and 1.60 (95% CI = 1.44-1.78).

SIGNIFICANCE

PWE are at increased risk of being hospitalized with, and dying from, COVID-19 when compared to age-, sex-, and deprivation-matched controls, even when adjusting for comorbidities. This may have implications for prioritizing future COVID-19 treatments and vaccinations for PWE.

COVID-19 vaccination uptake in people with epilepsy in wales

PURPOSE

People with epilepsy (PWE) are at increased risk of severe COVID-19. Assessing COVID-19 vaccine uptake is therefore important. We compared COVID-19 vaccination uptake for PWE in Wales with a matched control cohort.

METHODS

We performed a retrospective, population, cohort study using linked, anonymised, Welsh electronic health records within the Secure Anonymised Information Linkage (SAIL) Databank (Welsh population=3.1 million).We identified PWE in Wales between 1st March 2020 and 31st December 2021 and created a control cohort using exact 5:1 matching (sex, age and socioeconomic status). We recorded 1st, 2nd and booster COVID-19 vaccinations.

RESULTS

There were 25,404 adults with epilepsy (127,020 controls). 23,454 (92.3%) had a first vaccination, 22,826 (89.9%) a second, and 17,797 (70.1%) a booster. Comparative figures for controls were: 112,334 (87.8%), 109,057 (85.2%) and 79,980 (62.4%).PWE had higher vaccination rates in all age, sex and socioeconomic subgroups apart from booster uptake in older subgroups. Vaccination rates were higher in older subgroups, women and less deprived areas for both cohorts. People with intellectual disability and epilepsy had higher vaccination rates when compared with controls with intellectual disability.

CONCLUSIONS

COVID-19 vaccination uptake for PWE in Wales was higher than that for a matched control group.

146 Epilepsy, deprivation and mortality in Wales 2005–2017

Background

Public Health England have recently reported that deaths associated with epilepsy are increasing and are associated with increased deprivation. We investigated comparable Welsh mortality trends and associations between epilepsy mortality and deprivation.

Method

We used routinely-collected health data within the Secure Anonymised Information Linkage (SAIL) Databank. We recorded deaths associated with epilepsy (DAE), epilepsy recorded on death certificates, and deaths in people with epilepsy (DPWE), people with diagnoses of epilepsy and epilepsy prescriptions before death. We compared death rates in different deprivation deciles adjusting for epilepsy prevalence.

Results

During 2005–2017 (41million patient-years) there were 2116 DAE and 7821 DPWE. DAE and DPWE increased from 4.3/100,000/yr and 17.2/100,000/yr in 2005–2007 to 5.7/100,000/yr and 20.9/100,000/yr in 2015–2017. The age-standardised mortality rates (ASMR) in 2006–2008 for DAE and DPWE were 5.3/100,000/yr and 20/100,000/yr respectively, in 2015–2017 they were 5.8/100,000/yr and 20/100,000/yr. DAE were not significantly associated with deprivation when adjusted for epilepsy prevalence.

Conclusion

When adjusting for age, deaths associated wtih epilepsy and deaths in people with epilepsy did not increase significantly in Wales between 2005–2007 and 2015–2017. The association between dep- rivation and deaths associated with epilepsy appears to be explained by higher epilepsy prevalence in areas of higher deprivation.

w.o.pickrell@swansea.ac.uk

Automation of the collection and processing of X-ray diffraction data -- a generic approach

With modern detectors and synchrotron sources, it is now routine to collect complete data sets in 10-30 min. To make the most efficient use of these resources, it is desirable to automate the collection and processing of the diffraction data, ideally to a level at which multiple data sets can be acquired without any intervention. A scheme is described to allow fully automated data collection and processing. The design is modular, so that it can easily be interfaced with different beamline-control programs and different data-processing programs. An expert system provides a communication path between the data-processing software and the beamline-control software and takes decisions about the data collection based on project information provided by the user and experimental data provided by the data-processing program.

Factors influencing growth and final height after renal transplantation

Growth retardation occurs commonly in children and adolescents with chronic renal insufficiency. While some children exhibit catch-up growth following renal transplantation, for many children growth remains sub-optimal. The aim of the current study was to review the factors influencing growth and final height following renal transplantation. Data from all children who had a renal transplant performed between 1985 and 1998 at the Royal Melbourne and Royal Children's Hospitals, Melbourne (n = 85), were examined retrospectively. Two children who died in the first year post-transplant and one patient lost to follow-up within 6 months of their transplant were excluded. Children with multiple grafts had only growth following their most recent graft analyzed. The mean height standard deviation score (Ht-SDS) at the time of transplantation was -2.11 (range: -5.05 to 0.27), improving to -1.50 (range: -3.67 to 1.27) at 7 yr post-transplant. On univariate analysis, the dose of cyclosporin at 6 months and at 1 and 3 yr, and the graft function at 1 yr, had a significant positive correlation with the change in Ht-SDS (DeltaHt-SDS) at each of those time-points post-transplant. At all time-points there was a strong correlation between pretransplant height and subsequent growth. A sub-group of children who were 16 yr of age or older at December 1999, and who were considered to have reached their final height, were examined to determine predictors of final height. Multiple regression analysis of clinical and laboratory parameters from the sub-group of patients > or = 16 yr of age showed that height at the time of transplant, age at the time of transplant, and final glomerular filtration rate, were significant independent predictors of growth (r2 = 0.82, p = 0.01). In addition, the immunosuppressive regimen at 1, 3, and 5 yr post-transplant had a significant effect on growth. This study confirms the importance of each of these factors for post-transplant growth.

Clinical spectrum of Denys-Drash and Frasier syndrome

Denys-Drash syndrome (DDS) and Frasier syndrome (FS) are two related conditions caused by mutations of the Wilms tumor gene, WT1. Both syndromes are characterized by male pseudohermaphroditism, a progressive glomerulopathy, and the development of genitourinary tumors. DDS and FS have previously been distinguished by differences in nephropathy, with DDS patients demonstrating diffuse mesangial sclerosis (DMS) in contrast to focal and segmental glomerulosclerosis (FSGS) in FS patients. The clinicopathological features and genotype analysis of two patients with WT1 mutations are presented in this report. Genotype analysis of the first patient revealed a previously undescribed mutation in exon 8 of the WT1 gene. The second patient presented with a rapidly progressive nephropathy characterized histologically by DMS, but was found to have the genetic mutation seen in FS patients. A summary of all reported patients with the characteristic mutation associated with FS demonstrates the clinical overlap of this syndrome with DDS. This suggests that both these conditions should be considered as part of the spectrum of disease due to WT1 gene mutations rather than as separate diseases. Clinical classification remains important for prognosis, as the underlying renal disease appears to predict the progression of nephropathy independently of the genetic abnormality.

Evaluation and long-term outcome of pediatric renovascular hypertension

Seventeen children with renovascular hypertension were managed at the Royal Children's Hospital, Melbourne, over the 20-year period from 1975 to 1996. The age at presentation ranged from 10 days to 18 years. All children presented with severe hypertension with mean systolic blood pressure 7 standard deviations above age-matched averages and mean diastolic blood pressure 5.5 standard deviations above age-matched averages. Neurofibromatosis was the most common etiology (58% of patients) and there were no cases of Takayasu's arteritis. Patients underwent a variety of biochemical and imaging investigations but in all cases renal angiography was necessary for definitive diagnosis and for planning therapy. Ten of the 17 patients had surgical procedures performed. Percutaneous transluminal angioplasty was performed in four patients but led to cure in only one patient following thrombosis of the affected artery producing segmental renal infarction. Other vascular reconstructive procedures, including the use of autologous or synthetic bypass grafts and autotransplantation, produced cure of hypertension in 50% of children with improvement in a further 30%. The long-term outlook for children treated with surgical reconstructive procedures was excellent. One patient underwent surgery for avulsion of an arterial graft following a pubertal growth spurt. No other patient originally cured by surgery has required reoperation with no cases of restenosis at a mean follow-up of 11 years 3 months.

The Rossmann Fourier autoindexing algorithm in MOSFLM

The fast Fourier transform (FFT) autoindexing routines written by the Rossmann group at Purdue University have been incorporated in MOSFLM, providing a rapid and reliable method of indexing oscillation images. This is a procedure which extracts direct-space information about the unit cell from the FFT. The method and its implementation in MOSFLM are discussed.

Determination by MAD-DM of the structure of the DNA duplex d[ACGTACG(5-BrU)]2 at 1.46 A and 100 K

A four-wavelength MAD experiment on a new brominated octanucleotide is reported here. d[ACGTACG(5-BrU)], C77H81BrN30O32P7, Mr (DNA) = 2235, tetragonal, P43212 (No. 96), a = 43.597, c = 26.268 A, V = 49927.5 A3, Z = 8, T = 100 K, R = 10.91% for 4312 reflections between 15.0 and 1.46 A resolution. The self-complementary brominated octanucleotide d[ACGTACG(5-BrU)]2 has been crystallized and data measured to 1.45 A at both 293 K and a second crystal flash frozen at 100 K. The latter data collection was carried out to the same resolution at the four wavelengths 0.9344, 0.9216, 0.9208 and 0.9003 A, around the Br K edge at 0.92 A and the structure determined from a map derived from a MAD data analysis using pseudo-MIR methodology, as implemented in the program MLPHARE. This is one of the first successful MAD phasing experiments carried out at Sincrotrone Elettra in Trieste, Italy. The structure was refined using the data measured at 0.9003 A, anisotropic temperature factors and the restrained least-squares refinement implemented in the program SHELX96, and the helical parameters are compared with those previously determined for the isomorphous d(ACGTACGT)2 analogue. The asymmetric unit consists of a single strand of octamer with 96 water molecules. No countercations were located. The A-DNA helix geometry obtained has been analysed using the CURVES program.

The bi-loop, a new general four-stranded DNA motif

The crystal structure of the cyclic octanucleotide d<pATTCATTC> contains two independent molecules that form a novel quadruplex by means of intermolecular Watson-Crick A.T pairs and base stacking. A virtually identical quadruplex composed of G.C pairs was found by earlier x-ray analysis of the linear heptamer d(GCATGCT), when the DNA was looped in the crystal. The close correspondence between these two structures of markedly dissimilar oligonucleotides suggests that they are both examples of a previously unrecognized motif. Their nucleotide sequences have little in common except for two separated 5'-purine-pyrimidine dinucleotides forming the quadruplex, and by implication these so-called "bi-loops" could occur widely in natural DNA. Such structures provide a mechanism for noncovalent linking of polynucleotides in vivo. Their capacity to associate by base stacking, demonstrated in the crystal structure of d(GCATGCT), creates a compact molecular framework made up of four DNA chains within which strand exchange could take place.

Left ventricular abnormalities in children, adolescents and young adults with renal disease

The cardiac abnormalities that complicate chronic renal failure and renal replacement therapy are not well characterized in young people. These abnormalities are becoming more important because successful renal transplantation has resulted in children with end-stage renal failure living longer. Echocardiographic abnormalities of cardiac function and structure were studied in children and young adults (< 27 years old) with chronic renal failure (CRF, N = 32), end-stage renal failure treated with chronic peritoneal dialysis (CPD, N = 10) or renal transplantation (N = 30) or controls (N = 60). Left ventricular mass indexed for height (LVM/Ht and LVM/Ht2.7) and body surface area (LVM/SA), fractional shortening, measurement of left ventricular diastolic function (peak E and A wave velocities and the EA ratio) and structural (such as valvular) abnormalities were determined by echocardiography. The median (and range) of LVM/Ht in the groups were control 51.8 (23.1 to 119.8), CRF 60.2 (22.2 to 135.8), CPD 80.2 (14.5 to 100.9) and transplant group 97.8 (51.2 to 182.1) g/m. The increases in LVM/Ht, LVM/Ht2.7 and LVM/SA in the transplant group were significant (P < 0.01). The CRF group had significantly increased LVM/Ht2.7 and LVM/SA (P < 0.01). Systolic function was not significantly different between the groups. A significant correlation between creatinine and LVM indexed for height was found in the CRF group. Systolic or diastolic blood pressure could not be correlated with LVM indices in the transplant group. Changes in diastolic function were found (increased peak A wave velocity and decreased E/A ratios in the CRF and CPD groups, and increased peak E wave velocity in the transplant group). The study demonstrated that left ventricular hypertrophy is a frequent and often severe finding in children with chronic renal failure and those treated with renal replacement therapy. Factors other than hypertension and anaemia are important, and evidence was found for a link between serum creatinine and increased left ventricular mass prior to end-stage renal failure.

An extreme example of the neonatal form of Bartter's syndrome

A male infant is described who had polyuria over the 4 months of his life with urine volumes exceeding 1,000 ml/kg per day, severe serum electrolyte losses, metabolic alkalosis and increased plasma renin activity (56 ng/ml per hour). He had a normal blood pressure and glomerular filtration rate when fluid replete. The urine flow rate was about 25% of the glomerular filtration rate. Renal histology showed hyperplasia of the juxtaglomerular apparatus and abnormalities of the proximal tubules. The features of this case suggest an extreme form of Bartter's syndrome presenting from the first days of life.

Sonographic measurement of renal enlargement in children with acute pyelonephritis and time needed for resolution: implications for renal growth assessment

OBJECTIVE

Failure of a kidney to grow satisfactorily in childhood is evidence of renal disease. Because kidneys may enlarge during an episode of acute pyelonephritis, concomitant renal length measurements cannot be used as baselines for growth assessment. This study was designed to determine the degree of renal enlargement in children with acute pyelonephritis and the time the enlargement takes to resolve after treatment is started to find the optimum time for obtaining baseline measurements.

SUBJECTS AND METHODS

In a cohort study, 180 children younger than 5 years old with their first proven acute urinary tract infection, with or without pyelonephritis, had renal scintigraphy and sonography within 15 days of starting treatment. The presence of cortical defects on scintigrams indicated pyelonephritis. The lengths of kidneys with and without scintigraphic defects (i.e., with and without pyelonephritis) were compared, adjusting for age and sex, and the length of kidneys with defects was related to time elapsed between the start of treatment and sonography.

RESULTS

Ninety-nine kidneys (28%) in 77 children (43%) had scintigraphic defects. Kidneys with defects were an average of 3.2 mm longer than kidneys without defects. Length and time interval between treatment and sonography in kidneys with defects correlated negatively, with mean length approaching that of kidneys without defects by 10-11 days.

CONCLUSION

Kidneys with acute pyelonephritis initially increase in length but return to normal on average by the 11th day of treatment. If poor renal growth is used as an indication of renal disease, sonography should be delayed or repeated at least 2 weeks after the start of treatment to determine the length of the uninflamed kidney.

Renal transplantation in young children

AIMS

To review the outcome of renal transplantation in small children treated with triple immunosuppression at a single Australian centre.

METHODS

The medical records of all children under the age of five years undergoing renal transplantation from 1988 were reviewed. The duration of follow-up was 30 months (range 18-36).

RESULTS

Six children received seven renal allografts (five living-related [LR] and two cadaveric [CD]). They had a median age of 3.75 years (range 1.5-4.9) and weight of 11.6 kg (9.1-14.5) at the time of transplantation. All patients received an immunosuppressive regime involving cyclosporin A, azathioprine and prednisolone. There were no deaths. The only graft lost was a CD graft (severe acute rejection within one week of transplantation). Hypertension occurred in all recipients and usually required more than one antihypertensive drug for treatment. Renal function measured by serum median creatinine concentration (range) was 0.05 mmol/L (0.03-0.11) at three months (n = 6) and 0.10 mmol/L (0.07-0.22) at 30 months (n = 4). Growth estimated from median (range) height standard deviation scores was -1.97 (-1.36-(-4.04)) at three months (n = 6) and -1.90 (-1.74-2.50) at 30 months (n = 4). No patient was entirely weaned from prednisolone. Cyclosporin A side effects included hirsutism (five patients), gingival hyperplasia (six patients) and nephrotoxicity (three patients).

CONCLUSIONS

Satisfactory patient and graft survival can be accomplished in this recipient age group. The results compare with other international experience and accumulating Australian experience. Hypertension and poor skeletal growth were consistent observations. The long-term outcome of renal function using triple immunosuppression remains to be determined.

Familial hypomagnesaemia--hypercalciuria leading to end-stage renal failure

Several disorders of hypomagnesaemia of hetary renal origin are now recognised. The cases of two sisters from a consanguineous marriage with the syndrome of renal magnesium wasting, hypercalciuria and nephrocalcinosis are presented. Pathological examination of the heterozygous parental kidneys revealed mild focal interstitial fibrosis. This condition is a previously unreported cause of end-stage renal failure in childhood, and this report suggests that transplantation from heterozygous parental donors can be successfully undertaken without recurrence of the syndrome.

Tamm-Horsfall protein: are serum levels a marker for urinary tract obstruction?

Tamm-Horsfall protein (THP) has been found in the renal interstitium in patients with obstructive uropathy. The aim of this study was to investigate whether serum concentrations of THP could serve as a screening test for urinary tract obstruction. The presence of THP in normal human serum was confirmed by sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blotting. A specific enzyme immunoassay was then used to measure the serum concentration of THP. Serum THP concentrations were estimated in a cross-sectional study of a group of 23 patients who had technetium-99m-diethylene-triaminepenta-acetic acid (DTPA) nuclear urinary excretion studies to define urinary tract obstruction, and in longitudinal studies in 2 patients who developed acute bilateral ureteric obstruction following operations for ureteric reimplantation. The subjects with DTPA-proven urinary tract obstruction had higher concentrations of serum THP (n = 10, median = 43.9 ng/ml, range 10.4-152.1 ng/ml) than those who did not have obstruction (n = 13, median = 9.6 ng/ml, range 1.26-61.9 ng/ml). While this difference was significant (P < 0.01, Mann-Whitney U test), 6 of the 10 patients with obstruction had serum THP concentrations within the range of those patients without obstruction. The patients who developed acute bilateral ureteric obstruction both had increases in serum THP concentrations with obstruction and decreases in serum THP concentrations following relief of obstruction. These changes paralleled those in serum creatinine. The studies indicate that urinary tract obstruction results in increases in serum THP concentrations but these changes are not sufficient in magnitude to allow screening of children for urinary tract obstruction.

Risk factors in the development of early renal cortical defects in children with urinary tract infection

OBJECTIVE

Defects seen on early cortical scintigrams of the renal cortex in children with urinary tract infection may represent acute inflammatory change or established scar. The purpose of this study was to determine the relationship between these defects and age, sex, the presence and grade of vesicoureteral reflux, and infective organism in a cohort of children examined after their first proved urinary tract infection.

SUBJECTS AND METHODS

We prospectively examined 193 consecutive patients less than 5 years old who were seen at the ambulatory pediatric department during a 3-year period and had a first proved urinary tract infection. Children with obstructed or solitary kidneys were excluded. All patients were imaged with scintigraphy of the renal cortex and radiographic voiding cystourethrography within 15 days of diagnosis. The association of age, sex, the presence and grade of vesicoureteral reflux, and infective organism with a defect (acute pyelonephritis or a renal scar) seen on a cortical renal scan was studied.

RESULTS

The prevalence of cortical defects was greater in the kidneys of patients less than 2 years old (96/290, 33%) than in older children (16/96, 17%) and greater in those with vesicoureteral reflux (41/92, 45%) than in those without it (71/294, 24%). Vesicoureteral reflux was absent in 63% (71/112) of kidneys with a cortical defect. No association with sex or infective organism was established. As well as having a greater prevalence of cortical defects, 145 (75%) of the 193 urinary tract infections included in the study were in children less than 2 years old. The kidneys of these younger patients also had a greater severity and prevalence of vesicoureteral reflux (74/290, 26%) than did those of older children (18/96, 19%).

CONCLUSION

Early cortical defects are associated with an age less than 2 years and vesicoureteral reflux. However, the association of early defects with the presence and grade of vesicoureteral reflux is confounded by the declining prevalence and severity of reflux with age. A significant proportion of cortical defects occur in the absence of vesicoureteral reflux, and the contribution of reflux to scar formation might be less than previously considered.

The effect of growth hormone on growth and blood urea levels in children with chronic renal failure

It has been claimed that low protein diets slow deterioration of chronic renal failure (CRF) by reducing renal solute load. The anabolic effect of recombinant human growth hormone (rhGH) also has potential to reduce renal solute load and thereby slow progression of renal failure. The aim of this study was to determine the effect of rhGH on growth, renal solute load and renal function in children with CRF. Seven prepubertal children, aged 2-14 years, with moderately severe CRF (creatinine clearance 7.7-23.4 mL/min per 1.73m2) were treated with daily subcutaneous rhGH, 1 U/kg per week for 10-12 months. As expected, mean height velocity standard deviation scores (SDS) increased, from -2.87 before treatment to +3.39 on rhGH, and mean height increased from -3.1 to -2.4 SDS. Serum urea concentrations decreased in most patients during the first month of growth hormone treatment from a mean of 20.0 +/- 7.7 mmol/L to 14.8 +/- 5.8 mmol/L (P = 0.006). The serum urea then returned to pretreatment levels over the next few months. In the 12 months before treatment with growth hormone, mean creatinine clearance decreased from 19.3 mL/min per 1.73 m2 to 16.7 mL/min per 1.73 m2. In the next 12 months on rhGH mean creatinine clearance decreased further to 13.5 mL/min per 1.73 m2. Therefore the rate of deterioration of renal function was unaffected during treatment with growth hormone. Initial treatment with rhGH is associated with decrease in serum urea concentrations in children with CRF, probably mediated by stimulation of anabolic incorporation of dietary nitrogen into body protein.(ABSTRACT TRUNCATED AT 250 WORDS)

Triple immunosuppression with subsequent prednisolone withdrawal: 6 years' experience in paediatric renal allograft recipients

Thirty-four children (< or = 15 years of age) with end-stage renal failure received 39 renal allografts between 1985 and 1991 and were treated with cyclosporin A (CyA), azathioprine and low-dose prednisolone (PNL). We aimed to withdraw PNL by 6 months after transplantation. Median duration of follow-up was 2 years 4 months (range 0.1 month to 6 years 4 months). There were no deaths. Crude graft survival for living-related grafts (n = 9) was 100%, although only 1 patient has been followed for > 2 years. For cadaveric grafts (n = 30), 1- and 5-year actuarial graft survivals were 90% and 79% respectively. At 12 months posttransplant, the median (range) glomerular filtration rate for all patients was 63 (19-109) ml/min per 1.73 m2 (n = 25) and at 5 years was 48 (17-64) ml/min per 1.73 m2 (n = 9). Complications observed included rejection episodes which occurred after discontinuation of PNL. Long-term (after 12 months), 28% of patients remain on PNL. Hypertension was present in more than 50% of patients. Severe CyA nephrotoxicity was not seen. Catch-up growth as determined by the change (delta) in mean height standard deviation score (Ht-SDS) was noted at 1 year [delta SDS/year = +0.60; P < 0.001 (n = 18)] and at 2 years [delta SDS/year = +0.27; P < 0.01 (n = 16)] in pre-pubertal patients. The median Ht-SDS at 2 years for pre-pubertal children was -0.71 SD and growth velocity did not improve thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)

Vesicoureteral reflux: an accurate predictor of acute pyelonephritis in childhood urinary tract infection?

PURPOSE

To determine the association between vesicoureteral reflux (VUR) and the presence of acute pyelonephritis in children with urinary tract infections.

MATERIALS AND METHODS

The authors studied 150 consecutive patients less than 5 years of age with their first proved urinary tract infection. All patients underwent renal cortical scintigraphy (with technetium-99m dimercaptosuccinic acid or Tc-99m gluconate) and voiding cystourethrography (VCUG) to identify the presence of cortical defects and VUR, respectively.

RESULTS

Of 300 kidneys, 88 (29.3%) had a cortical defect at scintigraphy. Fifty-four of the 88 patients (61%) did not have VUR demonstrated at VCUG. Conversely, 72 of the 300 kidneys (24%) had VUR; of these, 38 (53%) had no cortical defect. The sensitivity of VCUG in helping predict a defect was 38.6%, and the specificity was 82.1%.

CONCLUSION

VUR (as shown by VCUG) and renal cortical scintigraphic defects frequently occur independently of each other. Renal cortical scintigraphy may be a more accurate predictor of patients at risk for scarring.

Recent advances in the management of vesico-ureteric reflux

Recent studies have demonstrated that both congenital hypoplasia and acquired scarring are involved in the parenchymal lesions associated with reflux nephropathy. Medical therapy can prevent symptomatic infection. While there is no proof that either medical or antireflux surgery prevents acquired scarring, paradoxically there is evidence that surgery adds no benefit to medical therapy, and that the results of medical therapy and surgical therapy are similar in children with isolated severe reflux. The group at most severe risk of renal scarring is infants and the effects of medical and surgical therapy in preventing acquired renal injury in this group have not been sufficiently investigated. On the basis of this information it has been our practice to maintain urine sterility using continuous antibiotic prophylaxis throughout infancy and early childhood. Following the development of reliable urine toilet habit and the ability to collect midstream urine specimens, antibiotics are given according to the frequency of urine infection, and weekly testing of morning urine with nitrite strips at home is used for early detection of infection and prevention of symptomatic infection. Antireflux surgery is mandatory for those children with complicated VUR (such as urinary tract obstruction) and should otherwise be reserved for those having persistent breakthrough infections in infancy and early childhood.

Paecilomyces variotii in peritoneal dialysate

Four cases of peritonitis caused by the filamentous fungus Paecilomyces variotii in patients on continuous ambulatory peritoneal dialysis are reported. Removal of the Tenckhoff catheter and antifungal chemotherapy led to resolution of symptoms in all cases. Possible contaminating events are discussed, and reported infections with P. variotii are reviewed.

Collagen studies in newborn rat kidneys with incomplete ureteric obstruction

Collagen studies in newborn rats with incomplete ureteric obstruction were performed to describe and quantify changes in collagen deposition resulting from urinary tract obstruction at an early developmental age. Incomplete ureteric obstruction was created in three-day-old rats by placing the left ureter in a tunnel formed by the psoas muscle, and sham-operated controls underwent a laparotomy. The rats were sacrificed at 10, 17, 24 or 31 days. Collagen types I, III, IV, and V were localized by indirect immunofluorescence microscopy, the total collagen content of the kidney was quantitated using hydroxyproline analysis, and collagen types I and III were quantitated using cyanogen bromide (CNBr) peptide analysis. Increased immunofluorescent staining for all of the collagens was found in the diffusely widened medullary interstitium of the obstructed kidney, and more focally in the cortical interstitium. Collagen types I, III and V, but not collagen type IV, were also found in bands in the interstitium at the junction of the cortex with the medulla. Increased staining for collagen type IV was found in thickened and tortuous tubular basement membranes (TBM) of the obstructed kidneys. The total collagen content of the obstructed kidney was significantly increased compared to the amounts in both the contralateral kidneys and in the kidneys from sham-operated controls at 24 and 31 days of age (P < 0.01 in each case, Wilcoxon matched pairs rank sum test and Mann Whitney U-test, respectively). The amount of collagen in the kidneys correlated with the degree of hydronephrosis (Spearman correlation test, r = 0.78, P < 0.02). CNBr peptide analysis demonstrated that over 50% of the collagen in the normal neonatal rat kidney was collagen type I and approximately 25% was collagen type III. In the obstructed kidneys most of the collagen was also collagen type I and collagen type III, although the proportion of total collagen comprised by these collagen types was decreased compared with the controls. The amount of collagen type III in the contralateral kidneys was reduced compared to that in the controls. Thus, the neonatal renal response to obstruction resulted in increased amounts of a range of collagens in the interstitium and TBM, and the extent of this response was partially related to the degree of hydronephrosis.

Kidney transplantation from living related donors: a 19-year experience

OBJECTIVE

To determine the outcome of patients with end-stage chronic renal failure treated by live donor renal transplantation at the Royal Melbourne Hospital and Royal Children's Hospital between 1973 and 1991, during which time two distinct immunosuppressive regimens were used.

DESIGN

Data about live donor renal transplant recipients were retrieved from the Australian and New Zealand Dialysis and Transplantation Association Registry, to which we have submitted data on all transplant recipients at six monthly intervals since the commencement of our dialysis and transplant programs.

PATIENTS

Seventy-two patients with chronic renal failure who received live donor renal transplants during the 19 years from February 1973 to February 1992 were included.

MAIN OUTCOME MEASURES

Patient survival, transplant survival, transplant function, change in prednisolone requirements, and duration of hospital stay.

RESULTS

The first 32 patients were treated with immunosuppressive regimens based on combinations of prednisolone and azathioprine ("dual therapy"), while the next 40 patients were treated with combinations of cyclosporin, prednisolone and azathioprine ("triple therapy"). Survival of patients in each group five years after transplantation was 97%. Actuarial graft survival at 5, 10 and 15 years in the dual therapy group was 58%, 52% and 47%, compared with a 5-year actuarial graft survival in the triple therapy group of 96%. There was no statistically significant difference in renal transplant function between the two groups within the first 6 years after transplantation. Twelve of 26 patients (46%) treated initially with triple therapy were able to stop treatment with prednisolone within 12 months of transplantation. Median hospital stay was 12 (range, 6-35) days during the period 1973-1985 and 8 (range, 5-20) days for the 1985-1992 period.

CONCLUSION

Live donor renal transplantation has provided a highly satisfactory means of treating patients with end-stage chronic renal failure in the short and long term. Our recent experience indicates that excellent patient and graft survival and adequate renal function can be achieved by treating live donor renal transplant recipients with a triple immunosuppressive regimen of low dose cyclosporin, prednisolone and azathioprine.

Anti-neutrophil cytoplasmic antibody-associated glomerulonephritis in children

Two cases of anti-neutrophil cytoplasmic antibody (ANCA)-associated necrotizing and crescentic glomerulonephritis are reported. A 12-year-old girl and a 10-year-old boy presented with polyarthritis, anaemia, haematuria, proteinuria, impaired renal function, anorexia, nausea, marked loss of weight and lethargy. The boy also had a vasculitic rash and anterior uveitis. Both children had diffuse cytoplasmic ANCA identified by indirect immunofluorescence and confirmed by specific enzyme-linked immunosorbent assay. Renal biopsies showed severe focal and segmental necrotizing glomerulonephritis with 100% crescents. They were treated with plasma exchange, prednisolone, cyclophosphamide and heparin. Within 1 month of commencing treatment, both had normal serum creatinine concentrations and ANCA was not detectable. Renal biopsies 6 weeks following commencement of treatment revealed quiescent disease, although up to 40% of glomeruli were sclerosed or had fibrous crescents. Following cessation of cyclophosphamide and heparin after 7 months and reduction in steroid dose, a biopsy at 10 months in the boy revealed quiescent disease, but the girl had recurrent disease associated with reappearance of a low titre of ANCA and small cellular crescents in 20% of the glomeruli. These cases reflect the potential usefulness of ANCA determination for categorizing paediatric patients, helping in the selection of therapy and as a possible marker of disease activity, similar to the experience in adults.

Recurrent haemolytic uraemic syndrome in a transplant recipient on orthoclone (OKT 3)

Recurrence of haemolytic-uraemic syndrome (HUS) after renal transplantation may occur in both cyclosporin A (CyA) and non-CyA-treated patients, and in patients receiving anti-lymphocyte globulin. We report a case of recurrent HUS in an 8-year-old boy who received Orthoclone (OKT3) combined with prednisolone and azathioprine therapy on receipt of his first cadaveric renal allograft. Despite avoidance of CyA therapy irreversible HUS occurred.

Polymeric IgA and immune complex concentrations in IgA-related renal disease

Polymeric IgA (PIgA) and immune complex concentrations in IgA-related renal disease were measured in cross sectional and longitudinal studies to establish the relationship between these parameters and both mucosal infection and renal dysfunction. These studies were performed in 50 patients with IgA nephropathy (IgAN), 17 patients with Henoch Schönlein purpura nephritis (HSPN), 11 control patients with IgA negative, diffuse mesangial proliferative glomerulonephritis (DMPGN) and 50 healthy controls. Total PIgA (PIgAT) and PIgA subclass concentrations were measured using a secretory component binding enzyme immunoassay and isotype specific immune complex concentrations were measured using conglutinin (K) binding immunoassays. In cross sectional studies patients with IgAN were found to have increased concentrations of PIgAT, PIgA1, K-IgA1 and K-IgA2 compared to controls. In the longitudinal studies controls and patients had significant increases in PIgAT and PIgA1 concentrations during infection. However, in patients with IgAN, the increases were greater, persisted for longer, and PIgA2 concentrations were also increased. K-IgA1 and K-IgA2 concentrations increased significantly during episodes of infection in IgAN patients in contrast to controls. Patients with HSPN had results similar to those of IgAN patients. No significant correlation was found between PIgA or K-IgA concentrations, and either serum creatinine concentrations or the degree of hematuria. The results indicate that patients with IgA-related renal disease have abnormal regulation of PIgA and immune complexed IgA, and that these abnormalities are exaggerated during mucosal infection.

Low red cell arachidonic acid in cyclosporine-treated patients

Red blood cell phospholipid arachidonic acid concentration was determined in 38 renal transplant recipients on cyclosporine-azathioprine-prednisolone therapy and in a comparable group of 20 patients on azathioprine-prednisolone alone. Samples also were obtained from 18 normal controls and 30 patients with "classical" hemolytic uremic syndrome (HUS). The arachidonic acid content was estimated as the percentage relative to the five principal fatty acids in red blood cell phospholipids (C16:0, C18:0, C18:1 omega 9, C18:2 omega 6, C18:3 omega 6) and quoted as mean value +/- standard deviation. There was a highly significant difference between patients on cyclosporine (14.7 +/- 2.9) and non-cyclosporine-treated transplant recipients (17.1 +/- 2.5; p less than 0.002). This difference was even more significant when patients who had been on cyclosporine for less than 3 months were excluded (14.1 +/- 2.7; p less than 0.001). The mean arachidonic acid content in non-cyclosporine recipients also was significantly less than that in normal controls (19.2 +/- 1.5; p less than 0.005) whilst the HUS patients (11.2 +/- 3.6) had significantly reduced values when compared with all the other groups. Cyclosporine often causes nephrotoxicity and in some cases HUS may develop in cyclosporine-treated transplant recipients. We have found a significant negative correlation between serum creatinine levels and red blood cell phospholipid arachidonic acid levels (r = -0.45; p less than 0.01). We propose that the decreased concentration of arachidonic acid in the cyclosporine-treated group may be related to the development of nephrotoxicity in the long term and may be a useful marker in predicting the early development of nephrotoxicity in these patients.

Antibodies to polyclonal IgA, IgA1, and IgA2 and isotype-specific immune complexes in IgA nephropathy

The concentrations of serum IgG and IgM antibodies to polyclonal IgA (IgAp), IgA1, and IgA2 were determined by enzyme immunoassay in 31 patients with IgA nephropathy and 30 healthy controls. Patients with IgA nephropathy had significantly raised concentrations of serum IgA compared to controls (Mann-Whitney U test, P = 0.001) and increased concentrations of conglutinin-binding IgA immune complexes (P = 0.024). No differences in the median concentrations of IgG and IgM anti-IgA antibodies were found between the patients and the controls. In serum samples from healthy controls there was a significant positive correlation between IgM anti-IgAp and IgA immune complex concentrations (P = 0.05), which contrasted with the finding of an inverse correlation between IgM anti-IgAp and IgA immune complex concentrations in patients with IgA nephropathy (P less than 0.05). In addition, the concentrations of conglutinin binding IgM immune complexes in serum were found to correlate with the concentration of IgM anti-IgAp (0.010 less than P less than 0.025), IgM anti-IgA1, and IgM anti-IgA2 (P much less than 0.005 for both) in patients with IgA nephropathy but not in controls. IgM anti-IgA antibodies may be important in augmenting the clearance of IgA immune complexes from the serum of patients with IgA nephropathy.

Glomerulocystic renal disease: ultrasound appearances

Renal and hepatic sonography were performed in 2 neonates with glomerulocystic renal disease. One neonate had ultrasound findings of normal hypoechoic medullary pyramids, enabling differentiation from infantile polycystic renal disease. Previous case reports have highlighted the similarity of renal ultrasound findings in these two conditions.

Cerebral infection with Escherichia coli O157:H7 in humans and gnotobiotic piglets

Escherichia coli O157:H7 was isolated from a fatal case of haemorrhagic colitis with haemolytic uraemic syndrome and neurological symptoms. This strain induced diarrhoea and neurological symptoms including incoordination, ataxia, and convulsions in piglets after oral inoculation. Similar neurological signs were seen in piglets inoculated intraperitoneally with bacterial extracts containing a shiga-like toxin that is elaborated by the bacteria. Histological examination of the brains from these piglets showed vascular damage and small infarcts confined to the cerebellum. Comparable lesions were also seen in the brain of the child from whom E coli O157:H7 was isolated. We suggest that the cerebral changes in the piglets and in the patient were caused by the shiga-like toxin elaborated by E coli O157:H7. The shiga-like toxin is thought to cause neurological abnormalities by damage to cerebral blood vessels rather than by a direct effect on the neurones.

Haemolytic-uraemic syndrome after treatment with metronidazole

This paper describes the clinical features of six children who developed the haemolytic-uraemic syndrome after treatment with metronidazole. These children were older and were more likely to have undergone recent bowel surgery than are other children with this condition. While the involvement of metronidazole in the aetiology of the haemolytic-uraemic syndrome is not established firmly, the action of this drug in sensitizing tissues to oxidation injury and the reported evidence of oxidation changes in the haemolytic-uraemic syndrome suggest a possible link between metronidazole treatment and some cases of the haemolytic-uraemic syndrome.

Paediatric cadaveric renal transplantation. Initial experience with a triple therapy immunosuppressive regimen

Since June 1985 ten consecutive paediatric cadaveric renal transplant recipients (aged from 7 to 15 years) have been studied prospectively to evaluate a triple immunosuppressive regime of low-dose cyclosporin A (CyA), azathioprine (AZA) and prednisolone (PNL) with the aim of eliminating PNL from the regime within 6 months. Follow-up has been over 6-18 months. Patient and graft survival are both 100%. Median (range) serum creatinine values at 6 months were 0.09 (0.05-0.14) mmol/l (n = 10) and 0.09 (0.06-0.16) mmol/l (n = 5) at 12 months. Readily reversible acute rejection episodes occurred in five patients (50%); two of these episodes occurred soon after cessation of PNL. Six months post-transplantation, PNL had been discontinued in six patients (60%). After 12 months, three of five patients were still not receiving PNL. Complications included hypertension (seven patients), cytomegaloviral infections (three patients), labial herpes simplex (one patient), leucopenia (two patients), marked hirsutism (four patients) and transient CyA nephrotoxicity (one patient). Following transplantation, all children had growth velocities greater than 5 cm/year and seven have growth patterns which suggest that "catch-up growth" may be occurring. This preliminary study shows that a triple immunosuppressive regime of low-dose CyA, AZA and PNL allows excellent patient survival, graft survival and graft function and has been associated with few complications, including a low incidence of CyA nephrotoxicity. Growth rates are very encouraging and in a high proportion of children it has been possible to discontinue PNL completely.

Urinary nitrite in symptomatic and asymptomatic urinary infection

The dipstrip test for urinary nitrite is fairly unreliable in symptomatic urinary infections and only 104 (52%) of 200 symptomatic children with urinary infection attending an emergency department had a positive result. The test yielded positive results, however, in 83 of 100 outpatients with largely asymptomatic urinary infection attending a follow up clinic because of known predisposition to urinary infection. This difference was highly significant. The finding of urinary nitrite is highly specific for urinary infection and only 1% of 300 uninfected urine specimens gave a positive result. After addition of a broth culture of Escherichia coli to sterile urine incubation at 37 degrees C for four to six hours was required before the nitrite test yielded positive results. This suggests that frequency of micturition in urinary infection reduces the reliability of the nitrite test. On the other hand, the use of overnight, first morning urine specimens may further improve the sensitivity. If nitrite testing is used for screening for urinary infection at home, however, patients should be warned not to rely on a negative result in the presence of symptoms of urinary infection.

Low red cell arachidonic acid in hemolytic uremic syndrome

A defect in prostacyclin generation has been proposed in hemolytic uremic syndrome (HUS): prostacyclin is formed from arachidonic acid derived from phospholipid and low levels of some phospholipids have been described in HUS cell membranes. Therefore fatty acid content of the red blood cell membranes of 8 children with HUS was compared with 32 children with other renal disease, with 33 patients with non-renal disease and with 8 normal adults. Children with HUS consistently had lower proportions of arachidonic acid (2.7-8.4%) than all other groups (10.1-18.8%) and the mean arachidonic acid level in HUS was very significantly reduced (p less than 0.0001). These findings suggest a reduced availability of arachidonic acid for prostaglandin synthesis in HUS and are consistent with the proposition that arachidonic acid is lost through peroxidative change.

Vitamin E treatment of haemolytic uraemic syndrome

Because low plasma vitamin E concentrations have been reported in patients with haemolytic uraemic syndrome and there is accumulating evidence of lipid peroxidation in this disease, treatment with the antioxidant vitamin E was undertaken in 16 consecutive children with the syndrome. Twelve children had features at presentation suggesting a poor prognosis for recovery but despite this all 16 patients survived and are well three months later. Fifteen children now have normal values for serum creatinine, blood pressure, and urinalysis for protein but one has slight renal impairment. Although this is not a report of a controlled trial, it seems that patients treated with vitamin E have fared considerably better than our previously treated patients with haemolytic uraemic syndrome, even in the presence of early, adverse prognostic features. We suggest that vitamin E alters the natural history of the disease, and in view of the absence of any observed side effects further experience with this treatment is being sought.

Response to frusemide in acute renal failure: dissociation of renin and diuretic responses

Eight hypertensive children with acute post-streptococcal glomerulonephritis were given intravenous frusemide, 2 mg/kg, and the results compared with 8 similar cases not given the diuretic. Mean urine flow increased from 0.24 ml/min/m2 before frusemide to 3.63 ml/min/m2 in the 6 hours afterwards and was still 0.72 ml/min/m2 48 hours later. In contrast mean urine flow remained unchanged over 48 hours in those not given frusemide. Despite similar initial blood pressures the duration of hypertension was much shorter (mean 4.7 days) after frusemide than in the controls (mean 11.0 days) and the edema-free weight was achieved more rapidly (6.8 days compared with 13.9 days). Plasma renin activity (PRA) did not rise after frusemide in the children with acute nephritis. This was in contrast to the rapid rise seen in normal humans thus indicating a dissociation between the diuretic and renin-releasing activities of frusemide in acute nephritis. Seven children with the hemolytic-uremic syndrome or acute tubular necrosis showed no significant change in either urine flow or PRA after frusemide. Frusemide is therefore effective treatment for both hypertension and oliguria in acute nephritis. Failure of PRA to rise indicates that renin release mechanisms are abnormal in renal failure and that PRA levels need to be interpreted with caution in this condition.

Renin release by parathyroid hormone in the dog

Synthetic N-terminal 34 amino acid peptide of bovine parathyroid hormone (PTH) produced a consistent rise in plasma renin activity in saline-loaded dogs when given iv either as a single bolus dose of 400 U or infused steadily in lower dosage over a number of hours. Infusion of as little as 1 U/min produced a significant rise in plasma renin activity, but a greater effect was obtained with 2 U/min. Infusion of 4 U/min had no more effect than 2 U/min. In contrast to transient hypotension after rapid injection of a single large dose, blood pressure did not change significantly during the steady infusion of lower doses of PTH. These findings are compatible with the thesis that an increased distal tubular load of sodium stimulates renin release and suggest that the increased distal sodium absorption after the proximal effects of PTH may be regulated by the renin-angiotensin-aldosterone system.

Nephropathy in cyanotic congenital heart disease

Three children with cyanotic congenital heart disease who developed transient proteinuria and edema are described. One died of an intercurrent illness but the other two are now well. Renal biopsy findings in all three children demonstrated a mesangial proliferative glomerulonephritis on light microscopy. An unusual ultrastructural appearance of localized electron-dense thickening of the basement membrane of the capillary loops was seen in all three and collagen fibers were present in the mesangium of two. There was slight fusion of foot processes in two specimens and marked fusion in the third. Immunofluorescence in two patients demonstrated IgM staining in both and fibrin in one. The cause of the glomerular lesions is unknown but, among the many possible factors involved, anoxia and increased venous pressure may be important.

Trends in freeze-drying equipment and materials

The above discussion outlines some trends seen in the development of equipment for freeze-drying of various biological-like products. It has been pointed out that many similarities in equipment now exist. There are still areas in which a consensus on best design has not been reached and in these areas the user is offered some clear choices. Various changes have been introduced in recent years into freeze-drying equipment principally in an effort to increase reliability and improve the quality of the product produced. It is probable as more products are freeze-dried (and particularly as these products become more cost-sensitive) that manufacturers will also require that greater performance-capability be built into their equipment. This may perhaps translate into requirements for carrying high peak-vapor-rates and for automatic control in an effort to reduce drying cycles and increase throughput in a given machine.

Diphosphonate therapy in nephrocalcinosis

4 patients with nephrocalcinosis were treated with disodium ethane 1-hydroxy-1, 1-diphosphonate (EHDP) for a period of 13 months. No clinical side-effects were observed and growth proceeded normally. Radiographic changes of osteitis fibrosa cystica developed in 1 child and bone biopsy in 2 children showed defective osteoid mineralisation. It is suggested that EHDP prevented further crystal deposition in 3 children but did not prevent non-calcium stone formation in the 4th child. In view of this and the development of histological and radiographic evidence of osteomalacia and/or secondary hyperparathyroidism in these patients the value of EHDP remains dubious. On the other hand its use may be justified when rapidly increasing calcification is expected, as for example in hyperoxaluria.

Relationship between proteinuria and epithelial cell changes in minimal lesion glomerulopathy

The degree of fusion of glomerular epithelial cell foot processes was quantitated by determining the mean number of inter-process slip pores along 10 mum of basement membrane of peripheral capillary walls in 45 children with steroid-responsive nephrotic syndrome and minimal lesion glomerulopathy. Fusion was present in all biopsies performed when the child had proteinuria, but after remission the number of slit pores increased progressively towards normal over the next 4 weeks. There was a close correlation between the degree of fusion and the amount of proteinuria in those biopsied before remission.