A Large Inversion Involving GNAS Exon A/B and All Exons Encoding Gsα Is Associated With Autosomal Dominant Pseudohypoparathyroidism Type Ib (PHP1B).

Pseudohypoparathyroidism type Ib (PHP1B) is characterized primarily by resistance to parathyroid hormone (PTH) and thus hypocalcemia and hyperphosphatemia, in most cases without evidence for Albright hereditary osteodystrophy (AHO). PHP1B is associated with epigenetic changes at one or several differentially-methylated regions (DMRs) within GNAS, which encodes the α-subunit of the stimulatory G protein (Gsα) and splice variants thereof. Heterozygous, maternally inherited STX16 or GNAS deletions leading to isolated loss-of-methylation (LOM) at exon A/B alone or at all maternal DMRs are the cause of autosomal dominant PHP1B (AD-PHP1B). In this study, we analyzed three affected individuals, the female proband and her two sons. All three revealed isolated LOM at GNAS exon A/B, whereas the proband's healthy maternal grandmother and uncle showed normal methylation at this locus. Haplotype analysis was consistent with linkage to the STX16/GNAS region, yet no deletion could be identified. Whole-genome sequencing of one of the patients revealed a large heterozygous inversion (1,882,433 bp). The centromeric breakpoint of the inversion is located 7,225 bp downstream of GNAS exon XL, but its DMR showed no methylation abnormality, raising the possibility that the inversion disrupts a regulatory element required only for establishing or maintaining exon A/B methylation. Because our three patients presented phenotypes consistent with PHP1B, and not with PHP1A, the Gsα promoter is probably unaffected by the inversion. Our findings expand the spectrum of genetic mutations that lead to LOM at exon A/B alone and thus biallelic expression of the transcript derived from this alternative first GNAS exon. © 2017 American Society for Bone and Mineral Research.

Prednisone in the treatment of tubulointerstitial nephritis in children.

BACKGROUND: Patients with tubulointerstitial nephritis (TIN) may develop permanent renal impairment. However, there are no prospective studies available on the treatment of TIN. METHODS: The effect of prednisone in the treatment of TIN was evaluated in a total of 17 patients who received prednisone or who were followed up without medication. The patient group was subdivided based on the initial plasma creatinine (PCr), below or above 150 µmol/l. RESULTS: All prednisone-treated patients had normal plasma creatinine (PCr) after 1 month of treatment (median 59.1 [45-85] µmol/l) whereas only 50 % of patients in the non-treatment group had normal creatinine (median 81.0 [42-123] µmol/l) at the same time point (p = 0.025). During 6 months' follow-up, PCr decreased in all patient groups; however, it decreased significantly only in prednisone-treated patients with baseline PCr >150 µmol/l (p < 0.001). At the end of follow-up, no difference in PCr, glomerular filtration rate (GFR), or low molecular weight (LMW) proteinuria could be found between the study groups. A considerable number of patients in both groups had subnormal GFR and/or persistent LMW proteinuria at the 6-month follow-up visit. Eighty-two percent of the patients had uveitis. CONCLUSIONS: Prednisone speeds up the recovery from renal symptoms of TIN, especially in patients with severe nephritis. The renal function did not differ significantly between prednisone and control patients after 6 months' follow-up.

Tubulointerstitial nephritis and uveitis syndrome in children: a prospective multicenter study.

PURPOSE: To evaluate the occurrence and characteristics of uveitis related to tubulointerstitial nephritis (TIN) in children. DESIGN: Prospective, observational, multicenter, partly placebo-controlled treatment trial. PARTICIPANTS: Nineteen children with a biopsy-proven TIN. METHODS: Patients were treated with prednisone or followed without treatment. In addition to the nephrologic evaluations, the prospective follow-up included structured ophthalmological examinations at the onset of TIN and at 3 and 6 months after the diagnosis. MAIN OUTCOME MEASURES: Occurrence, clinical features, and outcome of uveitis. RESULTS: Some 84% (16/19) of the patients had uveitis, 83% (5/6) in the nontreatment group and 82% (9/11) in the prednisone-treated group. The remaining 2 patients, originally in the nontreatment group, were switched to the prednisone group after 2 weeks. Both of them developed uveitis. Altogether, 3 patients developed uveitis during prednisone treatment and 2 patients showed worsening of uveitis despite the systemic corticosteroid. Some 50% (8/16) of the patients with uveitis presented with no ocular symptoms; 88% (14/16) of the patients had a chronic course of uveitis. Two patients were diagnosed with uveitis before nephritis; nephritis and uveitis were diagnosed within 1 week from each other in 7 patients, and uveitis developed 1 to 6 months after the diagnosis of TIN in 7 patients. CONCLUSIONS: There was no statistically significant difference in the occurrence of uveitis in patients with TIN in the prednisone and nontreatment groups. In this study, the occurrence of uveitis associated with TIN was considerably higher than previously reported. Uveitis related to TIN may develop late and is often asymptomatic. The ophthalmological follow-up of all patients with TIN is warranted for at least 12 months starting with 3-month intervals. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any material discussed in this article.

[Cystic kidney disease and diabetes--an underdiagnosed monogenic developmental disorder]. / Kystinen munuaissairaus ja diabetes--alidiagnosoitu yksigeeninen kehityshäiriö.

Heterozygous mutations in the TCF2 gene encoding the transcription factor HNF-11 cause a dominantly inherited developmental disorder that may be associated with various dysplastic and cystic lesions of the kidneys and renal insufficiency, disorder of pancreatic development and insulin-deficient MODY diabetes, aberrant hepatic enzyme levels, gout and genital anomalies. Symptoms and findings vary in their degree of severity. When an isolated abnormality is detected, recognition of the syndrome is essential in order to diagnose the other organ manifestations. Since the mid-2000's, 10 to 20 patients have been diagnosed in Finland.

Outcome of Henoch-Schönlein purpura 8 years after treatment with a placebo or prednisone at disease onset.

BACKGROUND: Corticosteroids have been shown not to prevent the development of Henoch-Schönlein nephritis. However, long-term follow-up data are scarce. METHODS: The long-term outcome of patients in a randomized placebo-controlled prednisone study was evaluated 8 years later with a health questionnaire completed by 160/171 (94%) patients and by urine and blood pressure screening (138/171, 81%). RESULTS: Twelve patients had hematuria and/or proteinuria and seven had hypertension. The patients with nephritis at onset of Henoch-Schönlein purpura (HSP) had an increased risk of hypertension and/or urine abnormalities (odds ratio 3.6, p = 0.022, 95% confidence interval 1.3-10.0). There were no differences between the prednisone and placebo groups. Recurrences of purpura were reported by 15 patients, with some recurrences continuing for 10 years. All five reported pregnancies were complicated by proteinuria. Four patients presented with hematuria and/or proteinuria at the control visit, and four had hypertension. Of these, two had a decreased estimated glomerular filtration rate. CONCLUSIONS: HSP has a good long-term prognosis in unselected patients, although skin relapses with/without late-onset nephritis may occur, even a decade after the initial disease. Urine and blood pressure abnormalities 8 years after HSP are associated with nephritis at its onset. Early prednisone treatment does not affect the outcome and should not be routinely used.

Cyclosporine A vs. methylprednisolone for Henoch-Schönlein nephritis: a randomized trial.

Knowledge about how to treat severe Henoch-Schönlein nephritis (HSN) is scarce. The aim of our study is to compare cyclosporine A (CyA) and methylprednisolone pulses (MP) in the treatment of severe HSN. Out of 24 pediatric HSN patients with nephrotic-range proteinuria or crescentic HSN in kidney biopsy, seven were randomized to receive CyA for 12 months at an initial dose of 5 mg/kg and eight to receive 3 MP pulses of 30 mg/kg followed by prednisone for 4 months. The other nine patients received identical treatment without randomization. Kidney biopsies were performed at inclusion and after 2 years. The primary outcomes were the duration of proteinuria and hematuria, estimated glomerular filtration rate, and renal biopsy histology. All the 11 CyA-treated patients achieved resolution of nephrotic-range proteinuria within 3 months, while the MP-group response was slower, and in 6/13 was not achieved with the initial treatment. Additional immunosuppressive treatment was needed in none of the CyA-treated patients but in six patients treated with MP (difference in proportion 46%, p = 0.008). The 2-year control biopsies were similarly improved in both groups. After mean 6.1 years (2.2-10.4 years), 16 patients (eight CyA, eight MP) had no renal symptoms and six (three CyA, three MP) had persistent nephropathy but normal renal function. One MP-treated patient had reduced renal function and another had developed ESRD and received a renal transplant. CyA gave a 100% resolution of nephrotic-range proteinuria and a 100% renal survival rate without additional therapy after a mean follow-up of 6 years. Treatment of HSN with CyA is efficacious, safe and not inferior to MP.

Clinical outcome and occurrence of uveitis in children with idiopathic tubulointerstitial nephritis.

Acute idiopathic tubulointerstitial nephritis (TIN) is considered a condition with a good long-term prognosis. However, there is evidence that some patients develop permanent renal impairment. The aim of this study was to evaluate the clinical characteristics of TIN at the time of diagnosis in children and determine whether the findings upon presentation predict renal outcome. The clinical data and biopsy findings from 26 children with idiopathic TIN admitted to four Finnish university hospitals were analyzed retrospectively. Twenty-five patients (96%) manifested renal insufficiency. After the mean follow-up time of 2.75 years (SD 2.5; 0.9-13.5), 4 patients (15%) had permanent renal insufficiency and 8 patients (31%) had persistent low-molecular weight proteinuria. Uveitis was found in 12 patients (46%). Four of these patients (33%) developed chronic uveitis. Our analysis showed that none of the laboratory or biopsy findings upon presentation prognosticated renal outcome. No correlation between renal disease and uveitis could be found either. The occurrence of uveitis among TIN patients was higher than previously reported. Uveitis may develop late and without recurrence of renal dysfunction. Therefore, follow-up by a pediatrician and by an ophthalmologist is warranted in children with acute TIN for at least 12 months from diagnosis.

Renal manifestations of Henoch-Schonlein purpura in a 6-month prospective study of 223 children.

OBJECTIVE: To assess the risk factors for developing Henoch-Schönlein purpura nephritis (HSN) and to determine the time period when renal involvement is unlikely after the initial disease onset. DESIGN: A prospective study of 223 paediatric patients to examine renal manifestations of Henoch-Schönlein purpura (HSP). The patient's condition was monitored with five outpatient visits to the research centre and urine dipstick testing at home. RESULTS: HSN occurred in 102/223 (46%) patients, consisting of isolated haematuria in 14%, isolated proteinuria in 9%, both haematuria and proteinuria in 56%, nephrotic-range proteinuria in 20% and nephrotic-nephritic syndrome in 1%. The patients who developed HSN were significantly older than those who did not (8.2±3.8 vs 6.2±3.0 years, p<0.001, CI for the difference 1.1 to 2.9). Nephritis occurred a mean of 14 days after HSP diagnosis, and within 1 month in the majority of cases. The risk of developing HSN after 2 months was 2%. Prednisone prophylaxis did not affect the timing of the appearance of nephritis. The risk factors for developing nephritis were age over 8 years at onset (OR 2.7, p=0.002, CI 1.4 to 5.1), abdominal pain (OR 2.1, p=0.017, CI 1.1 to 3.7) and recurrence of HSP disease (OR 3.1, p=0.002, CI 1.5 to 6.3). Patients with two or three risk factors developed nephritis in 63% and 87% of cases, respectively. Laboratory tests or blood pressure measurement at onset did not predict the occurrence of nephritis. CONCLUSION: The authors recommend weekly home urine dipstick analyses for the first 2 months for patients with HSP. Patients with nephritis should be followed up for more than 6 months as well as the patients with HSP recurrence.

Clinical course of extrarenal symptoms in Henoch-Schonlein purpura: a 6-month prospective study.

OBJECTIVE: To describe the extrarenal symptoms and clinical course of Henoch-Schönlein purpura (HSP). DESIGN: A prospective national multicentre trial with 6-month follow-up. Patients A total of 223 newly diagnosed paediatric HSP patients. RESULTS: Purpura was the initial symptom in 73% of the patients and was preceded by joint or gastrointestinal manifestations in the rest by a mean of 4 days. Joint symptoms, abdominal pain, melena, nephritis and recurrences occurred in 90%, 57%, 8%, 46% and 25% of the patients, respectively. Orchitis affected 17/122 (14%) of the boys. Seven patients developed protein-losing enteropathy characterised by abdominal pain, oedema and serum albumin under 30 g/l, and an additional 49 patients had subnormal albumin levels without any proteinuria. Positive fecal occult blood (26/117, 22%) and α1-antitrypsin (7/77, 9%) suggested mucosal injury even in the patients without gastrointestinal symptoms. HSP was often preceded by various bacterial, especially streptococcal (36%) and viral infections. Previous streptococcal infection did not induce changes in the level of complement component C3. Recurrences were more frequent in patients >8 years of age (OR 3.7, CI 2.0 to 7.0, p<0.001) and in patients with nephritis (OR 4.6, CI 2.3 to 8.9, p<0.001). Patients with severe HSP nephritis had more extrarenal symptoms up to 6 months. There was no difference in the clinical course between the prednisone-treated and non-treated patients during the 6-month follow-up. CONCLUSIONS: Serum albumin is often low in HSP patients without proteinuria, due to protein loss via the intestine. Although corticosteroids alleviate the symptoms, they seem not to alter the clinical course of HSP during 6 months of follow-up.

Diet does not explain the high prevalence of dyslipidaemia in paediatric renal transplant recipients.

Dyslipidaemia exists frequently after renal transplantation (RTx) and promotes atherosclerosis. In this study, we examined the association between daily intake of nutrients and serum lipids after paediatric RTx. We studied 45 children with acceptably functioning kidney grafts and adequately completed food records at a median age of 10.6 years (range 4.3-17.2 years), a median 5.2 years (range 1.0-11.0) after RTx, and 178 healthy controls at a median age of 9.0 years (range 3.2-18.7 years). Serum total cholesterol (TC), triglyceride, and apolipoprotein B concentrations were higher in the RTx patients than in the controls (P < 0.001), despite similar dietary intakes of saturated and polyunsaturated fats, and cholesterol. Both the RTx patients and controls ingested a low amount of polyunsaturated fats [mean (SD) percent of total calories (E%) 4.8 (1.3) and 4.6 (1.5), respectively] and an excessive amount of saturated fats [mean (SD) E% 14.4 (2.4) and 14.1 (2.8), respectively]. In multiple regression analyses, dietary fibre was negatively associated with serum TC concentration. The standard deviation score for body mass index was negatively associated with serum concentration of high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein diameter, and positively with serum triglyceride concentration. In addition, dietary total fat intake was positively associated with serum HDL-C. In conclusion, the higher prevalence of dyslipidaemia in our paediatric RTx patients than in the controls was not explained by the diet. However, the type of fat consumed implicates the counselling for a healthier dietary lifestyle, with an increase in the ingestion of polyunsaturated fats and a decrease in that of saturated fats.

Bone mineral density is reduced in brain tumour patients treated in childhood.

AIM: To determine the prevalence of low bone mineral density among children surviving brain tumours and to identify possible factors underlying impaired bone health. METHODS: Cross-sectional study; total body bone mineral density (TBBMD), fat mass (FM) and lean body mass (LBM) were measured by dual-energy X-ray absorptiometry (DXA) in 46 brain tumour patients aged from 3.8 to 28.7 y (mean 14.9 y) treated in childhood 1.4-14.8 y (mean 6.4 y) after end of treatment for brain tumour. Low bone mineral density was defined as TBBMD z score < - 2.0. RESULTS: Fifteen patients had TBBMD z scores < - 2.0, indicating a 33% prevalence of low bone density. The TBBMD z score ranged from -5.7 to 0.6 (mean -1.7). Out of several potential factors, only combined craniospinal irradiation was significantly associated with low z score (p=0.034, according to multiple regression analysis), while exclusive cranial irradiation showed a borderline statistical association (p=0.100, according to multiple regression analysis). CONCLUSION: One third of brain tumour patients treated in childhood had reduced bone mineral density. The reasons for this condition are apparently multifactorial, including craniospinal irradiation.

Early prednisone therapy in Henoch-Schönlein purpura: a randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To evaluate the efficacy of early prednisone therapy in preventing renal and treating extrarenal and renal symptoms in Henoch-Schönlein purpura (HSP) in a placebo-controlled trial. STUDY DESIGN: A total of 171 patients (84 treated with prednisone and 87 receiving placebo) were included and followed up for 6 months. The endpoints were renal involvement at 1, 3, and 6 months and healing of extrarenal symptoms. The analyses were performed on an intent-to-treat basis. RESULTS: Prednisone (1 mg/kg/day for 2 weeks, with weaning over the subsequent 2 weeks) was effective in reducing the intensity of abdominal pain (pain score, 2.5 vs 4.8; P = .029) and joint pain (4.6 vs 7.3; P = .030). Prednisone did not prevent the development of renal symptoms but was effective in treating them; renal symptoms resolved in 61% of the prednisone patients after treatment, compared with 34% of the placebo patients (difference = 27%; 95% confidence interval = 3% to 47%; P = .024). CONCLUSIONS: The general use of prednisone in HSP is not supported, but patients with disturbing symptoms may benefit from early treatment, because prednisone reduces extrarenal symptoms and is effective in altering (but not preventing) the course of renal involvement.

Long-term outcome 19 years after childhood IgA nephritis: a retrospective cohort study.

We evaluated the natural long-term outcome after childhood IgA nephritis. Altogether 55 patients with biopsy-proven IgA nephritis were identified, 37 (67%) responded to the health questionnaire and 31 (56%) participated in the medical examination after a mean follow-up of 18.7 years (SD 6.2; range 8.5-29.8). The results of medical examination, onset data and the re-analysis of original biopsies of 31 participants were used when analyzing the predictive factors for persistent nephropathy, i.e. constant proteinuria/hematuria or end-stage renal disease (ESRD). All patients' medical history data were obtained from regional hospitals and renal survival data from the national kidney register. Six (11%) of the 55 identified patients had developed ESRD. Sixteen (52%) of the 31 participants were not attending for regular follow-up visits after the acute phase. Twenty-two (71%) had renal symptoms and 12 (39%) were receiving drugs for hypertension/proteinuria at their latest follow-up visit. The chronicity index and total biopsy score in the first renal biopsy were higher in patients with persistent nephropathy or ESRD than in those without (p=0.022 and p=0.014, respectively). Nine (69%) of the 13 subjects who had been over 16 years of age at diagnosis had persistent nephropathy or ESRD, compared with 4 (22%) of the 18 subjects who had been under 16 years of age (relative risk 3.1, 95% CI 1.2-8.0). Pregnancy complications were common: 12 (55%) of the 22 pregnancies had been complicated by proteinuria and/or hypertension, and the prematurity rate was 30%. Long-term follow-up during adulthood is needed even after mild childhood IgA nephritis, especially in women during and after pregnancy.

Tubular proteinuria in pre-term and full-term infants.

Predictors of tubular proteinuria (alpha 1-M/crea ratio >10 mg/mmol) were sought in 100 infants of 24-32 weeks' (group 1) and 69 of 34-42 weeks' gestation (group 2). Random spot urine samples were obtained in the former group at the ages of 0-3 days, at 1-2 weeks and thereafter at 2-week intervals until the disappearance of tubular proteinuria, and in the latter one sample at a mean (SD) of 3.0 days' (1.3) age. In group 1, gestational age correlated negatively with the first urinary alpha 1-M/crea ratio. The highest urinary alpha 1-M/crea ratios [median (range) 39.1 mg/mmol (9.5-268.9)] occurred at a median (range) of 5 days' (1-42) age. Low gestational age and the need for inotropes predicted tubular proteinuria early after birth, whereas low gestation and long duration of ventilator treatment predicted the highest alpha 1-M/crea ratios. Prolonged vancomycin treatment and low gestational age were associated with delayed normalization of tubular proteinuria. In group 2 no significant risk factors for tubular proteinuria were found. The urinary alpha 1-M/crea ratio seems to be a sensitive indicator of renal tubular function in neonates, with low gestational age, the need for inotropes and prolonged assisted ventilation being predictors of increased tubular proteinuria. Long vancomycin courses should be avoided in pre-term infants in view of the prolonged adverse renal effects.

Muscular dystonia and athetosis in six patients with congenital nephrotic syndrome of the Finnish type (NPHS1).

Congenital nephrotic syndrome of the Finnish type (NPHS1, CNF) is an autosomal recessively inherited disease occurring due to mutations in the nephrin gene (NPHS1). Two main Finnish mutations exist: Fin-major and minor, which both cause a lack of nephrin and absence of the slit diaphragm between the podocytes. This leads to severe proteinuria, nephrotic syndrome and infections, and without dialysis or renal transplantation, death in infancy. Between 1984 and 2003, six (8.6%) of the 70 NPHS1 patients diagnosed at our institution had, in addition to their renal disease, similar neurological symptoms. All six showed a severe dyskinetic cerebral palsy-like syndrome with dystonic features, athetosis and a hearing defect. The neurological symptoms became apparent during their 1st year of life and were diagnosed before 11 months of age. MRI showed increased signal intensity in T2-weighted images in the globus pallidus area. No mitochondrial gene mutations explaining the neurological symptoms were found, nor did external neurological complications explain them when compared with 29 NPHS1 control patients. Four children died at an early age: two during dialysis and two shortly after renal transplantation. Two are still alive with a functioning graft. Both have severe motor defects, but are mentally active and social.

Insulin resistance, LDL particle size, and LDL susceptibility to oxidation in pediatric kidney and liver recipients.

BACKGROUND: Dyslipidemia is common after solid organ transplantation. We have described hypertriglyceridemia in about 50% of our pediatric kidney, and in about 30% of our liver recipients. The aim of the present study was to find out whether this post-transplantation hypertriglyceridemia after pediatric solid organ transplantation is associated with insulin resistance and the occurrence of small, dense low-density lipoprotein (LDL). METHODS: Fifty kidney and 25 liver recipients (aged 4 to 18 years) on triple immunosuppression, and 181 control children participated in the study for an average of 5.3 and 6.4 years after kidney and liver transplantation (range 1 to 11 years), respectively. Homeostasis model assessments for insulin resistance (HOMA) were calculated and fasting lipoprotein lipid profile, apolipoprotein A-I and B concentrations, LDL particle diameter, and indices of LDL susceptibility to copper-induced oxidation determined. RESULTS: Kidney patients had significantly higher serum total, high-density, and low-density lipoprotein cholesterol, triglyceride, apolipoprotein A-I and B concentrations than liver patients or control subjects (P < 0.003 for all). HOMA indices higher than the 95th percentile of Canadian normal children were seen in 50.0% of kidney (of liver 41.2%) recipients younger than 11 years, and in 27.3% of older recipients (of liver 37.5%). Smaller sized LDL or LDL of increased oxidizability was not more frequent in patients than in control children. CONCLUSION: Pediatric kidney recipients had significantly higher lipid and insulin concentrations than healthy control children. Combined hyperlipidemia and features of the dysmetabolic syndrome were common in children after kidney and liver transplantation. However, no small, dense LDL, or LDL prone to oxidation was seen in either group.