Primary ovarian insufficiency in RMND1 mitochondrial disease.

RMND1 (Required for Meiotic Nuclear Division 1 homolog) is a nuclear encoded mitochondrial protein. Biallelic variants inRMND1are described in patients with white matter encephalopathy, hearing loss and renal dysfunction. In addition to this phenotype, two independent families (3 patients) have been reported with ovarian failure. We report on a 17-year-old girl with RMND1 related mitochondrial disorder including white matter encephalopathy, hearing loss and renal insufficiency who presented primary ovarian insufficiency in whom a homozygous variant c.713 A > G (p.Asn238Ser) in the RMND1 gene was found. We report the fourth patient with RMND1 biallelic pathogenic variants and primary ovarian insufficiency.

Potassium disorders in pediatric emergency department: Clinical spectrum and management.

INTRODUCTION: Potassium abnormalities are frequent in intensive care but their incidence in the emergency department is unknown. AIM: We describe the spectrum of potassium abnormalities in our tertiary-level pediatric emergency department. METHODS: Retrospective case-control study of all the patients admitted to a single-center tertiary emergency department over a 2.5-year period. We compared patients with hypokalemia (<3.0mEq/L) and patients with hyperkalemia (>6.0mEq/L) against a normal randomized population recruited on a 3:1 ratio with potassium levels between 3.5 and 5mEq/L. RESULTS: Between January 1, 2013 and August 31, 2016 we admitted 108,209 patients to our emergency department. A total of 9342 blood samples were tested and the following potassium measurements were found: 60 cases of hypokalemia (2.8±0.2mEq/L) and 55 cases of hyperkalemia (6.4±0.6mEq/L). In total, 200 patients with normokalemia were recruited (4.1±0.3mEq/L). The main causes of the disorders were non-specific: lower respiratory tract infection (23%) and fracture (15%) for hypokalemia, lower respiratory tract (21.8%) and ear-nose-throat infections (20.0%) for hyperkalemia. Patients with hyperkalemia had an elevated creatinine level (0.72±1.6 vs. 0.40±0.16mg/dL, P<0.0001) with lower bicarbonate (19.4±3.8 vs. 21.8±2.8mmol/L, P=0.0001) and higher phosphorus levels (1.95±0.6 vs. 1.42±0.27mg/dL, P=0.0001). Patients with hypokalemia had an elevated creatinine level (0.66±0.71 vs. 0.40±0.16mg/dL, P<0.0001) and a lower phosphorus level (1.12±0.31 vs. 1.42±0.27mg/dL, P=0.0001). We did not observe significant differences in pH, PCO2, base excess and lactate, or in the mean duration of hospitalization in general wards and pediatric intensive care units according to the PIM and PRISM scores. DISCUSSION: Dyskalemia is rare in emergency department patients: 0.64% for hypokalemia and 0.58% for hyperkalemia. This condition could be explained by a degree of renal failure due to transient volume disturbance. The main mechanism is dehydration due to digestive losses, polypnea in young patients, and poor intake. In the case of hypokalemia, poor intake and digestive losses could be the main explanation. These disorders resolve easily with feeding or perfusion and do not impair development. CONCLUSION: Dyskalemia is rare in emergency department patients and is easily resolved with feeding or perfusion. A plausible etiological mechanism is a transient volume disturbance. Dyskalemia is not predictive of poor development in the emergency pediatric population.

[Nephrogenic syndrome of inappropriate antidiuresis: Early diagnosis avoids severe hyponatremia complications]. / Syndrome néphrogénique d'antidiurèse inappropriée : un diagnostic précoce évite les complications d'une hyponatrémie sévère.

AIM: Nephrogenic syndrome of inappropriate antidiuresis (NSIAD) is a rare disease characterized by a kidney disability to dilute urine and, as a result, severe recurrent hyponatremia. Due to wide variability in clinical expression, the diagnosis still remains a challenge for clinicians. We report our experience of a case in which NSIAD was diagnosed early. We also stress the importance of early diagnosis and treatment, which protects an infant with NSAID from severe hyponatremia. BACKGROUND: A 1-month-old boy was referred to our hospital for persistent hyponatremia and intense vomiting. He was born full term after a normal pregnancy with a normal birth weight. The parents were healthy, nonconsanguineous, of Moroccan origin. They already had healthy twin girls. The physical examination was normal upon admission with no signs of dehydration and normal weight gain since birth. Plasma sodium was very low (125mmol/L) associated with low plasma urea (5mg/dL), osmolality (258 mOsm/kg) and low natriuresis (59mmol/L). These laboratory results suggested inappropriate antidiuretic hormone secretion (SIAD) and the infant was consequently treated with oral urea (he was already receiving sodium supplements that were later stopped). Due to exclusive breastfeeding, water restriction was impossible. Further biological investigation revealed undetectable plasma arginine vasopressin (AVP), suggesting the diagnosis of NSIAD. This was confirmed by genetic sequencing of the AVP receptor (AVPR2), demonstrating the presence of an R137C mutation. CONCLUSIONS: We herein report a case of a genetic fluid balance disorder due to an activating mutation of AVPR2. NSIAD is an X-linked disease, first described in 2005 by Feldman et al., which involved severe recurrent hyponatremia. The very early diagnosis (at 7 weeks of life) and appropriate treatment with urea prevented seizures and cerebral damage due to severe recurrent hyponatremia. Clinicians should consider the diagnosis of NSIAD in infants with recurrent hyponatremia with hemodilution and low AVP serum level. Genetic analysis of the AVPR2 sequence on the X chromosome will confirm the diagnosis and, given the wide variability of clinical expression, sequencing of the family members should be done.

[Practical problems related to the management of febrile urinary tract infection in Vietnamese children]. / Difficultés de prise en charge des infections urinaires fébriles chez l'enfant vietnamien.

BACKGROUND: To describe the practical problems related to urinary tract infection (UTI) management in febrile Vietnamese children. METHODS: During a prospective 28-month inclusion period, 143 febrile children with significant bacteriuria were treated for UTI in the nephrology department of Nhi Dong 2 children's hospital in Ho Chi Minh City, Vietnam. Patients were treated after blood and urine samples had been taken for culture, according to a local antibiotic protocol, parenterally with ceftriaxone 75mg/kg/day. Oral treatment with cefixime 8mg/kg/day was started after 48h of apyrexia for 2 weeks. According to local protocol, antibiotic therapy was only changed if children did not respond clinically to treatment regardless of antibiogram results. RESULTS: Among these 143 children, 51% were girls and 80% of them had their first UTI before the age of 2 years. The commonest causative agent was Escherichia coli (80% of cases) with a high resistance rate to ampicillin (91%) and cotrimoxazole (74%). Extended-spectrum ß-lactamase (ESBL) production was observed in 52% of Enterobacteriaceae isolates. According to antibiotic susceptibility, the initial treatment with ceftriaxone was found to be inappropriate in 63% of cases. CONCLUSIONS: E. coli was responsible for 80% of UTIs in Vietnamese children with a high rate of resistance to first-line antibiotics. ESBL production was found to be extremely high in this study. Based on these data, we propose a new empiric treatment schedule for Vietnamese children suspected of UTI.

[Pediatric nephrology from the fetal kidney to the kidney graft]. / La néphrologie pédiatrique du rein foetal au rein greffé.

The department of pediatric uro-nephrology was created in 1977 in Brugmann hospital. Since then, various sectors have been developed including: hemodialysis and peritoneal dialysis, kidney transplantation, urological and genital surgery, antenatal screening and rapid management of uronephropathies, treatment of voiding dysfunction and neurogenic bladder, management of tubular and glomerular diseases. The progress in genetics, medical imaging, obstetrics, neonatology and surgery has allowed us to take care of our young patients within a multidisciplinary framework. The most original contributions of the department are related to the performance of combined liver-kidney transplantation in primary hyperoxaluria, to the determination of the natural history of several congenital anomalies of the kidney and urinary tract, to the assessment of the role of genetic mutations on tubular and glomerular diseases, to the usefulness of radioisotopic tracers in the measurement of renal function in infants, and to the study of experimental tolerance of allografts. The transition of young renal patients from pediatric to adult care is actually well organized due to our 30 years experience and the excellent collaboration with the adult nephrologists.

Molecular data on vectors and reservoir hosts of zoonotic cutaneous leishmaniasis in central Iran.

Due to the increasing number of positive cases of cutaneous leishmaniasis with occurrence of new foci, a study was carried out to investigate on vectors and reservoirs of the disease in the Shahrood district, central Iran during 2005-2006. Sandflies and rodents were collected using sticky papers and Sherman live traps respectively More than 1700 sandflies were collected and identified, mainly Phlebotomus papatasi species. RAPD-PCR analysis of sandflies showed that 10% of P. papatasi and 4.2% of P. caucasicus were naturally infected with Leishmania major. Two species of rodents, potential reservoirs, Rhombomys opimus (92.5%) and Nesokia indica (7.5%) were trapped in the district. Microscopy identification from rodents confirmed that 91.9% of the Rhombomys opimus were positive to amastigotes. Species identification of isolated parasites revealed Leishmania major DNA in the infected Rhombomys using RAPD-PCR technique. This epidemiological data highlight the importance of the disease in the region and could help people involved in control programs.

Evolution of fetal ultrasonography.

The authors wish to highlight the evolution that has occurred in fetal ultrasound in recent years. A first significant evolution lies in the increasing contribution of first trimester ultrasound for the detection of fetal anomalies. Malformations of several organs and systems have been diagnosed during the first trimester. Furthermore the systematic measurement of the fetal neck translucency has led to increasing rate of detection of aneuploidies and heart malformations. For several years now, three-dimensional (3D) and 4D ultrasound (US) have been used as a complementary tool to 2D US for the evaluation of fetal morphology. This brings an improved morphologic assessment of the fetus. Applications of the techniques are increasing, especially for the fetal face, heart and extremities. The third field where fetal US is continuously providing important information is the knowledge of the natural history of diseases. This has brought significant improvement in the postnatal management of several diseases, especially urinary tract dilatation and broncho-pulmonary malformation.

[The medico-surgical department of uro-nephrology, dialysis and renal transplantation in the Children's Hospital of Brussels]. / Le département médico-chirurgical d'uro-néphrologie, dialyse et transplantation rénale à l'HUDERF.

The department of pediatric uro-nephrology was created in 1977 in Brugmann hospital. Since then, various sectors have been developed including: hemodialysis and peritoneal dialysis, kidney transplantation, urological and genital surgery, antenatal screening and rapid management of uronephropathies, treatment of voiding dysfunction and neurogenic bladder, management of tubular and glomerular diseases. The progress in genetics, medical imaging, obstetrics, neonatology and surgery has allowed us to take care of our young patients within a multidisciplinary framework. The most original contributions of the department are related to the performance of combined liver-kidney transplantation in primary hyperoxaluria, to the determination of the natural history of several congenital anomalies of the kidney and urinary tract, to the assessment of the role of genetical mutations on tubular and glomerular diseases, to the usefulness of radioisotopic tracers in the measurement of renal function in infants, and to the study of experimental tolerization of

Supranormal renal function in unilateral hydronephrosis: does it represent true hyperfunction?

The existence of supranormal differential renal function in unilateral hydronephrosis remains controversial. While some authors consider it as fact, others believe that it is just a technical artifact. Within our department, chromium-51 ethylene diamine tetra-acetic acid (Cr-EDTA) renal clearance is systematically performed in conjunction with technetium-99m mercaptoacetyltriglycine (MAG3) renograms to derive an absolute single kidney glomerular filtration rate (SKGFR). Our data allows us to ascertain whether supranormal differential renal function in unilateral hydronephrosis might be due to hypofunction of the contralateral kidney. Children with marked unilateral hydronephrosis were selected from a large database of MAG3 diuretic(s) renograms. We excluded patients with posterior urethral valves, duplex anomalies, neurogenic bladder, solitary kidney, and those who underwent any previous urological surgery. We also excluded children who had an early furosemide injection (F0 procedure), selecting only those having received furosemide at the end of the renogram (F+20 test). Seventy-three patients (92 renograms) fulfilled these criteria. Differential renal function was calculated using the integral method. Hydronephrotic kidney with a relative uptake > or =55% was defined as supranormal. Six renograms (four patients) demonstrated supranormal relative function on the hydronephrotic side. However, the SKGFR of these kidneys was in all cases within the range of normal values, while the contralateral side demonstrated borderline low SKGFR. Increased relative function on the side of the hydronephrotic kidney is relatively infrequent. When it occurs, it may be related to a borderline hypofunction of the contralateral kidney.

How to interpret a deterioration of split function?

OBJECTIVE: A drop of split renal function often constitutes a criterion for pyeloplasty in hydronephrosis since it is considered as representing deterioration of the affected kidney. The aim of this work was to determine, in a selected population of patients with a drop of split function of at least 5%, if the evolution of single kidney glomerular filtration rate (SKGFR) was parallel to the one of split renal function. METHODS: From a large data basis, we found retrospectively only 29 children (10 below and 19 above two years of age at first examination) having had at least two Tc-99m mertiatide (Tc-99m MAG3) renographic explorations for various urological diseases, with a decrease of split function of at least 5% between the two examinations. Evolution of split function was compared to evolution of SKGFR obtained by means of the combination of Tc-99m MAG3 split function and overall glomerular filtration rate as given by the chromium Cr 51 ethylenediamine tetraacetic acid (EDTA) clearance. RESULTS: For the group above two years of age, SKGFR increased or remained stable in 63% of the cases, while in the children less than 2 years of age, a decrease of SKGFR was never observed, according to the maturation of overall GFR in this age group. Thus, the decrease of split function was not necessarily associated with a similar decrease of SKGFR. CONCLUSION: In patients with unilateral or bilateral urological disorders, deterioration of split renal function does not necessary correspond to a loss of function of the affected kidney. SKGFR often modifies the interpretation of split function.

[Immunosuppressive agents in pediatric renal transplantation]. / Le traitement immunosuppresseur en transplantation renale pédiatrique.

Advances in immunosuppressive therapy over the past decade have led to dramatic improvements of patient and graft survival. The immunosuppression that is used is constantly evolving. The goal remains to find the best combination that will optimize long-term graft survival, while minimizing the adverse effects. It is likely that in the near future the results will even be improved further by the development of new medications with a better therapeutic index and the induction of transplant tolerance.

[Management of isolated fetal dilatations of the kidney pelvis]. / Prise en charge des dilatations pyéliques foetales isolées.

The most common sonographic abnormality found in the fetal urinary tract is collecting system dilatation, accounting for 4.5% of examinations. Numerous renal pelvis measurements and various gestational age cut-off points have been recommended in the assessment of obstructive fetal uropathy. As a result, renal pelvic measurements are not well standardized. The first measurements of the renal pelvis diameter in the 80's suggested that a threshold value of 10 mm was significant in order to distinguish between physiologic and pathologic dilatations. The routine use of prenatal ultrasound and the improving resolution of ultrasound equipment allow the detection of smaller dilatations. The third-trimester threshold value for the antero-posterior renal pelvis diameter of 7 mm is the best ultrasound criterion to predict postnatal renal abnormalities with a positive predictive value of 69%. A renal pelvis dilatation during the second trimester of pregnancy can be used as a warning sign for urinary tract malformation, and should not be ignored even if there is no further progression in the third trimester, because this finding may reveal a significant urologic abnormality in 12% of cases. Isolated pyelectasis can signal the presence of vesico-ureteral reflux. Normal appearing urinary tract on 2 successive neonatal ultrasound rarely coexist with significant abnormal findings on voiding cysto-urethrography. Therefore, in such cases, invasive investigations are not justified.

Early prognostic factors of infants with chronic renal failure caused by renal dysplasia.

Renal dysplasia (RD) is a common cause of chronic renal failure (CRF) in children. The evolution towards end-stage renal failure is unpredictable due to the paucity of early prognostic factors. In order to identify early prognostic clinical criteria, we have retrospectively analyzed renal function and growth in 11 infants with RD and CRF from birth up to 4 years of age. Children with obstructive RD were not included. Glomerular filtration rate (GFR) was estimated from Schwartz formula. In infants with a GFR below 15 ml/min per 1.73 m2 at 6 months of age (group A, n=5), kidney function did not further improve; 4 reached end-stage renal failure between 8 months and 6 years of age. In contrast, infants with a GFR above 15 ml/min per 1.73 m2 at 6 months of age (group B, n=6) experienced a significant improvement in renal function during follow-up, and none required renal replacement therapy. During the first 3 months of life all infants with RD and CRF developed severe growth retardation. Between 6 months and 4 years of age, children from group B grew significantly better than those from group A. In conclusion, our experience suggests that GFR, estimated from Schwartz formula at 6 months of age, is a useful prognostic factor in infants with RD and CRF. Infants with a GFR below 15 ml/min per 1.73 m2 are at risk of severe growth delay and the need for early renal replacement therapy, whereas those with a GFR above 15 ml/min per 1.73 m2 have a relatively favorable long-term prognosis.

[Medulloblastoma: analysis of 14 cases treated at the J. Bordet Institute and literature review]. / Le médulloblastome: analyse de 14 cas traités à l'Institut J. Bordet et revue de la littérature.

Between 1966 and 1986, 14 patients with histologically verified cerebellar medulloblastomas were seen at J. Bordet Institute after total (4 cases) or partial (10 cases) tumor removal. Twelve received postoperative irradiation after some courses of chemotherapy (Vincristine, Procarbazine, Methotrexate) for 5. In 10 cases the X ray treatment was given to the whole cerebrospinal axis with approximately 50 Gy delivered to the primary tumor site, 25-35 Gy to the remaining brain and spinal cord. As in other series of the literature the long term prognosis is not too good, with approximately 50% of the patients surviving more than 5 years. Failure at the primary site happened in 4 cases. As a consequence of the small number of patients treated, no conclusion can be drawn from risk factor analysis. Yet it appears that younger patients fared better than older ones. A detailed description of the side effects of the treatment is therefore given for the five children treated at prepubertal age: some growth impairment seems to be the rule, a consequence of GH deficiency--if not compensated--and of the direct effect of ionizing radiation on the vertebral bodies. While discussing the progress of neurosurgery and radiotherapy for the treatment of medulloblastoma, the authors emphasize the need of more efficient adjuvant chemotherapy regimens and the interest of multicenter trial for evaluating them.