Current Understanding of Nephrotic Syndrome in Children.

Nephrotic syndrome in children is mostly idiopathic in origin. About 90% of patients respond to corticosteroids; 80-90% have at least one relapse and 3-10% become corticosteroid resistant after the initial response. A kidney biopsy is seldom indicated for diagnosis except in patients with atypical presentation or corticosteroid resistance.

Kidney and Metabolic Phenotypes in Glycogen Storage Disease Type-I Patients.

A retrospective chart review of 32 GSD- I patients, followed at the American University of Beirut Medical Center, between 2007 and 2018 was conducted. Diagnosis was confirmed by enzymatic and/or genetic studies. Clinical presentation, growth, and kidney outcome were assessed.

Norovirus: a novel etiologic agent in hemolytic uremic syndrome in an infant.

Background: Hemolytic uremic syndrome is a rare thrombotic microangiopathy usually seen in infants and children below the age of 5 years. It usually follows a bout of bloody diarrhea caused by Shiga toxin producing E coli and is characterized by microangiopathic hemolytic anemia, thrombocytopenia and acute kidney injury. We report the first case of hemolytic uremic syndrome in an infant following Norovirus gastroenteritis.

Distinctive vasculopathy with systemic involvement due to levamisole long-term therapy: a case report.

Background: Levamisole belongs to the antihelminthic class of drugs that are sometimes administered to patients with frequently relapsing or steroid-dependent nephrotic syndrome, owing to its steroid-sparing effects. Neutropenia and skin lesions, compatible with vasculitis, have been reported as drug complications, but they are rarely associated with any systemic involvement.

Case Presentation: We report a case of a 9-year-old Arab boy with steroid-dependent nephrotic syndrome who was treated with levamisole after his third relapse.

Pamidronate Rescue Therapy for Hypercalcemia in a Child With Williams Syndrome.

A 15-month-old male infant diagnosed with Williams Syndrome (WS) was admitted with severe hypercalcemia and nephrocalcinosis. Intravenous hydration and furosemide failed to yield an appreciable and sustainable fall in serum calcium, while the injection of pamidronate achieved a significant decrease in serum calcium in a short period of time. This bisphosphonate could be considered as a second-line treatment for refractory hypercalcemia in WS.

Tooth Development Associated with Mutations in Hereditary Vitamin D-Resistant Rickets.

Hereditary vitamin D-resistant rickets (HVDRR) is a rare genetic disorder caused by mutations at the level of the vitamin D receptor ( VDR) gene. The disease is characterized by refractory hypocalcemia, elevated serum levels of 1,25-dihydroxy-vitamin D, retarded growth, sparse body hair (sometimes alopecia), premature tooth loss, enlarged pulp chambers, thin dentine, and hypoplastic enamel. The aims of this study were 1) to document the dental development of children with HVDRR in association with the mutation type within the VDR and 2) to evaluate the association between dental development and the timing of and response to HVDRR treatment.

Ureteropelvic Junction Obstruction and Parathyroid Adenoma: Coincidence or Link?

Congenital ureteropelvic junction obstruction (UPJO) is the most common cause of upper urinary tract obstruction in children. It is generally diagnosed in the routine work-up during antenatal period and is characterized by spontaneous recovery. It can be associated with urolithiasis; hence further investigation should be carried out.

Hereditary vitamin D-resistant rickets in Lebanese patients: the p.R391S and p.H397P variants have different phenotypes.

Background: Hereditary vitamin D-resistant rickets (HVDRR) is an autosomal recessive disorder caused by mutations in the vitamin D receptor (VDR) gene. Variable phenotypes have been associated with these mutations, and some of these were linked to the effects they have on the interacting partners of VDR, mainly the retinoic X receptor (RXR).

Methods: We examined four patients with HVDRR from three unrelated Lebanese families.

Severe hypoalphalipoproteinaemia in a child with acute post-streptococcal glomerulonephritis (APSGN).

We describe a child with acute post-streptococcal glomerulonephritis (APSGN), who developed a very low plasma high-density lipoprotein cholesterol (α-lipoprotein) in association with transient but massive proteinuria. The hypoalphalipoproteinaemia resolved spontaneously concomitant with the remission in proteinuria and the patient had a complete clinical recovery. Urinary loss of apolipoprotein A1 may have contributed to the hypoalphalipoproteinaemia.

Mutations in kelch-like 3 and cullin 3 cause hypertension and electrolyte abnormalities.

Hypertension affects one billion people and is a principal reversible risk factor for cardiovascular disease. Pseudohypoaldosteronism type II (PHAII), a rare Mendelian syndrome featuring hypertension, hyperkalaemia and metabolic acidosis, has revealed previously unrecognized physiology orchestrating the balance between renal salt reabsorption and K(+) and H(+) excretion. Here we used exome sequencing to identify mutations in kelch-like 3 (KLHL3) or cullin 3 (CUL3) in PHAII patients from 41 unrelated families.

Etiology of hypertension in children and adolescents.

While most hypertension in children has been previously considered secondary to renal, cardiovascular or endocrine etiology, a substantial number of children aged 6 to 20 years are now diagnosed with primary or essential hypertension. Hypertension in children and adolescents seems to be increasing over the past two decades. This is attributed at least in part to an increased prevalence of overweight in this population.

Genetic diagnosis by whole exome capture and massively parallel DNA sequencing.

Protein coding genes constitute only approximately 1% of the human genome but harbor 85% of the mutations with large effects on disease-related traits. Therefore, efficient strategies for selectively sequencing complete coding regions (i.e.

Renal venous thrombosis in a newborn with prothrombotic risk factors.

Renal venous thrombosis (RVT) is a rare but a well recognized entity in children and neonates. The clinical signs of neonatal RVT include hypertension, enlarged kidney(s), hematuria, renal insufficiency, proteinuria, thrombocytopenia, or all. Persisting impairment of kidney function and hypertension are serious and common complications in patients with RVT.

Primary hyperoxaluria type 1: An underestimated cause of nephrocalcinosis and chronic renal failure in Saudi Arabian children.

Background: Primary hyperoxaluria type I (PHI) is a rare metabolic disease caused by deficiency or abnormalities of the peroxisomal enzyme alanine-glyoxylate aminotransferase. In the majority of patients, the clinical expression of PHI is characterized by recurrent calcium oxalate urolithiasis, nephrocalcinosis and renal failure.

Patients And Methods: Sixteen children aged 5 months to 14 years were diagnosed as PHI over a 10-year period ending in June 1997.

A novel PCLN-1 gene mutation in familial hypomagnesemia with hypercalciuria and atypical phenotype.

Familial hypomagnesemic hypercalciuria and nephrocalcinosis (FHHNC [MIM 248250]) is a rare renal tubular disorder characterized by impaired reabsorption of magnesium and calcium in the thick ascending limb of Henle's loop (tALH), causing renal magnesium wasting and hypercalciuria. Patients with FHHNC usually present with recurrent urinary tract infections, polyuria, nephrolithiasis (NL) and nephrocalcinosis (NC) with many progressing to chronic renal failure (CRF). We have shown recently that loss of function mutations in paracellin-1 PCLN-1/claudin-16, a renal tight junction protein located in the TAL, are causative of FHHNC.

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

Autosomal recessive distal renal tubular acidosis (rdRTA) is characterised by severe hyperchloraemic metabolic acidosis in childhood, hypokalaemia, decreased urinary calcium solubility, and impaired bone physiology and growth. Two types of rdRTA have been differentiated by the presence or absence of sensorineural hearing loss, but appear otherwise clinically similar. Recently, we identified mutations in genes encoding two different subunits of the renal alpha-intercalated cell's apical H(+)-ATPase that cause rdRTA.