Renal tubular acidosis in childhood (original) (raw)

Incomplete distal renal tubular acidosis affects growth in children

Nephrology Dialysis Transplantation, 2007

Background. Incomplete distal renal tubular acidosis (idRTA) is recognized as an underlying aetiology in recurrent nephrolithiasis. Until the recently reported high prevalence of idRTA in adults with osteoporosis, the effect of idRTA on skeletal parameters was not known. We hypothesize that idRTA has a potential to affect height in the paediatric population. Methods. In a cross-sectional study, the children with posterior urethral valves (PUV), with normal estimated glomerular filtration rates, were evaluated for idRTA and complete dRTA. The idRTA evaluation was done by short ammonium chloride acidification test. The height standard deviation scores (SDS) in the idRTA group were compared with PUV children without dRTA, with complete dRTA, and to age and gender matched controls with no renal issue (n ¼ 50). Results. The idRTA group (n ¼ 17) manifested a significantly lower mean height SDS (À1.94 AE 0.41 vs À0.46 AE 0.28; P < 0.001) and a higher short stature prevalence (height SDS below 2) (18% vs 0; P ¼ 0.06) as compared with those without dRTA (n ¼ 23). The matched controls showed a significantly higher height SDS as compared with the idRTA group (À0.39 AE 0.25 vs À1.94 AE 0.41; P < 0.001). As compared with the complete dRTA group (n ¼ 9), the children with idRTA did have significantly higher height SDS (À1.94 AE 0.41 vs À5.31 AE 1.95; P ¼ 0.002), and a lower short stature prevalence (18% vs 78%; P ¼ 0.001). On multivariate analysis, dRTA was significantly associated with the height SDS ( ¼ À0.88; P < 0.001).

Distal Renal Tubular Acidosis in Adolescence with Severe Growth Retardation and Nephrocalcinosis

Journal of Nepal Medical Association

Chronic acidosis is an important, often overlooked cause of growth retardation. Here we present the case of a girl with distal renal tubular acidosis who had visited multiple hospitals before the diagnosis was made. She presented to us in adolescence with non anion gap metabolic acidosis, hypokalemia, severe growth retardation and nephrocalcinosis. In 18 months follow up with alkali therapy, she had good weight gain and growth velocity. Keywords: growth retardation; hypokalemia; nephrocalcinosis; renal tubular acidosis.

A Pediatric Case of Long-term Untreated Distal Renal Tubular Acidosis

Childhood Kidney Diseases

Distal renal tubular acidosis (dRTA) is a rare renal tubular disorder characterized by normal anion gap metabolic acidosis, hypokalemia, and high urine pH. It can be inherited or acquired. In untreated pediatric patients with dRTA, rickets and growth retardation are common. We report the case of a 12-year-old Lao girl who presented with typical clinical features of dRTA with severe bone deformities that developed after a bedridden state due to a bicycle accident at the age of 8 years. Initial laboratory tests revealed metabolic acidosis with a normal anion gap, hypokalemia, and alkali urine. Renal ultrasonography revealed bilateral medullary nephrocalcinosis. Whole exome sequencing revealed no pathogenic mutations. After treatment with oral alkali, potassium, and vitamin D, she could walk and run. Later, she underwent corrective orthopedic surgeries for bony deformities. Thus, in pediatric dRTA patients, despite severe symptoms remaining untreated, accurate diagnosis and proper management can improve quality of life.

Incomplete distal renal tubular acidosis in children

Acta Paediatrica, 2020

AimTo describe incomplete distal renal tubular acidosis (iDRTA) in paediatric patients, a term used for the diagnosis of patients who do not develop spontaneous overt metabolic acidosis but are unable to acidify the urine in response to an ammonium chloride load.MethodsTests used to explore urinary acidification were revised. In addition, publications in English extracted from 161 entries yielded by a PubMed database search, using ‘incomplete distal renal tubular acidosis’ as keyword, were reviewed.ResultsIncomplete distal renal tubular acidosis has mostly been identified in adults with autoimmune diseases, nephrolithiasis, nephrocalcinosis and/or osteopenia. iDRTA has been reported in few paediatric patients with rickets, congenital abnormalities of kidney and urological tract and/or growth failure. The pathophysiological mechanisms potentially responsible for the defect of urinary acidification are discussed as well as the clinical and biochemical findings of iDRTA described in ch...

Long-term outcome in children with primary distal renal tubular acidosis

Indian pediatrics, 2005

To evaluate complications in adequately treated children with distal renal tubular acidosis (RTA) and to identify factors influencing their development. Records of patients with primary distal RTA followed for 2 or more years at this hospital were reviewed. Case records were examined for age at onset of symptoms and at initiation of treatment, treatment details, follow-up and complications. Height, weight and growth velocity were expressed as standard deviation score (SDS) during different periods of follow-up. Regression analysis was performed to evaluate factors influencing increase in height and weight SDS. P value of less than 0.05 was considered significant. Of 18 patients (eleven boys), the diagnosis was established at the median (range) age of 6 yr (1.5-13 yr). These patients were followed up for a median (range) period of 4 yr (2-18.5 yr). Short stature (height SDS <-2) was noted in all patients at the time of diagnosis with median (range) height SDS of -5.2(-7.5 - -0.4)....

Atypical presentation of distal renal tubular acidosis in two siblings

Pediatric Nephrology, 2008

Primary distal renal tubular acidosis (dRTA) is an inherited disease characterized by the inability of the distal tubule to lower urine pH <5.50 during systemic acidosis. We report two male siblings who presented with severe hyperchloremic metabolic acidosis, high urinary pH, nephrocalcinosis, growth retardation, sensorineural hearing loss, and hypokalemic paralysis. Laboratory investigations revealed proximal tubular dysfunction (low molecular weight proteinuria, generalized hyperaminoaciduria, hypophosphatemia with hyperphosphaturia, and hypouricemia with hyperuricosuria). There was significant hyperoxaluria and laboratory evidence for mild rhabdomyolysis. Under potassium and alkali therapy, proximal tubular abnormalities, muscular enzymes, and oxaluria normalized. A homozygous mutation in the ATP6V1B1 gene, which is responsible for dRTA with early hearing loss, was detected in both siblings. In conclusion, proximal tubular dysfunction and hyperoxaluria may be found in children with dRTA and are reversible under appropriate therapy.

Genotype-Phenotype Analysis in Pediatric Patients with Distal Renal Tubular Acidosis

Kidney & blood pressure research, 2018

Primary distal renal tubular acidosis (dRTA) in children is a rare genetic disorder, and three causative mutated genes have been identified: SLC4A1, ATP6V1B1, and ATP6V0A4. We analyzed the prevalence and phenotypic differences of genetic mutations in children with dRTA. A total of 17 children with dRTA were enrolled in the study. All patients underwent genetic testing for all three candidate genes. Pathogenic mutations, including six novel mutations, were detected in 15 (88.2%) patients: dominant SLC4A1 mutations in ten (58.8%) patients, recessive ATP6V0A4 mutations in three (17.6%) patients, and recessive ATP6V1B1 mutations in two (11.8%) patients. Compared to other patients, patients with SLC4A1 mutations showed an older age of onset (3.7 ± 2.6 years) and less severe metabolic acidosis at initial presentation. All patients developed nephrocalcinosis, and sensorineural hearing loss was observed in two patients with ATP6V1B1 mutations. Three (17.6%) patients had decreased renal func...

Natural history of primary distal renal tubular acidosis treated since infancy

Journal of Pediatrics, 1982

Clinical and pathophysiologic studies were performed in five unrelated children with primary distal renal tubular acidosis who were diagnosed during infancy and followed for 3 to 9 89 years. All patients had permanent defects in hydrogen ion secretion, sodium reabsorption, and concentrating capacity. A transient, age-related, proximal tubular defect in sodium and bicarbonate reabsorption was also present. Renal bicarbonate wasting was mainly observed during the first years of life and progressively decreased with advancing age. Glomerular filtration rate remained within normal limits. Following sustained therapy with sodium and potassium bicarbonate, the patients had optimal growth, arrest of progression of nephrocalcinosis, and lack of other characteristic features of the disease with the exception of polyuria. Dosage of alkali was mainly determined by the magnitude of the renal bicarbonate loss and decreased progressively from a maximum of 3.9 to 10.0 mEq/kg/day during the first year of life to about 3 mEq/kg/day at or beyond 6 years of age. The total dosage of alkali required could be derived by the sum of the urinary excretion of bicarbonate plus 2 mEq/kg/day, which represents mean endogenous acid production. Although caleiuria was normal when metabolic acidosis was corrected, patients with higher urinary sodium excretion had higher urinary excretion of calcium and thus were at greater risk of developing nephrocalcinosis if therapy was not carefully controlled.

Renal tubular acidosis in infants and children

The Journal of Pediatrics, 1972

... Edelmann, CM, Jr., Barnett, HL, Stark, H., Boichis, H., and Rodriguez-Soriano, J.: Astandardized test of renal concentrating capacity in children ... Seldin, DW, and Wilson, JD: Renal tubular acidosis, in Stanbury, JB, Wyngaar-den, JB, and Fredrlckson, DS, editors: The metabolic ...

Low Molecular Weight Proteinuria in Children with Distal Renal Tubular Acidosis

PRILOZI, 2018

Distal renal tubular acidosis (dRTA) (MIM #267300, #602722 and #179800) is a rare inherited tubulopathy characterized by the inability of the distal tubule to acidify the urine with consecutive systemic acidosis. The clinical features include polyuria, polydipsia, poor appetite, failure to thrive, short stature and rickets. Prominent biochemical features are hypokalemia, hypercalciuria and hypocitraturia. There are reports on patients who presented with unusual biochemical features such as low molecular proteinuria, hypophosphatemia, hypouricemia, generalized hyperaminioaciduria, hyperoxaluria and other making diagnostic confusion to the clinicians. In this work, we report on a series of 8 children with clinically, biochemically and genetically proven dRTA who present with low molecular proteinuria at the disease onset. With metabolic compensation of the disease, there was complete resolution of the low molecular weight protenuria and other proximal tubular abnormalities in all chil...