• Childhood Kidney Diseases
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• v.14 no.2
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• pp.120-131
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• 2010

Renal tubular acidosis (RTA) is a metabolic acidosis due to impaired excretion of hydrogen ion, or reabsorption of bicarbonate, or both by the kidney. These renal tubular abnormalities can occur as an inherited disease or can result from other disorders or toxins that affect the renal tubules. Disorders of bicarbonate reclamation by the proximal tubule are classified as proximal RTA, whereas disorders resulting from a primary defect in distal tubular net hydrogen secretion or from a reduced buffer trapping in the tubular lumen are called distal RTA. Hyperkalemic RTA may occur as a result of aldosterone deficiency or tubular insensitivity to its effects. The clinical classification of renal tubular acidosis has been correlated with our current physiological model of how the nephron excretes acid, and this has facilitated genetic studies that have identified mutations in several genes encoding acid and base ion transporters. Growth retardation is a consistent feature of RTA in infants. Identification and correction of acidosis are important in preventing symptoms and guide approved genetic counseling and testing.

• Childhood Kidney Diseases
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• v.24 no.2
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• pp.115-119
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• 2020

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 bed-ridden 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.

• Childhood Kidney Diseases
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• v.8 no.1
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• pp.63-67
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• 2004

A 5-year-old girl was admitted because of an acute onset of weakness in her extremities. She had experienced a similar episode before but had recovered spontaneously. She had previously been diagnosed with distal renal tubular acidosis(RTA) at the age of 2 months. During the period of acute paralysis, her serum potassium level was 1.8 mmol/L and the muscle enzymes were markedly raised suggesting massive rhabdomyolysis. Although hypokalemia is common in renal tubular acidosis, acute paralytic presentation is uncommon and is rarely described in children. We report a case of distal RTA complicated with hypokalemic paralysis with a brief review of related literatures.

• Electrolytes & blood pressure
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• v.16 no.2
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• pp.19-22
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• 2018

Renal Fanconi syndrome (RFS) is caused by generalized proximal tubular dysfunction and can be divided into hereditary and acquired form. Adult-onset RFS is usually associated with drug toxicity or systemic disorders, and modern molecular genetics may explain the etiology of previous idiopathic cases of RFS. Here, we report the case of a 52-year-old woman with RFS whose etiology could not be identified. She presented with features of phosphaturia, renal glucosuria, aminoaciduria, tubular proteinuria, and proximal renal tubular acidosis. Her family history was unremarkable, and previous medications were nonspecific. Her bone mineral density was compatible with osteoporosis, serum intact parathyroid hormone level was mildly elevated, and 25(OH) vitamin D level was insufficient. Her blood urea nitrogen and serum creatinine levels were 8.4 and 1.19 mg/dL, respectively (estimated glomerular filtration rate, $53mL/min/1.73m^2$). Percutaneous renal biopsy was performed but revealed no specific renal pathology, including mitochondrial morphology. No mutation was detected in EHHADH gene. We propose the possibility of involvement of other genes or molecules in this case of adult RFS.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.1
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• pp.41-46
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• 2002

Effect of cadmium (Cd) intoxication on renal acid-base regulation was studied in adult male Sprague-Dawley rats. Cd intoxication was induced by subcutaneous injections of $CdCl_2$ at a dose of 2 mg Cd/kg/day for $3{\sim}4$ weeks. In Cd-intoxicated animals, arterial pH, $PCO_2$ and plasma bicarbonate concentration decreased, showing a metabolic acidosis. Urine pH and urinary bicarbonate excretion increased and titratable acid excretion decreased with no change in ammonium excretion. In renal cortical brush-border membrane vesicles derived from Cd-exposed animals, the $Na^+/H^+$ antiporter activity was significantly attenuated. These results indicate that chronic exposures to Cd impair the proximal tubular mechanism for $H^+$ secretion (i.e., $Na^+/H^+$ antiport), leading to a metabolic acidosis.

• Journal of The Korean Dental Society of Anesthesiology
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• v.2 no.1 s.2
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• pp.33-37
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• 2002

The oculo-cerebro-renal syndrome of Lowe (Lowe syndrome) is an X-linked recessive disorder involving the eyes, nervous systems, and kidneys. The clinical manifestation of this syndrome is characterized by congenital cataracts, glaucoma, seizure disorder, psychomotor growth retardation, hypotonia, renal tubular acidosis, aminoaciduria, rickets, and osteoporosis. We report a 5-year old boy underwent general anesthesia for the treatment of multiple dental carries. During intraoperative period, marked metabolic acidosis was noted and such acidosis was partially corrected by hyperventilation. We suggest that patients with Lowe's syndrome should be attention and treated to possible anesthetic hazards such as metabolic acidosis due to renal tubular dysfunction, rise of intraocular pressure in patient with glaucoma, the fragility of the bone structures due to rickets and osteoporosis.

• Childhood Kidney Diseases
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• v.16 no.2
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• pp.126-131
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• 2012

Sj$\ddot{o}$gren's syndrome (SS) is an autoimmune disorder primarily affecting the salivary and lacrimal glands. In addition, extra-glandular manifestations involving the lungs, liver, kidneys, pancreas, skin and central nervous system were reported in patients with SS. These extra-glandular manifestations are not rare in adult patient, but are very rare in pediatric SS. Renal manifestations are relatively common in adult SS, but are rarely reported in childhood SS. We experienced a girl with primary SS manifested with nephrogenic diabetes insipidus and renal tubular acidosis.

• Journal of Veterinary Clinics
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• v.22 no.4
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• pp.420-423
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• 2005

A 2-year-old 16-kg, intact female lindo was presented with weight loss and poor hair coat. Abnormal serum biochemical values included mild hypokalemia (3.9 mmol/L, reference range 4.37 to 5.35 mmol/L) and mild hyperglycemia (124 mg/dl, reference range 65 to 118 mg/dl). in the complete blood count and diagnostic imaging examination, abnormal changes wer not seen. The analysis of urine sample obtained from cystocentesis revealed glucosuria (> 100 mg/dl) and mild proteinuria. Repeated analysis after admission showed persistent glucosuria and hypokalemia. But blood glucose values did not exceed the renal threshold fur glucose reabsorption. To differentiate cause of the glucosuria, the glucose tolerance test and the low-dosage dexamethasone suppression test were indicated. Results of both tests were normal. In addition, the serum total thyroxine $(T_4)$ value was within normal range. The arterial blood gas analysis showed no remarkable changes. The fractional reabsorption rates of amino acids and phosphorus were calculated above $97\%$. Based on these findings, the dog was diagnosed as renal glucosuria due to proximal renal tubular dysfunction. But this persistent renal glucosuria with hypokalemia may be the initial sign of Fanconi's syndrome or proximal renal tubular acidosis.

• Clinical and Experimental Pediatrics
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• v.46 no.8
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• pp.826-830
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• 2003

ARCI syndrome consists of arthrogryposis, renal tubular acidosis, cholestatic jaundice and icthyosis. We experienced an ARCI syndrome case with corpus callosum hypoplasia and atrial septal defect. This case had oral feeding difficulty, multiple joint contracture, renal tubular acidosis and neurogenic muscular atrophy at neonatal period. At two months of age, icthyosis and cholestatic jaundice were diagnosed. The case was hospitalized due to pneumonia at four months of age. Corpus callosum hypoplasia and atrial septal defect were detected. The case was treated with a mechanical ventilator because pneumonia was aggravated and respiratory failure occurred. The patient expired at five months of age.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.1
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• pp.69-76
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• 1998

Cis-diamminedichloroplatinum II (cisplatin), an effective antitumor agent, induces acute renal failure by unknown mechanisms. To investigate direct toxic effects of cisplatin in the renal proximal tubular transport system, OK cell line was selected as a cell model and $Na^+/H^+$ antiport activity was evaluated during a course of cisplatin treatment. The cells grown to confluence were treated with cisplatin for 1 hour, washed, and incubated for up to 48 hours. At appropriate intervals, cells were examined for $Na^+/H^+$ antiport activity by measuring the recovery of intracellular pH (pHi) after acid loading. Cisplatin of less than 50 ${\mu}M$ induced no significant changes in cell viability in 24 hours, but it decreased the viability markedly after 48 hours. In cells exposed to 50 ${\mu}M$ cisplatin for 24 hours, the $Na^+-dependent$ pHi recovery (i.e., $Na^+/H^+$ antiport) was drastically inhibited with no changes in the $Na^+-independent$ recovery. Kinetic analysis of the $Na^+-dependent$ pHi recovery indicated that the Vmax was reduced, but the apparent Km was not altered. The cellular $Na^+$ and $K^+$ contents determined immediately before the transport measurement appeared to be similar in the control and cisplatin group, thus, the driving force for $Na^+-coupled$ transport was not different. These results indicate that cisplatin exposure impairs the $Na^+/H^+$ antiport capacity in OK cells. It is, therefore, possible that in patients treated with a high dose of cisplatin, proximal tubular mechanism for proton secretion (hence $HCO_3^-$ reabsorption) could be attenuated, leading to a metabolic acidosis (proximal renal tubular acidosis).