Acute renal failure with severe loin pain and patch renal ischemia after anaerobic exercise (ALPE) is a rare cause of exercise-induced acute kidney injury. Some ALPE patients also have renal hypouricemia. Mutations in the SCL22A12 gene are among the major factors of hypouricemia. Education for the prevention of relapse and genetic counseling should be recommended to ALPE patients with renal hypouricemia. This paper reports a 25-year-old man who showed recurrent exercise-induced ARF and renal hypouricemia with R90H mutation in his SCL22A12 gene.
Acute Kidney Injury ; Genetic Counseling ; Humans ; Ischemia ; Recurrence ; Renal Tubular Transport, Inborn Errors ; Urinary Calculi

Chronic hypophosphatemia caused by decreased intestinal absorption or increased renal clearance, may lead to rickets or osteomalacia independently of other predisposing abnormalities. The conditions commonly associated with increased renal clearance of phosphate are X-linked hypophosphatemic rickets, tumor associated rickets/osteomalacia, RTA and Fanconi syndrome. Recently we experienced 3 men with adult-onset, histologically proven osteomalacia associated with increased renal clearance of phosphate. None of them had a family history of bone disease, tumors or other tubular defects. All of these had remarkable biochemical and clinical improvement with medical treatment such as 1, 25-dihydroxyvitamin D and phosphate supplementation. Although we did not find tumors yet, we could not rule out the possibility of tumor-associated osteomalcia since it often takes several years to make a diagnosis because of small size, benign nature and unusual location of tumors. Thus, careful long-term follow up for tumor occurrence will be maintained in these patients with sporadic nonfamilial hypophosphatemic osteomalacia.
Bone Diseases ; Diagnosis ; Familial Hypophosphatemic Rickets ; Fanconi Syndrome ; Follow-Up Studies ; Humans ; Hypophosphatemia ; Intestinal Absorption ; Male ; Osteomalacia ; Rickets

Magnesium is the second most common intracellular divalent cation. Magnesium balance in the body is controlled by a dynamic interplay among intestinal absorption, exchange with bone, and renal excretion. Intestinal magnesium absorption proceeds in both a passive paracellular and an active transcellular manner. Regulation of serum magnesium concentrations is achieved mainly by control of renal magnesium reabsorption. Only 20% of filtered magnesium is reabsorbed in the proximal tubule, whereas 60% is reclaimed in the cortical thick ascending limb (TAL) and another 5-10% in the distal convoluted tubule (DCT). The passive paracellular transport of magnesium in the TAL is closely related with the mutations in claudin-16/paracellin-1 and is responsible for familial hypomagnesemia with hypercalciuria and nephrocalcinosis. The active transcellular transport of magnesium in the DCT was similarly enhanced by the realization that defects in transient receptor potential melastatin 6 (TRPM6) cause hypomagnesemia with secondary hypocalcemia. This channel regulates the apical entry of magnesium into epithelia and alters whole-body magnesium homeostasis by controlling urinary excretion. TRPM6 is regulated at the transcriptional level by acid-base status, 17beta-estradiol, and both FK506 and cyclosporine. The molecular identity of the protein responsible for the basolateral exit of magnesium from the epithelial cell remains unidentified.
Absorption ; Cyclosporine ; Epithelial Cells ; Extremities ; Homeostasis ; Hypercalciuria ; Hypocalcemia ; Intestinal Absorption ; Magnesium ; Nephrocalcinosis ; Renal Tubular Transport, Inborn Errors ; Tacrolimus ; Transcytosis ; Transient Receptor Potential Channels

BACKGROUND: Acute renal failure (ARF) with severe loin pain and patchy renal vasoconstriction (PRV) is a syndrome presenting with sudden loin pain after anaerobic exercise. We aimed to investigate the clinical characteristics and the efficacy of diagnostic imaging studies of patients with this syndrome. METHODS: We retrospectively selected 17 patients with ARF accompanied by loin or abdominal pain who showed multiple patchy wedge-shaped delayed contrast enhancements on a computerized tomography scan. Information about the clinical characteristics, including the nature of pain and combined symptoms, suspected causes, such as exercise, drug or alcohol intake, and renal hypouricemia, and the results of laboratory and imaging tests were gathered. RESULTS: The mean age of patients with episodes of ARF accompanied by loin pain was 23.0+/-6.5 (range 16-35) years old. Pain was mainly located in the loin (70.6%) or abdominal area (76.5%) and continued for approximately 3.5+/-4.0 days. Exercise was suspected as a primary cause of disease in 12 (70.6%) patients. Maximal serum creatinine was 5.42+/-3.16 (1.4-12.1) mg/dL 3.1+/-1.8 (1-7) days after the onset of pain. The peak level of serum uric acid was 9.41+/-2.91 (6.0-15.8) mg/dL. All of the patients recovered to near-normal renal function, and one patient showed hypouricemia after recovery. CONCLUSION: ARF with severe loin pain and PRV can present with loin or abdominal pain, even without a history of anaerobic exercise. Careful history taking and appropriate imaging studies are critical in the diagnosis and management of this syndrome.
Abdominal Pain ; Acute Kidney Injury ; Creatinine ; Diagnostic Imaging ; Humans ; Renal Tubular Transport, Inborn Errors ; Retrospective Studies ; Uric Acid ; Urinary Calculi ; Vasoconstriction

Acute renal failure with severe loin pain which develops after anaerobic exercise is rare. One of predisposing factors of exercise-induced acute renal failure is renal hypouricemia. Idiopathic renal hypouricemia is a genetic disorder characterized by hypouricemia with abnormally high renal tubular uric acid excretion. The mutation in SCL22A12 gene which encodes renal uric acid transporter, URAT1, is the known major cause of this disorder. We here described a 25-yr-old man showing idiopathic renal hypouricemia with G774A mutation in SCL22A12 who presented exercise-induced acute renal failure. There have been a few reports of mutational analysis in Korean idiopathic renal hypouricemia without acute renal failure. This is the first report of genetically diagnosed idiopathic renal hypouricemia with exercise-induced acute renal failure in Korea.
Acute Kidney Injury/*diagnosis/genetics ; Adult ; Amino Acid Substitution ; DNA Mutational Analysis ; Exercise ; Exons ; Humans ; Male ; Mutation ; Organic Anion Transporters/*genetics ; Organic Cation Transport Proteins/*genetics ; Renal Tubular Transport, Inborn Errors/etiology/*genetics ; Urinary Calculi/etiology/*genetics

Fanconi syndrome is a complex of renal tubular dysfunction defined by glycosuria without diabetes, generalized aminoaciduria, phosphaturia, bicarbonaturia, uric aciduria, and renal tubular acidosis. It is often associated with hypokalemia, hypophosphatemia, rickets and osteomalacia. We have experienced one case of Fanconi syndrome with chronic tubulointerstitial nephritis. The patient was a 4 year old and his chief complaints were polyuria, polydipsia, and poor weight gain. There were hyperchloremic metabolic acidosis, hypokalemia, glycosuria, generalized aminoaciduria and phosphaturia. We report a case of Fanconi syndrome with brief review of the literatures.
Acidosis ; Acidosis, Renal Tubular ; Child, Preschool ; Fanconi Syndrome* ; Glycosuria ; Humans ; Hypokalemia ; Hypophosphatemia ; Hypophosphatemia, Familial ; Nephritis, Interstitial ; Osteomalacia ; Polydipsia ; Polyuria ; Rickets ; Weight Gain

Tubulointerstitial nephritis and uveitis (TINU) syndrome is a rare disease that comprises 4.7% of acute interstitial nephritis. With reno-ocular manifestations, TINU syndrome is accompanied by symptoms such as fever, fatigue, malaise, anorexia, vomiting, and arthralgia. TINU syndrome is reported mainly in children or adolescent girls, and it is rare in adults. Although TINU syndrome can present with multiple renal tubular defects, Fanconi syndrome characterized by generalized impairment of proximal tubular function, leading to renal glucosuria, hyperuricosuria, hyperphosphaturia, proximal renal tubular acidosis, and kaliuresis leading to hypokalemia, has rarely been described. We report a case of TINU syndrome with Fanconi syndrome in a 46-year-old HLA B27-positive Korean woman.
Acidosis, Renal Tubular ; Adolescent ; Adult ; Anorexia ; Arthralgia ; Child ; Fanconi Syndrome* ; Fatigue ; Female ; Fever ; Glycosuria, Renal ; Humans ; Hypokalemia ; Hypophosphatemia, Familial ; Middle Aged ; Nephritis, Interstitial* ; Rare Diseases ; Uveitis* ; Vomiting

PURPOSE: Hypophosphatemic rickets is a hereditary disease, characterized by hypophosphatemia due to renal phosphate wasting, impaired renal production of 1,25-dihydroxyvitamin D3, rachitic bone deformities and impaired growth. The purpose of this study is to provide clinical profiles of patients with hypophosphatemic rickets in our hospital. METHODS: Between July 1983 and February 2004, 56 patients were diagnosed as having hypophosphatemic rickets. The medical records of these patients were reviewed retrospectively. Clinical manifestations, family histories, laboratory data, treatment outcomes were described. RESULTS: Fifty six patients were enrolled in this study. The average age at symptom onset and diagnosis were 20 months and 5 years respectively. Fourteen patients had family histories. The main clinical manifestations were bow legs and short stature. There was a significant negative correlation between the ages and the height z-scores at the time of diagnosis(r=-0.47, P=0.005). Initial laboratory data showed normocalcemia, hypophosphatemia, elevated serum alkaline phosphatase, decreased tubular reabsorption of phosphate and a normal range of 1,25-dihydroxyvitamin D3. Radiographic examinations of bone revealed fraying, widening and cupping of the metaphyseal ends. Treatment consisted of Joulie solution and vitamin D metabolites, and resulted in improved biochemical and radiographic findings. However, height z-scores remained essentially unchanged(P=0.224). Complications of treatment were frequently observed, including hyperparathyroidism, nephrocalcinosis, and hypercalciuria. Sixteen patients had corrective osteotomy and 4 of them underwent leg lengthening together. CONCLUSION: There was a gap of several years between the onset of symptoms and the diagnosis. Early treatment seems to be essential to growth. For the earlier treatment, the offsprings of affected parents should be followed up closely.
Alkaline Phosphatase ; Calcitriol ; Congenital Abnormalities ; Diagnosis ; Familial Hypophosphatemic Rickets ; Genetic Diseases, Inborn ; Genu Varum ; Humans ; Hypercalciuria ; Hyperparathyroidism ; Hypophosphatemia ; Hypophosphatemia, Familial ; Leg ; Medical Records ; Nephrocalcinosis ; Osteotomy ; Parents ; Reference Values ; Retrospective Studies ; Rickets, Hypophosphatemic* ; Vitamin D

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, 53 mL/min/1.73 m²). 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.
Acidosis, Renal Tubular ; Adult ; Biopsy ; Blood Urea Nitrogen ; Bone Density ; Creatinine ; Drug-Related Side Effects and Adverse Reactions ; Fanconi Syndrome ; Female ; Glomerular Filtration Rate ; Glycosuria, Renal ; Humans ; Hypophosphatemia, Familial ; Middle Aged ; Molecular Biology ; Osteoporosis ; Parathyroid Hormone ; Pathology ; Proteinuria ; Vitamin D

X-linked hypophosphatemia (XLH) is a hereditary metabolic disease caused by the loss of phosphate through the renal tubules into the urine, and an associated decrease in serum calcium and potassium phosphate. Its dental features include spontaneous dental abscesses that occur in the absence of trauma or dental caries. The aim of this case report was to describe the dental problems of XLH patients and to evaluate limitations in their treatment. A 14 year old male and a 38 year old female with XLH were referred to the Department of Conservative Dentistry for endodontic treatment. The dental findings were periapical abscesses without obvious trauma or caries. Conservative endodontic treatment was performed in teeth with pulp necrosis and abscess. In case 1, the treated teeth showed improvements in bone healing, without clinical symptoms. However, in case 2, the implants and the treated tooth showed hypermobility, and the final restoration was therefore postponed. Early diagnosis, periodic examinations, and communication with the patient's pediatrician are important in the dental management of patients with XLH.
Abscess ; Calcium ; Dental Caries ; Dental Pulp Necrosis ; Dentistry ; Early Diagnosis ; Familial Hypophosphatemic Rickets* ; Female ; Humans ; Hypophosphatemia ; Male ; Metabolic Diseases ; Periapical Abscess ; Potassium ; Tooth