Renal Tubular Defect Research Articles

Biochemical Markers of Early Renal Dysfunction in Patients with β-thalassemia Major: A Systematic Review and Meta-analysis.

Early diagnosis of renal dysfunction in β-thalassemia major (β- TM) may help take specific measures to delay irreversible damage and renal failure. Therefore, the present meta-analysis aimed to compare biochemical markers of premature renal dysfunction between β-TM and healthy subjects and identify renal issues' prevalence in patients with β-TM. We searched PubMed, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Medline, Scopus, Web of Science, ScienceDirect, ProQuest, Google Scholar, and State Inpatient Databases (SIDs) without any language constraints for all relevant articles published up to April 2019. Out of 1458 articles published up to April 2019, 24 case-control and 22 crosssectional studies were investigated. The investigated levels of serum phosphorus, uric acid (UA), cystatin C, and ferritin were significantly different between β-TM patients and controls. The albumin/creatinine ratio (ACR), N-acetyl-β-D-glucosaminidase/creatinine (NAG/Cr) ratio, urinary and serum β2 microglobulin (β2MG), and serum ferritin levels were significantly higher in β-TM patients than in healthy individuals. However, glomerular filtration rate, creatinine clearance, and pretransfusion hemoglobin indicated a significantly lower rate. The general prevalence of renal glomerular and/or tubular defects in patients with β-TM was 50.22%. Urinary NAG, β2MG, ACR, and Scys-C may be early markers of renal dysfunction in patients with β-thalassemia major. An observation of elevated levels of these markers despite normal levels of other markers of renal dysfunction may indicate primary, subclinical injury to the renal tubules and glomeruli.

Commentary on Severe Hypophosphatemia: The Hidden Truth.

Mohamed & Raal highlight the importance of investigating hypophosphatemia biochemically to allow a diagnosis of the underlying aetiology. Both parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) facilitate phosphate excretion in the urine. The tubular maximum reabsorption of phosphate for glomerular filtration rate (TmP/GFR) is a measure of renal tubular capacity to reabsorb phosphate. TmP/GFR is therefore reduced in a calcipenic state (vitamin D and/or calcium deficiency) due to secondary hyperparathyroidism and in the phosphopenic state, either due to a primary renal tubular defect or excess circulating FGF23 (genetic defects in FGF23 degradation or increased FGF23 production such as tumor-induced osteomalacia [TIO]). PTH increases 1,25-(OH)2Vitamin D (calcitriol) production while FGF23 reduces it. In this case of severe symptomatic hypophosphatemia, the low TmP/GFR, inappropriately normal calcitriol in the context of hypophosphatemia, and elevated FGF23 confirmed FGF23-induced renal phosphate wasting. A nuclear medicine scan established the diagnosis of TIO and assisted in the localization of the lesion.

Long-Term Follow-Up of Renal Function in Children after Liver Transplantation-A Single Center Retrospective Study.

Chronic kidney disease (CKD) is a common complication after liver transplantation (LT). Its prevalence with modern immunosuppression regimens, especially in children, is variable depending on the transplantation era. The study included 61 pediatric patients with at least 10 years of follow-up after liver transplantation remaining under constant care of the Department of Pediatric Surgery and Organ Transplantation. The analysis included several tests: estimated glomerular function (eGFR), results of screening for renal tubular defects and blood concentrations of basic immunosuppressive drug-tacrolimus. CKD was diagnosed in 3% of children at 12 years after LT. The maintaining of tacrolimus concentrations >4 ng/mL in long-term observation was associated with a significant increase of microalbuminuria. The presence of microalbuminuria, regarded as a risk factor of CKD, confirmed the necessity of regular comprehensive assessment of patients in long-term follow-up.

Favorable Effects of Burosumab on Fibroblast Growth Factor 23-Related Osteomalacia: A Case Report

Background: Fibroblast growth factor 23 (FGF23) decreases serum phosphate levels by inhibiting proximal tubular phosphate reabsorption and intestinal phosphate absorption by decreasing serum 1,25-dihydroxyvitamin D level, thereby regulating phosphate metabolism. Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by FGF23 overproduction by tumor tissue. Resecting the responsible tumor is a radical treatment for TIO. When the responsible tumor is undetectable, phosphate and active vitamin D administration is recommended. However, supplementation alone is frequently insufficient to maintain phosphate levels and it is difficult to prevent the complications associated with medical therapy, including hypercalciuria and nephrocalcinosis. Recently, burosumab, a human monoclonal anti-FGF23 antibody, has been approved in Japan as a therapeutic agent for FGF23-related hypophosphatemia. Here, we present a patient with TIO effectively treated with burosumab in the absence of identification of tumour location. Clinical case: A 47-year-old female developed pain and edema of the feet; however, the cause could not be determined at local hospitals. Afterwards, she developed marked bone atrophy in the feet and was referred to our hospital. Her age at symptom onset, hypophosphatemia (serum P, 1.9 mg/dl, 2.7 mg/dl < n < 4.6 mg/dl), high serum FGF23 level (630 pg/ml, 16 pg/ml < n < 69 pg/ml), and decreased 1,25-dihydroxyvitamin D level (12.9 pg/ml, 20 pg/ml < n < 60 pg/ml) indicated FGF23-related osteomalacia. She was not having any medication at the time of diagnosis, including saccharified iron oxide or iron polymaltose. Urinary phosphate excretion increased without renal tubular defect; therefore, hypophosphatemic osteomalacia was diagnosed. MRI showed high signal intensity in the talus, sacral, and L5 vertebral regions, indicating multiple pseudofractures. Comprehensive imaging studies, including systemic CT scan and 111In-pentetreotide scintigraphy, did not reveal any tumors despite the suspicion of TIO. Next, we performed systemic venous sampling, which revealed high FGF23 level in the left external iliac vein. Second venous sampling limited to the left lower limb exhibited high FGF23 level in the posterior tibial vein. However, an additional imaging study limited to the left foot could not identify any tumors. Genetic variation was negative for potentially responsible genes, including PHEX and FGF23. We decided to administer burosumab to normalize serum phosphate level without phosphate supplementation. Within 2 months, pain was relieved and the visual analog scale scores also improved from 10 to 6. Moreover, bone MRI showed improved pseudofractures. Conclusion: Burosumab administration was effective for TIO of unknown origin, and it improved not only laboratory findings but also clinical symptoms in this case.

O12 Pulseless electrical activity arrest in a young woman: could renal tubular acidosis due to Sjögren’s syndrome be the underlying cause?

O12 Pulseless electrical activity arrest in a young woman: could renal tubular acidosis due to Sjögren’s syndrome be the underlying cause?

SUN-060 LATE PRESENTATION OF NEPHROTOXICITY DUE TO OXALIPLATIN

Oxaliplatin is a third-generation platinum derivative and considered less nephrotoxic than Cisplatin. It is frequently used as part of chemotherapy to treat various gastrointestinal tumors. Although hypokalemia, ATN and acute nephrotoxicity in the form of renal tubular acidosis due to Oxaliplatin has been reported; long term nephrotoxic effects of Oxaliplatin are not known. We report a novel case of 57- year old male who presented with muscle aches and electrolyte disturbances, several months after receiving oxaliplatin based chemotherapy. Patient had a premorbid history of diabetes mellitus, hypertension and he was diagnosed to have intrahepatic cholangiocarcinoma with neuroendocrine differentiation in September 2018. His creatinine was normal 74 umol/L at baseline. He received five cycles of chemotherapy with FOLFIRINOX (Folinic acid, Flourouracil, Irinotecan and Oxaliplatin). After five cycles he developed Oxaliplatin related ileus and nephropathy causing ATN and required few sessions of hemodialysis. Subsequently his kidney function improved partially with a new elevated baseline creatinine which was stable at 133 umol/L in February 2019. He presented on 28th September 2019 with severe muscle aches to emergency department (ED). His investigations done in ED revealed severe hypokalemia K 1.9 mmol/L, worsening of renal function, baseline creatinine had risen from 133 umol/L to 205 umol/L, he had severe metabolic acidosis with tCO 2 10, with normal anion gap 15 (range 7-16) and hyperchloremia 111 mmol/L, pH was 7.15. His serum phosphorus was low (0.63 mmol/L). Magnesium was normal. Urinary TTKG was calculated and was suggestive of urinary potassium loss. His Urinary Anion Gap was negative. He had glycosuria 4 + even though his blood sugars were well controlled. His urine pH was 5.5. Patient was treated with very high doses of potassium tricitrate and phosphorus supplements. He was discharged home after normalization of electrolytes and acid base status. Proximal renal tubular acidosis (type 2, pRTA) / Fanconi’s syndrome is characterized by bicarbonate wasting and low serum bicarbonate, proximal tubular dysfunction also leads to poor absorption of other substances, like glucose and phosphate. Further investigations were carried out to rule out other causes of Fanconi’s syndrome / Type 2 renal tubular acidosis in this patient. ANA, dsDNA, SPEP, IFE and serum Free light chain assay were all unremarkable. His Lactate was normal. A diagnosis of Fanconi’s syndrome and renal tubular acidosis type 2 (Proximal) due to remote exposure with Oxaliplatin was made. Fanconi’s syndrome due to platinum based drugs like Cisplatin and Oxaliplatin has been reported in Literature. Persistence of subtle partial renal tubular defects is well noted even after many months to years of exposure of Cisplatin but not with Oxaliplatin. We believe this is the first report of Type 2 pRTA and Fanconi’s syndrome presenting several months after exposure to Oxaliplatin. Physicians should be aware of unexpected late nephrotoxicity with Oxaliplatin use.

Correction

Topiramate (TMP) is a broad-spectrum anticonvulsant drug used to treat a wide variety of seizure disorders, for migraine prophylaxis, and for many other indications. An important side effect of TMP is metabolic acidosis, which is mediated by renal tubular defects. TMP inhibits carbonic anhydrase, an enzyme that is necessary for acid handling in the proximal renal tubule. Patients can present with asymptomatic serum electrolyte derangements, acute change in mental status, hyperventilation, cardiac arrhythmias, or other sequelae of metabolic acidosis and associated respiratory compensation. If taken chronically, TMP can cause renal stone formation, bone mineralization defects, and several other effects secondary to changes in serum and urine pH and electrolytes. There is no well-studied way to prevent metabolic acidosis in patients taking TMP, but physicians should be vigilant when prescribing this drug to patients with the history of renal diseases and other comorbidities, and aware of this potential etiology of metabolic acidosis. We present a literature review of the underlying mechanisms involved in the development of renal tubular acidosis secondary to TMP and its clinical consequences.

Congenital Chloride Diarrhea in a Bartter Syndrome Misdiagnosed Brazilian Patient

The differential diagnosis in children with hypokalemic hypochloremic alkalosis include a group of an inherited tubulopathies, such as Bartter Syndrome (BS) and Gitelman Syndrome (GS). However, some of the clinically diagnosed patients present no pathogenic mutation in BS/GS known genes. Therefore, one can conclude that a similar clinical picture may be caused by PseudoBartter Syndrome (PBS) conditions. PBS include acquired renal problems (ex.: use of diuretics) as well as genetic or acquired extrarenal problems such as cystic fibrosis or cyclic vomiting, respectively. The accurate diagnosis of BS/GS needs a rational investigation. First step is to rule out PBS and confirm the primary renal tubular defect. However, it is not easy in some situations. In this sense, we reported a patient that was referred to our service with the diagnosis of BS, but presented no mutation in BS/GS known genes. The whole-exome sequencing detected a SCL26A3 likely pathogenic mutation leading to the final diagnosis of Congenital Chloride Diarrhea (CCD). Reviewing the records, the authors noticed that liquid stools were mistaken for urine. In addition, urinary and fecal samples were collected at an inappropriate time. The fecal sample taken during dehydration led to a low fecal chloride level and urine taken soon after sodium and potassium chloride infusion led to a high urinary chloride fractional excretion. Based on this data, BS was misdiagnosed. Our goal is to report the first Brazilian CCD patient initially misdiagnosed as BS and discuss the difficulties to achieve the correct diagnosis in clinical practice.

Type II Renal Tubular Acidosis Secondary to Topiramate: A Review.

Topiramate (TMP) is a broad-spectrum anticonvulsant drug used to treat a wide variety of seizure disorders, for migraine prophylaxis, and for many other indications. An important side effect of TMP is metabolic acidosis, which is mediated by renal tubular defects. TMP inhibits carbonic anhydrase, an enzyme that is necessary for acid handling in the proximal renal tubule. Patients can present with asymptomatic serum electrolyte derangements, acute change in mental status, hyperventilation, cardiac arrhythmias, or other sequelae of metabolic acidosis and associated respiratory compensation. If taken chronically, TMP can cause renal stone formation, bone mineralization defects, and several other effects secondary to changes in serum and urine pH and electrolytes. There is no well-studied way to prevent metabolic acidosis in patients taking TMP, but physicians should be vigilant when prescribing this drug to patients with the history of renal diseases and other comorbidities, and aware of this potential etiology of metabolic acidosis. We present a literature review of the underlying mechanisms involved in the development of renal tubular acidosis secondary to TMP and its clinical consequences.

TINU-associated Fanconi syndrome: a case report and review of literature

BackgroundTubulo-interstitial Nephritis and Uveitis (TINU) syndrome is a rare oculo-renal inflammatory disease. Renal tubular defects are usually found, but full proximal tubular abnormalities have rarely been described.Case presentationWe report the case of a 55-year old woman, native from Morocco, presenting with bilateral, non-granulomatous, anterior uveitis, mild renal insufficiency, leucocyturia and glycosuria. Further work-up showed hypophosphatemia and hyperphosphaturia, hypouricemia and hyperuricosuria, and hyper aminoaciduria, consistent with Fanconi syndrome. A kidney biopsy was obtained and showed diffuse interstitial infiltrates with tubular necrosis. The patient improved after the initiation of a corticosteroid therapy, with tapering dose.ConclusionsWe reviewed the literature and found nine similar cases. This association mostly occurs in adult woman, without current evidence for an ethnic predilection, unlike previously reported. The renal prognosis seems favorable after corticosteroid therapy, even in case of severe renal injury. Nonetheless mild tubular defects may persist after treatment or spontaneous remission.

Adefovir dipivoxil induced hypophosphatemic osteomalacia in chronic hepatitis B: a comparative study of Chinese and foreign case series

BackgroundAdefovir dipivoxil (ADV)-induced renal tubular dysfunction and hypophosphatemic osteomalacia (HO) have been given great consideration in the past few years. However, no standard guidance is available due to a lack of powerful evidence from appropriate long-term prospective case-control studies and variations in the definition of renal adverse events. The aim of this study is to clarify clinical features of ADV-related HO in Chinese chronic hepatitis B patients with long-term ADV treatment in Chinese and non-Chinese comparative case series.MethodsRetrieval of case reports was based on Pubmed, CNKI, Wan Fang and VIP databases using the key words adefovir dipivoxil, hypophosphatemia, osteomalacia and Fanconi syndrome. We divided patients into Chinese (C group) and Foreign (F group) groups according to their nationality. Comparisons involving demographics, clinical manifestations, tests, treatment and prognosis were conducted between the two groups.ResultsOf the patients screened, 120 Chinese patients were identified in the C group, and 32 non-Chinese patients were identified in the F group. The average age of the C group was younger than that of the F group (51.89 years ±10.96 years versus 56.47 years ±11.36 years, t = − 2.084, P = 0.039). No significant difference was found in gender (male to female, 3.29:1 versus 3:1, χ2 = 0.039, P = 0.844). Although there was no significant difference in the duration of ADV therapy before ostalgia onset, the C group tended to develop adverse events earlier, by 2–3 years, while the F group developed adverse events at 4–5 years (Z = − 1.517, P = 0.129). Prognosis was good after adjustment of the ADV dose and supplemental administration of phosphate and calcitriol. Time to resolution of tubular dysfunction was commenced at the first month, and Chinese patients were more prone to recover in the first 3 months than non-Chinese patients (91.3% of patients in the C group versus 56.3% in the F group, Z = − 3.013, P = 0.003).ConclusionsSufficient attention is required for middle-aged males before and during exposure to long-term ADV therapy, regardless of nationality. The clinical picture, laboratory and radiograph alterations are important clues for those patients and are usually characterized by polyarthralgia, renal tubular dysfunction and mineralization defects. Implementation of an early renal tubular injury index is recommended for patients with higher risk, which would prevent further renal injury.

Metabolic alkalosis with multiple salt unbalance: an atypical onset of cystic fibrosis in a child

Dehydration with multiple salt abnormalities is frequently encountered in the paediatric emergency department, during acute illnesses complicated by loss of body fluids. Metabolic alkalosis is not a common finding in dehydrated children. The presence of unusual electrolyte unbalance, such as metabolic alkalosis, hyponatremia, hypochloremia and hypokalemia, without evidence of renal tubular defects, is named as pseudo-Bartter syndrome. It can occur in several clinical settings and, in infancy, it is described as a potential complication of cystic fibrosis. We report a case of pseudo-Bartter syndrome representing the onset of cystic fibrosis in childhood.

Nephrolithiasis and Nephrocalcinosis in Children with Glucose-Galactose Malabsorption: Report of Five Cases

Several reports described nephrolithiasis and nephrocalcinosis in children with glucose-galactose malabsorption (GGM). The etiology of renal stones in GGM is not known, but the chronic dehydration and concentrated urine complicating chronic diarrhea in GGM might be a possible mechanism. Few reports described nephrocalcinosis in association with hypercalcemia, hypercalciuria, and renal tubular defect. Both nephrolithiasis and nephrocalcinosis can present in the neonatal period at the time of diagnosis or manifest later during follow up. We are aware of eleven patients of GGM with nephrolithiasis reported worldwide, and eight patients of GGM with nephrocalcinosis. In this current report, we describe a total of five patients with GGM complicated with nephrolithiasis (three cases), and nephrocalcinosis (two cases). As far as we know, this series is the largest group of patients described with these complications in one report. We aim from this paper to deliver a message to the pediatricians and pediatric gastroenterologist to do regular ultrasonography of the kidneys in all patients of GGM at the time of diagnosis and during follow up to recognize these complications early and refer them in the right moment for management.

Cystinuria Associated with Different SLC7A9 Gene Variants in the Cat.

Cystinuria is a classical inborn error of metabolism characterized by a selective proximal renal tubular defect affecting cystine, ornithine, lysine, and arginine (COLA) reabsorption, which can lead to uroliths and urinary obstruction. In humans, dogs and mice, cystinuria is caused by variants in one of two genes, SLC3A1 and SLC7A9, which encode the rBAT and bo,+AT subunits of the bo,+ basic amino acid transporter system, respectively. In this study, exons and flanking regions of the SLC3A1 and SLC7A9 genes were sequenced from genomic DNA of cats (Felis catus) with COLAuria and cystine calculi. Relative to the Felis catus-6.2 reference genome sequence, DNA sequences from these affected cats revealed 3 unique homozygous SLC7A9 missense variants: one in exon 5 (p.Asp236Asn) from a non-purpose-bred medium-haired cat, one in exon 7 (p.Val294Glu) in a Maine Coon and a Sphinx cat, and one in exon 10 (p.Thr392Met) from a non-purpose-bred long-haired cat. A genotyping assay subsequently identified another cystinuric domestic medium-haired cat that was homozygous for the variant originally identified in the purebred cats. These missense variants result in deleterious amino acid substitutions of highly conserved residues in the bo,+AT protein. A limited population survey supported that the variants found were likely causative. The remaining 2 sequenced domestic short-haired cats had a heterozygous variant at a splice donor site in intron 10 and a homozygous single nucleotide variant at a branchpoint in intron 11 of SLC7A9, respectively. This study identifies the first SLC7A9 variants causing feline cystinuria and reveals that, as in humans and dogs, this disease is genetically heterogeneous in cats.

Documentation of renal glomerular and tubular impairment and glomerular hyperfiltration in multitransfused patients with beta thalassemia.

Urinary albumin to creatinine (ACR) and beta2 microglobulin to creatinine ratios (BCR) are the surrogate and robust markers of renal glomerulopathy and tubulopathy, respectively. These markers predict short-term renal deterioration and mortality in various conditions. We aimed to assess the frequency and predictors of glomerular and tubular defects, renal impairment, and hyperfiltration in 96 adult patients with beta thalassemia intermedia and major. ACR > 300 mg/g creatinine and BCR > 300 μg/g creatinine were used to define the renal glomerular and tubular damages, respectively. Glomerular filtration rate (eGFRcreat) was estimated according to 2009 the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Decreased eGFRcreat was defined as less than 60 mL/min per 1.73 m(2). Renal glomerular and/or tubular defects were observed in about 68.8 % of all patients. Forty percent of patients had glomerular hyperfiltration. None of the patients had a decreased eGFRcreat. T2* value ≤20 msec on cardiac magnetic resonance (cMR) was the only independent predictor of glomerular damage (p = 0.013). Use of alendronate was associated with less renal tubular damage (p = 0.007). Female gender and previous history of splenectomy were the independent predictors of glomerular hyperfiltration in multivariate analysis (p < 0.001 and p = 0.040, respectively). Renal tubular and glomerular damage is frequent in adult patients with thalassemia intermedia and major. T2* value on cMR was the only independent predictor of glomerular damage. However, since we did not explore all the parameters of iron, it is not possible to draw a definite conclusion about the association of cMR and glomerular damage. There is no association with cardiac iron overload/accumulation and tubular damage or hyperfiltration.

A Case of Adult onset Bartter Syndrome with Nephrocalcinosis

Bartter syndrome is a renal tubular defect in electrolyte transport characterized by hypokalemia, metabolic alkalosis, hyperreninemia, hyperaldosteronism, normal blood pressure, and other clinical symptoms. As a clinical and genetical heterogeneous disorder, this syndrome can be classified into two clinical variants, antenatal Bartter syndrome and classic Bartter syndrome according to the onset age. Nephrocalcinosis is common in antenatal Bartter syndrome, but is rare in classic Bartter syndrome. It can also be classified into five genetic subtypes by the underlying mutant gene, all of which are expressed in the tubular epithelial cells of the thick ascending limb of the loop of Henle. Patients with Bartter syndrome type 1, 2 and 4 present at a younger age than classic Bartter syndrome type 3. We have experienced a case of Bartter syndrome with nephrocalcinosis in a 42-year-old woman diagnosed by biochemical and radiologic studies. We had successful response with potassium chloride and spironolactone.

Image Diagnosis: Medullary Sponge Kidney

An 18-year-old man was evaluated for recurrent urinary tract infections (UTIs). His first infection was at age 15 with Escherichia coli; before this occurrence he had experienced an episode of reddish urine; had no episodes of stones, and had no other contributory past or family history. His serum creatinine was 0.9 mg/dL and his urinalysis was negative. His voiding cystourethrogram was negative. Because of his history, there was a suspicion for some structural disorder or stones. Subsequently his intravenous pyelogram (IVP) showed medullary sponge kidney (MSK) (Figure 1). Figure 1. Intravenous pyelogram showing the classic “paint-brush” (arrow) appearance of dilated contrast-filled tubules within the renal medulla, characteristic for medullary sponge kidney. Another patient with similar symptoms was evaluated with a computed tomographic urogram (CTU) (Figures 2 and ​and33). Figure 2. Computed tomographic urogram (precontrast) axial view demonstrating clusters of pyramidal medullary calcification (arrow), characteristic for medullary sponge kidney. Figure 3. Computed tomographic urogram (postcontrast) coronal view demonstrating dilated contrast-filled tubules within the renal medulla and pyramidal medullary calcifications (arrow). MSK is a congenital disorder that involves malformation of the terminal collecting ducts of renal tubules, which leads to formation of microscopic to large cysts in the medullary portion of both kidneys mostly, though it can be unilateral.1 The true prevalence of this disorder is not clear, though estimates range from 1 in 5000 to 1 in 20,000 people.2 Most patients have no family history, although a rare autosomal dominant form has been reported and MSK also can rarely occur in conjunction with other rare congenital abnormalities. It is more common in patients who are recurrent stone formers (mostly calcium oxalate and calcium phosphate) and in women. Most patients are asymptomatic. If patients do have clinical manifestations, they are caused by kidney stones, hematuria, and urinary tract infections. These mostly start presenting in the second and third decade of life. Other signs may also be renal tubular defects in acidification and urinary concentration. This disorder is mostly diagnosed during work-up for hematuria, recurrent stones, recurrent urinary tract infections, or incidentally discovered during work-up of urologic disorders, after radiologic study such as an IVP or CTU.3,4 There is no specific therapy that can treat the cysts of MSK. Once this diagnosis is made, it is imperative to follow recommendations for prevention and treatment of UTIs and stones. There are various guidelines for prevention of recurrent UTIs. Regarding stones, prevention methods include oral citrate supplements depending on 24-hour urine collection results and adequate hydration so as to maintain a urine output of greater than 2 liters. Although there is no guideline for surveillance or specialty referral once MSK is diagnosed, an initial nephrology referral can be useful. However, in cases of complications from infection or stone, specialty referral will be mandated. Prognosis is generally good. However, in cases of recurrent infections and stones, chronic kidney disease can develop.

A Case of Multiple Gastrointestinal Obstructions in a Newborn Presenting With Pseudo-Bartter’s Syndrome

Hypochloremic metabolic alkalosis occurs in pseudo-Bartter’s syndrome (PBS) without a primary renal tubular defect. Usually seen in cystic fibrosis, this syndrome can also be caused by recurrent vomiting for various reasons. We present a case of multiple gastrointestinal anomalies, each by itself capable of causing the clinical condition, in a 10-day-old infant with PBS. Int J Clin Pediatr. 2014;3(4):114-116 doi: http://dx.doi.org/10.14740/ijcp174w

Cystinosis as a lysosomal storage disease with multiple mutant alleles: Phenotypic-genotypic correlations.

Cystinosis is an autosomal recessive lysosomal storage disease with an unclear enzymatic defect causing lysosomal cystine accumulation with no corresponding elevation of plasma cystine levels leading to multisystemic dysfunction. The systemic manifestations include a proximal renal tubular defect (Fanconi-like), endocrinal disturbances, eye involvements, with corneal, conjunctival and retinal depositions, and neurological manifestations in the form of brain and muscle dysfunction. Most of the long-term ill effects of cystinosis are observed particularly in patients with long survival as a result of a renal transplant. Its responsible CTNS gene that encodes the lysosomal cystine carrier protein (cystinosin) has been mapped on the short arm of chromosome 17 (Ch17 p13). There are three clinical forms based on the onset of main symptoms: nephropathic infantile form, nephropathic juvenile form and non-nephropathic adult form with predominant ocular manifestations. Avoidance of eye damage from sun exposure, use of cystine chelators (cysteamine) and finally renal transplantation are the main treatment lines. Pre-implantation genetic diagnosis for carrier parents is pivotal in the prevention of recurrence.

Idiopathic Intracranial Hypertension Associated With Either Primary or Secondary Aldosteronism

BackgroundIdiopathic intracranial hypertension (IIH) is a syndrome consisting of headache, visual field defects and papilledema of uncertain etiology. The prospect was raised previously as to an association between aldosteronism and increased intracranial pressure in 2 middle-aged women with IIH and primary aldosteronism (PAL). Since then, 2 additional adults were identified and 2 other cases were reported from the United Kingdom, whereas 6 cases of IIH and secondary aldosteronism (SAL) in children have been reported in the English literature worldwide. MethodsA retrospective analysis of cases from author institutions and published literature comparing clinical features, laboratory findings and therapeutic interventions in these 12 cases. ResultsThe female-to-male ratio was 10:2. The mean age of the PAL patients was 49±3years—all hypertensive, with adrenal pathology in most. The mean age of the SAL patients was 11±2years—mostly normotensive, with 3 having Bartter’s and 2 Gitelman syndromes, and 1 renal congenital hypoplasia. Plasma aldosterone levels were elevated (31±5ng/dL) in PAL and SAL, whereas plasma renin activity was suppressed in PAL. Hypokalemia (3.2±0.2mmol/L), hypomagnesemia (1.6±0.3mg/dL) and a putative metabolic alkalosis (serum HCO3 30±1mmol/L) were observed. IIH symptoms were controlled by spironolactone in 5, amiloride in 1, correction of hypokalemia and hypomagnesemia in 2, discontinuation of nonsteroidal antiinflammatory drugs in 2, and reduction of body weight in 1. One patient required serial lumbar punctures, 2 a ventriculoperitoneal shunt, whereas all 3 patients with adrenal adenoma underwent surgical resection. ConclusionsAn association between IIH and PAL occurs in hypertensive middle-aged women, whereas normotensive girls having an inherited renal tubular defect may have IIH with SAL. Patients with IIH should be evaluated for aldosteronism and considered for spironolactone therapy.