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The Korean Journal of Gastroenterology... Mar 2020The consequences of graft failure after liver transplantation (LT) range far beyond the liver. The kidneys are often affected, where persistent and progressive...
The consequences of graft failure after liver transplantation (LT) range far beyond the liver. The kidneys are often affected, where persistent and progressive cholestasis can result in acute kidney injury (AKI) leading to the development of bile cast nephropathy (BCN). BCN is an often unrecognized condition that is characterized by proximal tubulopathy and the formation of bile casts in the distal tubules, which is almost diagnosed exclusively on a kidney biopsy or autopsy. This condition is potentially reversible, provided the bilirubin levels can be reduced early. LT may represent a treatment option in the case of irreversible liver (or liver graft) failure, which is beneficial for both the liver and the kidney. This paper reports a case of BCN in a patient with idiopathic graft failure after LT. Despite his chronic kidney disease, liver re-transplantation led to the successful improvement of his AKI.
Topics: Acute Kidney Injury; Bile Acids and Salts; Glomerular Filtration Rate; Graft Rejection; Humans; Kidney; Liver Transplantation; Male; Middle Aged; Transplantation, Homologous
PubMed: 32209806
DOI: 10.4166/kjg.2020.75.3.167 -
Metabolites Mar 2020Vitamin D is tightly linked with renal tubular homeostasis: the mitochondria of proximal convoluted tubule cells are the production site of 1α,25-dihydroxyvitamin D3.... (Review)
Review
Vitamin D is tightly linked with renal tubular homeostasis: the mitochondria of proximal convoluted tubule cells are the production site of 1α,25-dihydroxyvitamin D3. Patients with renal impairment or tubular injury often suffer from chronic inflammation. This alteration comes from oxidative stress, acidosis, decreased clearance of inflammatory cytokines and stimulation of inflammatory factors. The challenge is to find the right formula for each patient to correctly modulate the landscape of treatment and preserve the essential functions of the organism without perturbating its homeostasis. The complexity of the counter-regulation mechanisms and the different axis involved in the Vitamin D equilibrium pose a major issue on Vitamin D as a potential effective anti-inflammatory drug. The therapeutic use of this compound should be able to inhibit the development of inflammation without interfering with normal homeostasis. Megalin-Cubilin-Amnionless and the FGF23-Klotho axis represent two Vitamin D-linked mechanisms that could modulate and ameliorate the damage response at the renal tubular level, balancing Vitamin D therapy with an effect potent enough to contrast the inflammatory cascades, but which avoids potential severe side effects.
PubMed: 32204545
DOI: 10.3390/metabo10030115 -
Orphanet Journal of Rare Diseases Feb 2020Cystinosis is a rare autosomal recessive disorder caused by intracellular cystine accumulation. Proximal tubulopathy (Fanconi syndrome) is one of the first signs,...
BACKGROUND
Cystinosis is a rare autosomal recessive disorder caused by intracellular cystine accumulation. Proximal tubulopathy (Fanconi syndrome) is one of the first signs, leading to end-stage renal disease between the age of 12 and 16. Other symptoms occur later and encompass endocrinopathies, distal myopathy and deterioration of the central nervous system. Treatment with cysteamine if started early can delay the progression of the disease. Little is known about the neurological impairment which occurs later. The goal of the present study was to find a possible neuroanatomical dysmorphic pattern that could help to explain the cognitive profile of cystinosis patients. We also performed a detailed review of the literature on neurocognitive complications associated with cystinosis.
METHODS
17 patients (mean age = 17.6 years, [5.4-33.3]) with cystinosis were included in the study. Neuropsychological assessment was performed including intelligence (Intelligence Quotient (IQ) with Wechsler's scale), memory (Children Memory Scale and Wechsler Memory Scale), visuo-spatial (Rey's figure test) and visuo-perceptual skills assessments. Structural brain MRI (3 T) was also performed in 16 out of 17 patients, with high resolution 3D T1-weighted, 3D FLAIR and spectroscopy sequences.
RESULTS
Intellectual efficiency was normal in patients with cystinosis (mean Total IQ = 93). However the Perceptual Reasoning Index (mean = 87, [63-109]) was significantly lower than the Verbal Comprehension Index (mean = 100, [59-138], p = 0.003). Memory assessment showed no difference between visual and verbal memory. But the working memory was significantly impaired in comparison with the general memory skills (p = 0.003). Visuospatial skills assessment revealed copy and reproduction scores below the 50th percentile rank in more than 70% of the patients. Brain MRI showed cortical and sub-cortical cerebral atrophy, especially in the parieto-occipital region and FLAIR hypersignals in parietal, occipital and brain stem/cerebellum. Patients with atrophic brain had lower Total IQ scores compared to non-atrophic cystinosis patients.
CONCLUSIONS
Patients with cystinosis have a specific neuropsychological and neuroanatomical profile. We suggest performing a systematic neuropsychological assessment in such children aiming at considering adequate management.
Topics: Adolescent; Child; Cystinosis; Humans; Intelligence; Intelligence Tests; Neuropsychological Tests; Phenotype
PubMed: 32102670
DOI: 10.1186/s13023-019-1271-6 -
International Journal of Molecular... Jan 2020Dent disease (DD), an X-linked renal tubulopathy, is mainly caused by loss-of-function mutations in CLCN5 (DD1) and OCRL genes. CLCN5 encodes the ClC-5 antiporter that...
Dent disease (DD), an X-linked renal tubulopathy, is mainly caused by loss-of-function mutations in CLCN5 (DD1) and OCRL genes. CLCN5 encodes the ClC-5 antiporter that in proximal tubules (PT) participates in the receptor-mediated endocytosis of low molecular weight proteins. Few studies have analyzed the PT expression of ClC-5 and of megalin and cubilin receptors in DD1 kidney biopsies. About 25% of DD cases lack mutations in either CLCN5 or OCRL genes (DD3), and no other disease genes have been discovered so far. Sanger sequencing was used for CLCN5 gene analysis in 158 unrelated males clinically suspected of having DD. The tubular expression of ClC-5, megalin, and cubilin was assessed by immunolabeling in 10 DD1 kidney biopsies. Whole exome sequencing (WES) was performed in eight DD3 patients. Twenty-three novel CLCN5 mutations were identified. ClC-5, megalin, and cubilin were significantly lower in DD1 than in control biopsies. The tubular expression of ClC-5 when detected was irrespective of the type of mutation. In four DD3 patients, WES revealed 12 potentially pathogenic variants in three novel genes (SLC17A1, SLC9A3, and PDZK1), and in three genes known to be associated with monogenic forms of renal proximal tubulopathies (SLC3A, LRP2, and CUBN). The supposed third Dent disease-causing gene was not discovered.
Topics: Biomarkers; Biopsy; Chloride Channels; DNA Mutational Analysis; Dent Disease; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Immunohistochemistry; Kidney Diseases; Mutation; Exome Sequencing
PubMed: 31947599
DOI: 10.3390/ijms21020516 -
Kidney International Feb 2020Almost 30 years after the detection of chronic interstitial nephritis in agricultural communities (CINAC) its etiology remains unknown. To help define this we examined...
Almost 30 years after the detection of chronic interstitial nephritis in agricultural communities (CINAC) its etiology remains unknown. To help define this we examined 34 renal biopsies from Sri Lanka, El Salvador, India and France of patients with chronic kidney disease 2-3 and diagnosed with CINAC by light and electron microscopy. In addition to known histopathology, we identified a unique constellation of proximal tubular cell findings including large dysmorphic lysosomes with a light-medium electron-dense matrix containing dispersed dark electron-dense non-membrane bound "aggregates". These aggregates associated with varying degrees of cellular/tubular atrophy, apparent cell fragment shedding and no-weak proximal tubular cell proliferative capacity. Identical lysosomal lesions, identifiable by electron microscopy, were observed in 9% of renal transplant implantation biopsies, but were more prevalent in six month (50%) and 12 month (67%) protocol biopsies and in indication biopsies (76%) of calcineurin inhibitor treated transplant patients. The phenotype was also found associated with nephrotoxic drugs (lomustine, clomiphene, lithium, cocaine) and in some patients with light chain tubulopathy, all conditions that can be directly or indirectly linked to calcineurin pathway inhibition or modulation. One hundred biopsies of normal kidneys, drug/toxin induced nephropathies, and overt proteinuric patients of different etiologies to some extent could demonstrate the light microscopic proximal tubular cell changes, but rarely the electron microscopic lysosomal features. Rats treated with the calcineurin inhibitor cyclosporine for four weeks developed similar proximal tubular cell lysosomal alterations, which were absent in a dehydration group. Overall, the finding of an identical proximal tubular cell (lysosomal) lesion in CINAC and calcineurin inhibitor nephrotoxicity in different geographic regions suggests a common paradigm where CINAC patients undergo a tubulotoxic mechanism similar to calcineurin inhibitor nephrotoxicity.
Topics: Agriculture; Animals; France; Humans; India; Nephritis, Interstitial; Rats; Renal Insufficiency
PubMed: 31892415
DOI: 10.1016/j.kint.2019.11.009 -
Medicine Dec 2019Peptide receptor radionuclide therapy (PRRT) with radiolabeled somatostatin analogs is a targeted internal radiotherapy method used to treat tumors expressing...
RATIONALE
Peptide receptor radionuclide therapy (PRRT) with radiolabeled somatostatin analogs is a targeted internal radiotherapy method used to treat tumors expressing somatostatin receptors. Concomitant amino acids perfusion is systematically performed in order to inhibit the proximal tubular uptake of the radionuclide and thus prevent nephrotoxicity. PATIENT CONCERNS:: a 67-year-old woman with an intestinal neuroendocrine tumor with multiple lymphadenopathies and liver metastases. The patient displayed a carcinoid syndrome with flushes including facial erythrosis and paresthesia. During the treatment, the patient exhibited emesis and severe cramps.
DIAGNOSIS
We describe incomplete proximal tubulopathy induced by an amino acid therapy with [177Lu]-DOTA0-Tyr3-octreotate, which was reversible after treatment discontinuation. This diagnosis relies on metabolic acidosis, hypophosphatemia due to renal loss, tubular proteinuria and generalized aminoaciduria. Serum creatinine remained stable during and after the procedure.
INTERVENTIONS
PRRT with radiolabeled somatostatin analog ([177Lu]-DOTA0-Tyr3-octreotate). In order to prevent PRRT induced nephrotoxicity, we used a solution of 20 amino acids including 22 g/L Lysine and 16.8 g/L Arginine. Metoclopramide was successfully used to control vomiting. During the treatment and at the time of cramps, the blood sample showed hypophosphatemia at 0.3 mmol/L justifying intravenous phosphate supplementation. The cramps disappeared after this infusion.
OUTCOMES
Hypophosphatemia with low TmPO4/GFR was observed as well as an increase in β2-microglobulinuria, urinary polyclonal light chains, and amino aciduria involving all amino acids. All these disturbances disappeared the day after the treatment and there was no acute kidney injury after 5 PRRT sessions. Six months after PRRT discontinuation, the patient had neither renal failure nor proximal tubulopathy. Aminoacid induced tubulopathy involves the main ligands of the megalin receptor. It has recently been demonstrated that cilastatin is a megalin inhibitor in the proximal tubule and therefore could represent an attractive alternative to amino acids for this purpose.
LESSONS
This case report is a description of a nephroprotective strategy in which partial, and transient tubulopathy is induced, in order to decrease proximal absorption of a tubulotoxic molecule. This little known strategy could be used to prevent proximal tubular injury caused by others megalin-mediated nephrotoxicity medication.
Topics: Aged; Amino Acids; Fanconi Syndrome; Female; Humans; Intestinal Neoplasms; Kidney Tubules, Proximal; Neuroendocrine Tumors; Octreotide; Organometallic Compounds; Radioisotopes; Receptors, Peptide
PubMed: 31876733
DOI: 10.1097/MD.0000000000018478 -
Pediatric Nephrology (Berlin, Germany) Apr 2020Lowe syndrome and Dent-2 disease are caused by mutations in the OCRL gene, which encodes for an inositol 5-phosphatase. The renal phenotype associated with OCRL...
BACKGROUND
Lowe syndrome and Dent-2 disease are caused by mutations in the OCRL gene, which encodes for an inositol 5-phosphatase. The renal phenotype associated with OCRL mutations typically comprises a selective proximal tubulopathy, which can manifest as Fanconi syndrome in the most extreme cases.
METHODS
Here, we report a 12-year-old male with nephrotic-range proteinuria and focal segmental glomerulosclerosis on renal biopsy. As a glomerular pathology was suspected, extensive investigation of tubular function was not performed.
RESULTS
Surprisingly, whole exome sequencing identified a genetic variant in OCRL (c1467-2A>G) that introduced a novel splice mutation leading to skipping of exon 15. In situ hybridisation of adult human kidney tissue and zebrafish larvae showed OCRL expression in the glomerulus, supporting a role for OCRL in glomerular function. In cultured podocytes, we found that OCRL associated with the linker protein IPIP27A and CD2AP, a protein that is important for maintenance of the podocyte slit diaphragm.
CONCLUSION
Taken together, this work suggests a previously under-appreciated role for OCRL in glomerular function and highlights the importance of investigating tubular function in patients with persistent proteinuria.
Topics: Animals; Child; Chloride Channels; Glomerulosclerosis, Focal Segmental; Humans; Kidney Glomerulus; Male; Mutation; Oculocerebrorenal Syndrome; Phosphoric Monoester Hydrolases; Podocytes; Proteinuria; Exome Sequencing; Zebrafish
PubMed: 31811534
DOI: 10.1007/s00467-019-04317-4 -
Jornal Brasileiro de Nefrologia Mar 2020
Topics: Acute Kidney Injury; Albuminuria; Anti-Inflammatory Agents; Antineoplastic Agents; Bortezomib; Creatinine; Crystallization; Cyclophosphamide; Dexamethasone; Diagnosis, Differential; Drug Therapy, Combination; Humans; Hypokalemia; Immunoglobulin kappa-Chains; Immunosuppressive Agents; Kidney Diseases; Kidney Tubules, Proximal; Male; Microscopy, Electron, Transmission; Middle Aged; Paraproteinemias; Podocytes; Treatment Outcome
PubMed: 31799982
DOI: 10.1590/2175-8239-JBN-2019-0086 -
European Journal of Case Reports in... 2019Acquired causes of Fanconi syndrome in adults are usually due to drugs, toxins or paraproteinaemias. Infectious causes are rarely described. We report a case of invasive...
UNLABELLED
Acquired causes of Fanconi syndrome in adults are usually due to drugs, toxins or paraproteinaemias. Infectious causes are rarely described. We report a case of invasive pneumococcal disease in a patient who developed a Fanconi-like syndrome during the course of her illness. This patient presented with multiple electrolyte derangements consisting predominantly of hypokalaemia, hypomagnesaemia and hypophosphataemia during hospitalization for invasive pneumococcal disease with possible Austrian syndrome. Further evaluation revealed significant urinary losses of these electrolytes, uric acid and β2-microglobulin. Together with evidence of hypouricaemia, this is suggestive of proximal renal tubulopathy, and hence a Fanconi-like syndrome. The patient's clinical condition and biochemical anomalies improved following pneumococcus treatment.
LEARNING POINTS
Suspect Fanconi syndrome when there are multiple electrolyte derangements consisting of hypokalaemia, hypomagnesaemia and hypophosphataemia.Recognise the common causes of Fanconi syndrome and appreciate that infections such as legionellosis, leptospirosis and pneumococcal disease can potentially result in Fanconi syndrome.The management of Fanconi syndrome is generally supportive and involves treating the underlying cause.
PubMed: 31742198
DOI: 10.12890/2019_001230 -
Journal of Pediatric Genetics Dec 2019Dent disease is a rare X-linked renal proximal tubulopathy presenting with low-molecular-weight proteinuria (LMWP), hypercalciuria, and nephrocalcinosis, other signs of...
Dent disease is a rare X-linked renal proximal tubulopathy presenting with low-molecular-weight proteinuria (LMWP), hypercalciuria, and nephrocalcinosis, other signs of incomplete renal Fanconi syndrome, and renal failure. Early identification of patients who harbor disease-associated mutations is important for effective medical care and avoidance of unnecessary interventions. We report the case of an asymptomatic 9-year-old boy who presented with proteinuria in routine examination. Further investigation revealed the presence of nephrotic range proteinuria, mostly LMWP and mild hypercalciuria without nephrocalcinosis, or other features of tubular dysfunction. Renal function, growth, and bone mineral density were within regular limits. The male gender and the presence of LMWP and hypercalciuria even in the absence of other findings prompted us to genetic investigation for Dent disease. A novel splice site mutation (c.416-2A > G) of the chloride voltage-gated channel 5 ( ) gene, responsible for Dent disease type 1 was identified. analysis revealed that this mutation interferes with the mating of exons 4 and 5. Due to early molecular diagnosis, our patient did not undergo a renal biopsy, neither required aggressive pharmacological interventions. This case underscores the diversity and complexity of mutations and highlights the importance of early molecular testing in male patients with incomplete phenotype of Dent disease.
PubMed: 31687264
DOI: 10.1055/s-0039-1692172