Clinical exome sequencing is a powerful tool in the diagnostic flow of monogenic kidney diseases: an Italian experience.

BACKGROUND: A considerable minority of patients on waiting lists for kidney transplantation either have no diagnosis (and fall into the subset of undiagnosed cases) because kidney biopsy was not performed or histological findings were non-specific, or do not fall into any well-defined clinical category. Some of these patients might be affected by a previously unrecognised monogenic disease. METHODS: Through a multidisciplinary cooperative effort, we built an analytical pipeline to identify patients with chronic kidney disease (CKD) with a clinical suspicion of a monogenic condition or without a well-defined diagnosis. Following the stringent phenotypical and clinical characterization required by the flowchart, candidates meeting these criteria were further investigated by clinical exome sequencing followed by in silico analysis of 225 kidney-disease-related genes. RESULTS: By using an ad hoc web-based platform, we enrolled 160 patients from 13 different Nephrology and Genetics Units located across the Piedmont region over 15 months. A preliminary "remote" evaluation based on well-defined inclusion criteria allowed us to define eligibility for NGS analysis. Among the 138 recruited patients, 52 (37.7%) were children and 86 (62.3%) were adults. Up to 48% of them had a positive family history for kidney disease. Overall, applying this workflow led to the identification of genetic variants potentially explaining the phenotype in 78 (56.5%) cases. CONCLUSIONS: These results underline the importance of clinical exome sequencing as a versatile and highly useful, non-invasive tool for genetic diagnosis of kidney diseases. Identifying patients who can benefit from targeted therapies, and improving the management of organ transplantation are further expected applications.

Acute Kidney Injury and Chronic Kidney Disease in the Elderly and Polypharmacy.

BACKGROUND: Acute kidney injury (AKI) incidence is reported to be 10 times higher in aged people. Related to their higher prevalence of chronic kidney disease (CKD), older patients are at high risk of toxic effects driven by drugs. METHODS: The demographics, hospitalizations, visits to the Emergency Department, pharmacological therapy, and lab tests were analyzed in 71,588 individuals. RESULTS: Data showed a higher prevalence of AKI as well as CKD in the elderly as compared to the younger group, with an associated very high mortality. A broad number of drugs was prescribed, ranging from 1 to 35, the majority being between 5 and 9 drugs. CONCLUSION: Elderly patients who developed AKI had a higher number of hospitalizations (underlying frailty), were more likely to progress to more severe stages of CKD and to be affected by other non-renal pathologies (associated comorbidities) and to be given heavier pharmacological prescriptions (polypharmacy).

[Bardet-Biedl syndrome and Kidney failure: a case report].

Bardet-Biedl Syndrome (BBS) is a rare multi-systemic disease with autosomal recessive transmission. BBS was at first considered to be homogeneous as for its genetics, but subsequent studies have shown an extensive gene variability. Currently, 21 genes (BBS1-21) present on different chromosomes have been mapped: these genes are responsible for BBS phenotypes and they show a great heterogeneity of mutations.The most common genes are BBS1 (locus 11q13) and BBS10.We show here the case of a 50 year old patient with BBS. Medical History: retinitis pigmentosa at 4 years of age evolved to complete blindness, generalized epilepsy crises, poly-syndactyly, left-hand malformation. In April 1986 developed an epileptic episode: on that occasion Chronic Kidney Failure (CKF) diagnosis and starting of haemodialysis. In 1989, hospitalization for epileptic seizures. In 2009 the patient underwent kidney transplantation from deceased donor. Immunosuppressive initial protocol: Basiliximab, Azathioprine, Tacrolimus, Steroid, and Tacrolimus, Azathioprine, Steroid at hospital discharge. Post-operative care complicated by respiratory failure with mechanical ventilation assistance. During hospitalization, the neurological picture remained stable. At hospital discharge Creatinine 1.8 mg/dl. Subsequently, immunosuppressant were gradually tapered until monotherapy with Tacrolimus. At present the patient's conditions appear to be good, renal function has remained substantially stable with Creatinine between 1.4-1.5 mg/dl and glomerular filtration rate (GFR) estimated at 39-42 mL/min/1.73 m ² according to MDRD study Equation. This case shows the possibility to successfully manage a BBS-affected uremic patient, despite the complexity of the pathology and the aggravating factor of extreme rarity in diagnostic pathway.

[Clinical competence in Nephrology: proposal of an evaluation pathway and definition of professional levels]. / Le competenze in Nefrologia: proposta di un percorso di valutazione e di definizione di livelli professionali.

The need to assess clinical competencies in a medical environment is an intriguing issue due to progressive involvement of young physicians in clinical practice, as well as for connections tied to evaluation systems to define postgraduate training and career progression. To reach this goal, system must be based upon contributions that are aimed to achieve a clear and homogeneous evaluation pathway and strictly related to the continuing medical education institution (credits). All these presuppositions are instrumental for the proposal of a sheet which could allow a data retrieval useful to depict a career progression by means of: identification of reproducible parameters along with clear standards; advices for indicators; objective judgments that could drive to a score meaningful for reaching higher steps in the performance evaluation. This work had been carried out at Local Health Authority 1 of Cuneo (ASLCN1) from 2014 to 2017 in order to provide a widely usable evaluation framework for all the medical workers. Aim of this work is thus to show up an original methodology, as much as possible based upon objective items, related to the professional improvement of a nephrologist working in Hospital and following him along his clinical course.

[Hyperuricemia and gene mutations: a case report].

Hyperuricemia is frequently found in nephrology. The case presented may be useful to clarify some pathogenetic aspects. It is a patient of 18 years, hyperuricaemic. Non-consanguineous parents, hyperuricemia in the paternal line, not neuropsychiatric disorders in the family. Delay in neuromotor acquisitions, average intellectual disabilities, anxiety disorder, obsessive-compulsive personality traits. Normal renal function and renal ultrasound. Evidence of hyperuricemia in 2015. Never gouty episodes and / or lithiasis, initiated allopurinol 100 mg on alternate days, with no side effects, urea in the control range, slightly below normal uricuria. Given the complex clinical, he carried out a genetic analysis of array-CGH. He showed a deletion on the short arm of chromosome 3 (3p12.3) and a duplication of the long arm of chromosome 1 (19q13-42). The deletion 3p12.3 (paternal inheritance), involves the ROBO2 gene. Duplication 19q13.42, (maternal inheritance), includes NLRP12, DPRX, ZNF331 genes. The ROBO2 gene with its mutation, is associated with vesicoureteral reflux. The NLRP12 gene encodes proteins called "Nalps", forming a subfamily of proteins "CATERPILLAR". Many "Nalps" as well as the "Nalps 12" have an N-terminal domain (DYP) with a purin. Since uric acid is a byproduct of purine metabolism, considered the familiarity, we believe that we can hypothesize that the mutations found. In particular those concerning the NLRP-12 gene, may have a role in the presence of hyperuricemia. We believe that in patients with hyperuricemia, associated with a particular impairment of neurological picture, it is likely that there is a subtended common genetic deficiency.

Neutrophil Gelatinase Associated Lipocalin Is an Early and Accurate Biomarker of Graft Function and Tissue Regeneration in Kidney Transplantation from Extended Criteria Donors.

BACKGROUND: Delayed graft function (DGF) is an early complication of kidney transplantation (KT) associated with increased risk of early loss of graft function. DGF increases using kidneys from extended criteria donors (ECD). NGAL is a 25KDa protein proposed as biomarker of acute kidney injury. The aim of this study was to investigate the role of NGAL as an early and accurate indicator of DGF and Tacrolimus (Tac) toxicity and as a mediator of tissue regeneration in KT from ECD. METHODS: We evaluated plasma levels of NGAL in 50 KT patients from ECD in the first 4 days after surgery or after Tac introduction. RESULTS: Plasma levels of NGAL at day 1 were significantly higher in DGF group. In the non DGF group, NGAL discriminated between slow or immediate graft function and decreased more rapidly than serum creatinine. NGAL increased after Tac introduction, suggesting a role as marker of drug toxicity. In vitro, hypoxia and Tac induced NGAL release from tubular epithelial cells (TEC) favoring an autocrine loop that sustains proliferation and inhibits apoptosis (decrease of caspases and Bax/Bcl-2 ratio). CONCLUSIONS: NGAL is an early and accurate biomarker of graft function in KT from ECD favoring TEC regeneration after ischemic and nephrotoxic injury.

[Hypokalemia in Lennox-Gastaut syndrome]. / Ipopotassiemia in sindrome di Lennox-Gastaut.

The Lennox-Gastaut Syndrome (LGS) is a childhood epileptic encephalopathy. Incidence: 1/1.000.000/year, prevalence: 15/100.000. LGS covers 5-10% of epileptic patients and 1-2% of childhood epilepsies. Also referred to as cryptogenic or symptomatic generalized epilepsy. LGS is characterized by: multiple seizures (atypical absences, axial tonic seizures and sudden atonic or myoclonic falls), diffuse slow cryptic EEG waves when awake (<3 Hz), fast rhythmic peaks (10 Hz) during sleep, mental retardation and personality disorders. The LGS is not responding to treatment. Some new drugs have proven to be effective in controlling the disease (Felbamate, Lamotrigine, Topiramate, Levetiracetam). The mortality rate is about 5%; only rarely death is due to epilepsy, which is usually caused by stroke or epileptic episodes. Here we describe the case of a 45-year-old female patient with LGS, severe hypokalemia, mental retardation and focal seizures. Normal renal function: creatinine 0.9 mg/dl, urea 26 mg/dl, creatinine clearance 96 ml/min, serum potassium levels to the minimum: 3.5 mEq/L. This level of potassium, however, had been achieved with the assumption of 8 oral tablets/day of potassium chloride. Osmotic diuresis, use of diuretics, Bartter, Gitelman (normal urinary calcium and magnesium) and pseudo-Bartter syndromes were all excluded whereas aldosteronism was found. Our findings lead to hypokalemia related to assumption of topiramate and hyperaldosteronism. Reduction in drug intake was not effective due to the increased seizures, so the drug was maintained, along with potassium supplementation. In conclusion, the patient has been diagnosed with hypokalemia and iatrogenic hyperaldosteronism, rare in our outpatient practice.

[Rhabdomyolysis from gabapentin: a case report]. / Rabdomiolisi da gabapentin: a case report.

Gabapentin (GBP) is a drug with different indications.Is not metabolized and is excreted by the kidney. The common side effects are: arthralgia, myalgia, fatigue, dizziness and ataxia. Rhabdomyolysis is an extremely rare side effect. This latter, that can be caused by trauma, strenuous exercise, infections, drugs and toxins, is a syndrome characterized by loss of skeletal muscle resulting in the release of myocyte components in the circulation. Following a case of rhabdomyolysis caused by GBP in patient with chronic renal failure (CRF). A 65-year-old diabetic men, in peritoneal dialysis (PD), affected by ischemic and hypokinetic cardiomyopathy, sensorimotor neuropathy. The patient reported: weakness, diffuse myalgias, hypotension. He had been taking GBP for three days, after the failure of therapies with tricyclic antidepressants, opioids and NSAIDs. Laboratory tests confirmed the increase of the indices of muscle necrosis.The immediate withdrawal of the drug in association with CAPD dialysis treatment, led to improvement of the clinical and biochemical parameters. During the last 10 years, 3 cases of rhabdomyolysis referred to the assumption of GBP have been reported. The use of PD for treatment of acute renal failure, has been significantly reduced over the years. The effectiveness of the purification method is much lower than the one with the continuous extracorporeal treatments. In conclusion, GBP may be associated with rhabdomyolysis. Since GBP toxicity in CRF patients is often overlooked, a better awareness of this phenomenon and a thorough follow-up of laboratory tests to detect any possible early adverse reaction is suggested.

[Acute pielonephritis and renal abscesses in Piedmont and Aosta Valley]. / Indagine sulla pielonefrite acuta e sugli ascessi renali in Piemonte e Valle d'Aosta.

The Piedmont Group of Clinical Nephrology compared the activity of 18 nephrology centers in Piedmont and Aosta Valley as regards acute pielonephritis (APN). Data from more than 500 cases per year of APN were examined. The microbial spectrum of APN consists mainly of Escherichia coli and Klebsiella pneumoniae. Diagnosis was based on both clinical and radiological criteria in most of the centers (computed tomography-CT o Magnetic Resonance Imaging-MRI). In four centers diagnosis was made with the radiological criteria and in one center only with the clinical features. CT and MRI were performed in about 47% and 44% of cases respectively. Urine culture was positive in 22 up to 100% of cases. The most commonly used antibiotics were fluoroquinolones (ciprofloxacin or levofloxacin) and ceftriaxone (50% of centers) or amoxicillin/clavulanic acid (25% of centers). In 75% of the centers, patients received a combination of two antibiotics (aminoglycoside in 22% of them ). In 72% of the centers, almost 50% of the patients were re-examined, while 38.8% of centers re-examined all the patients. Renal ultrasound was inappropriate to identify abscesses. The mean of patients in whom renal abscesses were detected by CT or MRI was 18.2%. The analysis shows a high variability in the way of diagnosing and treating APN in Piedmont and Aosta Valley regions. This suggests that even if APN is a frequent pathological condition, practical recommendations are required.

[Prune-Belly Syndrome: a case report]. / Sindrome Prune-Belly: un caso clinico.

Prune-Belly Syndrome (PBS) is a rare congenital syndrome characterized by the absence of abdominal muscles, anomalies in the urinary tract, megaureter, cryptorchidism or testicular agenesis, hypertension and worsening chronic kidney disease (CKD). The incidence is estimated between 1 out of 35,000 and 1 out of 50,000 born alive, and it affects males in prevalence (97%). In the present study we describe the case of a 38 year old male patient (followed since May 2011) affected by PBS, CKD, one functional kidney at the scintigraphy, pediatric testicular implants, bladder surgery and correction of pectus excavatum. At the beginning of the observation, renal function was deteriorated, with a creatinine 3.3 mg/dl, GFR calculated at MDRD 23 ml/min, proteinuria in nephrotic range (4 g/day), high blood pressure, anemia and hyperparathyroidism. In the following examinations renal function framework worsened, despite the adoption of a low-protein diet. Due to the functional trend, the patient was prescribed hemodialysis as substitute treatment. In January 2013 a first attempt of artero-venous fistula (AVF) did not succeed, while a new AVF in March 2013 resulted effective. In July hemodialysis was started. In the future, we expect to insert the patient in the Kidney Transplant List (since surgical feasibility has already been positively evaluated). Our case is quite peculiar due to the late beginning of substitute treatment. Further, SPB represents a challenge that, in the absence of a prompt and effective treatment, inevitably it leads to terminal uremia; nevertheless, given a proper treatment, a transplant with good chances of success can be envisaged.

[Chronic uremia and palliative care]. / Insufficienza renale cronica "end stage": cure intensive e cure palliative.

Nowadays the choice to start with a renal replacement therapy (or its withdrawal once begun) is a critical issue leading to review the paradigm of constantly treating terminal uremia by means of dialysis technologies, without caring for effective prognosis nor for patients preferences, in a more affordable physician-patient relationship. Furthermore dialysis patients mean age is increasing and such population bears the burden of comorbidities that seriously affect survival and quality of life. In any case, dialysis withdrawing does not mean neglecting the patient: the start, or continuation of a very low protein diet program may represent a reasonable alternative, not only for uremic symptoms control but also providing a slowing of disease progression (at least postponing further the start of renal replacement therapy). Basically, in our opinion, the decision to start dialysis in an eligible patient, mainly in the elderly or frails, it should be driven by an adequate balance among all the factors. These factors play a role not only concerning survival, but also in life quality issues and patients preferences. Thus, we argue that ethical issues must be taken into account as well as compelling clinical factors which usually nephrologists refer to. To pursue this goal, it could be useful to set up specific educational pathways addressed to physicians, nurses and technicians of renal units. It also could be instrumental in developing new strategies to manage end stage renal failure, considering not only hospital facilities,but also nursing and patients homes. Incoming guidelines could help nephrologists in improving their behaviors to face these new issues.

A case of recurrent proliferative glomerulonephritis with monoclonal IgG deposits after kidney transplant treated with plasmapheresis.

Proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) is a rare and recently identified disease with a poor prognosis irrespective of the treatment. Recently, the possibility of recurrent or de novo PGNMID after kidney transplantation has been reported, which is associated with a better prognosis compared to PGNMID on native kidneys. Nevertheless, at present, due to the very few cases of recurrent PGNMID diagnosed, there is no proven effective treatment. Here, we report a case of recurrent PGNMID successfully treated with plasmapheresis, steroids and mycophenolate mofetil. Our report suggests that plasmapheresis might be a valid therapeutic option to treat recurrent PGNMID.