World Journal of Nephrology最新文献

Onco-Nephrology is an emerging subspecialty of Nephrology that focuses on a broad spectrum of renal disorders that can arise in patients with cancer. It encompasses acute kidney injury (AKI), complex fluid, electrolyte, and acid-base disorders, as well as chronic kidney disease caused or exacerbated by cancer and/or its treatment. In many such scenarios including AKI and hyponatremia, objective evaluation of hemodynamics is vital for appropriate management. Point of care ultrasonography (POCUS) is a limited ultrasound exam performed at the bedside and interpreted by the treating physician intended to answer focused clinical questions and guide therapy. Compared to conventional physical examination, POCUS offers substantially higher diagnostic accuracy for various structural and hemodynamic derangements. In this narrative review, we provide an overview of the utility of POCUS enhanced physical examination for the Onconephrologist supported by the current evidence and our experience-based opinion.

Stone formation is induced by an increased level of urine crystallization promoters and reduced levels of its inhibitors. Crystallization inhibitors include citrate, magnesium, zinc, and organic compounds such as glycosaminoglycans. In the urine, there are various proteins, such as uromodulin (Tamm-Horsfall protein), calgranulin, osteopontin, bikunin, and nephrocalcin, that are present in the stone matrix. The presence of several carboxyl groups in these macromolecules reduces calcium oxalate monohydrate crystal adhesion to the urinary epithelium and could potentially protect against lithiasis. Proteins are the most abundant component of kidney stone matrix, and their presence may reflect the process of stone formation. Many recent studies have explored the proteomics of urinary stones. Among the stone matrix proteins, the most frequently identified were uromodulin, S100 proteins (calgranulins A and B), osteopontin, and several other proteins typically engaged in inflammation and immune response. The normal level and structure of these macromolecules may constitute protection against calcium salt formation. Paradoxically, most of them may act as both promoters and inhibitors depending on circumstances. Many of these proteins have other functions in modulating oxidative stress, immune function, and inflammation that could also influence stone formation. Yet, the role of these kidney stone matrix proteins needs to be established through more studies comparing urinary stone proteomics between stone formers and non-stone formers.

Obstructive uropathy is an important cause of acute and chronic kidney disease. Decompression of the urinary tract is an essential aspect of treatment. The cause and aetiology of obstruction typically determine the surgical approach. Acute relief of obstruction is frequently complicated by fluid and electrolyte imbalance. Standard therapeutic interventions for acute or chronic renal failure also apply for cases of obstructive uropathy. This narrative review summarises the early and long-term medical management of obstructive uropathy.

Specialized centers are needed for nephrology and urology care of children. The justifications are the specialized nature of care needed and the growing incidence and prevalence. Children with chronic kidney disease (CKD) are at risk of morbidity, mortality, and decreased quality of life. Current pediatric practice structures are apparently poorly suited for the increasing demands of chronic disease in children. Kidney diseases account for around 8%-10% of total outpatients and 12% of admissions to the pediatric ward in hospitals. The major causes of pediatric CKD in registries are congenital anomalies of the kidney and urinary tract (around 50%), followed by inherited nephropathies and glomerulonephritis. The nephrologist's role is important for specialized investigations and treatment. Urologist's services are essential for the wide variety of conditions from birth to early adult age for complete cure and complementing medical management. Children have a right to treatments and to resources that are as sophisticated and advanced as those available to adults. Simple and sophisticated care for all children with ailments of the kidneys and related structures is important for ensuring 'health for all'. The availability of 'Child Kidney Care Centers' will go a long way in improving the lives of affected children.

There is a well-known relationship between malignancy and impairment of kidney functions, either in the form of acute kidney injury or chronic kidney disease. In the former, however, bilateral malignant ureteral obstruction is a surgically correctable factor of this complex pathology. It warrants urgent drainage of the kidneys in emergency settings. However, there are multiple controversies and debates about the optimal mode of drainage of the bilaterally obstructed kidneys in these patients. This review addressed most of the concerns and provided a comprehensive presentation of this topic from the recent literature. Also, we provided different perspectives on the management of the bilateral obstructed kidneys due to malignancy. Despite the frequent trials for improving the success rates and functions of ureteral stents, placement of a percutaneous nephrostomy tube remains the most recommended tool of drainage due to bilateral ureteral obstruction, especially in patients with advanced malignancy. However, the disturbance of the quality of life of those patients remains a major unresolved concern. Beside the unfavorable prognostic potential of the underlying malignancy and the various risk stratification models that have been proposed, the response of the kidney to initial drainage can be anticipated and evaluated by multiple renal prognostic factors, including increased urine output, serum creatinine trajectory, and time-to-nadir serum creatinine after drainage.

Acute post-streptococcal glomerulonephritis (APSGN) is the major cause of acute glomerulonephritis among children, especially in low- and middle-income countries. APSGN commonly occurs following pharyngitis due to the activation of antibodies and complements proteins against streptococcal antigens through the immune-complex-mediated mechanism. APSGN can be presented as acute nephritic syndrome, nephrotic syndrome, and rapidly progressive glomerulonephritis, or it may be subclinical. The management of APSGN is mainly supportive in nature with fluid restriction, anti-hypertensives, diuretics, and renal replacement therapy with dialysis, when necessary, as the disease is self-limiting. Congestive heart failure, pulmonary edema, and severe hypertension-induced encephalopathy might occur during the acute phase of APSGN due to hypervolemia. APSGN generally has a favorable prognosis with only a small percentage of patients with persistent urinary abnormalities, persistent hypertension, and chronic kidney disease after the acute episode of APSGN. Decreased complement levels, increased C-reactive protein, and hypoalbuminemia are associated with disease severity. Crescent formations on renal biopsy and renal insufficiency on presentation may be the predictors of disease severity and poor outcomes in APSGN in children.

When the physiopathology of membranous nephropathy was first described, almost 30% of cases were recognized to be secondary to well-known diseases such as autoimmune diseases, tumors or infections. The remaining 70% cases were called primary membranous nephropathy as the exact mechanism or pathogenic factor involved was unknown. The discovery of the M type phospholipase A2 receptor and thrombospondin type 1 domain containing 7A as causative antigens in these "so called" primary membranous nephropathies provided new insights into the effective causes of a large proportion of these cases. Novel techniques such as laser microdissection and tandem mass spectrometry as well as immunochemistry with antibodies directed against novel proteins allowed the confirmation of new involved antigens. Finally, using confocal microscopy to localize these new antigens and immunoglobulin G and Western blot analysis of serum samples, these new antigens were detected on the glomerular membrane, and the related antibodies were detected in serum samples. The same antigens have been recognized in some cases of secondary membranous disease due to autoimmune diseases, tumors and infections. This has allowed examination of the relationship between antigens in primary membranous nephropathy and their presence in some secondary nephropathies. The aim of this study is to describe the characteristics of the new antigens discovered and their association with other diseases.

Background: The burden of chronic kidney disease (CKD) is rising rapidly globally. Fluid overload (FO), an independent predictor of mortality in CKD, should be accurately assessed to guide estimation of the volume of fluid to be removed during haemodialysis (HD). Clinical score (CS) and bio-impedance analysis (BIA) have been utilized in assessment of FO and BIA has demonstrated reproducibility and accuracy in determination of fluid status in patients on HD. There is need to determine the performance of locally-developed CSs in fluid status assessment when evaluated against BIA.

Aim: To assess the hydration status of patients on maintenance HD using BIA and a CS, as well as to evaluate the performance of that CS against BIA in fluid status assessment.

Methods: This was a single-centre, hospital-based cross-sectional study which recruited adult patients with CKD who were on maintenance HD at Kenyatta National Hospital. The patients were aged 18 years and above and had been on maintenance HD for at least 3 mo. Those with pacemakers, metallic implants, or bilateral limbs amputations were excluded. Data on the patients' clinical history, physical examination, and chest radiograph findings were collected. BIA was performed on each of the study participants using the Quantum^® II bio-impedance analyser manufactured by RJL Systems together with the BC 4^® software. In evaluating the performance of the CS, BIA was considered as the gold standard test. A 2-by-2 table of the participants' fluid status at each of the CS values obtained compared to their paired BIA results was constructed (either ++, +-, -- or -+ for FO using the CS and BIA, respectively). The results from this 2-by-2 table were used to compute the sensitivity and specificity of the CS at the various reference points and subsequently plot a receiver operating characteristic (ROC) curve that was used to determine the best cut-off point. Those above and below the best CS cut-off point as determined by the ROC were classified as being positive and negative for FO, respectively. The proportions of participants diagnosed with FO by the CS and BIA, respectively, were computed and summarized in a 2-by-2 contingency table for comparison. McNemar's chi-squared test was used to assess any statistically significant difference in proportions of patients diagnosed as having FO by CS and BIA. Logistic regression analysis was conducted to assess whether the variables for the duration of dialysis, the number of missed dialysis sessions, advisement by health care professional on fluid or salt intake, actual fluid intake, the number of anti-hypertensives used, or body mass index were associated with a patient's odds of having FO as diagnosed by BIA.

Results: From 100 patients on maintenance HD screened for eligibility, 80 were recruited into this study. Seventy-one (88.75%) patients were fluid overloade

Chronic kidney disease (CKD) and hypertension (HTN) are closely associated with an overlapping and intermingled cause and effect relationship. Decline in renal functions are usually associated with a rise in blood pressure (BP), and prolonged elevations in BP hasten the progression of kidney function decline. Regulation of HTN by normalizing the BP in an individual, thereby slowing the progression of kidney disease and reducing the risk of cardiovascular disease, can be effectively achieved by the anti-hypertensive use of calcium channel blockers (CCBs). Use of dihydropyridine CCBs such as amlodipine (ALM) in patients with CKD is an attractive option not only for controlling BP but also for safely improving patient outcomes. Vast clinical experiences with its use as monotherapy and/or in combination with other anti-hypertensives in varied conditions have demonstrated its superior qualities in effectively managing HTN in patients with CKD with minimal adverse effects. In comparison to other counterparts, ALM displays robust reduction in risk of cardiovascular endpoints, particularly stroke, and in patients with renal impairment. ALM with its longer half-life displays effective BP control over 24-h, thereby reducing the progression of end-stage-renal disease. In conclusion, compared to other classes of CCBs, ALM is an attractive choice for effectively managing HTN in CKD patients and improving the overall quality of life.

Acute kidney injury (AKI) linked to coronavirus disease 2019 (COVID-19) has been identified in the course of the disease. AKI can be mild or severe and that is dependent on the presence of comorbidities and the severity of COVID-19. Among patients who had been hospitalized with COVID-19, some were admitted to intensive care unit. The etiology of AKI associated with COVID-19 is multifactorial. Prevention of severe AKI is the prime task in patients with COVID-19 that necessitates a battery of measurements and precautions in management. Patients with AKI who have needed dialysis are in an increased risk to develop chronic kidney disease (CKD) or a progression of their existing CKD. Kidney transplantation patients with COVID-19 are in need of special management to adjust the doses of immunosuppression drugs and corticosteroids to guard against graft rejection but not to suppress the immune system to place the patient at risk of developing a COVID-19 infection. Immunosuppression drugs and corticosteroids for patients who have had a kidney transplant has to be adjusted based on laboratory results and is individualized aiming at the protection of the transplanted from rejection.