World Kidney Day 2023 – Kidney Health for All
Preparing for the unexpected, supporting the vulnerable!
From the Editors’s Desk!
Nephrology for Nurses! – Part 2
The NIGHTINGALE presents TWELVE abstracts on major papers being published on the occasion in the journal MEDICINE, from Elsevier UK
(1). Renal stone disease. Lancet 2023;51:P229-233.
Abstract
Renal stone disease (urolithiasis, nephrolithiasis) covers many conditions causing kidney, ureteric or bladder stones. These include metabolic and inherited disorders, anatomical defects of the upper or lower urinary tract, and chronic urinary infection. However, most cases of renal stones are idiopathic. They present with loin or abdominal pain, and visible or non-visible haematuria; this is followed by the eventual passage of a stone and resolution, or the need for further investigation and intervention. Renal stones often recur, and it is important to identify the underlying cause, particularly because the risk can be related to diet and lifestyle, and is often associated with hypertension and/or diabetes mellitus. Although clinical management is largely surgical and can seem straightforward, the increasing prevalence of renal stone disease in developed countries is becoming a significant health and economic burden.
(2). Initial management of lower urinary tract symptoms and bladder outlet obstruction. Lancet 2023;51:P234-238.
Lower urinary tract symptoms (LUTS) are a common presenting complaint for both men and women, affecting >60% of men and women aged >40 years. They encompass a wide range of aetiologies and can be an indicator of covert unerlying pathologies such as obesity and metabolic syndrome. The initial assessment should focus on identifying the underlying cause and assessing the impact on quality of life aided by validated objective questionnaires. Risk factors have been identified that can predict the likelihood of progression of LUTS (e.g. urinary retention), such as age, moderately elevated prostate-specific antigen and prostate size. Initial management includes conservative and medical management, and not all patients require surgery. Identifying those at high risk of acute urinary retention helps in counselling and subsequent management decisions. Aside from lifestyle modification, medications include selective α-adrenoceptor blockers, 5α-reductase inhibitors, antimuscarinics, β3-agonists and phosphodiesterase-5 inhibitors, either as monotherapy or combination therapy.
(3). Urinary tract infection. Lancet 2023;51:p229-304.
Urinary tract infection is one of the most common infections affecting humans. Uncomplicated infections most commonly occur in otherwise healthy women when uropathogenic bacteria, usually Escherichia coli, enter the bladder and overcome the host’s innate immunity. Complicated infections occur in individuals with an anatomical or functional abnormality of the urinary tract. Diagnosis is made on the basis of symptoms, and diagnostic precision is improved by urinalysis. Urine culture is important in individuals with severe, recurrent or complicated infection and when the diagnosis is uncertain, for example in children and elderly people. Most women with symptoms that resolve quickly do not require further investigation, but imaging of the renal tract, functional testing and cystoscopy should be considered in children, men and patients with recurrent or severe infection. Empirical antibiotic treatment started on the basis of symptoms and directed by urinalysis is suitable for uncomplicated cystitis but should be altered based on culture results for more severe infections. Three days of antibiotic treatment is usually sufficient for uncomplicated cystitis in women. Long-term or post-coital antibiotics are effective for patients with recurrent infection.
(4). Primary glomerular disease. Lancet 2023;51:P244-251.
This is a review of the clinical features, pathogenesis, investigation and management of glomerulonephritis (GN). GN can occur as a primary isolated renal disease, as a manifestation of systemic diseases such as vasculitis or lupus, or secondary to drugs, infections or tumours. It is an important cause of morbidity and mortality and a potentially preventable cause of end-stage renal disease; early diagnosis is vital to allow timely referral to specialist units where renal biopsy can be performed. Proteinuria and/or haematuria are typical findings. Pathogenesis involves immune cells and inflammatory mediators, with intrinsic glomerular cells, especially podocytes, also being important in glomerular injury and the responses to it. I present brief outlines of schemes for appropriate investigations when GN is suspected, and guidelines for referral strategies to investigate proteinuria and haematuria, and manage common forms of GN. When nephrotic syndrome (NS) is present, it can lead to major morbidity and potential mortality even if excretory renal function is well preserved. NS should be managed, irrespective of the cause, with diuretics, antiproteinuric agents, cholesterol-lowering agents and sometimes anticoagulants. Treatment with corticosteroids, with or without other immunosuppressive agents, is effective in many forms of GN, but adverse effects are problematic. More selective forms of immunotherapy are increasingly used as understanding of the pathogenesis of GN improves but there is a continuing need for better collaboration on clinical trials so that the evidence base can be improved.
(5). Secondary glomerular disease. Lancet 2023;51:P252-257.
Secondary glomerular diseases are those with an identifiable underlying or systemic cause, in contrast to primary diseases, where a localized or intrinsic renal pathology is present. Diabetic and hypertensive glomerulopathies are the most common forms of secondary glomerular disease, although a kidney biopsy is not usually required for their diagnosis or management. Biopsy is more commonly required in cases of suspected glomerulonephritis, where a variety of histological lesions can be seen, all of which – including podocytopathy, membranous nephropathy and various forms of proliferative glomerulonephritis – have established secondary causes or associations. These include: infections, the most common cause of secondary glomerulonephritis worldwide; autoimmune and rheumatic diseases, such as systemic lupus erythematosus and small vessel vasculitis; drugs, which can injure the glomerulus directly or via induction of autoimmune diseases; and cancers, including solid tumours and haematological malignancies. Where secondary causes are identified, the goals of treatment are generally to remove the offending trigger, with or without anti-inflammatory or immunosuppressive treatment directed at the renal pathology.
(6). Tubulo-interstitial disorders. Lancet 2023;51:P258-261.
The diagnosis of tubulo-interstitial nephritis is increasing worldwide in parallel with access to healthcare, changing prescribing habits and socio-ecological changes. The histopathological differentiation of acute and chronic tubulo-interstitial nephritis is necessary to better understand the epidemiology, presentation and clinical management of the underlying aetiologies. This review endeavours to provide a clinical update on the diagnosis and management of acute and chronic tubulo-interstitial nephritis.
(7). Identification and management of diabetic nephropathy. Lancet 2023;51:P262-268.
Diabetic kidney disease is the leading cause of end-stage kidney disease in developed countries. It accounts for up to 40% of patients requiring renal replacement therapy. Optimum glycaemic and blood pressure control are currently the only strategies that have shown benefits in both preventing and attenuating the progression of diabetic renal disease. However, recent discoveries of several underlying mechanisms have led to the discovery of novel promising therapeutic agents that have proved to be very effective in several outcomes studies. In particular clinical trials, new antihyperglycaemic agents have demonstrated very promising results, independent of glucose control.
(8). Thrombotic microangiopathies and the kidney. Lancet 2023;51:P269-272.
Thrombotic microangiopathies are rare but carry a high morbidity and mortality. Most are treatable if identified early. A high index of suspicion is required in individuals presenting with renal impairment and features of microangiopathy such as a low platelet count and Coombs test-negative haemolytic anaemia. In Shiga toxin-mediated haemolytic-uraemic syndrome, bacteria such as Escherichia coli O157 and O104 adhere to the intestinal mucosa and secrete a highly potent Shiga cytotoxin that binds to the glomerular endothelium and causes an endotheliopathy. In atypical haemolytic-uraemic syndrome, the alternative pathway of complement, in the absence of an intact regulatory system, runs out of control. The endothelium is the predominant target in a variety of organs including the kidneys, brain and heart. In thrombotic thrombocytopenic purpura, dysfunction of the ADAMTS13 enzyme that cleaves and inactivates ultralarge multimers of von Willebrand factor leads to the formation of platelet-rich thrombi.
(9). Paraprotein-related renal disease. 2023;51:273-279
Paraprotein-related renal disease encompasses a group of rare diseases characterized by distinct renal injury caused by the direct or indirect effects of a nephrotoxic paraprotein. Individuals can present with proteinuric renal impairment or, more rarely, tubular dysfunction. Diagnosis is often challenging because of the wide range of disease manifestations, difficulties with detection of the pathogenic clone and the common finding of an incidental paraprotein in elderly individuals. The combination of a renal biopsy along with a full haematological work-up is required to link a paraprotein to kidney disease. Chemotherapy directed at the plasma cell clone can halt the production of the paraprotein, which can in turn benefit renal function. Early diagnosis and the use of rapidly effective chemotherapy agents have improved patient and renal outcomes for these disorders.
(10). Lupus nephropathy and vasculitis. 2023;47:672-678.
Multisystem autoimmune diseases, including systemic lupus erythematosus (SLE) and vasculitis, are inflammatory conditions of unknown cause. Renal involvement occurs in a variety of forms and usually represents a severe disease manifestation. SLE is complicated by renal involvement (lupus nephritis) in over one-third of individuals. Small vessel vasculitides, including antineutrophil cytoplasmic antibody-associated vasculitis, also frequently affect the kidneys, causing a rapidly progressive glomerulonephritis. Histologically, this manifests as a necrotizing, crescentic glomerulonephritis. This is potentially reversible but if left untreated generally results in end-stage renal failure and death within days to weeks. A crescentic glomerulonephritis can also be seen in SLE, but this is not the typical pattern of lupus nephritis, which is usually characterized by immune complex deposition causing a diffuse, proliferative glomerulonephritis. Lupus nephritis and renal vasculitis are the most frequent causes of renal failure in multisystem autoimmune disease.
(11). Renal dysfunction in liver disease. 2023;51:288-292.
Acute kidney injury is a frequently encountered complication in individuals with chronic liver disease. As in the general population, pre-renal, intrinsic and post-renal causes should be considered, with particular consideration given to sepsis and gastrointestinal bleeding. Hepatorenal syndrome (HRS) is a particular phenotype of acute kidney injury found in patients with decompensated cirrhosis and ascites, the diagnosis of which should be made only after excluding other causes. Acute and chronic renal dysfunction in cirrhosis is common, and both confer a negative impact on morbidity and mortality. As such, it is essential for all clinicians involved in the care of these individuals to be able to identify them in both inpatient and outpatient settings, so that appropriate management strategies can be promptly implemented. This article reviews the aetiology and management of renal dysfunction in individuals with chronic liver disease. HRS has a high morbidity and mortality, and its pathogenesis, diagnosis and specific management are highlighted here.
(12). Renal disease in pregnancy. Medicine 2023;51:293-299.
The diagnosis of acute kidney injury (AKI) in pregnancy is complicated by haemodynamic and urinary tract changes in pregnancy, and non-pregnant references intervals for serum creatinine should not be used. Pre-eclampsia is the most common cause of AKI in pregnancy. Although pregnancy-associated haemolytic microangiopathies are rare, it is useful for physicians and nephrologists to be aware of potential clinical discriminators as different, timely management is required. Pregnancy is successful for most women and pregnant individuals with chronic kidney disease (CKD). There is, however, an increased risk of adverse parental and neonatal outcomes at all stages of CKD, including pre-eclampsia, growth restriction, preterm delivery, low birthweight, neonatal unit admission and postpartum loss of parental kidney function. Pregnant persons with CKD should therefore have access to pre-pregnancy counselling to be able to make an informed decision about proceeding with pregnancy. A multidisciplinary team with expertise in obstetric nephrology should coordinate the care of pregnant individuals with CKD, which includes obstetric and kidney disease surveillance, monitoring of immunosuppression, and the initiation and/or intensification of haemodialysis if required. The diagnosis of superimposed pre-eclampsia remains clinically challenging.