Nephrology
Astra Clinical Library
Nephrology
Practical nephrology guides for clinical decisions, with cited evidence, testing strategies, and actionable next steps.
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Nephrology
Chronic Kidney Disease
Chronic kidney disease requires persistent abnormalities in filtration or kidney-damage markers, risk stratification with eGFR and albuminuria, and early use of cardiorenal therapies while avoiding medication-related harm. Management intensity should reflect progression risk, cardiovascular risk, frailty, and patient goals.Nephrology
Hyperkalemia
The supplied sources do not contain clinical evidence on hyperkalemia diagnosis, electrocardiographic risk stratification, acute treatment, potassium-lowering therapies, dialysis, or longitudinal management; therefore, a safe point-of-care management review cannot be produced from this evidence set.Nephrology
Hyponatremia
A practical approach to confirm hypotonic hyponatremia, classify impaired water excretion using urine studies and volume assessment, treat neurologic emergencies with hypertonic saline, and prevent osmotic demyelination through controlled correction and urine-output surveillance.Nephrology
Nephritic Syndrome
Nephritic syndrome requires rapid separation of infection-related immune-complex disease from ANCA-associated, anti-GBM, complement-mediated, and monoclonal processes, with urgent biopsy and serologies when kidney function declines or pulmonary hemorrhage is suspected.Nephrology
Nephrotic Syndrome
Nephrotic syndrome requires rapid identification of thrombosis, acute kidney injury, infection, and an etiologic branch that determines biopsy, secondary-disease evaluation, supportive measures, and disease-specific immunosuppression.Nephrology
Infection-Related Glomerulonephritis
Infection-related glomerulonephritis requires prompt recognition of a nephritic urine sediment, identification and eradication of active infection, volume and blood-pressure control, and kidney biopsy when rapidly progressive injury or competing immune glomerular disease would change treatment.Nephrology
Anion Gap Metabolic Acidosis
Use blood gas confirmation, anion-gap classification, potassium, kidney function, and urinary ammonium surrogates to rapidly distinguish life-threatening organic acid accumulation from gastrointestinal bicarbonate loss, renal tubular acidosis, chronic kidney disease, and chloride-related acidosis.Nephrology
Rapidly Progressive Glomerulonephritis
Rapidly progressive glomerulonephritis requires urgent confirmation of glomerular injury, parallel serologic classification, kidney biopsy, and cause-specific therapy before potentially irreversible crescentic injury progresses to kidney failure or pulmonary hemorrhage.Nephrology
Prerenal Kidney Failure
Prerenal kidney failure requires rapid separation of reversible renal hypoperfusion from acute tubular injury, obstruction, and congestive cardiorenal physiology. Use trajectory, volume assessment, urine studies, medication review, targeted fluid challenge, and serial creatinine and urine output to restore perfusion without causing harmful fluid accumulation.Nephrology
Alport Syndrome
Confirm suspected Alport syndrome with COL4A3, COL4A4, and COL4A5 testing, define inheritance and renal risk, initiate renin-angiotensin system blockade when indicated, and identify relatives requiring surveillance before proteinuria and progressive kidney dysfunction develop.Cardiology and Nephrology
Cardiorenal Syndrome
Cardiorenal syndrome requires phenotype-based management: distinguish congestion from hypoperfusion, establish whether cardiac, renal, or systemic disease is primary, and pursue decongestion without reflexively abandoning therapy for a creatinine rise.Nephrology
End-Stage Renal Disease
Manage kidney failure by identifying emergent dialysis indications, separating chronic uremic symptoms from reversible mimics, preparing renal replacement options before crisis, and initiating dialysis for refractory clinical complications rather than an isolated eGFR threshold.Nephrology
Hemolytic Uremic Syndrome
Hemolytic uremic syndrome is a thrombotic microangiopathy requiring immediate confirmation of hemolysis and kidney injury, exclusion of severe ADAMTS13 deficiency and Shiga toxin infection, identification of secondary triggers, and rapid complement-directed treatment when complement-mediated disease remains likely.Nephrology
Minimal Change Disease
Adult minimal change disease requires kidney-biopsy confirmation, exclusion of secondary drivers, prompt management of nephrotic complications, and a prolonged glucocorticoid course. Relapse pattern, steroid toxicity, and kidney function determine whether cyclophosphamide, calcineurin inhibition, or other steroid-sparing therapy is appropriate.Nephrology
Goodpasture Syndrome
Treat suspected Goodpasture syndrome as a pulmonary-renal emergency: stabilize hypoxemia and kidney failure, obtain anti-GBM and ANCA serologies urgently, pursue kidney biopsy when feasible, and initiate antibody removal plus immunosuppression promptly when clinical probability is high.Nephrology
Acute Kidney Injury Medication Adjustment
In acute kidney injury, promptly reconcile medications, stop or reassess reversible nephrotoxins, adjust renally cleared drugs to changing kidney function, preserve essential therapy when benefits outweigh risk, and monitor creatinine, urine output, volume status, and drug concentrations when exposure is unpredictable.Nephrology
Prerenal Azotemia Versus Acute Tubular Injury
Differentiate reversible renal hypoperfusion from tubular injury by integrating exposure history, volume assessment, urine microscopy, urine indices, obstruction testing, and trajectory after hemodynamic correction. Treat life-threatening electrolyte, acid-base, uremic, and volume complications before waiting for diagnostic certainty.Nephrology
Acute Interstitial Nephritis
Approach suspected acute interstitial nephritis as unexplained acute kidney injury: stop plausible culprit drugs, exclude obstructive, ischemic, infectious, and glomerular processes, and use kidney biopsy when the diagnosis or immunosuppression decision remains consequential.Nephrology
CKD Albuminuria Treatment
Confirm persistent albuminuria with quantitative UACR, stage risk jointly with eGFR, maximize single-agent renin-angiotensin blockade, and layer SGLT2 inhibition and finerenone selectively in type 2 diabetes while monitoring potassium and kidney function.Nephrology
Metabolic Acidosis Anion Gap Interpretation
Interpret metabolic acidosis by confirming the primary process, calculating the serum anion gap consistently, and using gap pattern, targeted metabolites, urine indices, and exposure history to rapidly separate ketoacidosis, lactic acidosis, renal failure, toxic ingestion, and bicarbonate loss.Nephrology
Non-Anion Gap Metabolic Acidosis
A practical workup for hyperchloremic metabolic acidosis: confirm the acid-base disorder, identify gastrointestinal versus renal bicarbonate loss, use potassium and urinary ammonium surrogates appropriately, and recognize renal tubular acidosis, kidney dysfunction, urinary diversion, and chloride-rich fluid exposure.Nephrology
Hypernatremia Free Water Replacement
A volume-status and duration-based approach to calculate free water deficit, select enteral or intravenous replacement, protect perfusion first, account for ongoing losses, and titrate serum sodium monitoring to avoid both undercorrection and unsafe overcorrection.Nephrology
Hypomagnesemia Replacement
Choose intravenous magnesium for severe or symptomatic deficiency, correct concurrent potassium and calcium resistance, then distinguish gastrointestinal from renal losses to prevent recurrence. Replacement must be adjusted for kidney function, ongoing losses, infusion toxicity, and culprit medications.Nephrology
Diabetes Medication Selection in CKD
Select glucose-lowering therapy in type 2 diabetes and chronic kidney disease by prioritizing SGLT2 inhibitors for kidney and heart failure protection, adding GLP-1 receptor agonists for cardiovascular and glycemic benefit, and considering finerenone for albuminuric disease with potassium surveillance.Nephrology and Hospital Medicine
Hyponatremia Correction Limits
For symptomatic hyponatremia, achieve an early 4-6 mEq/L sodium rise to reverse cerebral edema, then limit further correction according to chronicity and osmotic demyelination risk. Unknown duration should be managed as chronic, with frequent sodium measurements and prompt relowering after excess correction.Nephrology and Critical Care Medicine
Hyponatremia Overcorrection Management
Prevent osmotic demyelination by identifying patients at greatest risk, tracking sodium trajectory and urine output during active correction, arresting water diuresis with desmopressin, and promptly relowering sodium with electrolyte-free water when correction limits are exceeded.Nephrology
Urine Studies in Hyponatremia
Use urine osmolality and spot urine sodium, obtained before therapy when feasible, to separate suppressed vasopressin states from antidiuretic water retention and to distinguish renal salt loss, extrarenal loss, SIAD, and low effective arterial volume.Emergency Medicine and Nephrology
Hyperkalemia Emergency Treatment
Treat hyperkalemia as an electrical emergency when potassium exceeds 6.0 mmol/L or ECG toxicity is present: monitor, stabilize myocardium with IV calcium, shift potassium intracellularly, remove total-body potassium, and reassess for rebound or dialysis need.Nephrology
AKI Urine Microscopy
Urine microscopy is most useful in acute kidney injury when urinalysis suggests an active sediment or the clinical course is unexplained. Freshly examined sediment can redirect evaluation toward acute tubular injury, glomerulonephritis, vasculitis, crystal nephropathy, or biopsy-confirmable interstitial disease.Nephrology and Critical Care Medicine
Dialysis Indications in Acute Kidney Injury
Initiate kidney replacement therapy urgently for refractory electrolyte, acid-base, fluid, or uremic complications—not creatinine alone. In severe ICU-associated AKI without an emergency indication, structured surveillance and standard initiation avoid unnecessary dialysis without improving survival through accelerated treatment.Nephrology
Nephritic Syndrome Workup
Evaluate suspected nephritic syndrome by confirming glomerular hematuria, quantifying kidney injury and proteinuria, identifying immediately reversible threats, then using complement and targeted serologies to direct urgent kidney biopsy and cause-specific management.Nephrology
Nephrotic Syndrome Biopsy Indications
Kidney biopsy is usually required for unexplained adult nephrotic syndrome, but selected patients with PLA2R-positive membranous nephropathy may avoid it. In children, steroid response, age, atypical features, genetic risk, and failure to remit determine whether biopsy changes management.Nephrology