USMLE Prep - Medical Reference Library

IgA Nephropathy — Diagnosis & Treatment

System: Nephrology • Reviewed: Aug 31, 2025 • Step 1Step 2Step 3

Synopsis:

Risk‑stratify by proteinuria, eGFR, and MEST‑C pathology; maximize supportive care (RAASi, SGLT2i); consider immunosuppression in high‑risk cases.

Key Points

  • Stabilize ABCs; begin targeted evaluation without delaying life-saving therapy.
  • Use system-specific risk tools to guide testing and disposition.
  • Order high-yield tests first; escalate imaging when indicated.
  • Start evidence-based initial therapy and reassess frequently.

Algorithm

  1. Primary survey and vitals; IV access and monitors.
  2. Focused history/physical; identify red flags and likely etiologies.
  3. Order system-appropriate labs and imaging (see Investigations).
  4. Initiate guideline-based empiric therapy (see Pharmacology).
  5. Reassess response; arrange consultation and definitive management.

Clinical Synopsis & Reasoning

For Iga Nephropathy Diagnosis Treatment, frame the differential by acuity and pathophysiology, then align diagnostics to the leading hypotheses. Prioritize stabilization while obtaining high‑yield studies such as BMP (Renal/electrolytes), UA ± culture (Hematuria/proteinuria/infection), Renal ultrasound (selected) (Obstruction). Incorporate bedside imaging and targeted labs to define severity and identify complications; synthesize results with clinical trajectory to refine the working diagnosis and disposition needs.


Treatment Strategy & Disposition

Initiate disease‑directed therapy alongside supportive care, titrating to objective response. Pharmacologic options commonly include IV Fluids, Electrolyte repletion. Use validated frameworks (e.g., Risk Markers & Targets) to guide escalation and site of care. Address precipitating factors, de‑escalate empiric therapies with data, and arrange follow‑up for monitoring and risk‑factor modification; admit patients with instability, high risk of deterioration, or needs for close monitoring.


Management Notes

Use gastroprotective strategies if using high‑dose steroids. Shared decision‑making is key.


Epidemiology / Risk Factors

  • CKD/AKI, nephrotoxins; obstruction

Investigations

TestRole / RationaleTypical FindingsNotes
BMPRenal/electrolytesAKI/lyte changes
UA ± cultureHematuria/proteinuria/infectionFindings vary
Renal ultrasound (selected)ObstructionHydronephrosis

Risk Markers & Targets

MarkerGoal/Implication
Proteinuria<1 g/day, lower is better
BP<120–130 systolic individualized
MEST‑C lesionsPrognostic value
eGFR declineEscalate therapy if rapid
Anti‑PLA2RNot applicable (membranous marker)

Pharmacology

MedicationMechanismOnsetRole in TherapyLimitations
AcetaminophenAnalgesic/antipyreticHoursSymptom control as appropriateHepatotoxicity (overdose)
Ondansetron5-HT3 antagonismMinutesAntiemesis if neededQT prolongation

Prognosis / Complications

  • Reversibility by cause; electrolyte/volume complications

Patient Education / Counseling

  • Explain red flags and when to seek emergent care.
  • Reinforce medication adherence and follow-up plan.

References

  1. KDIGO IgA Nephropathy Guideline — Link