II. Epidemiology
- Rare event
III. Pathophysiology
- Arterial thromboembolic event resulting in Occlusion of the renal artery or its segmental branches
IV. Risk Factors: Arterial Embolism Risk
- Case study based associations
- Atrial Fibrillation (65%)
- Hypertension (53%)
- Ischemic Heart Disease (41%)
- Prior Thromboembolic Events (35%)
- Mitral Stenosis (35%)
- Domanovitis (1999) Medicine 78(6): 386-94 [PubMed]
- Other Risk Factors
- Tobacco Abuse
- Hypercoagulable State
- Connective Tissue Disorders
- Vasculitis
- Atherosclerotic vascular disease involving the aorta or renal arteries
- Angiography (dislodged atherosclerotic Plaque)
- Endocarditis
- Abdominal Aortic Aneurysm
- Abdominal or flank Trauma
V. Symptoms
- Sudden, Severe Flank Pain
- Nausea and Vomiting
- Gross Hematuria
VI. Differential Diagnosis
- See Flank Pain
- See Hematuria Causes
-
Ureteral Stone
- Renal Infarct diagnosis is frequently delayed due to misdiagnosis as Ureteral Stone
- Perform CT imaging with IV contrast to evaluated for broader differential in higher risk patients (see below)
VII. Labs
- Comprehensive Metabolic Panel
- Increased Serum Creatinine may be present
-
Lactate Dehydrogenase (LDH)
- May be increased
-
Urinalysis
- Gross or Microscopic Hematuria
- Proteinuria may be present
VIII. Imaging
-
CT Abdomen and Pelvis with IV Contrast
- With IV contrast, infarcted renal Medulla will fail to enhance compared with the surrounding cortex
- Infarcts are best seen when imaged at 25 to 70 seconds after contrast (typical CT portal venous phase)
- Flank Pain is often imaged without contrast (for Ureterolithiasis), which will typically miss Renal Infarcts
- Use IV contrast for CT, when broader differential is pursued (esp. in patients at risk for Thromboembolism)
- IV contrast does not diminish CT Test Sensitivity for Clinically SignificantUreteral Stones
- Dym (2014) Abdom Imaging 39(3): 526-32 [PubMed]
- With IV contrast, infarcted renal Medulla will fail to enhance compared with the surrounding cortex
IX. References
- Broder (2023) Crit Dec Emerg Med 37(12): 20-1
- Mulayamkuzhiyil (2023) Renal Infarction, StatPearls, +PMID: 35881744 [PubMed]