Management of Acute Kidney Injury in Pregnancy
Manage pregnancy-related AKI by identifying the underlying obstetric cause based on gestational timing, initiating dialysis using the same urgent criteria as non-pregnant patients (but consider earlier initiation with high urea levels), and delivering the fetus when severe AKI threatens maternal or fetal survival. 1
Diagnostic Approach by Gestational Period
The traditional prerenal/renal/postrenal classification is less useful in pregnancy. Instead, approach PR-AKI by gestational timing 1:
First Trimester
- Hyperemesis gravidarum is the most common cause 2
- Septic abortion (particularly in low-resource settings) 1
Late Pregnancy/Postpartum
- Preeclampsia is the leading cause in high-resource settings (44% of cases) 1, 3
- Hemorrhage (28% of cases) 3
- Thrombotic microangiopathies (TTP, atypical HUS, HELLP syndrome)
- Acute fatty liver of pregnancy
- Sepsis (14% of cases, more common in low-resource settings) 1, 3
Critical Diagnostic Consideration
Distinguish AKI from undiagnosed CKD, especially in women without prepregnancy screening—many initially labeled as PR-AKI actually have underlying CKD and remain dialysis-dependent postpartum 1. Up to 20% of preeclampsia cases occur on a background of undiagnosed CKD 1.
Biomarkers and Staging
- Standard AKI biomarkers are not validated in pregnancy 1
- PlGF and sFlt-1 can help rule out preeclampsia as the cause of creatinine elevation (when available) 1
- RIFLE and AKIN staging systems predict mortality and CKD risk, though not pregnancy-specific 1
Treatment Algorithm
1. Cause-Specific Management
Target the underlying obstetric condition:
- Preeclampsia/HELLP/Acute fatty liver: Prompt delivery 2
- TTP: Plasmapheresis 2
- Atypical HUS: Eculizumab 2
- Glomerulonephritis: Steroids and immunosuppression 2
2. Dialysis Initiation
Use the same urgent criteria as non-pregnant patients (hyperkalemia, severe acidosis, uremic complications, refractory volume overload) 1
Key modification: Consider earlier dialysis initiation when:
- High urea levels are present 1
- PR-AKI is superimposed on CKD 1
- Rationale: Late dialysis start is associated with poor maternal and fetal prognosis 1
Outcomes with RRT: Among 1,673 pregnant women requiring dialysis, maternal survival was excellent (15 deaths total), with fetal survival of 74% on hemodialysis and 40% on peritoneal dialysis 4. Timely RRT initiation achieves complete renal recovery in 74% of cases 3.
3. Supportive Management
- Antihypertensives: Several agents are safe in pregnancy 1
- Loop diuretics: Use for volume overload control and to reduce antihypertensive burden 1
4. Delivery Timing
Severe AKI is an indication for delivery or pregnancy interruption, based on:
- Maternal status
- Fetal status
- Gestational age 1
Early delivery is typically by Caesarean section 1
Critical Pitfalls
Medication-Induced AKI
Antibiotics and tranexamic acid used for delivery complications can cause AKI or cortical necrosis 1—monitor renal function closely when using these agents.
Multidisciplinary Care
Management requires coordination between nephrologist, obstetrician, and neonatologist 2. Lack of obstetric nephrology training is a major barrier to optimal outcomes 1.
Postpartum Follow-Up
After PR-AKI or preeclampsia, patients require regular long-term follow-up due to increased risk of:
- Incident CKD and kidney failure 1
- Cardiovascular disease 1
- Recurrent complications in future pregnancies 1
At 3-6 months postpartum, perform comprehensive evaluation including:
- Serum creatinine
- Kidney ultrasound
- Blood and urinary electrolytes
- Assessment for persistent proteinuria/hypertension 1
Annual medical reviews for 5-10 years are advised, with blood pressure target <120/80 mmHg 1.