From the Guidelines
Acute fatty liver of pregnancy (AFLP) is diagnosed using the Swansea criteria, which requires the presence of six or more of the following features in the absence of another explanation: vomiting, abdominal pain, polydipsia/polyuria, encephalopathy, elevated bilirubin (>0.8 mg/dL), hypoglycemia (<72 mg/dL), elevated uric acid (>5.7 mg/dL), leukocytosis (>11 × 10^6/L), ascites or bright liver on ultrasound, elevated transaminases (AST or ALT >42 IU/L), elevated ammonia (>42 IU/L), renal impairment (creatinine >1.7 mg/dL), coagulopathy (PT >14 seconds or partial thromboplastin time >34 seconds), and microvesicular steatosis on biopsy, as stated in the 2021 Hepatology study 1.
Key Features of AFLP
- Clinical presentation typically occurs in the third trimester with symptoms including nausea, vomiting, abdominal pain, jaundice, and signs of hepatic encephalopathy.
- Laboratory findings often show elevated liver enzymes, hyperbilirubinemia, thrombocytopenia, and coagulopathy.
- Liver biopsy showing microvesicular steatosis is the gold standard but rarely performed due to coagulopathy risks.
Differentiation from Other Conditions
- AFLP must be differentiated from other pregnancy-related liver conditions like HELLP syndrome and preeclampsia.
- The Swansea criteria have limitations in differentiating AFLP from other causes of liver diseases unique to pregnancy and acute liver failure of any cause, as noted in the 2024 Gastroenterology study 1.
Management
- Prompt diagnosis is crucial as management involves immediate delivery regardless of gestational age, along with supportive care to prevent maternal and fetal mortality.
- Liver transplantation evaluation should be considered in patients who progress to acute liver failure, especially those with suspected AFLP who have already given birth but do not improve clinically, as recommended in the 2024 Gastroenterology study 1.
From the Research
Diagnosis of Acute Fatty Liver of Pregnancy (AFLP)
The diagnosis of AFLP is supported by identifying 6 or more of the 15 Swansea criteria 2. The Swansea criteria include a range of clinical and laboratory findings, such as:
- Abdominal pain
- Vomiting
- Polydipsia/polyuria
- Encephalopathy
- Coagulopathy
- Hypoglycemia
- Hyperbilirubinemia
- Leukocytosis
- Ascites
- Acute kidney injury (AKI)
- Microvesicular steatosis on liver biopsy
- Elevated liver enzymes
- Hypofibrinogenemia
- Presence of fibrin split products
- Decreased antithrombin III
Clinical Features and Laboratory Results
The initial symptoms of AFLP can vary, but common presentations include:
- Nausea and vomiting 3, 4
- Abdominal pain 2, 5
- Jaundice 5
- Hypoglycemia 2, 5, 4
- Coagulopathy 2, 5, 3
- Acute kidney injury (AKI) 2, 3
- Elevated liver enzymes 5, 3
- Leukocytosis 2, 5
Diagnostic Challenges
Distinguishing AFLP from other high-risk liver diseases of pregnancy, such as HELLP and preeclampsia, can be challenging 6. The use of sensitive diagnostic tools, such as the Swansea criteria, can help support the diagnosis of AFLP 2. However, further work is needed to diagnose AFLP more quickly and accurately 6.