Fetal liver calcifications are found in 1 in 1700 (0.05%) pregnancies.
One-third is isolated, while two-thirds are associated with other fetal abnormalities.
Following the diagnosis of calcifications on the surface of the fetal liver, it is important to rule out meconium peritonitis.
Differential diagnosis includes infection, liver tumors, vascular calcification, and fetal aneuploidy
Management should include detailed fetal anatomical scan to look for associated anomalies, maternal TORCH titers, amniocentesis for karyotype and CMV culture, and fetal MRI if an intrinsic hepatic mass is suspected.
Prognosis depends on presence or absence of associated abnormalities.
If a detailed work-up is unremarkable, the fetal prognosis is excellent.
Fetal hepatic calcifications can be divided into three main categories: peritoneal, parenchymal, and vascular. Peritoneal hepatic calcifications present as calcified masses on the surface of the fetal liver. Most commonly, this is due to meconium peritonitis resulting from in utero bowel rupture. Meconium peritonitis is the most common cause of fetal abdominal calcifications (Lince et al., 1985) (see Chapter 70). Parenchymal calcifications are due to the presence of intrauterine infection or tumor. Fetal tumors may be primary in the liver or metastatic, presenting as a complex mass with areas of increased echogenicity and possible shadowing. Fetal tumors encompass both benign and malignant varieties, including hemangioendotheliomas, hamartomas, and hepatoblastomas. Parenchymal calcifications appear as scattered nodules, with or without additional evidence of other affected organs. The most common in utero infections that can cause fetal liver calcifications include varicella and the TORCH agents (Figure 69-1). Hepatic calcifications due to vascular abnormalities result from calcified portal or hepatic venous clots, which are due to hypoperfusion or thromboembolism (Nguyen and Leonard, 1986; Bronshtein and Blazer, 1995).
Transverse scan through the abdomen of a fetus with varicella infection demonstrating multiple areas of intraparenchymal calcification. (Reprinted, with permission, from Drose JA, Dennis MA, Thickman D. Infection in utero: US findings in 19 cases. Radiology. 1991;178:369-374.)
With the increased utilization of prenatal sonographic screening, fetal hepatic calcifications are detected prenatally more frequently than they are observed in newborn infants. In one study, evidence of hepatic calcifications was noted in 14 of 24,600 fetuses, an incidence of approximately 1 in 1700 (0.05%) of screened fetuses, (Bronshtein and Blazer, 1995). In a population of 1500 spontaneously aborted fetuses, 33 were demonstrated to have hepatic calcification, an incidence of 2.2% in this abnormal patient population (Hawass et al., 1990). In the 33 affected fetuses, 17 hepatic calcifications were found in the first trimester and 16 in the second trimester.
Fetal liver calcifications can be detected reliably by the beginning of the second trimester of pregnancy (Figure 69-2). ...