Myelodysplasia in fetus can be best diagnosed by
**Core Concept**
Myelodysplasia in the fetus refers to a group of disorders characterized by abnormal development of the bone marrow, leading to impaired hematopoiesis. This condition is often associated with an increased risk of congenital anemia, infections, and other hematologic abnormalities. The diagnosis of myelodysplasia in the fetus relies on a combination of clinical findings, laboratory tests, and imaging studies.
**Why the Correct Answer is Right**
The diagnosis of myelodysplasia in the fetus can be challenging due to the non-specific nature of the clinical presentation. However, ultrasound examination of the fetus can reveal characteristic findings such as rhizomelia, micrognathia, and increased nuchal translucency. The most definitive diagnosis is made by examining fetal blood samples obtained through cordocentesis, which shows abnormal morphology of red and white blood cells. This is often confirmed by molecular genetic testing, including FISH (fluorescence in situ hybridization) and PCR (polymerase chain reaction), to identify chromosomal abnormalities such as monosomy 7 or 5q deletion.
**Why Each Wrong Option is Incorrect**
**Option A:** Ultrasound examination alone is not sufficient for diagnosing myelodysplasia in the fetus, as it may reveal non-specific findings.
**Option B:** Fetal blood sampling is a key diagnostic tool, but it is not the only method used to diagnose myelodysplasia.
**Option C:** Molecular genetic testing is essential for confirming the diagnosis, but it is not the primary method of diagnosis.
**Clinical Pearl / High-Yield Fact**
The earliest sign of myelodysplasia in the fetus is often increased nuchal translucency, which can be detected as early as 10-14 weeks of gestation.
**Correct Answer: C. Fetal blood sampling and molecular genetic testing.**