Related Experiment Videos
Periodic acid Schiff (PAS) positivity in fetal erythroblasts
1Istituto di Scienze Biomediche, Università, Milano, Ospedale San Paolo, Italy.
Abstract:
The smears of 26 fetal blood samples taken for prenatal diagnosis were stained for the PAS reaction. Twelve out of 26 cases were subsequently found to be normal and 14 were found to be affected by different abnormalities; 83.4% of normal cases and 92.8% of abnormal cases showed moderate positivity to the PAS reaction. A higher percentage of PAS positive erythroblasts was found in the abnormal cases (p less than 0.01). Five cases with a percentage greater than 10% also showed a very high percentage of erythroblasts. No linear correlation was found between PAS positivity and erythroblastosis either in the normal or the abnormal cases, but pooling them resulted in a correlation between PAS positivity and erythroblastosis (r = 0.536; p less than 0.005). PAS positivity was most often diffuse and scored 1+. Since erythroblastosis is considered an indirect sign of fetal liver erythropoiesis, the hepatic environment and its peculiar hemopoiesis could play a role in producing a cohort of PAS positive erythroblasts.
Insights
Prenatal diagnosis using the PAS reaction on fetal blood smears revealed higher PAS-positive erythroblasts in abnormal cases. This suggests a link between fetal liver erythropoiesis and PAS positivity in erythroblasts.
Area of Science:
- Perinatology
- Hematology
- Biochemistry
Background:
- Prenatal diagnosis relies on accurate fetal assessments.
- Erythroblastosis, an increase in immature red blood cells, can indicate fetal distress or abnormalities.
- Periodic acid-Schiff (PAS) staining is a histochemical technique used to detect carbohydrates.
Purpose of the Study:
- To investigate the correlation between PAS positivity in fetal blood erythroblasts and fetal abnormalities detected during prenatal diagnosis.
- To explore the potential role of fetal liver erythropoiesis in PAS positivity.
Main Methods:
- Fetal blood samples (n=26) from prenatal diagnoses were stained using the PAS reaction.
- Samples were categorized as normal (n=12) or abnormal (n=14).
- PAS positivity and erythroblast percentage were quantified and analyzed.
Main Results:
- A high percentage of both normal (83.4%) and abnormal (92.8%) cases showed moderate PAS positivity.
- Abnormal cases exhibited a significantly higher percentage of PAS-positive erythroblasts (p<0.01).
- A moderate positive correlation was found between PAS positivity and erythroblastosis when all cases were pooled (r=0.536, p<0.005).
Conclusions:
- Increased PAS-positive erythroblasts in fetal blood are associated with fetal abnormalities.
- The findings suggest that the fetal hepatic environment and its erythropoiesis may contribute to PAS-positive erythroblasts.
- PAS staining of fetal erythroblasts may serve as a potential biomarker in prenatal diagnosis.