American Society for Clinical Pathology (ASCP) Technologist in Cytogenetics certification (ASCP CG) Practice Test

What action should be taken when a single dish from amniotic fluid turns cloudy after 24 hours of culture initiation?

1. Dispose of all dishes

2. Dispose of the cloudy dish only

3. Subculture the cloudy dish

4. Keep all dishes for further analysis

The correct answer is: Dispose of the cloudy dish only

The appropriate action when a single dish from amniotic fluid turns cloudy after 24 hours of culture initiation is to dispose of the cloudy dish only. Cloudiness in a culture dish typically indicates contamination or an overgrowth of non-cytogenetically relevant cell types, which can compromise the integrity of the results and lead to inaccurate interpretation of the genetic material. Disposing of just the cloudy dish allows for the remaining cultures—which could be viable and uncontaminated—to be preserved for analysis. This targeted approach ensures that valuable data from potentially healthy cultures are not inadvertently discarded due to one problematic dish. Keeping all dishes or disposing of all dishes would unnecessarily discard potentially useful information, while subculturing the cloudy dish could risk spreading contamination to other cultures. Thus, it is best practice to dispose of the contaminated dish alone and continue monitoring the others that remain clear.