R.S.V.P.

What should we do if tissue culture media cannot be located or if the tissue culture media is "expired"?

If media is not available, samples can be placed in maternal serum. (Draw 7-10 cc of maternal blood in a sterile tube, spin it down and use the plasma or serum as transport media.) If a maternal blood sample cannot be obtained, sterile saline can be used.

Culture media, if kept frozen, will be usable for about 1 year. If "expired" media is available, it is still preferable to the use of sterile saline or maternal serum.

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We have had several reports returned to us that indicate the sample was contaminated and it is not possible to obtain a result. Are we doing something wrong in our sampling technique?

Not necessarily. Birth does not occur in a sterile environment, and despite best efforts bacterial overgrowth will occur. There are, however, several suggestions that will make such contamination less likely:

•Clean the site to be sampled with sterile saline or with alcohol; if alcohol is used make sure it is completely dried before biopsy. (Do not use iodinated agents, such as Betadine—they markedly inhibit cell growth.)

•Wear sterile gloves.

•Rinse samples in sterile saline before placing in culture media.

•Do not take oversize samples and "pack" them into the small culture vials. Having to pry the samples from the vials increases the opportunity for contamination. 1 cm2 samples are more than sufficient for cytogenetic purposes.

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How and when are the cytogenetics results relayed?

While the cytogenetic result will be reported in the WiSSP summary letter, which is only completed after the results of all investigations are received by our office, the laboratory will issue their own report when their analysis is complete. On average, a result from the lab will be available in 4-6 weeks. They will send a report to the physician(s) listed on the Cytogenetics Request sheet. Those individuals listed on the WiSSP summary sheet will only receive a copy of the written WiSSP review. Those individuals on the Cytogenetics Request form will be sent a copy of the chromosome result only. It is important that names and addresses of individuals to whom each report should be sent be included on the appropriate requests.