Other Questions Flashcards
Sample transport Blood BM Solid tissues Amniotic fluid CVS
1-2days
ASAP after collection
ASAP; can be stored overnight at 4C but should never be fixed or frozen;
can use sterile tissue culture media or buffered saline solutions
ASAP
Should be transported in sterile medium containing an antibiotic and 5 to 10 percent fetal bovine serum if long term or delayed transport is required
What type of cells is the most useful for constitutional cytogenetic analysis ?
Lymphocytes stimulated with mitogen
(Ex:PHA- Down’s, Turner’s, Klinefelters.; unstimulated PB cultures are also useful in studying neoplastic cells in patients with leukemia or lymphoma who have circulating blast cells. B-cell neoplasms may require addition of a B-cell mitogen)
T cells ( thymus derived)
Respond to PHA mitogen and Concanavalin A
B-cells(BM derived)
Respond to LPS, Epstein-Barr virus and TPA
T & B cells
Pokeweed is a mitogen that can stimulate both
PUBS(percutaneous umbilical blood samples are obtained trans abdominals with the assistance of ultrasonography). They are most commonly requested in order to do a rapid karyotype.performed at 18 wks gestation the earliest.
Turnaround for amnio culture
7-14 days
Turnaround for fetal blood culture
2-3days
How many ccs of amniotic fluid should be collected?
15-30cc under sterile conditions, first 1-2 cc should be discarded to prevent MCC
Each specimen should be aspirated into 2 or 3 syringes( each from a different lot #) to minimize the chance of culture failures due to syringe toxicity. This also gives a backup in case of improper handling
Ideal gestational age for a specimen tap is 16-20 wks. Can be drawn as early as 12 wks and as late as 22 wks. Both are slow growing.
Solid tissue specimens
Skin biopsies, POCs
The most common problem with solid tissues
Microbial contamination
Specimen type: Peripheral blood stem cells
an alternative to the traditional bone marrow transplant
Because stem cells can also contain cancer cells, cytogenetic analysis can play a key role in determining if stem cells are relatively free of cancer cells prior to transplantation
Apheresis
process, by which Peripheral stem cells are harvested
In this procedure, blood is removed through a large vein in the arm and is run through a machine that removes stem cells. The rest of the blood is returned to the patient.