—Drs McClellan and Morse suggest a valid alternative method for preparing a streptokinase 100 IU skin test dose. If their dilution protocol were carried out efficiently, it should not delay streptokinase administration significantly. Only occasionally would a prepared streptokinase therapeutic dose need to be discarded because of a positive skin test, so the cost of their protocol would be minimal.
In consideration of the costs of maintaining stock streptokinase solutions for skin testing, we have previously changed the frequency of preparing testing solutions in our hospital from every two to four weeks. By enzymelinked immunosorbent assay (ELISA) measurements, we have found that the antigenic potency of these streptokinase solutions is retained for at least two months.
Because antistreptokinase serum titers increase significantly after streptokinase administration (reaching peak titers ten to 21 days after exposure),1-3 it has been stated that recent streptokinase administration (within three days to three to six