We worked up a type discrepancy for a serivce hospital that forwards as an A and came up w+ on reverse A1 and A2. It turned out to be rouleaux and was resolved with saline replacement. As part of the type, we ran an Rh that was 2+ and the control was negative. We reported A pos. 2 days later the hospital reported they had a historical A neg for the patient (which was never shared with us at any point previously). Of couse, now none of the original results can be duplicated including the rouleaux. Has anyone seen plasma proteins interfering with the Rh like this? Any suggestions on how to approach in the future, aside from making the hospital provide ALL relevent information?