EMDIS message: ALM_REQ

This message can be considered as an extension to the PAT_UPD message. The result is of ALM_RES messages with fully matched donors with regards to the alternative phenotype - therefore providing a simple mechanism to obtain mismatched donors for the patient. It also provides cord blood units with up to two major antigen mismatches (as usual) with regards to the phenotype given if P_MAX_DON_CB is greater than zero.

HLA-C and HLA-DQ(B1) values of the patient record should be used for secondary sorting of the identified donors/CBUs.

The alternative phenotype does not go into the repeat search process. The patient must be known at the remote system (i.e. at least one PAT_UPD must precede the first ALM_REQ message).

It’s a common practice to look in WMDA XML whether mismatched donors are available for a certain patient. If the search was successful those donors can be requested from the hub found. With the ALM_REQ these donors are automatically added to EMDIS.

Multiple ALM_REQ should all provide a different phenotype from that provided by the last ALM_REQ message. Otherwise they can be rejected.

An ALM_REQ message with all P_MAX_DON_* fields set to zero (i.e.the default) makes no sense and can be rejected.

The patient’s matching preferences must not be respected for the donors returned i.e. ALM_REQ yields the default search results.