A roaming wireless user device on a Visited Public Land Mobile Network (VPLMN) may initiate a Long-Term Evolution (LTE) emergency call to a Public Safety Answering Point (PSAP). Accordingly, a Proxy Call Session Control Function (P-CSCF) of the VPLMN may receive an anonymous Session Initiation Protocol (SIP) invite message for the LTE emergency call. The anonymous SIP invite message lacks a Mobile Station International Subscriber Directory Number (MSISDN) of the wireless user device but has an International Mobile Equipment Identity (IMEI) of the wireless user device. The anonymous SIP invite message is forwarded to a Location Retrieval Function (LRF) in a Gateway Mobile Location Center (GMLC) of the VPLMN. The LRF obtains a MSISDN of the wireless user device that matches the IMEI in the anonymous SIP invite message from a database of the GMLC, such that the MSISDN is routed with the LTE emergency call to the PSAP.