I’m working in a public hospital in Bahrain. The regulators have recently announced that we are to start reporting our Laboratory activity using the LOINC code set. Unfortunately we have no experience within the organization and I am seeking help in mapping the old internal descriptions/codes to the correct LOINC codes. Across the 8 specialist areas sections within the Lab, we currently offer around 2500 individual tests.
My assumption is that the description we have used to name our services are common typology and, as such, a good percentage of the mapping/re-coding could be performed as a desk exercise and the remaining requiring interaction with our people to get further clarifications.
Any recommendations on who may be able to assist us?
One thing you can implement easily is to ask to your lab systems & reagents suppliers for LOINC codes best describing their products. If not implemented by all manufacturers yet, a growing number of them is doing so.
The added value of using manufacturer established LOINC codes was recently documented . That study mentioned 3 such manufacturers : Abbott, bioMérieux, Roche. You can also watch Andrea Pitkus presentation at the last LOINC conference  presented that study.
More such manufactures may also be inquired to the LOINC team and the IICC 
hope this can help you,
1- Cholan RA, Pappas G, Rehwoldt G, Sills AK, Korte ED, Appleton IK, et al. Encoding laboratory testing data: case studies of the national implementation of HHS requirements and related standards in five laboratories. Journal of the American Medical Informatics Association. 2022.