Seems that official LOINC has only Florescent in-situ hybridization (FISH). However, we need to differentiate ISH, FISH, CISH and SISH because of different test sensitivity and operation need.
Currently, we have created local extension code to solve this problem. However, there is no reference on the syntax of the LOINC long common name for submission.
The Chromogenic terms are for mainly coagulation assays (in the analyte/component) with a few hematology and toxicology tests. The FISH methods are tied to molecular and chromosomal levels of testing. I do not think that’s a similar comparison.
I don’t believe the Regenstrief team has received requests for the different ISH methods. Anyone is welcome to introduce the topic with a submission and references.