Pathology Informatics: Interfaces, Terminology, Autoverification, and Security
The informatics section tests how results travel from instrument to chart: interfaces, terminology standards, autoverification, security, and digital pathology.
Interfaces and standards
HL7 v2 messages carry orders (ORM) and results (ORU). Within ORU, OBX segments hold each observation: OBX-3 is the test identifier, OBX-5 the value, OBX-6 the units, and OBX-8 the abnormal flag. LOINC names tests and observations, SNOMED CT codes clinical findings, and DICOM handles images; FHIR is the modern RESTful standard for API access. Middleware sits between analyzers and the LIS, applying dilution, reflex, and delta-check rules.
Autoverification and governance
Autoverification releases results without human review only when every rule passes: reference range, delta check, critical value, instrument flags, and QC status. Audit trails, unique user IDs, and version control are required, and downtime procedures must allow results to be captured and reconciled afterward.
Security and analytics
Network segmentation, multi-factor authentication, patching, and vendor oversight defend against ransomware, which has halted laboratory operations in health systems. Dashboards monitor turnaround time, critical value notification, and QC trends.
Worked example
A creatinine of 0.2 mg/dL arrives for a patient whose prior value was 1.9 mg/dL. The delta-check rule blocks autoverification and routes the result to a technologist, who finds the specimen was drawn above an infusion line. The rule prevented a wrong result from reaching the chart.
Traps that cost marks
Overriding a critical value flag because the result resembles the previous one. Assuming an analyzer remains validated after a middleware rule change. Confusing LOINC (test identity) with SNOMED CT (result meaning) when mapping interface fields.