A Shared Diagnostic Stewardship Approach toward Improving Autoimmune Encephalopathy Send-out Testing Utilization.

Area of Science:

• Neurology
• Clinical Diagnostics
• Laboratory Medicine

Background:

• Autoimmune encephalopathy (AE) panels are often costly send-out tests with variable ordering patterns and unclear clinical utility.
• Lack of consensus on AE panel selection and interpretation poses challenges for laboratories and clinicians.
• A multidisciplinary diagnostic stewardship committee (DSC) was formed to address these issues.

Purpose of the Study:

• To develop and implement a novel algorithm for ordering AE panels.
• To improve the diagnostic yield and cost-effectiveness of AE testing.
• To standardize AE panel selection based on diagnostic criteria and practice guidelines.

Main Methods:

• Analysis of AE panel ordering patterns and true-positive rates in 2018.
• Development of a diagnostic algorithm integrating clinical criteria and expert input.
• Assessment of the algorithm's efficacy by comparing pre- and post-implementation ordering data, costs, and true-positive rates.

Main Results:

• In 2018, 77 AE panels cost $137,510 with a 10% true-positive rate.
• Pre-algorithm implementation (5 months): 55 panels cost $105,120 with a 3.6% true-positive rate.
• Post-algorithm implementation (5 months): 23 panels cost $50,220 with a 13% true-positive rate, a 43% reduction in orders.

Conclusions:

• The developed algorithm successfully identified at-risk populations for autoimmune encephalopathy disorders.
• Implementation of the AE panel ordering algorithm led to a significant increase in the true-positive rate.
• The algorithm resulted in substantial cost savings and a marked decrease in unnecessary testing.