Dataset Information

Frequency of icteric interference in clinical chemistry laboratory tests and causes of severe icterus

ABSTRACT:

Objectives

The aims of this study were to identify the causes of severe icterus in an academic medical center patient population and to assess the impact of icterus on clinical chemistry testing using assay package insert thresholds.

Design

and Methods: In this retrospective study at an academic medical center core clinical laboratory, icteric, hemolysis, and lipemia indices were available for all serum and plasma chemistry specimens analyzed on Roche Diagnostics cobas 8000 analyzers over a 12-month period, encompassing 414,502 specimens from 94,081 unique patients (51,851 females; 42,230 males) including children, inpatient, outpatient, and emergency department patients. Extensive chart review was done for all 57 patients (4 pediatric, 53 adult; 534 total specimens) who had one or more samples with an icteric index of 40 or higher (defined as severe icterus).

Results

Specimen icteric index exceeded package insert icteric index thresholds in 0.14% of clinical chemistry assays, with the highest number of instances for creatinine (1358 samples, 0.6% of total tests), total protein (1194 samples, 2.2%), and ammonia (161 samples, 3.9%). The 57 patients with an icteric index of 40 or higher accounted for 49.7% of all instances where the icteric index exceeded the specific assay package insert limit. The most common etiologies of this group of 57 patients were alcohol-related liver disease (34 patients), biliary tract disease (7 patients), and neoplasms (6 patients).

Conclusions

Approximately half of all instances where specimen icteric index exceeded assay package insert thresholds occurred in a small cohort of patients with severe liver/biliary tract disease. Graphical abstract Image 1 Highlights • Specimen icteric indices exceeded package insert icteric index thresholds for 0.14% of clinical chemistry tests ordered at an academic medical center.• Icteric interference exceeding package insert thresholds had the most overall occurrences for enzymatic creatinine, total protein, and ammonia.• Only 57 of 94,081 unique patients (0.06%) with severe icterus accounted for nearly half of instances where the icteric index exceeded the package insert limit for a specific assay.• The small cohort of patients with severe icterus had high mortality generally associated with cirrhosis, biliary disease, or aggressive metastatic cancer.• Icteric indices exceeding 20 were mostly comprised of patients with predominantly conjugated hyperbilirubinemia.

SUBMITTER: Mainali S

PROVIDER: S-EPMC8567001 | biostudies-literature |

REPOSITORIES: biostudies-literature

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