Labcorp test details for Testosterone, Free, Equilibrium Ultrafiltration With Total Testosterone
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Testosterone, Free, Equilibrium Ultrafiltration With Total Testosterone
TEST: 081786
Methodology
Free: equilibrium ultrafiltration;
total: electrochemiluminescence immunoassay (ECLIA)
Elecsys Testosterone II cobas®
English
System information
For cobas e 411 analyzer: test number 111 For MODULAR ANALYTICS E170, cobas e 601 and cobas e 602 analyzers: Application Code Number 216
Intended use
Immunoassay for the in vitro quantitative determination of testosterone in human serum and plasma.
The electrochemiluminescence immunoassay “ECLIA” is intended for use on Elecsys and cobas e immunoassay analyzers.
Limitations - interference
The assay is unaffected by icterus (bilirubin < 513 µmol/L or < 30 mg/dL), hemolysis (Hb < 0.372 mmol/L or < 0.600 g/dL), lipemia (Intralipid < 1000 mg/dL) and biotin (< 123 nmol/L or < 30 ng/mL).
Criterion: Recovery within ± 10 % of initial value (concentration range > 1‑15 ng/mL), recovery within ± 15 % of initial value (concentration range > 0.5‑1 ng/mL) and recovery of ± 0.075 ng/mL (concentration range of 0.150‑0.500 ng/mL).
Samples should not be taken from patients receiving therapy with high biotin doses (i.e. > 5 mg/day) until at least 8 hours following the last biotin administration.
No interference was observed from rheumatoid factors up to a concentration of 1000 IU/mL.
In vitro tests were performed on 18 commonly used pharmaceuticals. No interference with the assay was found.
Two special drugs were additionally tested.
Strong interaction with Nandrolone (INN international nonproprietary name, WHO) was found. Do not use samples from patients under Nandrolone treatment.
In isolated cases, elevated testosterone levels can be seen in samples from female patients with end-stage renal disease (ESRD).
Implausible elevated testosterone values in women should be verified by an extraction method or a validated LC‑MS/MS tandem method.5
In rare cases, interference due to extremely high titers of antibodies to analyte‑specific antibodies, streptavidin, or ruthenium can occur. These effects are minimized by a suitable test design.
For diagnostic purposes, the results should always be assessed in conjunction with the patient’s medical history, clinical examination, and other findings.