Aß42-Aß40-Ratio (csf) (Cerebrospinal fluid (csf), frozen)
| Testcode: | E_ABETAQ |
| Specimens: | Cerebrospinal fluid (csf), frozen |
| Info: | General guidelines for collection and shipment of csf samples •Use polypropylene (PP) tubes. No glass and no polystyrene (PS) tubes. Close the container lid securely to prevent leakage. Label each CSF sample with patient´s data (name, DOB) and as "CSF". •Calculate sufficient volume of CSF for all requested tests and submit it in 3-4 aliquots (e.g. 3 x 3 ml), as some measurements are performed at external laboratories. •For analysis strictly requiring frozen samples, a separate sample is needed to avoid repeated freeze-thaw cycles. •For Oligoclonal bands (OCBs) and antibody index (ASI), collect serum and CSF simultaneously (within <1 hour of each other) and always submit them together. •For PCR testing separate sterile sample is required.
The "Alzheimer's disease" panel includes testing for Tau protein, phospho-Tau, and the Aβ42/A& |
| includes following tests: | Beta Amyloid 1-40 (ELISA) (csf) (Cerebrospinal fluid (csf)) Beta-Amyloid 1-42 (ELISA) (csf) (Cerebrospinal fluid (csf), frozen) |
| Preanalytics/Notes: | General guidelines for collection and shipment of csf samples •Use polypropylene (PP) tubes. No glass and no polystyrene (PS) tubes. Close the container lid securely to prevent leakage. Label each CSF sample with patient´s data (name, DOB) and as "CSF". •Calculate sufficient volume of CSF for all requested tests and submit it in 3-4 aliquots (e.g. 3 x 3 ml), as some measurements are performed at external laboratories. •For analysis strictly requiring frozen samples, a separate sample is needed to avoid repeated freeze-thaw cycles. •For Oligoclonal bands (OCBs) and antibody index (ASI), collect serum and CSF simultaneously (within <1 hour of each other) and always submit them together. •For PCR testing separate sterile sample is required.
The "Alzheimer's disease" panel includes testing for Tau protein, phospho-Tau, and the Aβ42/Aβ40 ratio. Tau protein and phospho-Tau can be requested individually (500 µl CSF per analyte). Testing them as a combined panel is recommended for greater clinical diagnostic value (1.5 ml CSF total). β-Amyloid 1-40 can only be requested in combination with β-Amyloid 1-42 for the calculation of the ratio. Freeze CSF as multiple aliquots (approx. 2–3 aliquots) immediately after collection and ship them to the laboratory in a frozen state, as Alzheimer's-related proteins are highly unstable. For further analyses using CSF, please refer to the "General guidelines for collection and shipment of CSF samples." |
| Method: | ELISA |
| Set-up: | Mon Tue Wed Thu Fri Sat Sun |
| Duration: | 7 days |
| Indication/Significance: | Suspected dementia |
| Interpretation: |
β-amyloid peptides more… β-amyloid peptides are characteristic in Alzheimer's disease and other forms of dementia with progressive loss of memory. β-amyloid peptides with amyloidogenic and neurotoxic properties are cleaved of amyloid precursor protein (APP) by proteinases. The cleavage products are deposited in extracellular spaces in the central nervous system and are detectable in csf. Beta-amyloid peptide (1-42) is considered a marker of senile plaques and is involved in the neuronal damage in dementia syndroms. In the case of Alzheimer's dementia, cerebral amyloid angiopathy, Lewy body dementia and other neurodegenerative syndroms, decreased results for ß-amyoloids are detectable. Parallel investigation of tau and phospho-Tau as well as determining the amyloid ratio (Aβ1-42 × 10/Aβ1-40) improves the sensitivity and specificity of the test. In people with Trisomy 21 the genetic defect increases the beta-amyloid values 40 and 42, so that the amyloids which are typically lower in Alzheimer's disease are incorrectly high. |
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Abrechnung GOÄ
Die Kosten werden für den i. d. R. genutzten 1,15-fachen GOÄ-Satz dargestellt. Wird die Untersuchung nicht in Ihrem regionalen Labor durchgeführt, erfolgt die Analyse in dem Labor, das im Leistungsverzeichnis genannt ist. In diesem Fall gilt der dort für die Untersuchung angegebene Preis.