Nadir (from the Arabic point of view) is generally understood to mean the lowest value of (measured) values in medicine, for example the viral load, blood pressure in mmHg or the PSA value in the screening of the prostate carcinoma. p>
Especially in the treatment of tumors (chemotherapy), Nadir refers to the maximum reduction in leukocytes (leucocyte-nadir) or neutrophil granulocytes (ANC-nadir). This reduction in the corresponding cell numbers is also referred to as leukopenia or neutropenia and is in most cases dose-limiting for the therapy or responsible for the resulting shortened therapy duration.
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