Alinity h-series System

The Alinity h-series System is an integrated hematology analyzer (Alinity hq) and optional slide maker stainer (Alinity hs) intended for screening patient populations in clinical laboratories. The Alinity hq performs complete blood counts and 6-part white blood cell differentials in whole blood samples, providing quantitative results for 33 measurands including cell counts, percentages, and indices. The Alinity hs automates blood film preparation and staining.

The subject device uses the same flow cytometry, hydrodynamic focusing, and absorption spectrophotometry methods as the predicate device (K220031). The hardware, reagents, calibrators, controls, specimen types, and system configurations remain identical. The only difference is the software: the subject device uses Alinity h-series Software Version 5.8, which includes a modified algorithm for basophil counting in samples where lymphocyte and basophil populations overlap, whereas the predicate used Version 5.0.

CLSI EP35 (anticoagulant comparability), CLSI EP28-A3 (reference range studies), and CLSI H26-A2 (carryover evaluation) are cited.

Substantial equivalence is established through analytical performance data replayed from the predicate device's 510(k) submission (K220031) using the modified algorithm. Precision, linearity, detection limits, and stability testing all met predefined acceptance criteria. Method comparison against the predicate and a reference analyzer (Sysmex XN-10) demonstrated acceptable regression analyses and bias at medical decision points. Critically, the algorithm modification reduces falsely elevated basophil counts in affected samples (67 specimens showed reduction from slopes of 2.22 to 1.17 for BASO) while maintaining equivalent performance for all other measurands including lymphocyte counts and WBC. The modification targets only the basophil counting logic without affecting hardware, intended use, or other analytical functions, making the device substantially equivalent with improved accuracy for a subset of samples.