# GKZ: Counter, Differential Cell

- Device class: 2; regulation: 21 CFR 864.5220; FDA's rule: 510(k) required
- FDA decisions: 381
- 510(k) review time 2021–2025: median 255 days (middle half 134–384)
- Recalls: 181 (2 Class I)
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026; MAUDE to Sep 30, 2026

## Decisions per year (last 10)
- 2016: 3
- 2017: 4
- 2018: 3
- 2019: 5
- 2020: 1
- 2022: 3
- 2023: 4
- 2024: 3
- 2025: 4
- 2026: 4

## Most-cited predicates
- K112605: Sysmex XN-Series (2012), cited by 13
- K011342: Coulter LH 750 Hematology Analyzer, Model 6605632 (2001), cited by 8
- K974360: Multitest CD3/CD8/CD45/CD4 (1998), cited by 7
- K992875: Sysmex XE-2100, Automatated Hematology Analyzer (1999), cited by 5
- K990172: Tetraone System for Epics XL Flow Cytometry Systems with Cyto-Stat Tetrachrome CD45-Fitc/CD4-RD1/CD8-Ecd/CD3-PC5 Monocla (1999), cited by 5
- K973483: Facscomp Software and Calibrite Beads for Use in Flow Cytometer Instrument Set (1998), cited by 5
- K913192: Simultest (TM) Imk-Lymphocyte (1992), cited by 5
- K961439: Abbott Cell-Dyn 4000 System (1996), cited by 5
- K140911: Unicel DXH 800 Coulter Cellular Analysis System/ Unicel DXH Slidemaker Stainer Coulter Cellular Analysis System (2014), cited by 5
- K071967: Sysmex XE-5000 (2007), cited by 4

Source page: https://510kreport.com/product-code/GKZ
Data by year (CSV): https://510kreport.com/product-code/GKZ.csv