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Connecting a Sysmex KX-21N to your LIS or EHR
Quick answer
Yes. The KX-21N has a host computer output on an RS-232 port. Catenix reaches that port through a serial device server, receives each count with its sample number and sends it on to your EHR or LIS. The output format and serial settings are confirmed on your unit during setup.
The KX-21N is a compact Sysmex 3-part differential system with 17 reportable parameters and WBC, RBC and platelet histograms, running up to 60 samples an hour from 50 microlitres of whole blood, or 20 microlitres in pre-dilute mode. Sysmex pitched it at clinic satellite labs and as a back-up to its 5-part analysers.
Its connectivity is from an earlier era: a built-in thermal printer, an optional handheld barcode reader and one RS-232 line to a host computer. That serial line is all Catenix needs.
| What | How Catenix handles it |
|---|---|
| Parameters | 17, with a 3-part WBC differential |
| Histograms | WBC, RBC, PLT |
| Speed | Up to 60 samples per hour |
| Host output | RS-232, bridged with a serial device server |
| Sample number | Up to 15 digits, optional handheld barcode reader |
| On-board memory | 300 results with histograms |
From printer era to EHR
In many labs the KX-21N's results are still read off its thermal printout and keyed in. Connecting the host port ends that. A serial device server next to the analyser puts the RS-232 line on the network, and the Catenix gateway listens on it, reconnecting by itself if the network blips.
Sample numbers do the matching
The analyser holds a sample number of up to 15 digits, read with the optional barcode reader or typed in. Catenix uses that number to find the EHR order and attach the result. Because there is no public description of orders going back to the KX-21N, we treat it as results-only: tests are run on the analyser and the sample number links them. Unmatched counts wait for review.
Controls from the six QC files
The KX-21N has two QC programs, Levey-Jennings and X-bar, with six QC files. Where control results come out of the host port, Catenix files them as QC, applies Westgard rules against your targets and keeps its own Levey-Jennings history. A failed control holds that test's patient results. Every message is stored with its result, and results wait on site through any internet outage.
Sysmex and KX-21N are trademarks of their owners. Catenix is an independent connectivity provider, not affiliated with or endorsed by Sysmex.
Questions people ask
How does the Sysmex KX-21N connect to a computer?
Through its RS-232 host output. A serial device server puts that port on the network for the Catenix gateway.
Can the KX-21N read barcodes?
Yes, with the optional handheld barcode reader. Sample numbers can be up to 15 digits.
Does connecting the KX-21N need a new analyser?
No. The existing host port is used, and the format settings are confirmed on your unit at setup.
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Product and company names are trademarks of their owners and are used for identification only. Catenix moves, stores and displays results with traceability; it does not interpret results or give clinical advice. Reviewed November 2026.
Tell us your setup
Send us your analyser and the system you want results in, and we will confirm how it connects, usually within one working day. Ask about your setup.