DaVita invests.

It may never become a major revenue source, but kidney dialysis center operator DaVita Inc.'s recent investment in a home dialysis company was seen on Wall Street as a wise way to cover another potential market for its services.

DaVita acquired a 7 percent stake Feb. 7 in Lawrence, Mass.-based NxStage Medical Inc., maker of a home hemodialysis system that the El Segundo company had been trying out. In addition to the $20 million investment, DaVita purchased the NxStage System One equipment it was using for $5 million and has agreed to future purchases.

The companies also will collaborate on research, public awareness and policy initiatives to promote wider use.

DaVita operates 1,300 outpatient facilities serving about 103,000 patients and analysts don't expect the company's home business to be any more than a fraction of that for now. But the bulky machine may be seen as a convenient option for younger patients.

"If you have 100,000 patients now, and maybe 5 percent of them might fit the profile and be trained to operate the equipment properly, then why wouldn't you want to tap into that market?" said Oppenheimer & Co. analyst Balaji Gandhi, whose own family had recently considered such a machine for an older family member.

Staff reporter Deborah Crowe can be reached at [phone], ext. 232, or at [e-mail].