NEW YORK (AP) — Shares of NxStage Medical Inc. fell Wednesday to their lowest level in more than two years after the medical device maker offered a disappointing third-quarter forecast.

Its financial results for the second quarter were similar to Wall Street estimates, but NxStage forecast a larger loss and slightly less revenue than analysts were expecting for the third quarter.

The Lawrence, Mass., company said its lost $5.1 million, or 9 cents per share, in the three months ended June 30 versus a loss of $5.6 million, or 10 cents per share, a year earlier.

Its revenue grew 10 percent to $59 million from $53.8 million on higher sales of its NxStage System One home kidney dialysis system.

Analysts expected a loss of 9 cents per share on $58.2 million in revenue, according to FactSet.

In the third quarter NxStage expects to lose 6 to 8 cents per share while reporting $60 million to $61 million in revenue. On average, analysts expect a smaller loss of 5 cents per share and higher revenue of $61.9 million.

NxStage maintained full-year estimates, saying it should lose 25 to 32 cents per share in 2012 on $240 million and $245 million in revenue. Analysts are expecting a loss of 27 cents per share on $241.5 million in revenue.

NxStage Medical stock declined $2.79, or 17.6 percent, to $13.06 in afternoon trading, after trading as low as $13 earlier in the session, their lowest level since June 2010.