Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of athenahealth (NASDAQ:ATHN), a cloud-based provider of practice management, electronic health records, and care coordination for medical practices around the country, skyrocketed as much as 26% after reporting better-than-expected fourth quarter earnings results.

So what: For the quarter, athenahealth delivered year-over-year revenue growth of a whopping 48% to $171.6 million as GAAP income more than doubled and adjusted EPS flew to $0.57. By comparison, Wall Street's consensus estimate had called for a profit of just $0.44 per share on $168.6 million in revenue. Excluding revenue generated from athenahealth's purchase of Epocrates, year-over-year organic growth totaled 28% to $149 million, and adjusted gross margin expanded 280 basis points to 66.2%.

Now what: While today's results were undoubtedly solid, I'm still not sold on athenahealth at these levels. On one hand, its growth rate is undeniably fast, and the push toward electronic and cloud-based practice management and care coordination is high among hospitals and medical clinics in an effort to streamline operations and save costs. The implementation of Obamacare should only further push clinics to seek out athenahealth's cloud-based management platforms.

On the other hand, this valuation is downright scary for anyone who has the slightest belief in value investing. At roughly 130 times forward estimates, a price-to-sales of nearly 12, and with costs soaring as the company spends heavily on R&D and marketing its product, it's difficult to see how investors are going to squeeze any more blood out of this turnip. That being said, I believe athenahealth is worth a watchlist add, but I personally fail to see how its share price can head any higher.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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