For a brief period after hours on Tuesday, shares of Apple (NASDAQ: AAPL) rose above Friday's closing price for the first time since chief executive Steve Jobs announced he was taking another medical leave. But it took a 71 percent increase in first-quarter revenue to push Apple shares as high 357 in Tuesday's post-session trading before they fell back to 345.18, just 4.53, or 1.3 percent above Tuesday's close of 340.65. (Also see: Apple reported first-quarter profit of $6 billion) Apple's stock struggled throughout Tuesday, finishing 7.83, or 2.25 percent below Friday's close of 348.48. It had started the day with a plunge to 326, as investors sold off in reaction to Monday's news about the 55-year-old Jobs, who took a six-month medical leave in 2009, during which he received a liver transplant. In 2004, Jobs was diagnosed with pancreatic cancer, eventually having a tumor removed. Investors now must try to reconcile Apple's powerful new revenue stream -- it sold 7.33 million iPads in Q1 -- and bullish forecast with growing concerns about when (and whether) Jobs will return full-time to his post as chief executive. Unlike two years ago, Jobs didn't put a time limit on this medical leave. There's no doubt that Apple currently is hitting on all cylinders. In addition to the success of the iPad, the iPhone continues to do well -- sales reached 16.24 units in Q1, up 86 percent over the previous year -- and is expected to do even better once Verizon begins carrying the smartphone next month. The company's Q1 net income of $6 billion, or $6.43 a share, was 78 percent above last year's $3.38 billion, or $3.67 a share, while revenue was $26.74 billion, up 71 percent from $15.68 billion a year ago. Consensus estimates had called for earnings of $5.42 a share on sales of $24.4 billion. Apple forecast second-quarter revenue of $22 billion and net income of $4.90 per share, above analyst estimates of $20.9 billion in revenue and per-share earnings of $4.48. Hanging over it all, however, is the future of Apple's co-founder, who, more than most CEOs, is seen as an undisputed product and market visionary. While chief operating officer Tim Cook -- who is stepping in for the third time since 2004 to run the company on a day-to-day basis -- is viewed with great regard in the industry, there's little doubt that many view Jobs as the indispensable architect of Apple's success. Lingering questions about his health could put downward pressure on a stock that has continued to ascend to record highs.
Chris Nerney writes about the business side of technology market strategies and trends, legal issues, leadership changes, mergers, venture capital, IPOs and technology stocks. Follow him on Twitter @ChrisNerney.