By Steve Gelsi

Shares of Tenet Healthcare Corp. (THC) rallied as much as 20% on Tuesday after Goldman Sachs upgraded the company to buy from neutral and said the share value of the hospital operator could double.

Tenet Healthcare jumped 42 cents, or 19%, to $2.67 on Tuesday morning. Shares traded as high as $2.72 earlier in the session.

Goldman Sachs analyst Shelly Gnall cited a favorable view of urban markets, continued margin improvement and removal of a leverage overhang as credit markets normalize.

Goldman lifted its price target for Tenet to $5 a share from $1 a share, and said the stock still has room to move up.

Since early March, hospital stocks and bonds have rallied about 120%, driven by strong first-quarter results and a positive long-term view on health reform, Gnall said in a note to clients.

Urban hospital operators such as Tenet, "outperformed and we look for this divergence to continue, reflecting an opportunity to take (market) share," Gnall said.

"The urban operators also have more flexibility to divert non-emergent cases which will become increasingly important if the number of uninsured patients rises and self-pay collection rates decline as unemployment rates drag in the second half of the year."

Still, Goldman cited some risks that remain, including an earnings impact from the slower economy and the lower hospital reimbursements.

Separately, Goldman downgraded shares of LifePoint Hospitals (LPNT) to neutral from buy. Shares rose 60 cents to $26.34.

- Steve Gelsi; 415-439-6400; AskNewswires@dowjones.com