DaVita Inc. shares gained nearly 8 percent Friday after the company reported profit had doubled on stronger revenue.

DaVita reported second-quarter net income of $125 million ($1.17 per share), a 98 percent jump over $63 million (60 cents) from the same period a year earlier, thanks mainly to acquisitions and a larger number of patients. The results beat analysts’ expectations of 77 cents per share, according to Thomson Financial.

Sales for the El Segundo-based dialysis center operator rose 9 percent to $1.3 billion, which was in line with Wall Street’s expectations. During the quarter, total treatments rose to 3.8 million from 3.6 million.

The recent quarter included a valuation gain related to a product supply agreement, and gains on the sale of investment securities. Excluding those, income from continuing operations was $88.7 million, or 83 cents per share.

Shares in DaVita gained $4.03, or 7.6 percent, to $57.20 in afternoon trading Friday on the New York Stock Exchange.