* Q1 loss/shr $0.05 vs EPS $0.05 year earlier
* Q1 rev up 32 pct
* Q1 expenses up 43.5 pct
May 3 (Reuters) - Payment systems provider ACI Worldwide Inc posted a first-quarter loss hurt by higher expenses related to the acquisition of smaller rival S1 Corp last year.
ACI reported a net loss of $1.8 million, or 5 cents per share, compared with net income of $1.6 million, or 5 cents per share, a year earlier.
Revenue rose about 32 percent to $137.6 million.
Expenses rose 43.5 percent to $139.2 million.
Shares of the company closed at $40.05 on Wednesday on Nasdaq.