UPDATE 1-BTG Pactual fourth-quarter profit up 42% on higher revenue

(Updates with additional results, management comments)

SAO PAULO, Feb 16 (Reuters) - Brazilian lender Banco BTG Pactual SA on Wednesday posted a 41.7% jump in fourth-quarter profit to 1.782 billion reais ($345.42 million) on rising revenue in almost all its businesses.

Total revenue reached 3.489 billion reais in the quarter, up 23% from a year earlier, mainly boosted by sales and trading, wealth management and consumer banking.

The bank posted revenue of 917 million reais in its sales and trading unit, up 22% year-over-year, helped by a spike in Brazil's benchmark interest rate.

Amid Brazil's economic slowdown, BTG's net new money for its asset and wealth management units decelerated in the fourth quarter to 64 billion reais, versus 87.7 billion reais in the previous three months. Both units ended 2021 with 980.5 billion reais in assets.

The lender's loan book reached 106.6 billion reais in December, 9.2% up from September. BTG said it plans to continue to expand its loan book in 2022, as it expects to launch new credit lines backed by credit card receivables and boost offers to small companies.

Its operating expenses continued growing at a fast pace - up 30% from a year earlier - as BTG expands into retail banking and grew its headcount by almost 50% from a year earlier, to 5,211 employees.

BTG's return on equity, a gauge of profitability, was at 19.4%, 0.7 percentage points below the previous quarter.

($1 = 5.1590 reais) (Reporting by Carolina Mandl Editing by David Goodman and David Evans)