Recasts paragraph 1, adds analyst comments in paragraphs 6

April 16 (Reuters) - Abbott ABT.N cut its annual profit forecast on Thursday due to an impact from its $23 billion acquisition of cancer test maker Exact Sciences, sending its shares down 4% even as the medical device maker marginally beat quarterly results estimates.

Despite the 20 cent-per-share hit from the deal, CEO Robert Ford touted the addition of the high-growth business to the company's portfolio.

The deal, one of Abbott's largest acquisitions, is a major push into the fast‑growing cancer diagnostics market. It gives the company access to Exact's flagship colorectal cancer test Cologuard and early-stage breast cancer test Oncotype DX, helping offset revenue declines from its COVID-19 testing kits.

Exact's contribution was evident in first-quarter results, where growth in cancer diagnostics and continued strength in medical device demand helped Abbott post a modest beat on both earnings and revenue.

Analysts, however, flagged weakness in its nutrition business, where sales declined 6% year-over-year, as well as lighter-than-anticipated growth from diabetes and structural heart devices within its largest medical devices segment.

"Given a noisy quarter, with continued Nutrition weakness...we expect shares to be pressured," Citi analysts said in a note.

The medical device maker now expects adjusted profit per share between $5.38 and $5.58 for 2026, compared with its previous forecast of $5.55 to $5.80 per share.

On an adjusted basis, the company reported profit per share of $1.15, compared with analysts' estimate of $1.14, according to data compiled by LSEG. Total revenue was $11.16 billion, compared with expectations of $11 billion.

Quarterly sales in Abbott's medical devices segment grew 13.2% to $5.54 billion, beating estimates of $5.29 billion, driven by demand for certain heart devices. Sales of its continuous glucose monitors grew 14.2%.

Sales in its diagnostics segment grew 6.1% to $2.18 billion, slightly beating the estimate of $2.1 billion.

Abbott expects second-quarter adjusted earnings per share of $1.25 to $1.31, compared with estimates of $1.37 per share.