Case report · The Pan African medical journal · 2018Conflicts declared

Sunflower seeds caused a rectal seed bezoar in one man

What it found

A 64-year-old man who ate large amounts of unshelled sunflower seeds over a week developed a hard mass of seeds stuck in his rectum, causing constipation and pain.

It had to be removed by hand under general anaesthesia.

What they found

Studies in people

The case

A 64-year-old man had a hard mass of sunflower seeds stuck in his lower rectum. He had eaten large amounts of unshelled sunflower seeds over the past week.

Symptoms and signs

He had faecal impaction, tenesmus and rectal pain for 24 hours. A rectal examination found a large mass with sharp edges stuck in the lower rectum, and rectoscopy showed small tears in the rectal lining from the sharp debris.

Treatment and outcome

Conservative measures did not work, so the mass was removed by hand under general anaesthesia. He was discharged on the 3rd day after surgery and at 30-day follow-up reported normal bowel movements and no more discomfort.

Who gets seed bezoars

The authors say rectal seed bezoars usually happen in people without risk factors. One study found risk factors in only 7.2% of patients with seed bezoars, compared to 80.9% of patients with seedless faecal impaction.

Other findings

How they form

Seeds pass through the stomach and small intestine because they are small, then build up in the colon. In the rectum the mass loses water and forms a hard bezoar that usually shows up as faecal impaction.

Diagnosis and treatment

The authors say a careful history and a rectal examination are the mainstays of diagnosis. Most rectal seed bezoars can be removed by hand under general anaesthesia, while seed bezoars in the small intestine usually need surgery.

What the authors conclude

“Seed bezoars are a subgroup of phytobezoars, usually found in the rectum of patients without predisposing factors, causing constipation and non-specific abdominal or anorectal pain.”
Manatakis D, Sioula M, Passas I, Zerbinis H, Dervenis C, 2018

Also in their conclusions

  • They say seed bezoars are usually found in the rectum of patients without predisposing factors, causing constipation and non-specific abdominal or anorectal pain.
  • They advise that careful history and digital rectal examination are essential for diagnosis, with rectoscopy and CT scans in selected cases.
  • They conclude that the majority of rectal seed bezoars can be manually disimpacted under general anaesthesia to minimise pain and discomfort.

How it was done

The authors wanted to share their experience with a rectal bezoar caused by sunflower seeds in an otherwise healthy adult, and to review the literature on seed bezoars in the gut.

They described one 64-year-old man who came to the emergency department with a 24-hour history of faecal impaction, tenesmus and rectal pain after eating large quantities of unshelled sunflower seeds over the past week. They also reviewed published cases of seed bezoars in the gastrointestinal tract.

What it can’t tell you

  • This is a single case report, so it cannot show how often sunflower seeds cause this problem or who might be at risk.
  • It cannot show whether eating sunflower seeds in smaller amounts or chewing them well would prevent a bezoar.

The paper

Title
Rectal seed bezoar due to sunflower seed: a case report and review of the literature
Type
Case report
Evidence
Studies in people
Summarised from
Full text
Cite
Manatakis D, Sioula M, Passas I, Zerbinis H, Dervenis C (2018). Rectal seed bezoar due to sunflower seed: a case report and review of the literature. The Pan African medical journal. doi:10.11604/pamj.2018.31.157.12539Free full textPubMed 31065317DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error