A 4-year-old girl was brought by her mother to the primary care clinic with concerns about rectal bleeding for 6 weeks.
The bleeding occurred daily only after a bowel movement and appeared to have a central dark streak of blood. The mother reported that the child had no signs of straining with bowel movements, no constipation, and no complaints of abdominal pain. The mother increased the child's dietary fiber after noticing the painless rectal bleeding but denied seeing hemorrhoids and reported that the child had no fever or chills. The child reported no associated nausea, vomiting, dysuria, or hematuria. The child had no recent travel or use of nonsteroidal anti-inflammatory drugs. The patient's parents were healthy and denied a family history of colon cancer, colon polyps, or inflammatory bowel disease (IBD).
The patient was alert, oriented, and not distressed. Her vital signs were within normal limits and included a BP of 116/82 mm Hg, heart rate of 105 beats/minute, respirations of 20, and temperature of 98.3 °F (36.8 °C). The child's height was at the 99th percentile for her age and she was at the 50th percentile for weight, measuring consistently on growth charts. A skin examination showed no telangiectasis or other rashes. Mouth examination showed no ulcerations. Abdominal examination showed normoactive bowel signs and her abdomen was nontender to palpation with no palpable mass. No masses, fissures, or bleeding were visualized on external rectal examination.
- IBD such as Crohn disease or ulcerative colitis
- polyposis syndrome
Initial laboratory assessment included a complete blood cell count, comprehensive metabolic panel, thyroid-stimulating hormone level, and tissue transglutaminase; all were within normal limits. The child was started on daily polyethylene glycol (PEG) and referred to a pediatric gastroenterologist. She continued to have bloody bowel movements for more than 3 months until the specialty consult, at which she was scheduled for a colonoscopy and flat abdominal radiograph. The radiograph showed mild stool impaction without intussusception. A week before the colonoscopy, the mother reported a friable erythematous mass protruding from the child's rectum only after a bowel movement. During a colonoscopy, the child was found to have six polyps ranging in size from 0.6 cm to 1 cm in the ascending, transverse, descending, and sigmoid colon and the cecum. Pathology results confirmed six juvenile polyps.
Diagnosis of juvenile polyposis syndrome was confirmed based on the pathology results and number of polyps. Because of the pathology results, IBD was ruled out. The patient was referred to a subspecialist on polyposis syndromes for further evaluation and surveillance. She subsequently underwent genetic testing for SMAD4 and BMPR1A genes, for which she was negative. The child underwent a repeat colonoscopy and endoscopy 12 months later. Four polyps were removed from the colon which were juvenile polyps based on pathology report. The patient will continue regular surveillance lifelong for malignancy due to juvenile polyposis syndrome.
Juvenile polyposis syndrome is a rare autosomal dominant condition that causes the formation of multiple polyps along the gastrointestinal tract.1 About half of the patients with this syndrome have a mutation of the SMAD4 and or BMPR1A gene that inhibits apoptosis pathways, leading to hamartomatous polyps.1 In the United States, the incidence of juvenile polyposis syndrome is 1 in 100,000 and the average age of diagnosis is 18.5 years.1 Patients with a family history of juvenile polyposis syndrome are at high risk of acquiring the disease at a young age and carry a 39% cumulative risk of developing colorectal cancer in their lifetime.1
Nearly 98% of the polyps associated with juvenile polyposis syndrome are in the colorectal region.1,2 The most common clinical manifestation is rectal bleeding caused by friable polyps.1 Patients with chronic rectal bleeding should be screened for iron-deficiency anemia. Other signs and symptoms include rectal prolapse, diarrhea, and abdominal pain due to obstruction. Patients with the SMAD4 mutation have extraintestinal manifestations combined with hereditary hemorrhagic telangiectasia (HHT).1 Patients with HHT will have frequent epistaxis, iron deficiency anemia, and telangiectasia of the buccal mucosa and skin.
Colonoscopy is used to diagnose juvenile polyposis syndrome. Clinically, the criteria for diagnosis are five or more juvenile polyps found in the colorectum, multiple polyps found in other parts of the GI tract, or any number of juvenile polyps found in a patient with a family history of juvenile polyposis syndrome.1 Patients meeting the criteria should undergo genetic testing to screen for SMAD4 and BMPR1A gene mutations. The case patient had a de novo pathologic variant causing juvenile polyposis syndrome. The child's presentation of juvenile polyposis syndrome was slightly unusual because of her young age.
Managing juvenile polyposis syndrome requires a routine screening for anemia due to rectal bleeding and associated extraintestinal manifestation. Because of the increased risk of developing colorectal cancer and other digestive cancers, patients should have long-term follow-up with a pediatric gastroenterologist. Routine colonoscopy is required to manage juvenile polyps. Preventive colon resection may be indicated to reduce the risk of colorectal cancer.
Although a rare disorder, polyposis syndromes should be a consideration for all patients complaining of rectal bleeding. Consider genetic testing in all patients with juvenile polyposis syndrome. Patients with this syndrome can lead normal lives but should be followed by a gastroenterologist because of the high risk of developing malignancy.
1. Dal Buono A, Gaiani F, Poliani L, Laghi L. Juvenile polyposis syndrome: an overview. Best Pract Res Clin Gastroenterol
2. Katabathina VS, Menias CO, Khanna L, et al. Hereditary gastrointestinal cancer syndromes: role of imaging in screening, diagnosis, and management. Radiographics