A 32-year-old primigravida woman at 24 weeks gestation comes to the office due to a change in bowel habits. For the past 4 weeks, the patient has had 3 or 4 loose, bloody stools per day and intermittent lower abdominal pain. On occasion, she experiences urgency to use the bathroom, but when she sits down on the toilet, she strains and produces very little stool. Two years ago, the patient had intermittent bloody stools that resolved without medication. Her pregnancy has been otherwise uncomplicated. Family history is noncontributory. She does not use tobacco, alcohol, or illicit drugs. At 20 weeks gestation, fetal ultrasound revealed a fetus at the 12th percentile for gestational age. Temperature is 37.5 C (99.5 F), blood pressure is 123/86 mm Hg, pulse is 98/min, and respirations are 16/min. The patient appears well and is in no apparent distress. There is no scleral icterus or conjunctival pallor. Cardiopulmonary examination is unremarkable. On abdominal examination, the uterus is at the umbilicus and fetal heart tones are 160/min; there is mild diffuse abdominal tenderness to palpation with no rebound or guarding. Which of the following is the most likely diagnosis for this patient?

Question

A 32-year-old primigravida woman at 24 weeks gestation comes to the office due to a change in bowel habits.  For the past 4 weeks, the patient has had 3 or 4 loose, bloody stools per day and intermittent lower abdominal pain.  On occasion, she experiences urgency to use the bathroom, but when she sits down on the toilet, she strains and produces very little stool.  Two years ago, the patient had intermittent bloody stools that resolved without medication.  Her pregnancy has been otherwise uncomplicated.  Family history is noncontributory.  She does not use tobacco, alcohol, or illicit drugs.  At 20 weeks gestation, fetal ultrasound revealed a fetus at the 12th percentile for gestational age.  Temperature is 37.5 C (99.5 F), blood pressure is 123/86 mm Hg, pulse is 98/min, and respirations are 16/min.  The patient appears well and is in no apparent distress.  There is no scleral icterus or conjunctival pallor.  Cardiopulmonary examination is unremarkable.  On abdominal examination, the uterus is at the umbilicus and fetal heart tones are 160/min; there is mild diffuse abdominal tenderness to palpation with no rebound or guarding.  Which of the following is the most likely diagnosis for this patient?

Quizplus · Accepted Answer

This primigravida patient with hematochezia, abdominal pain, and tenesmus (eg, fecal urgency followed by straining and inability to defecate) most likely has ulcerative colitis (UC). Pregnancy is a high-risk period for patients with UC due in part to placental cytokines that worsen colonic inflammation. Maternal complications include worsening UC disease activity, which can lead to severe hematochezia, anemia, and, in rare cases, toxic megacolon. Fetal risks include preterm delivery and small for gestational age. In addition, fertility rates are lower in those with active UC. Management of pregnancy in patients with UC ideally begins before conception because those with remission prior to pregnancy are more likely to have an uncomplicated course. Most medications used in the management of UC (eg, mesalamine, sulfasalazine, tumor necrosis factor-alpha inhibitors) are considered safe for continuation throughout pregnancy. These medications can also be continued during breastfeeding, with the exception of sulfasalazine, which is not recommended due to insufficient safety data. (Choice A) Gastrointestinal arteriovenous malformation (AVM) usually causes occult gastrointestinal bleeding and presents with iron deficiency anemia; hematochezia is less common. In addition, this patient lacks risk factors for AVM (eg, chronic kidney disease, aortic stenosis, and von Willebrand disease). (Choice B) Diverticular bleeding typically presents with hematochezia in the absence of abdominal pain. It is generally diagnosed in patients age >60; pregnancy is not considered a risk factor. (Choice C) Familial adenomatous polyposis (FAP) is an autosomal dominant condition characterized by hundreds of colonic adenomatous polyps. Affected patients universally develop colon cancer, often at a young age. This patient does not have any significant family history, making FAP unlikely. (Choice D) Internal hemorrhoids are very common in pregnancy and present with streaky, bloody stools in the setting of constipation and rectal itching. Internal hemorrhoids would not explain tenesmus and fetal growth restriction. (Choice E) Shigellosis presents acutely with fevers, abdominal pain, tenesmus, and bloody diarrhea for up to 7 days. It is unlikely in this patient, who has had symptoms for 4 weeks. Educational objective: Pregnancy is a high-risk period for patients with ulcerative colitis (UC) as there is often worsening disease activity that can lead to fetal complications, including preterm delivery and small for gestational age. Remission should ideally be achieved before conception. Most medications used to control UC are considered safe for continuation throughout pregnancy. References: Inflammatory bowel disease in pregnancy clinical care pathway: a report from the American Gastroenterological Association IBD Parenthood Project Working Group (http://www.ncbi.nlm.nih.gov/pubmed/30658060)

A 32-Year-Old Primigravida Woman at 24 Weeks Gestation Comes to the Office