Week 4 - Case File -Internal Medicine, Section - Gastrointestinal System, Case Study - Chronic Constipation Online Only

Discipline: Nursing

Type of Paper: Question-Answer

Academic Level: Undergrad. (yrs 3-4)

Paper Format: APA

Pages: 4 Words: 1000


A 54-year-old woman presents to the clinic with mild intermittent and diffuse abdominal pain that she has had for many years. In the past, she states the pain has been worse when she has been constipated. The pain improved with a bowel movement or passing gas. Her current pain lasts a few seconds and then resolves on its own multiple times a day. She reports that her symptoms have worsened since her hip replacement two weeks ago. She typically has to squeeze very hard to have a bowel movement. Her last bowel movement was 4 days prior to presentation. She says that she is passing gas and denies any nausea, vomiting, or fevers at home. Her diet is variable, but she dislikes vegetables and admits that she frequents a local fast-food restaurant 2-3 times per week. Her medical history is significant for arthritis, hypertension, and type 2 diabetes. She takes metformin, lisinopril, and amlodipine, and she has started to take oxycodone daily since her surgery. There is no family history of inflammatory bowel disease, but her father was diagnosed with colon cancer at the age of 75. She has never had a colonoscopy before. On physical exam, the patient is in no acute distress and has a soft, distended abdomen that is tender to deep palpation throughout all 4 quadrants. Bowel sounds are hypoactive. A rectal exam demonstrates an external hemorrhoid, hard stools in the rectal vault, and no gross mass or bleeding. Fecal occult blood testing is negative.


What is the most likely diagnosis?

What would be alarm signs and symptoms?

What is your next step in management?

Answers to Int Med Case 67: Chronic constipation

Summary: A 54-year-old woman presents with

  • Intermittent, colicky, mild diffuse abdominal pain that improves with bowel movements

  • No evidence of obstipation (inability to pass gas)

  • No peritoneal signs on abdominal exam

  • A negative fecal occult blood test

  • Never having a colonoscopy in the past

Most likely diagnosis: Chronic constipation exacerbated by narcotic use.

Alarm signs and symptoms: Failure to have a bowel movement, failure to pass gas, or the presence of peritoneal signs, bleeding, or microcytic anemia.

Next management step: Suggest tapering off her narcotics, start daily laxatives, and recommend fiber supplementation and more exercise. Assess for hypothyroidism. If symptoms persist, evaluate for inflammatory bowel syndrome-constipation (IBS-C). Additionally, given the patient’s age, a routine screening colonoscopy should be performed to rule out colon cancer.



This 54-year-old woman has a long history of constipation symptoms that have worsened over the past 2 weeks since her hip replacement. Notably, the patient does not have any symptoms of bowel obstruction or alarm symptoms that may indicate a more serious problem. For example, the failure to have a bowel movement or pass gas would suggest a mechanical bowel obstruction and could be a surgical emergency. Peritoneal signs may be caused by diverticulitis, appendicitis, or inflammatory bowel disease. Colonic bleeding may indicate diverticulosis or colon cancer. Notably, microcytic anemia is one the most common presentations of colorectal cancer. This patient’s diet appears poor in fiber and may be a contributor of the constipation. The first steps in the management of this patient would include:

  • Reassurance that this is likely not a serious issue

  • Counseling toward decreasing opioids

  • Increasing fiber, water intake, and exercise

  • Checking the thyroid stimulating hormone (TSH) level

  • Recommending a screening colonoscopy



  1. Describe the clinical presentation of chronic constipation. (EPA 1)

  2. Describe the differential diagnosis, including alarm symptoms of chronic constipation. (EPA 2)

  3. Describe the evaluation of a patient with chronic constipation. (EPA 1, 3)


CONSTIPATION: Having fewer than 3 bowel movements per week in the setting of the following symptoms: straining to stool, manual disimpaction, sensation of incomplete evacuation, abdominal bloating, or hard/lumpy stools.

CHRONIC CONSTIPATION: Constipation lasting for at least 3 months.

PRIMARY CONSTIPATION: Constipation caused by dysregulation of colonic motility.

SECONDARY CONSTIPATION: Constipation caused by another disease or illness.

IRRITABLE BOWEL SYNDROME-CONSTIPATION (IBS-C): Recurrent abdominal pain at least 1 day per week and 2 of the 3 following symptoms: (1) change in stool form; (2) change in stool frequency; and (3) relief of abdominal pain with defecation.

Clinical Approach


Constipation is a common complaint, estimated to be present in 15% of adults. It is more common in women, with a ratio of female:male patients of 3:1. Chronic constipation, defined as lasting for more than 3 months, is more common in older patients, particularly those older than 65 years of age. Race has a variable relationship to constipation, with dramatic differences reported in the literature. Constipation is an expensive disorder, with some estimates that over $821 million US dollars are spent on laxatives annually.


Chronic constipation can be divided into two categories: primary, where there are anal, rectal or colonic primary disorders, and secondary, where constipation is a consequence of another disease. Some of the more common causes of secondary constipation are listed in Table 67-1. Primary constipation occurs due to direct impairment of colonic regulation of stool movement and can be divided into 3 categories based on the Rome IV criteria:

  • 1) Functional Constipation: Requires that more than two symptoms of constipation (straining to stool, manual disimpaction, sensation of incomplete evacuation, abdominal bloating, or hard/lumpy stools) are present for more than 6 months and have occurred for at least 25% of all bowel movements in the past 3 months. Patients with functional constipation often have no or mild abdominal pain.

  • 2) Irritable Bowel Syndrome-Constipation Subtype (IBS-C): Recurrent abdominal pain at least 1 day per week and 2 of the 3 following symptoms: (1) change in stool form; (2) change in stool frequency; and (3) relief of abdominal pain with defecation.

  • 3) Defecatory Disorders: Caused by reduced forward movement or increased resistance to defecation. Abnormally elevated rectal tone or disorganized rectal muscle function (dyssynergia) are responsible for this subtype.

Causes of secondary constipation

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Table 67-1 Causes of secondary constipation
Structural abnormalities Metabolic disorders Neurological disorders Medication-induced disorders

Colon cancer

Anal fissure





Diabetes mellitus

Spinal cord injury

Parkinson disease



Anticholinergic agents

Calcium channel blockers

Clinical Presentation

History. Identifying what symptoms are most stressful to the patient determines the treatment. Defecation frequency, amount evacuated, and the consistency of stool (assessed with Bristol stool chart) are useful to determine the degree of constipation. Common symptoms include a sense of incomplete evacuation, abdominal bloating, and abdominal pain. Patients with defecation disorders will characteristically have a history of prolonged straining before successfully passing stools and respond poorly to laxative treatment.

Patients with IBS-C usually have a history of abdominal pain that improves with defecation; this pain is in direct relation to bowel movements, which is important because abdominal pain is a frequent symptom of all types of constipation. These patients usually commonly have concomitant anxiety disorders and may have upper gastrointestinal symptoms like dyspepsia.

Worsening pain with defecation is suggestive of an anal fissure. Additionally, paradoxical diarrhea and rectal incontinence can even occur, such as in cases of overflow constipation. In severe cases, chronic constipation can lead to fecal obstruction, producing pain that can cause altered mental status and even bowel rupture, although these events are rare.

Sexual and vaccination history should be obtained. Human papillomavirus (HPV) infection and anal cancer are more frequently seen in patients engaged in anal-receptive sex. Family history should be focused on the presence of colon cancer or inflammatory bowel diseases. A detailed medication list should be obtained since constipation is a side effect of many medications, particularly opioid narcotics. A history of weight loss or change in the color or appearance of stool may indicate cancer. Finally, diet and physical activity level should be assessed.

Physical Examination. The patient should be kept comfortable during this process and counseled about each maneuver. They may be placed in the left lateral decubital position with hips at 90 degrees. Importantly, the patient should be covered as much as possible, and a chaperone should be present for assistance. The anus should be inspected, with attention paid to the presence of an obstructing mass, anal fissure, rash, or external hemorrhoid. An incompletely closed anal canal with active stool seepage suggests muscle atrophy or neuronal injury. The patient should be asked to “push” and the descent of the pelvic muscles observed for any discoordination. The anal reflex can easily be tested by using a cotton tip and stroking centripetally in all four quadrants of the anus; abnormalities suggest neuronal dysfunction. Next, a gloved, lubricated finger should be inserted into the anal canal, feeling for any gross mass. The patient should be asked to squeeze the anal canal; they should be able to hold this for longer than 30 seconds. Failure to do so suggests pelvic muscle weakness; excessive contraction can suggest a defecatory disorder. The patient should also be asked to squeeze as if they were going to the bathroom; the pelvic muscles (puborectalis) should contract, and the external anal sphincter should relax. Abnormalities suggest dyssynergia. Where appropriate, particularly in post-menopausal women, a vaginal exam may be necessary to rule out pelvic organ prolapse.

Laboratory Values. Diagnostic testing revolves around ruling out secondary causes of constipation. The only screening test for which there is strong evidence is a complete blood count (CBC) to evaluate for anemia. Otherwise, clinical symptoms should guide laboratory evaluation. These include an evaluation for iron deficiency anemia, thyroid stimulating hormone (TSH) and free T4 levels to rule out hypothyroidism, a basic metabolic panel (BMP) to exclude hypokalemia or hypercalcemia, and a hemoglobin A1c to evaluate for the presence of diabetes. Fecal occult blood testing can be used to look for microscopic blood in the stool.

Other Diagnostic Tests. Colonoscopy is important if a patient meets age-appropriate guidelines for screening colonoscopy or has any alarm symptoms that may suggest colon cancer. Anorectal manometry, balloon expulsion test, and magnetic resonance imaging (MRI) defecography are advanced techniques with specific indications and should only be employed by specialists.


In the absence of organic complications (eg, colon cancer), management of constipation revolves around improving the patients’ quality of life. Medications that can cause constipation, narcotics among them, should be discontinued if possible. Comorbid conditions (eg, hypothyroidism, hypokalemia) should be treated.

Fiber. After secondary causes have been ruled out, fiber supplementation, followed by laxatives, can be employed. Recommended fiber intake is 25-30 g/day and can be accomplished with consumption of more fruits and vegetables or dietary supplements. Importantly, fiber supplementation may take up to one month to improve symptoms.

Laxatives. Laxatives can be divided into osmotic (eg, polyethylene glycol), stimulant (eg, senna), and secretagogues (eg, linaclotide) subtypes. Polyethylene glycol has the more supportive evidence and thus is the recommended first choice. Stimulant laxatives are used on a rescue basis and have weaker evidence. Importantly, most laxatives should be administered 30 minutes after a meal to time best with colonic motility. Patients diagnosed with a defecatory disorder should undergo pelvic muscle retraining therapy, which includes biofeedback and pelvic floor muscle strengthening, rather than use laxatives, which are less helpful in this group.

Other Therapies. Scheduling bowel movements, particularly after meals, can be helpful. Dietary adjustment may be necessary. More exercise, particularly for IBS-C patients, can help alleviate symptoms. The involvement of a specialist is recommended with more advanced therapies such as linaclotide and lubipristone, which are only approved for use in IBS-C.

Referral. Patients with peritoneal signs (abdominal rigidity, rebound tenderness, involuntary guarding) or an inability to pass stool or gas need immediate evaluation and should be sent to the emergency department for further workup (Figure 67-1). Referral should be considered immediately in the presence of alarm symptoms (ie, those that indicate colon cancer may be present), which include:

  • Iron deficiency anemia

  • Blood in stool

  • Weight loss

  • Abrupt onset constipation

Figure 67-1.

Example Algorithm of Chronic Constipation Management IDA, iron deficiency anemia

Additionally, patients who meet age-appropriate guidelines should be referred for routine screening colonoscopy. Failure to respond to fiber and laxatives should prompt referral for further workup and/or reconsideration of the diagnosis.


Prognosis of constipation is generally good. It is estimated that almost 90% of cases have no etiology and will resolve with simple interventions, such as fiber, adequate hydration, and exercise.

Case Correlation

See also Case 21 (Colitis and Inflammatory Bowel Disease) and Case 22 (Acute Diverticulitis).

  • Clinical Pearls

  • Constipation is defined as less than 3 bowel movements per week. Chronic constipation lasts for more than 3 months.

  • Patients with constipation who have “red flag” symptoms (eg, weight loss, evidence of bleeding, or anemia, sudden onset constipation) or who meet age-appropriate screening criteria should be referred for endoscopic examination.

  • Medications are common causes of constipation; a thorough medication reconciliation should be performed for all patients with constipation.

  • Opioids are a common cause of constipation and should be avoided when possible in patients prone to developing constipation.

  • When using laxatives, polyethylene glycol has the most evidence and thus should be used as a first-line medication when fiber supplementation fails.

  • Multiple therapies are typically required to treat chronic constipation. If patients fail initial therapy, referral to a gastroenterologist is appropriate for further management.

Question 1 of 4

A 25-year-old woman presents to your office with a chief complaint of abdominal pain of one month’s duration. She reports significant abdominal pain when she does not have bowel movements and improvement in pain when she defecates. She has frequent urges to go but is not able to defecate; she reports going to the bathroom 5-6 times a day. She is anxious about being a bridesmaid in an upcoming wedding because she is uncertain if she will be able to participate without running to the bathroom. She describes her stool as “hard and lumpy.” She denies any bleeding per rectum. She reports that her father had colon cancer at age 75. She also complains of abdominal pressure, bloating, and frequent burping, but she denies weight loss. Her stool sample is fecal occult blood negative. Which of the following is the most likely diagnosis?


Gastric ulcer


Irritable bowel syndrome, constipation subtype (IBS-C)


Irritable bowel syndrome, diarrhea subtype (IBS-D)


Colon cancer

You will be able to view all answers at the end of your quiz.

The correct answer is B. You answered B.


B. IBS-C. This patient is a young lady who has abdominal pain that improves with defecation that has occurred for at least 1 year (more than 3 months) and has increased frequency of bowel movements, thus meeting criteria for IBS-C. A gastric ulcer (answer A) could certainly cause her dyspepsia symptoms, but this diagnosis would not explain the constipation and defecatory abdominal pain. Also, since the fetal occult stool is negative, peptic ulcer disease is less likely. IBS-D (answer C) is unlikely, given the absence of diarrhea. Colon cancer (answer D) should always be a consideration in anyone with chronic constipation; however, given her age, negative fecal occult blood test, and family history, colon cancer is less likely.


Question 2 of 4

A 26-year-old man comes into your office with complaints of constipation. He has had constipation for years, seen various physicians, and tried multiple medications and laxatives with no relief. He reports that he is having difficulty sleeping, has gained weight recently, and has worsening constipation. He also reports feeling depressed. His vital signs are notable for a heart rate of 55 beats per minute and blood pressure of 105/62 mm Hg. His neck shows no masses and no goiter. The abdomen is tender in the left upper quadrant, right lower quadrant, and epigastric region, although the tenderness is not reproducible. There is mild, non-pitting edema to the shins bilaterally. What is the best next step?


Order thyroid stimulating hormone (TSH) and free T4 levels.


Refer for further constipation evaluation.


Start treatment for IBS-C with linaclotide.


Start on sertraline and follow up in 6 weeks to evaluate treatment.

You will be able to view all answers at the end of your quiz.

The correct answer is A. You answered A.


A. Order TSH and free T4 levels. This patient demonstrates multiple signs of hypothyroidism, including weight gain, depression, worsening constipation, and non-pitting edema in the shins. A goiter does not need to be present in hypothyroidism. Depression may be related to this patient’s symptoms; however, evaluation for hypothyroidism should be performed first before treating depression (answer D). Further constipation workup (answer B) may be necessary; however, secondary causes of constipation should be excluded before these expensive tests are performed. IBS-C criteria (answer C) have not been met yet.


Question 3 of 4

A 59-year-old man arrives at the hospital for acute abdominal pain and altered mental status. A computed tomography (CT) scan performed in the emergency department demonstrates a large, 10-cm fecalith obstructing the recto-sigmoid junction. The patient has been taking oxycodone daily for over two years for lower back pain; this medication is believed to have caused his altered mental status and fecalith. He is taken to the operating room, where the fecalith is removed under general anesthesia. What therapy could have prevented this patient’s condition?


Methylnaltrexone use


Giving a bowel regimen


Avoiding narcotics


All the above

You will be able to view all answers at the end of your quiz.

The correct answer is D. You answered D.


D. All of the above. In general, all these interventions, most importantly avoiding narcotics (answer C), could have avoided this complication. Constipation can cause severe symptoms, including bowel obstruction and altered mental status. Patients who take narcotics should always have a bowel regimen added (answer B), particularly if they are starting to become constipated. This patient has back pain and likely has poor mobility at home that is contributing to his constipation. Methylnaltrexone (answer A) is an anti-opioid medication that prevents narcotics from slowing the bowel without preventing their systemic effects. It is approved to treat opioid-induced constipation and would have likely prevented this patient’s constipation.


Question 4 of 4

A 75-year-old man was diagnosed with functional constipation 4 weeks ago. He has recently tried to exercise more, has started eating more fiber, and is drinking more water. He comes back to the office and reports that his constipation is improving, but he is still having only two bowel movements per week and mild abdominal pain. He asks about a referral to a specialist. He had a colonoscopy 2 years ago that was normal. Which of the following is the best next step in management?


Refer to a gastroenterologist for further workup.


Start polyethylene glycol daily.


Start senna daily.


Start bisacodyl daily.

You will be able to view all answers at the end of your quiz.

The correct answer is B. You answered B.


B. Start polyethylene glycol daily. This patient has failed to respond to initial management for constipation; thus, his regimen should be broadened to include a laxative. Of the three laxatives listed, polyethylene glycol (PEG) has the best evidence basis and thus is likely to help. In the event that PEG does not help, senna (answer C) and bisacodyl (answer D) can be added. However, it may be necessary to perform more testing, assuming all secondary causes have been ruled out. This patient has not yet failed conservative management, and further referral (answer A) will be costly.


  • Reference

Bharucha,  A. E., Lacy,  B. E. (2020). Mechanisms, Evaluation, and Management of Chronic Constipation. Gastroenterology, 158(5), 1232–1249.e3. http://doi.org.su.idm.oclc.org/10.1053/j.gastro.2019.12.034

Bharucha,  A. E., Dorn,  S. D., Lembo,  A., Pressman,  A., Association,  A. G. (2013). American Gastroenterological Association Medical Position Statement on Constipation. Gastroenterology, 144(1), 211–217. http://doi.org.su.idm.oclc.org/10.1053/j.gastro.2012.10.029

Rao,  S. S. C. (2018). Rectal Exam: Yes, it can and should be done in a busy practice! American Journal of Gastroenterology, 113(5), 635–638. http://doi.org.su.idm.oclc.org/10.1038/s41395-018-0006-y

Calmilleri,  Michael, Murray,  Joseph A. Diarrhea and Constipation. In: Jameson  JL, Fauci  AS, Kasper  DL,  et al, eds. Harrison’s Principles of Internal Medicine. 20th ed. New York, NY: McGraw-Hill Education; 2018:259–269.