Case 11: Dark stools

Last updated: November 3, 2021

Examinee instructionstoggle arrow icon

Opening scenario

William Johnson, a 65-year-old male; , comes to the doctor's office because of dark stools.

Vital signs

  • Temperature: 98.6°F (37.0°C)
  • Blood pressure: 125/80 mm Hg
  • Heart rate: 72/min
  • Respirations: 14/min

Examinee tasks

Patient encountertoggle arrow icon

Patient instructions

  • Point to the middle of your abdomen, just below the ribs, when the examinee asks you about the location of your pain. Tell the examinee that it hurts when he/she pushes on this area.
  • You are a patient in a hurry, with lots of work to do and not much time for this appointment.
  • You do not know the meanings of medical terms (e.g., endoscopy), and ask for clarification if the examinee uses them.
  • Use the checklists below for history, physical examination, and communication and interpersonal skills.

Challenge: When the examinee mentions which diagnostic tests are necessary, say: “I don't have time for all these tests! I have a lot of work to get done in the next few weeks!”

Focused historytoggle arrow icon

Hovering over or clicking on the speech bubbles in the lists below will reveal extra information about the adjacent term. However, clicking on links will cause you to navigate away from the current case, at which point your progress (i.e., your check marks) will be lost. If you do want more information on a subject, either open the link in a new tab or wait until you and your partner have finished the case and reviewed the check marks. Following the link to the patient note form or the abbreviation list will not interrupt your progress.

History of present illness

  • Chief complaint
  • Well, it is pretty gross, but when I go to the bathroom, I have noticed that what comes out is darker than usual.
    • Appearance
    • It is almost black; , and it is sticky.
    • Amount of black in stools (intermixed, on top)
    • The whole stool appears darker, and it is not only on top!
    • Presence of bright red blood
    • No.
    • Diarrhea/constipation
    • Diarrhea or constipation? No problem there.
  • Onset
  • 2 weeks ago.
  • Constant/intermittent
  • It has been the same color every time I have gone to the bathroom.
  • Precipitating events
  • None.
  • Progression
  • No.
  • Previous episodes
  • Never.
  • Frequency
  • I have about 2 bowel movements each day.
  • Alleviating factors
  • None.
  • Aggravating factors
  • None.
  • Associated symptoms
  • I have also had a stomach ache.
    • Location
    • Here .
    • Intensity (on a scale from 0–10)
    • 3–4.
    • Quality
    • It is a dull pain.
    • Onset
    • It also started 2 weeks ago.
    • Precipitating events
    • None.
    • Progression/constant/intermittent
    • The pain comes and goes; sometimes it is not there at all. But when it is there, it stays pretty steady at a 3–4.
    • Previous episodes
    • None.
    • Radiation
    • No.
    • Alleviating factors
    • None.
    • Aggravating factors
    • It gets worse when I eat something.

Review of systems specific to melena

  • Travel recently
  • No.
  • Nausea/vomiting
  • I felt a bit nauseous today. But I have not thrown up at all.
  • Fever/chills
  • No.
  • Night sweats
  • No.
  • Fatigue
  • No.
  • Rash/skin changes
  • No.
  • Chest pain/shortness of breath
  • No.
  • Urinary problems
  • No.
  • Appetite changes
  • Yes. I have had less of an appetite for 2 weeks; , because when I eat the pain gets worse.
  • Weight changes
  • Yes, I lost 1 kg (2.2 lb) in the past 2 weeks.
  • Dizziness
  • No.
  • New lumps
  • No.

Ask about dizziness, shortness of breath, and fatigue if you suspect significant blood loss.

Past medical history, family history, and social history

Communication and interpersonal skillstoggle arrow icon

Patient interaction

  • Examinee knocked on the door.
  • Examinee introduced him- or herself and identified his/her role.
  • Examinee correctly used the patient's name.
  • Examinee asked open-ended questions.
  • Examinee listened attentively (did not interrupt patient).
  • Examinee showed interest in the patient as a person (i.e., appeared caring and showed respect).
  • Examinee demonstrated ability to support patient's emotions (i.e., offered words of support, asked for clarification).
  • Examinee did not repeat painful maneuvers during physical examination.
  • Examinee discussed initial diagnostic impressions with the patient.
  • Examinee explained management plan.
  • Examinee used non-medical terms and provided reasons for planned steps in management.
  • Examinee evaluated patient's agreement with next diagnostic steps.
  • Examinee asked about concerns and/or questions.

Counseling and challenge

Suggested response to challenge: “Mr. Johnson, I can understand that it is difficult for you to find the time for diagnostic tests and that you have obligations at work. However, I think it is very important that we find out what is causing your dark stools and stomach pain. Dark stools can be a symptom of gastrointestinal bleeding, which can have dangerous consequences if not properly treated. With your permission, we will complete the necessary tests and do them as quickly as possible; we want to be thorough so we do not miss anything. Do you have any further questions?”

Patient notetoggle arrow icon

Further discussiontoggle arrow icon

Patient note

Differential diagnoses

  1. Gastric ulcer: This patient has multiple risk factors for gastric ulcer, including long-term NSAID use, smoking, and alcohol consumption. Epigastric pain that increases shortly after eating, epigastric tenderness, nausea, and melena are all common signs of a gastric ulcer that has begun to bleed, the most likely diagnosis in this case. Ibuprofen often masks the pain associated with the underlying gastritis. Once an ulcer develops and the pain and blood loss increase, there is then a sudden onset of symptoms.
  2. Chemical gastritis: This patient has multiple risk factors for chemical gastritis, including long-term NSAID use, smoking, and alcohol consumption. Gastritis can present with epigastric tenderness and nausea. However, blood loss is usually slow in gastritis, leading to detection of blood in the stool but no visible melena, and symptom onset is typically slower than in this case.
  3. Gastric cancer: Gastric cancer is most common in elderly men (peak incidence: 70 years), patients with a history of alcohol and/or nicotine abuse, and patients with a diet rich in nitrites and/or salts (e.g., dried, preserved food). Symptoms can include epigastric pain, nausea, melena, and unintentional weight loss, although the condition is often asymptomatic until it progresses to later stages. This patient's weight loss is most likely related to his abdominal pain with eating, which can lead to a decrease in appetite. Moreover, the incidence of gastric cancer is declining in the US. While gastric cancer should definitely be ruled out, it is the least likely of the differential diagnoses here.

Diagnostic studies

Other differential diagnoses to consider

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