Mother replies,
"The diarrhea comes and goes. Sometimes it's there for less than a day, sometimes a few days. It's been happening on and off for most of the past year."
This type of episodic diarrhea that the patient says is the same process repeating itself makes a bacterial cause much less likely. However, it still could be explained by a recurrent virus, or a parasitic infestation, or by a functional problem.
Mother replies,
"I'm so worried that I don't know what to do. Taxes are due in a few days, and I'm afraid to let my husband see the final numbers. I don't want him to start drinking again! He has told me that every time he looks at our daughter, he feels like he should have been able to do something to prevent her pregnancy. She's due in a month, and wants to drop out of high school to raise the baby. How can I get her to see what a mistake that would be? The only good news lately is that my mother is recovering nicely from her surgery."
Whew! Just a few stressors! Certainly there is enough going on in this family to cause a flare of an inflammatory or irritable bowel. We haven't ruled out infectious causes, but they are now less likely, given the time course and the family situation.
Mother replies,
"No, I don't get nauseated with it. Just bad cramping right before the diarrhea hits."
Irritation of the bowel by infection, inflammation, or stress can cause crampy pain and diarrhea. Lack of nausea and vomiting makes acute infection less likely.
Mother replies,
"You'd think that I would have lost weight with all the diarrhea. No, I really haven't changed all that much."
This implies a chronic process for which she has compensated well in her caloric intake.
Mother replies,
"No! I never drank much, but since my husband has been in treatment, I don't drink at all."
It is worth asking, as alcohol can be an irritant. Just because one spouse is in treatment, doesn't mean that the other spouse abstains as well.
Mother replies,
"That crampy abdominal pain seems to happen all over. It's especially bad on the lower left side of my belly. But I feel it in other parts of my belly as well."
Where the patient feels the pain can help determine the cause. It is important to remember, however, that the abdomen also refers pain (remember the periumbilical pain in appendicitis?) In general, pain from the colon is perceived around the "edges" of the abdomen, while small intestinal pain is often perceived in the middle of the abdomen. Pain that moves around indicates that there is more than one part of the intestine involved.
Mother replies,
"No, no travel in nearly a year. We take our vacations in the summer with the kids. Last summer we only went to Canada."
That means that most parasites are now much less likely. Giardia, however, can give intermittent diarrhea like this, so it remains a possibility.
Mother replies,
"Sure, I love milk. I have it every day on my cereal, and try to get another glass in during the day sometime. The calcium is good for me, isn't it?"
Lactose intolerance is a problem that many adults develop over time. It can strike at any age, whenever the body decides to stop making lactase. Since this patient is drinking milk constantly but having symptoms only intermittently, this is not a likely cause.
Mother replies,
"Not in my immediate family, no. My mother tells me that her sister used to get diarrhea like this years ago, but she got over it. I wish I knew how she did it!"
Inflammatory bowel disease tends to run in families, so a family member with the problem makes either more likely. The relationship is not totally clear, however, and probably represents incomplete penetrance of a sort. Irritable bowel syndrome most likely represents an increased sensitivity of the bowel nervous system to stress. Instead of getting "stress headaches" or developing an ulcer, people with IBS get bowel symptoms.
Mother replies,
"The diarrhea is watery, with bits and pieces of stool and lots of gas. I haven't noticed any blood or black stool."
The diarrhea so far does not sound like that associated with malabsorption. This could represent a secretory diarrhea, or a functional one. No blood makes inflammatory bowel disease less likely, although the blood may be microscopic initially.
Mother replies,
"No, I never get a fever with this. It's different than when I get the stomach flu - I get a fever with that!"
Infectious causes are less likely with no fever, except for some parasites. The fact that she can tell the difference between a viral gastroenteritis and this diarrhea also makes infections less likely. Flares of inflammatory bowel disease often have a fever, so that makes this diagnosis less likely.
Mother replies,
"Well, actually, in college I would get so upset about exams that I would have to run to the bathroom several times during the exam. It got so bad that I was suspected of cheating once! But it hasn't happened since!"
Irritable bowel syndrome can start in childhood or adolescence with "butterflies" in the stomach, and often in retrospect can be traced over years by the patient. This makes a functional cause much more likely.
Mother replies,
"Well, this is going to sound silly, but I know colon cancer runs in families - could I have cancer like my mother?"
Not a silly question at all. It is very important to ask the patient what they are worried about, or they may leave the encounter with a great deal of information but not feeling any better. Colon cancer does, indeed, run in families, and when this patient reaches 50, she will need to be screened for it. Colon cancer seldom presents with diarrhea, so this is less likely to be her problem at the moment.
Mother replies,
"I tried it in high school, but my father died of lung cancer from smoking, so I was scared to do it. Turned out to be a good thing, right?"
Not smoking is definitely a good thing. Kids learn from infancy to associate mom and dad (good things) with smoking, so trying to get them not to smoke as teens becomes even more difficult.
Mother replies,
"It's really got worse a few weeks ago. It was so bad that I couldn't be with my mother right before the surgery. Thankfully, she did fine."
Interesting. Her latest flare coincides with her mother's diagnosis of colon cancer and her surgery. It would be very helpful to try to connect other episodes with other crises. If this pattern bears out, infectious causes are even less likely. IBD and IBS can both be precipitated by increases in stress.
Mother replies,
"No, once I am able to fall asleep, I am fine until the morning. About a half hour after getting up in the morning it starts up again if it is going to bother me that day."
Infectious causes seldom respect the desire to sleep.
Mother replies,
"I take the birth control pill you prescribed every day. I did wonder if that was it, but it seems to come at different times of the cycle, and sometimes there is no diarrhea for an entire month."
Being a good detective is always helpful. This patient has already discovered that there is no consistent pattern between the birth control pill and the diarrhea, so she is probably correct in saying that they are not related. Birth control pills seldom cause diarrhea, although nausea is common.
Mother replies,
"I sometimes take Kaopectate, and it works, but it tastes so terrible that it's hardly worth it! Pepto Bismol makes me throw up."
Well, she's right - Kaopectate has the consistency of watery chalk, which is basically what it is. And not being able to tolerate Pepto Bismol isn't that uncommon. The fact that the Kaopectate works is helpful. Inflammatory bowel disease would not respond to Kaopectate except in the extremely early stages. Since she has had this before, this seems unlikely.
Mother replies,
"Funny thing, but the only thing that makes the cramping better temporarily is to go to the bathroom. It seems to settle down for a few minutes before starting up again."
This is typical of irritable bowel, but the exact reason is unclear.
Mother replies,
"Sometimes. I wish my gut would make up it's mind! I'm either stopped up or have the runs. It's really maddening!"
This is typical of irritable bowel also, rather than inflammatory bowel disease. The exact reason for this is not clear.