by Louis P. Theriot, M.D., F.A.A.P.
Published on Feb. 14, 2005
One of the first dictums that is taught in clinical medicine is that appendicitis is the great imitator. While there is a classic presentation for an acute appendicitis, far too often it can be subtle and take on the appearance of something entirely different. That is why clinicians must have a very high index of suspicion when entertaining the diagnosis of appendicitis. The converse, however, is also true. There are a number of illnesses that can look like appendicitis.
I received the call around 2 o’clock a.m. from a concerned mom. Her 18-year-old son was awakened from a sound sleep complaining of severe right-sided pain. She said that he did not have fever, had not vomited or had diarrhea, and was mildly nauseated. When I asked her to press on his abdomen I heard him let out a yelp when she pressed on the right side. Fearing that this could be an appendicitis, I wanted to see him in the office to be sure.
I watched them park and get out of the car. The young man moved very slowly, hunched over to his right side and walking like an old man. It looked as though he had the walk of someone with an appendicitis. Once in the room for the examination he shifted his weight from side to side as if to find a comfortable position. At times he seemed to writhe in pain. Now, this is NOT typical of someone with an appendicitis. They usually want to lie still and not move at all. His temperature was normal which was a bit reassuring. Lying on the examining table he gingerly got into a supine position. He had good bowel sounds, which also goes against an appendicitis. But, he was exquisitely tender in the right lower quadrant of the abdomen, right where the appendix would be. When I gently pressed in this area, he winced in pain. I slowly pressed deeper and deeper which caused increasing discomfort to the patient. When I suddenly lifted my hand off the abdomen he jumped from the pain. This is called rebound tenderness, which can be a sign of an appendicitis.
I told mom that it was suspicious enough for being an appendicitis, and I was going to call a surgeon. But before calling him I needed to do a rectal examination in order to complete my assessment. Her son was none too thrilled. Much to my surprise I found the rectum full of rock hard stool, an incredible amount. After the examination he told me, “Oh yeah, I haven’t gone to the bathroom for a couple of days.” I had mom return to the room and told her I was a bit perplexed. At first I would have sworn that this could have been an appendicitis. But now I wasn’t so sure. Her son interrupted. “Doc, where’s your bathroom?” I motioned to the room across the hall. He said, “I’ll be right back.” I went on to tell mom what the next course of action should be. Fifteen minutes later when we heard the toilet flush, her son came bounding into the room. “Boy, doc. I feel great. Thanks.” His exam was entirely normal and he truly did not have an appendicitis. He was just constipated.
I received a call from a friend about their four-year-old daughter who had had a fever all morning. It was now 3 o’clock p.m. and they were calling because she had right-sided abdominal pain. She had not wanted to eat all day, and had vomited at noon. She had vomited two times and was complaining of pain in her upper abdomen. What prompted them to call was the fact that her temperature was now 102.7 degrees, and the pain was localized to her right lower abdomen.
Being a Sunday afternoon, to expedite things I had them stop by the lab at the hospital for a blood test, and then met them in the x-ray department. I did a cursory exam and it was very consistent with an appendicitis. The lab paged me with the results of her blood test. Sure enough, her white blood count was high, 19,000, which further made the case for an appendicitis. Waiting for the x-rays of her chest and abdomen to be developed, I put in a call for the surgeon. The first film was her chest x-ray. Much to my chagrin, she had a whooping pneumonia in the right lower lung. I apologized to my surgeon friend and told him it was a false alarm. She had a pneumonia caused by a specific bacteria, pneumococcus, which can notoriously mimic appendicitis. The interesting fact was that she did not have a cough or ANY respiratory symptoms. This is not uncommon with this type of pneumonia. Had it not been for the chest x-ray I would have bet that she had an appendicitis. I treated her with antibiotics and she was better in two days.
Jason is a five-year-old who had a similar history as the child mentioned above. His parents, however, took him immediately to the emergency room. His mom is a nurse and, fearing that he could have an appendicitis, she knew that tests would be needed. I received a call from the ER doctor who informed me that Jason had a classic examination for an appendicitis, and that he wanted to call a surgeon. It was interesting that Jason’s white blood count was not elevated, and the ultrasound of his abdomen was not very helpful since the appendix could not be seen.
The surgeon did see Jason in the ER. He was impressed enough with the examination to take Jason to surgery to do a laparoscopic appendectomy. This is a procedure whereby a scope is inserted to visualize the appendix and remove it. The procedure went very well. The surgeon found a perfectly normal appendix, which was removed anyway, and some enlarged and inflamed lymph nodes very near the appendix. Jason had a benign condition called mesenteric adenitis that is caused by a non-specific virus. It causes the lymph nodes within the abdomen to become inflamed, and it can present just like a classic appendicitis. He did fine and left the hospital the next day…never having to worry about having an appendicitis again.
So, while the appendix truly is the great imitator, I could give countless examples of how an acute appendicitis was missed, or when it has confounded the best of clinicians, or looked like and was treated as something entirely different. One must keep in mind that there are a number of conditions that can look like an appendicitis. The bottom line is that one must have a very high index of suspicion when dealing with abdominal pain in a pediatric patient.