06/11/2025
UNEXPLAINED WEIGHT LOSS is a SERIOUS SYMPTOM & MUST ALWAYS BE INVESTIGATED
A patient, Ms. AP, a 40-year-old financial analyst, came to my clinic for a second opinion. She had been managing what she called "IBS" (cramping and diarrhea) for months.
"The only good news," she said, "is that I've lost 8 kilos in the last three months. The stress must be burning it off."
This petite lady wasn't dieting. She wasn't exercising more. This was an immediate red flag. Her body was spending energy it didn't appear to have.
My investigation began with an extensive physical examination. She was mildly pale. Her fingernails looked chewed off, brittle and spoon-shaped. All other organ systems were normal.
We proceeded with bloodwork to rule out common systemic causes of weight loss. My first thought went to a metabolic issue, like hyperthyroidism. Her TSH was normal. We also looked for a fuel crisis, like uncontrolled diabetes. Her 75g 2-hour blood sugar was also normal.
Included in her routine labs was the blood count, which provided our next critical clue: Ms. AP had Iron Deficiency Anemia (IDA). Her monthly periods weren't particularly problematic. So this abnormal result became a focusing point in this investigation.
The diagnosis of IBS was likely incorrect. To make this diagnosis, all tests should be normal. A few more tests unraveled the abnormalities. Her C-Reactive Protein (CRP), a marker of inflammation in the blood, came back high. We also checked f***l calprotectin, which measures inflammation inside the gut. It was also significantly elevated.
The picture was now clearer: Ms. AP had active, measurable inflammation in her GI tract, she was anemic, and she was losing weight.
I recommended an endoscopy. Our search started "top-down" with an upper GI endoscopy to check her esophagus, stomach, and the first part of her small intestine. That investigation came up empty; everything looked perfectly normal.
This meant the problem was "downstream." We then proceeded with a colonoscopy. As I advanced the scope, the colon itself was quiet. But the real goal in a case like this is to reach the end of the line—the terminal ileum, where the small intestine joins the large.
As soon as we entered that area, we found the scene of the crime. Her terminal ileum was not healthy; it was severely inflamed, with deep, linear ulcers.
This endoscopic picture, a severely inflamed terminal ileum, immediately brings three primary suspects to mind. The first, and most common in our population, is Gastrointestinal Tuberculosis (GI TB). Another is Crohn's Disease, an autoimmune condition. GI TB is a dangerous mimic, a "great pretender." It can look similar to Crohn's disease. It may sometimes be mistaken for a third and most important suspect, malignancy.
Making this distinction is one of the most critical jobs we have. To miss a malignancy is a crime. The treatment for Crohn's involves suppressing the immune system, which would be catastrophic if we gave it to a patient with an active TB infection.
To solve this, we took several biopsies from the ulcers. We sent them for two separate analyses. The first was to pathology, to look for the classic signs of either malignancy, GI TB, or Crohn's. The second was a TB-PCR test, a molecular test to hunt for the specific DNA of the tuberculosis bacteria.
The results came back after a few days. The TB-PCR test was negative. The pathology, meanwhile, showed all the hallmarks of Crohn's, with no malignant cells seen.
We had our culprit. I sat down with Ms. AP and explained that the "IBS," the anemia, and the weight loss were all part of this one diagnosis: Crohn's Disease. Her immune system was attacking her intestine, preventing her from absorbing food, iron, and calories. The 8 kilos she "lost" was a sign of her body starving.
With the correct diagnosis confirmed, we were able to start her on the proper medication to control the inflammation. Her case is a reminder that unexplained weight loss is not benign and must always be investigated.
CTTO Dr. Carlo Cornejo, Gastroenterologist 🙏
"Your wellness, our passion!" 💗
Diona Reina Jacoba Mabus