Why is each answer plausible?
A. Measurement of anti-tissue transglutaminase IgA and total serum IgA
This is a reasonable and non-invasive first step in a patient with persistent microcytic anemia and intermittent gastrointestinal symptoms. Celiac disease often presents with iron-deficiency anemia and can be subclinical. However, it rarely causes acute abdominal pain or subocclusive patterns on imaging. In this case, although celiac disease remains a differential diagnosis, it would not fully explain the radiological findings.
B. Fecal calprotectin and targeted intestinal ultrasound
Crohn’s disease can present with intermittent abdominal pain, subocclusive episodes, and anemia due to chronic inflammation or malabsorption. Fecal calprotectin is a useful non-invasive marker of intestinal inflammation, and intestinal ultrasound is increasingly used in inflammatory bowel disease assessment. While appropriate in certain contexts, these tests may not detect a neoplastic process or mechanical obstruction.
C. Stool culture and ova/parasite testing
Given the recent onset of diarrhea, an infectious etiology is worth considering, especially in younger patients. However, the absence of fever, systemic inflammation, or leukocytosis, along with the presence of anemia and radiological signs of subocclusion, make this option less likely to provide the full diagnostic picture in this case.
D. Discharge with dietary advice and outpatient follow-up
In a patient with resolving symptoms and stable vital signs, this option might seem safe. However, the persistence of unexplained anemia and recent subocclusive symptoms require further investigation before discharge. Premature reassurance could delay the diagnosis of serious underlying conditions.
E. Abdominal ultrasound and CT scan with and without contrast medium
Advanced imaging is fully justified in this clinical scenario. The combination of persistent microcytic anemia, intermittent abdominal pain, and radiological signs of subocclusion raises concern for a possible structural lesion, including neoplasms such as small bowel adenocarcinoma, lymphoma, or GIST. Ultrasound is a low-risk, first-line tool, and CT with contrast offers detailed anatomical information. Even in the absence of classic cancer risk factors, this diagnostic step is appropriate and often decisive.
Outcome
The patient’s wife, who is a physician, questioned the surgical team regarding the lack of investigations to determine the cause of her husband’s abdominal pain and microcytic anemia. She expressed concern that the management was limited to simple observation without any diagnostic workup. She also asked why an abdominal ultrasound had not yet been performed. The surgical team remained convinced that the symptoms were due to a non-specific abdominal colic.
Following his wife’s advice, Lucas decided to leave the hospital. He was discharged against medical advice. The discharge diagnosis was non-specific abdominal colic, and he was advised to rest, maintain adequate hydration, follow a light diet, and undergo outpatient hematologic evaluation to investigate the microcytic anemia.
On 30 July, Lucas underwent an abdominal ultrasound at another facility, which revealed a heterogeneous hypoechoic lesion in the right flank, located at the level of the hepatic flexure of the colon, measuring approximately 5 cm in diameter, with marked vascularization.
On 3 August, a contrast-enhanced CT scan of the abdomen confirmed the presence of a pathological concentric wall thickening (“apple core” lesion) of the hepatic flexure, extending for approximately 5 cm.
On 10 August, a colonoscopy was performed, revealing a stenosing neoplastic lesion at the hepatic flexure, non-traversable by the colonoscope. Biopsies were taken from the lesion.
On 18 August, the patient underwent a laparoscopic right hemicolectomy for colonic adenocarcinoma.
The correct answer is E:
Abdominal ultrasound and CT scan with and without contrast
Despite the patient's young age, lack of family history, and healthy lifestyle, the persistence of microcytic anemia and the subocclusive pattern on abdominal X-ray warranted further investigation to exclude a neoplastic process. Small bowel tumors — including adenocarcinomas, gastrointestinal stromal tumors (GISTs), and lymphomas — may present with nonspecific symptoms such as intermittent pain, bloating, or chronic anemia due to occult bleeding. They are often diagnosed late because early signs can mimic benign or functional disorders.
In this case, abdominal ultrasound was a reasonable and accessible first-line test that could have been performed in the Emergency Department. It is non-invasive, radiation-free, and can detect masses, lymphadenopathy, or wall thickening. However, it may miss deeper or subtle lesions.
CT scan with and without contrast medium remains the gold standard for evaluating structural causes of intestinal subocclusion, detecting intraluminal or extraluminal masses, and assessing surrounding tissue involvement. In this patient, it was the key step that led to the correct diagnosis.
Why cancer should be considered even in young, healthy patients
At first glance, cancer may seem unlikely in a 39-year-old man with a vegetarian diet, no smoking or alcohol abuse, no family history of malignancy, and a physically active lifestyle. However, age is not an absolute protection. Healthy habits reduce risk but do not eliminate it, and persistent symptoms justify escalation. In particular, iron-deficiency anemia in a male patient, combined with signs of partial bowel obstruction, should always raise concern. Even if symptoms resolve with supportive care, the underlying cause must be investigated.