Differential Diagnosis for a 61-year-old Lady with IBS Symptoms and Elevated DGP IGA
- Single most likely diagnosis:
- Irritable Bowel Syndrome (IBS): The patient's symptoms are consistent with IBS, and the normal TTG IGA levels make celiac disease less likely. However, the elevated DGP IGA suggests some degree of gluten sensitivity, which can coexist with IBS.
- Other Likely diagnoses:
- Non-celiac gluten sensitivity (NCGS): The elevated DGP IGA and IBS symptoms could indicate NCGS, a condition where individuals experience symptoms similar to celiac disease but without the same level of immune system activation and intestinal damage.
- Wheat sensitivity: This condition involves an adverse reaction to wheat that is not related to celiac disease or a wheat allergy. The elevated DGP IGA could be indicative of an immune response to wheat.
- Do Not Miss diagnoses:
- Celiac disease: Although the TTG IGA is normal, celiac disease should not be entirely ruled out without further testing, such as an intestinal biopsy or genetic testing. Some individuals with celiac disease may have normal TTG IGA levels, especially if they have been on a gluten-free diet.
- Small intestine bacterial overgrowth (SIBO): This condition can cause IBS-like symptoms and should be considered in the differential diagnosis, especially if the patient has a history of antibiotic use, gastrointestinal surgery, or other risk factors.
- Rare diagnoses:
- Whipple's disease: A rare, systemic bacterial infection that can cause gastrointestinal symptoms, including diarrhea, abdominal pain, and weight loss.
- Crohn's disease or ulcerative colitis: Although less likely, these inflammatory bowel diseases can cause IBS-like symptoms and should be considered in the differential diagnosis, especially if the patient has a family history, blood in their stool, or other alarming symptoms.