Patient with clinical celiac disease mimicking triple-negative essential thrombocythemia.

Platelets are acute-phase reactants, which can be elevated due to a secondary cause or less commonly because of a primary mechanism. Primary disorders include hematological conditions such as myelodysplastic syndrome, acute myeloid leukemia, chronic myeloid leukemia, polycythemia vera, and essential thrombocythemia (ET). Most ET patients have a mutation in the genes regulating thrombopoiesis, JAK2 , CALR , or MPL genes. But 10%-15% of ET patients are triple-negative, where patients have no detectable mutation. We report a young patient with no significant past medical history evaluated for persistent thrombocytosis. She was initially diagnosed as triple-negative ET based on a bone marrow biopsy. She had positive antibodies for celiac disease, and the diagnosis was confirmed by a small bowel biopsy, which is confirmatory for diagnosing celiac disease in adults. We recommend screening triple-negative ET patients for celiac disease before going to more expensive tests.