Abstract
Oropharyngeal disease with underlying hematologic disease is commonly seen in daily clinical practice, and may manifest as oropharyngeal bleeding or inflammatory features. In cases with underlying hematologic disease, exacerbation of inflammation from leucopenia and bleeding diathesis from thrombocytopenia are prominent oropharyngeal findings, and blood tests often reveal the underlying disease. Leukemia, particularly acute promyelocytic leukemia （APL）, can be complicated by disseminated intravascular coagulation （DIC） leading to bleeding such as intracranial bleeding. Thus, early diagnosis and treatment can greatly influence prognosis.
We report the case of a 20-year-old man who presented with left buccal phlegmon. Blood testing revealed leucopenia and thrombocytopenia of 3,000/μL and 43,000/μL, respectively, with elevated CRP, FDP, and D-dimer of 12.56mg/dL, 167.6μg/mL, and 34.4μg/mL, respectively. The elevated FDP and D-dimer levels implied DIC due to severe inflammation, but local findings did not suggest any severe infection that could cause DIC; the elevated D-dimer strongly suggested DIC associated with acute leukemia. The severe thrombocytopenia was suggestive of APL, which would require emergency management. He was thus referred urgently to the hematology department on the night of presentation where a definitive diagnosis of APL was made, allowing early treatment.
