Tonsillar abscess formation due to herpes simplex type-1 in a severely immunocompromised stem cell transplant patient with chronic myeloid leukemia.

Herpes simplex virus (HSV) causes life-threatening infections in immunocompromised patients such as transplant recipients and patients with hematologic malignancies. We herein describe the case of a patient with chronic myeloid leukemia blastic transformation who developed severe herpetic tonsillitis complicated by tonsillar abscess formation. Abscess formation was determined by computed tomography, whereas tonsillitis due to HSV was confirmed by pathologic and immunohistochemical examinations of the tonsillar biopsy. For molecular confirmation, HSV DNA was amplified by LightCycler PCR and type (HSV-1) determined by melting point analysis. The patient responded promptly to antiviral treatment and there were no signs of recurrent infection at the follow-up. To our knowledge, this case is unique for being the first case of tonsillar abscess formation due to HSV-1, also emphasizing the importance of herpetic infections in the differential diagnosis of oropharyngeal small-sized lesions in the immunocompromised patient population.