Association of dengue hemorrhagic fever with multiple risk factors for pituitary apoplexy.

Objective: To describe pituitary apoplexy that developed during the course of dengue hemorrhagic fever.
Methods: We describe the clinical findings, laboratory test results, imaging findings, and clinical course of the study patients.
Results: Patient 1 was a 40-year-old man who developed clinical signs and symptoms of dengue, which was confirmed by serologic testing. He presented with thrombocytopenia and developed severe headache and vomiting. During hospitalization, acromegaly was suspected because of the characteristic disease phenotype. Magnetic resonance imaging confirmed the diagnosis of pituitary apoplexy. Subsequently, the biochemical diagnosis of acromegaly was confirmed, and the patient underwent transsphenoidal surgery. Histopathologic examination showed signs of recent bleeding. Patient 2 was a 38-year-old man with a macroprolactinoma, who had been treated with cabergoline for 10 weeks and had shown improvement on laboratory testing and imaging. The patient then presented with clinical symptoms of dengue (confirmed serologically) and thrombocytopenia. He developed bilateral hemianopsia, and magnetic resonance imaging showed enlargement of the pituitary adenoma with signs of intratumoral bleeding. The patient underwent transsphenoidal surgery, and histopathologic examination documented a pituitary adenoma diffusely infiltrated by blood cells.
Conclusions: We describe dengue as a probable novel condition for pituitary apoplexy because it may be associated with multiple risk factors for pituitary infarction or bleeding. Physicians should suspect pituitary apoplexy in patients with dengue hemorrhagic fever who develop a rapid onset of severe headache and vision defects, even in those without known pituitary adenomas.