Background: Aseptic meningitis has a wide etiology, but the most common cause is viral infections.  The incidence of viral meningitis drops with increasing age.  Clinically, aseptic meningitis presents with the abrupt onset of fever, headache, meningeal signs, photo- or phono phobia and nausea / vomiting.  We present a case of aseptic meningitis with nonspecific presentation in adolescent. 
Case: A 14-years-old boy presented with intermittent headache since 1 month ago, but become more frequent in the last 3 days. He had neither history of vaccination in the near term nor past history of medication.  He was fully alert with normal vital signs, with positive meningeal signs and increased physiological reflexes. The laboratory result showed elevated erythrocyte sedimentation rate, slight hyponatremia and hypochloremia. The head CT-scan was normal. His cerebrospinal fluid was clear, mononuclear cell dominated pleocytosis (300 cells/ml) with normal protein and glucose level. Both the direct Gram and acid fast bacillus smear were negative. He was hospitalized for 3 days with supportive treatment and corticosteroid, and was later discharged with good condition.
Conclusion: Virus infection was suspected as the cause of aseptic meningitis in this patient. Unfortunately the specific etiology cannot be confirmed because of the limited resources. This patient presented with nonspecific symptoms of viral meningitis, with headache as the only complaint without fever. Early diagnosis of aseptic meningitis can decrease unnecessary use of antibiotics. It is important to always rule out meningitis in all patients with headache and positive meningeal sign, even without fever.