We present a 2 month-old female infant admitted to the hospital with macrocephaly as main clinical sign, irritability, and vomiting. The computer tomography scanning showed a cystic frontal image with contralateral ventricle displacement. Surgical intervention was performed. Purulent material culture was positive for Citrobacter koseri (diversus). Cerebrospinal fluid culture was negative. The infant was treated with antibiotics for 6 weeks with a good outcome. She presented postsurgical hydrocephaly and required ventriculoperitoneal valve.