The dermal sinus tract (DST) is an infrequent form of spina bifida occulta that can be complicated by infections. This is a case report of a child with a rare association of DST complications, namely hydromyelia and intramedullary abscess. A 1-year-old male child was admitted to the hospital with a history of fever and progressive loss of lower-limb movements and the presence of an ostium in the midline of the lumbar region and cutaneous stigmas with no secretion discharge. Computed tomography and magnetic resonance imaging (MRI) of the thoracolumbar spine revealed an extensive intradural T12-S1 abscess and cystic dilatation of the central medullary canal (hydromyelia) from T2 to T12. The surgery was conducted with the drainage of the large abscess and also improving hydromyelia. After 30 days of rehabilitation with physical therapy, the child could walk despite right crural monoparesis (possible L4/L5 injury). This report described a case of DST that showed a rare association of two complications, i.e., intramedullary abscess and hydromyelia, due to a late diagnosis. Sequelae could have been prevented with early diagnosis.