Two cases of intervertebral disk infection in 2 3-year-old boys are presented. The study reported on the anamnesis, clinical, laboratory and instrumental findings as well as therapy in both cases. Diagnosis was suspected on the basis of pain, refusal to assume any position that flexes the spine and irritability. Low-grade fever, the moderate increment of inflammatory indexes and the characteristic changes seen in 1 case on Magnetic Resonance Imaging (MRI) only and in the other one on both Technetium 99m polyphosphate bone-scanning and MRI verified the clinical diagnosis. Furthermore the authors briefs discuss the differential diagnosis of disc-space inflammation and several acute and subacute diseases of infancy and childhood some of them not localized in the spine (myopathy, appendicitis, peritonitis, urinary infections) for which discitis may be often mistaken.