Acute Hematogenous Osteomyelitis Presenting as a "Cold" Rib in a Child.

A "cold" defect or an area of decreased radiotracer deposition is the less common appearance of acute hematogenous osteomyelitis (AHO) on a Tc99 m-methylene disphosphonate (Tc99 m-MDP) bone scan. Group A beta-hemolytic Streptococcus (GABHS) is a significantly less common cause of AHO than Staphylococcus aureus, particularly when the infection involves the pelvis or flat bones such as the ribs. Here, we present a case report of isolated acute "cold" hematogenous osteomyelitis in a rib of a child with GABHS bacteremia that was detected on 99Tc-MDP bone scan, with magnetic resonance imaging correlation, and pathologic confirmation after rib resection.