A Rare Streptomyces griseus Infection of the Sacroiliac Joint: A Case Report.

A previously healthy 26-year-old female presented with one month of worsening low back pain radiating to the right lower extremity. Magnetic resonance imaging (MRI) without contrast of the lumbar spine demonstrated enhancement of the right sacroiliac joint. Sacroiliac joint aspiration followed by culture and microbiology revealed Streptomyces griseus as the cause of infectious sacroiliitis. Streptomyces griseus is a part of the normal human flora that produces a plethora of secondary metabolites applied in various medications such as streptomycin. This represents the first described case of infectious sacroiliitis due to Streptomyces griseus in the literature. It is critical for spinal surgeons to consider fastidious organisms, such as Streptomyces griseus, on the differential diagnosis of sacroiliac joint pain, especially in patients with systemic symptoms and elevated inflammatory laboratory markers.