Lab Studies:
ED:
CBC, CMP grossly normal
ESR 63
CRP 4.8
Urine drug screen negative
Gram stain of abscess fluid - negative
Blood cultures – negative

Inpatient:
HIV negative
fungal serologies negative
Tspot – Positive (on hospital day #4)

FNA
AFB – Positive (hospital day #4)
KOH – negative
Fluid cultures – negative

TB Sputum cultures: negative x 3

Other Studies:
Spine X-ray noted mild anterior wedging of the T12 and L1 vertebral bodies and was otherwise negative. Case Photo #1

Ultrasound of the area revealed 2 fairly large discrete lumps within the patient's back with no obvious overlying skin erythema or significant tenderness. High-resolution sonography of these lesions demonstrated complex fluid content. The 2 largest components measured roughly 6 x 2 cm and 5 x 2 cm. These collections appeared primarily subcutaneous, however there was an arborizing component piercing the fascia to involve the underlying erector spinae muscle. Case Photo #2


CT: Case Photo #3 Case Photo #4 Case Photo #5 Case Photo #6
This revealed large abscesses (8x5x2cm, 5x7x3cm) superficial to left posterior paraspinal muscles from T10-L2 with small opacities in left paraspinal muscle. Extension into T12-L1 facet joint with evidence of osteomyelitis without extension into spinal canal. No psoas abscess. No diskitis.
Abscessed was lanced by ED staff, loop placed for drainage
Admitted overnight to our inpatient team for further biopsy & treatment of presumed pyogenic osteomyelitis
Peripheral blood gram stain/cultures negative.

MRI: Case Photo #7 Case Photo #8 Case Photo #9
Findings compatible with septic arthritis or osteomyelitis involving the left T12-L1 facet joint, and spinous processes.

Consultations:
ED – patient failed to schedule initial recommended US-guided abscess drainage and presented to ED 2 weeks later with worsened pain. In ED, his abscess was lanced and sent for gram stain and culture.

Inpatient admission with initial treatment for osteomyelitis.

Interventional Radiology consulted for FNA of abscess during inpatient admission.

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