Lab Studies:
ED: <br>CBC, CMP grossly normal <br>ESR 63 <br>CRP 4.8 <br>Urine drug screen negative <br>Gram stain of abscess fluid - negative <br>Blood cultures – negative <br> <br>Inpatient: <br>HIV negative <br>fungal serologies negative <br>Tspot – Positive (on hospital day #4) <br> <br>FNA <br>AFB – Positive (hospital day #4) <br>KOH – negative <br>Fluid cultures – negative <br> <br>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. <a href="CaseStudyImages/CS1NotYourAverageBac-235.jpg" title="Case Photo #1" data-lity><b>Case Photo #1</b></a> <br> <br>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. <a href="CaseStudyImages/CS2CS1NotYourAverage-235.jpg" title="Case Photo #2" data-lity><b>Case Photo #2</b></a> <br> <br> <br>CT: <a href="CaseStudyImages/CS3CS2CS1NotYourAver-235.jpg" title="Case Photo #3" data-lity><b>Case Photo #3</b></a> <a href="CaseStudyImages/CS4CS3CS2CS1NotYourA-235.jpg" title="Case Photo #4" data-lity><b>Case Photo #4</b></a> <a href="CaseStudyImages/CS5CS4CS3CS2CS1NotYo-235.jpg" title="Case Photo #5" data-lity><b>Case Photo #5</b></a> <a href="CaseStudyImages/CS6CS5CS4CS3CS2CS1No-235.jpg" title="Case Photo #6" data-lity><b>Case Photo #6</b></a> <br>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. <br>Abscessed was lanced by ED staff, loop placed for drainage <br>Admitted overnight to our inpatient team for further biopsy & treatment of presumed pyogenic osteomyelitis <br>Peripheral blood gram stain/cultures negative. <br> <br>MRI: <a href="CaseStudyImages/CS7CS6CS5CS4CS3CS2CS-235.jpg" title="Case Photo #7" data-lity><b>Case Photo #7</b></a> <a href="CaseStudyImages/CS8CS7CS6CS5CS4CS3CS-235.jpg" title="Case Photo #8" data-lity><b>Case Photo #8</b></a> <a href="CaseStudyImages/CS9CS8CS7CS6CS5CS4CS-235.jpg" title="Case Photo #9" data-lity><b>Case Photo #9</b></a> <br>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. <br> <br>Inpatient admission with initial treatment for osteomyelitis. <br> <br>Interventional Radiology consulted for FNA of abscess during inpatient admission.

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