Dr Francis Lai
Monash Medical Centre 

 ABSTRACT

Title: Back Pain And Fever – When The Diagnosis Becomes Crystal Clear

Authors: FYX Lai1, A Chee1, I Jong2, R Junckerstorff1

Affiliation: 
1. Department of General Medicine, Monash Medical Centre, Melbourne, Victoria, Australia
2. Department of Radiology, Monash Medical Centre, Melbourne, Victoria Australia 

Abstract Text: 

Clinical Record
A 61-year-old man presented with acute thoracolumbar back pain and pyrexia. Laboratory findings are described in Table 1. Spinal magnetic resonance imaging (MRI) was suggestive of left L3/4-L4/5 septic facet joint arthritis. CT-guided aspirates from the facet joints revealed no micro-organisms. Prolonged treatment with intravenous ceftriaxone and vancomycin was administered. However the patient remained febrile with episodes of hypotension and tachycardia. 
In an attempt to obtain a microbiological diagnosis, all antimicrobials were ceased. Fevers continued and multiple blood cultures remained sterile (Table 1). 18F-fluorodeoxyglucose positron emission tomography scan demonstrated bilateral joint inflammations suggestive of polyarticular gout (Figure 1). Ultrasound-guided aspirate of the right acromio–clavicular joint revealed monosodium urate crystals. The patient was commenced on colchicine resulting in rapid improvement, normalisation of inflammatory markers and haemodynamic stability. 

Discussion
Gout typically affects the lower extremities, however a recent study suggests axial involvement may be as high as 14%.1 Similar to our case, lumbar facet joints were found to be most commonly affected (Toprover, 2015; Konatalapalli, 2009). Spinal tophaceous gout may be difficult to differentiate from osteomyelitis as their appearances may be similar on MRI and CT (Konatalapalli, 2009).
This case illustrates acute polyarticular gout presenting with back pain and systemic inflammatory response syndrome (SIRS). Polyarticular gout can induce a SIRS response and may be mistaken for sepsis. Multilevel spinal infection is unusual and non-infectious aetiologies should be considered. Given the clinical and radiological difficulty in distinguishing polyarticular gout from infective aetiologies, the importance of examining synovial specimen with polarised light microscopy should not be underestimated.

References
1. Toprover, M, Krasnokutsky, S, Pillinger, MH. (2015). Gout in the spine: imaging, diagnosis, and outcomes. Curr Rheumatol Rep, 17(12):70.
2. Konatalapalli, RM, Demarco, PJ, Jelinek, JS, et al. (2009). Gout in the axial skeleton. J Rheumatol, 36:609–13.