Group C Neisseria meningitidis as a Cause of Septic Arthritis in a Native Shoulder Joint: A Case Report

Abstract

Septic arthritis is an Orthopaedic emergency, threatening the joint within hours of onset. Up to 10% of cases of meningococcaemia have an associated septic arthritis. The aetiology of acute meningococcaemia in a variety of clinical syndromes is well documented in the literature. The pathogen Neisseria meningitidis can cause both primary and secondary manifestations of disseminated infection. Broad-range 16S rDNA PCR is a relatively new technique, useful in identifying aetiological agents in septic patients with negative blood cultures. Here, we describe the rare clinical scenario of a 76-year-old woman with primary meningococcal septic arthritis of a native shoulder joint without associated meningococcal bloodstream infection. We discuss the role of 16s rDNA Polymerase Chain Reaction (PCR) in the identification of the infectious agent, Neisseria meningitidis, and the role of this technique in guiding subsequent management.

Figure 1

Anterior-posterior radiograph of the right shoulder at admission.

Figure 2

T2 Weighted MRI Images of the right shoulder taken at 22 hours after presentation, showing early osteomyelitis, bone marrow oedema, bursal collection, and high signal consistent with septic arthritis.

Figure 3

Serum analysis of white cell count and C-reactive protein levels during admission. Antibiotic (ABx) switch at day 10 from Benzylpenicillin and Flucloxacillin to Teicoplanin and Fusidic Acid for presumed MSSA.