A Case of Lumbar Spinal Epidural Abscess and Facet Joint Septic Arthritis Caused by Haemophilus influenzae in an Immunocompetent Host

<b>Background:</b><i>Haemophilus influenzae</i> rarely causes spinal epidural abscess or septic arthritis of the facet joints. We report a case of lumbar spinal epidural abscess and facet joint septic arthritis caused by <i>H. influenzae</i> in an immunocompetent host. <b>Methods</b>: A 53-year-old female patient with lumbar spine disc herniation presented with lower back pain 5 days before admission. <b>Results</b>: The patient was diagnosed with an epidural abscess at the right posterolateral aspect of the lumbar spine at the L4-5 level, as well as facet joint septic arthritis at the right L4-L5 and L5-S1 levels. The patient had no neurological deficit. On the 2nd day of hospitalization, the patient underwent decompressive laminotomy and posterior instrumentation. <i>H. influenzae</i> was identified in the blood cultures. She was prescribed intravenous ceftriaxone for 11 days until discharge and levofloxacin for 76 days after discharge. The patient recovered without neurological sequelae. <b>Conclusions</b>: This case represents the first report of septic arthritis of the facet joint and indicates that <i>H. influenzae</i> is a rare pathogen of spinal infection but can lead to a spinal epidural abscess, irrespective of the host's immune status.