Complicated Pyelonephritis Leading to Vertebral Osteomyelitis: Diagnostic and Therapeutic Considerations

This case illustrates the significant progression of pyelonephritis to vertebral osteomyelitis secondary to <i>Escherichia coli</i> bacteraemia, highlighting the potential for hematogenous dissemination from urinary tract infections to the spine. A female patient in her 60s initially presented with fever, nausea, and diarrhoea, subsequently diagnosed with <i>E. coli</i> bacteraemia from pyelonephritis. Despite initial clinical improvement with intravenous and oral antibiotics, her condition deteriorated over three hospital admissions, progressing to L1/L2 vertebral osteomyelitis complicated by bilateral psoas and epidural abscesses. Her functional status markedly declined from independent ambulation to requiring assistance for mobilization. This case emphasizes critical lessons regarding the complexity of determining optimal antibiotic therapy duration, especially when complicated by abscess formation and recurrent bacteraemia. It further underscores limitations associated with early transitions from intravenous to oral antibiotics in complicated vertebral infections, advocating heightened clinical vigilance and a multidisciplinary approach to prevent diagnostic delays and severe functional impairment.