RESUMEN
A temporal lobe abscess was diagnosed in a 57-year-old man. A urethral catheter had been inserted 12â days earlier, just prior to clot evacuation of a subacute haematoma secondary to an arterio-venous malformation. Fever persisted despite debridement and treatment with meropenem and vancomycin. Gram stains of operative samples showed no bacteria. Extended cultures grew pinpoint colonies after 5â days. Meanwhile, sequencing of bacterial 16S rDNA from operative specimens had identified Mycoplasma hominis; the bacterial colonies were subsequently similarly identified. The patient responded promptly following addition of oral doxycycline 100â mg two times per day. There is a growing literature of similar cases. Transient bacteraemia, following urinary catheterisation, with seeding of existing sites of inflammation is the proposed explanation. Urethral carriage of M. hominis is 15% and catheterisation is a common procedure. Mycoplasma hominis maybe more common than appreciated, especially as the need for extended cultures makes a correct diagnosis less likely.