Periprosthetic joint infection complicates up to 3% of all arthroplasties. Staphylococcus lugdunensis, although a coagulase-negative staphylococcus, shares adhesins, biofilm formation and tissue-destructive toxins with S. aureus and behaves far more aggressively than other skin commensals, with high relapse rates unless the implant is removed.

What’s more, the cure is harder when the soft-tissue envelope is compromised. Elephantiasis nostras verrucosa is a rare consequence of chronic non-filarial lymphoedema, driven by obesity, venous insufficiency and repeated cellulitis, in which dermal fibrosis and hyperkeratosis leave a fragile limb that both predisposes to infection and hampers wound healing.

Antimicrobial therapy, especially if is a long-term regimen, can be  hazardous: adverse events occurred in 73 of 80 patients in a prospective PJI series. Cotrimoxazole is a well-recognised cause of drug-induced immune thrombocytopenia that can lead to life threatening bleeding symptoms.