unsuitable for the creation of an arterio-venous fistula (AVF) or implantable graft. A tunnelled dialysis catheter (Doublelumen PermCath) was inserted and haemodialysis commenced. Two months later he was admitted with pyrexia, rigors and a marked inflammatory response. He also complained of pain at the left sterno-clavicular joint. Repeated blood cultures, from separate sites, grew Staphylococcus epidermidis. Spiral CT scanning demonstrated evidence of osteomyelitis and clavicular destruction. The catheter was removed and peritoneal dialysis commenced. Antibiotic therapy with vancomycin and rifampicin was continued for a 6 week period with resolution of symptoms and inflammatory markers.Case 2. A 62-year-old Yemeni man presented to our emergency department with ESRF. Owing to symptomatic uraemia a tunnelled catheter was inserted and dialysis commenced. Three months later the patient developed high fevers, with raised inflammatory markers. Repeated blood cultures were negative. Despite replacement of the line and empirical antibiotic therapy he developed a shallow 4 cm ulcer at the catheter exit site. The catheter was removed, and the ulcer biopsied. The culture grew fully sensitive Mycobacterium tuberculosis. Clinical and radiological assessment found no other sites of tuberculosis. After initiating treatment and replacing the catheter, the ulcer healed and the patient improved.

The PFA-100 device is increasingly used for assessing platelet function. Its use to monitor anti-platelet therapy, like acetylsalicylic acid (ASA), has been described. In most studies single PFA-100 measurements were used. In this study, we evaluate the influence of ASA on duplicate measurements using collagen/epinephrine cartridges. Twelve healthy volunteers received a single dose of 160 mg ASA and 12 other healthy volunteers received 30 mg ASA during 10 days followed by 80 mg ASA during 10 days. PFA-100 measurements were performed in duplicate 1 and 24 h after the final intake of medication. The mean coefficient of variation of duplicate measurements before medication was 8.4% and at least two times higher after the intake of a single dose of 160 mg ASA or 30 mg ASA during 10 days. Per individual, huge differences between duplicate measurements were observed after ASA ingestion. Differences were less pronounced after ingestion of 80 mg ASA during 10 days, because six of 12 volunteers had a maximum PFA-100 value>300 s in both measurements. As a consequence, one should be cautious to use the PFA-100 to monitor ASA therapy in individual patients.