No case of COX-1-related aspirin resistance found in 289 patients with symptoms of stable CHD remitted for coronary angiography.

OBJECTIVE: To assess the prevalence of a lacking aspirin effect on cyclooxygenase-1 (COX-1) ("aspirin resistance") in patients with symptomatic, stable coronary heart disease (CHD) using test methods directly reflecting inhibition of COX-1. MATERIAL AND METHODS: Arachidonic acid (AA)-induced platelet aggregation and plasma thromboxane B2 (TXB2) were determined twice 3 weeks apart - prior to elective coronary angiography - in 289 patients on 75 or 160 mg aspirin daily, all prompted to take aspirin before testing. Subjects who demonstrated lacking any effect of aspirin (>/=20 % AA-induced aggregation) on one or both occasions were later given a third test. Forty-two patients not taking aspirin were used as TXB2 controls. RESULTS: Eleven (3.8 %) had aggregation > or = 20 % in at least one of the two initial tests, but only two on both occasions. During the third test, all 11 patients had aggregation <20 %. The TXB2 distributions in controls and study patients differed markedly (mean 173 versus 19 pg/mL). Taking 45 pg/mL as the TXB2 cut-off level, sensitivity and specificity for detecting subjects taking aspirin were 90 % and 89 %, respectively. The area under the ROC curve was 0.96. CONCLUSION: Repeated AA-induced platelet aggregometry showed that COX-1 could be blocked by low-dose aspirin in all 289 tested patients, suggesting that aspirin resistance is rare in patients with stable CHD.

Persistently elevated levels of von Willebrand factor antigen in HIV infection. Downregulation during highly active antiretroviral therapy.

Levels of circulating von Willebrand factor (vWf) antigen are thought to reflect endothelial involvement in various disorders. In the present study we found markedly elevated plasma levels of vWf in HIV-infected patients demonstrated on both cross-sectional and longitudinal testing. Notably, we found that a persistent rise in vWf antigen was associated with progression of HIV-related disease. This elevation of vWf antigen represented functionally normal vWf as evaluated by plasma FVIII, ristocetin cofactor assay and vWf multimer analyses. While HIV-infected patients showed enhanced platelet activation, platelets did not contribute substantially to the increased vWf levels. The high vWf levels were significantly correlated with high viral load, and during HAART, the pronounced decline in HIV RNA levels was accompanied by a corresponding decrease in vWf. The persistent elevation of functionally normal vWf during HIV infection, most probably reflecting a persistent endothelial cell activation, may have an important role in the pathogenesis of HIV infection.

Tuberculous infection.

A female patient presenting with post-prandial epigastric pain and weight loss was diagnosed to have oesophageal tuberculosis by endoscopic biopsy. She responded well to standard anti-tuberculosis treatment.

Penile implant surgery--local experience with the semi-rigid, single component inflatable and the multi-component inflatable penile prostheses.

A retrospective analysis was performed on 26 men who underwent penile implant surgery using semi-rigid, single component inflatable, and multi-component inflatable penile prostheses over a five-year period. No intraoperative complications were encountered in our series. Major complications following discharge from the hospital were encountered in 6 patients (23.1%). After revision surgery, 4 patients (15.4%) eventually required removal of their penile implants. Good sexual satisfaction was noted in 18 patients (69.2%), while another 2 patients (7.7%) reported fair sexual satisfaction. Six patients (23.1%) expressed dissatisfaction with the procedure.