Comparison of skin and muscle biopsies before and after pentoxifylline treatment in patients with leg ulcers due to deep venous incompetence.

The aim of this study was to understand the possible mechanisms by which deep venous insufficiency and venous hypertension are associated with trophic skin changes and ulceration and to explain the therapeutic effect of Pentoxifylline in patients with leg ulcers due to deep venous incompetence. Twenty patients were included in this pilot study. They were graded into two groups: group 1, included 10 patients (5 F and 5 M) with deep venous incompetence and normal arteries; group 2, included 10 patients (1 F and 9 M) with deep venous incompetence and moderate arterial disease. Skin and muscle biopsies were carried out before and after the oral administration of 1,200 mg of Pentoxifylline daily (400 mg t.d.s). The following parameters were investigated by means of light microscopy and immunofluorescence tests: engorgement of venous stroma; decrease of intimal elastica; hyaline degeneration; floccular degeneration; pericapillary fibrin deposits and fibrin degradation products; inflammation and fat necrosis; myofibril degeneration; fibrous scar; regeneration and reconstitution of muscle fibres. The results indicated that local inflammation at the ulcer's area cause accumulation of white blood cells in the capillaries and the interstitial fluid, where there is also accumulation of fibrinogen. These changes may lead to chronic tissue ischaemia and ulceration. The known favourable effect of Pentoxifylline on red cells and leucocyte function as well as its lowering effect on plasma fibrinogen level, may be responsible for the observed therapeutic effect of Pentoxifylline on venous leg ulcers.

Double-blind randomised clinical trial of pentoxiphyllin in vaso-occlusive sickle cell crisis.

Frequent painful sickle cell crisis leads to a high number of active days lost due to morbidity or mortality. Only one of the specific drugs has been shown to be efficacious in a controlled clinical trial in the USA. The efficacy and the appropriateness of a drug acting on the erythrocytic membrane, pentoxiphyllin, was investigated in a randomised, double blinded clinical trial in the treatment of acute incapacitating crisis. In the 36 patients studied in a rural hospital in Togo (West Africa) where sickle cell disease is frequent (0.51% of all births), the mean (standard deviation = SD) duration of inpatient treatment was significantly shorter in the actively treated group active drug: 77.6 (40.19) hours, placebo: 102.4 (25.31) hours, difference between means: 24.8 (95% confidence intervals (= 95% CI) 2.02-47.5) hours); p = 0.03. This marked effect of active treatment was evident during the first 48 hours only. The suitability of this therapeutic regime within the studied area is discussed.