White cells, skin blood flow and venous ulcers

Morphological Changes in Lipodermatosclerosis and Venous Ulcers: Light Microscopy, Immunohistochemistry and Electron Microscopy

Objectives:

To demonstrate morphological changes in lipodermatosclerosis (LDS) and venous ulcers by histology, immunohistochemistry, electron microscopy and immunoelectron microscopy.

Design:

Single patient group study in patients with trophic skin changes in chronic venous insufficiency.

Setting:

Department of Dermatology, Medical University of Lübeck.

Patients:

Ten patients with venous leg ulcers.

Interventions:

Biopsies were taken from areas of LDS and compared with clinically normal-appearing skin of the affected leg and with ulcer tissue.

Main outcome measures:

Comparison of the morphological features on light and electron microscopy.

Results:

Superficial dermis. Histologically, the ulcer tissue and LDS skin show dilated tortuous vessels in a glomerulus-like arrangement in the superficial parts of the dermis. Ultrastructurally, the superficial vessels are surrounded by a cuff, which contains amorphous and basal membrane material and is most pronounced in LDS. Immunofluorescence studies reveal ill-defined perivascular staining after incubation with antibodies against fibrin(ogen), laminin and type IV collagen. The exact ultrastructural localization of type IV collagen within the perivascular cuff is observed by immunoelectron microscopy. Deep dermis. In deeper parts of the dermis, the vessels of both ulcer tissue and LDS are surrounded by cellular cuffs with pericytes, fibroblasts and compact collagen bundles.

Conclusions:

We suggest that the severe morphological changes in LDS and ulcer tissue play an important role in the pathogenesis of venous ulceration.

Erysipelas-like inflammation following breast surgery

Impaired lymph drainage is an inevitable consequence of any form of surgery that disrupts lymphatics, resulting in a degree of lymphoedema that may vary from subtle to dramatic and although classically involving an entire limb, may be more localised, confined to only a small area such as a skin flap. Infection is a well-recognised complication of lymphoedema. However, not all inflammatory episodes occurring in the setting of lymphatic dysfunction can be clearly attributed to infection as this article demonstrates. Five patients presented over a 5-year period with distinctive erysipelas-like inflammation affecting the breast which occurred several weeks following reduction mammaplasty in four patients and breast reconstruction in one patient. No clinical response was obtained with standard antibiotics. This inflammatory problem may represent a previously unreported complication of breast surgery with an incidence of 4% following reduction mammaplasty. Recent research supports the notion that this type of episode is most likely to be due to a non-infective inflammatory process related to lymphatic dysfunction induced by surgery.

The use of intermittent pneumatic compression in venous ulceration

Even with the application of four-layer bandaging, the recommended treatment for venous leg ulceration, patients with reduced mobility have delayed ulcer healing. Intermittent pneumatic compression (IPC) has an established role in deep vein thrombosis prophylaxis and has been shown to influence fibrinolysis, tissue oxygenation, oedema and venous return. It has also been suggested, but not yet proven, that IPC may improve the healing of venous leg ulcers. An extensive review of the literature has demonstrated that the use of this treatment on patients with reduced mobility has not been previously studied; yet, analysis of difficult-to-heal ulcer patients would indicate that this method of treatment may be appropriate and requires further study.

Pentoxifylline

Pentoxifylline (oxpentifylline) is a methylxanthine derivative with potent hemorrheologic properties. In the United States it is marketed for the treatment of intermittent claudication. Human and animal studies have shown that pentoxifylline therapy results in a variety of physiological changes at the cellular level, which may be important in treating a diverse group of human afflictions. Immune modulation includes increased leukocyte deformability and chemotaxis, decreased endothelial leukocyte adhesion, decreased neutrophil degranulation and release of superoxides, decreased production of monocyte-derived tumor necrosis factor, decreased leukocyte responsiveness to interleukin 1 and tumor necrosis factor, inhibition of T and B lymphocyte activation, and decreased natural killer cell activity. Hypercoagulable states improve through decreased platelet aggregation and adhesion, increased plasminogen activator, increased plasmin, increased antithrombin III, decreased fibrinogen, decreased alpha 2-antiplasmin, decreased alpha 1-antitrypsin, and decreased alpha 2-macroglobulin. Wound healing and connective tissue disorders may respond to an increase in fibroblast collagenases and decreased collagen, fibronectin, and glycosaminoglycan production. Fibroblast responsiveness to tumor necrosis factor is also diminished. Potential medical uses of pentoxifylline are reviewed.

Absorption of the stable prostacyclin analogue iloprost through the ulcer base in chronic venous insufficiency

Iloprost, a stable prostacyclin analogue, is known to have beneficial effects on the disturbed microcirculation. To develop a topical application for venous leg ulcers it is necessary to know the extent to which iloprost might be absorbed through the ulcer base. The aim of this study was to measure the absorption kinetics of iloprost solutions in increasing concentrations and doses (0.004% [15 micrograms]-0.006% [30 micrograms]) in 23 patients. There was considerable variation amongst the patients in the amount of iloprost absorbed. In 40% of patients no iloprost could be detected in the plasma, whereas in others up to 82% of the iloprost applied was absorbed through the ulcer base. High iloprost plasma levels provoked flushing in two patients. The highest plasma levels were always reached during the first hour after application. There was no direct relation between the ulcer size and the amount of iloprost absorbed. Iloprost concentrations up to the highest concentration applied (0.006%) were well tolerated locally.