**2. How do complex wounds develop in patients receiving hemodialysis?**

Fig. 4. Factors of complex wound development in patients receiving hemodialysis

Chronic renal failure affects practically all the systems of the body, causing neurological, gastrointestinal, cardiovascular, pulmonary, hematological, endocrine-metabolic, and dermatological disorders 7). Among them, cutaneous disorders are one of the common problems in patients on long-term hemodialysis, which may not be only due to renal dysfunction, but may also be due to complications resulting from treatment. The commonest skin disorders are xerosis and pruritus 8, 9). Recent epidemiological studies have demonstrated that the prevalence of pruritus among patients who are adequately dialyzed remains high, ranging between 42 and 75%10-12). Uremic pruritus is very frustrating for patients since no effective treatment for relief of the itching has been demonstrated. The pathophysiological mechanisms of pruritus are mainly unknown, despite several hypotheses being presented 13).

Furthermore, the skin of patients on hemodialysis is dry, and so the skin barrier structure and function are impaired 14). The Observational Dialysis Outcomes and Practise Patterns

The number of patients requiring HD because of obesity-related renal diseases such as diabetes mellitus is increasing 5, 6). This article focuses on the prevalence of complex wounds among patients with chronic renal failure (CRF) undergoing hemodialysis, and shows

We report our 6-year experience involving 30 patients receiving HD who had chronic skin ulcers. In addition, we investigated the differences in characteristics between patients

**Complex** 

**Nutritional factors**  Chronic malnutrition Hypoalbminamia

**Systemic factors** Inflammation, Atherosclerosis Decrease of skin blood flow Immunosupression, chronic anemia, Collagen disease

**Wound**

**Local factors** Xerosis, Pruritus, Infection, Itching, Reduced oxygen, Denervation

Chronic renal failure affects practically all the systems of the body, causing neurological, gastrointestinal, cardiovascular, pulmonary, hematological, endocrine-metabolic, and dermatological disorders 7). Among them, cutaneous disorders are one of the common problems in patients on long-term hemodialysis, which may not be only due to renal dysfunction, but may also be due to complications resulting from treatment. The commonest skin disorders are xerosis and pruritus 8, 9). Recent epidemiological studies have demonstrated that the prevalence of pruritus among patients who are adequately dialyzed remains high, ranging between 42 and 75%10-12). Uremic pruritus is very frustrating for patients since no effective treatment for relief of the itching has been demonstrated. The pathophysiological mechanisms of pruritus are mainly unknown, despite several hypotheses being

Furthermore, the skin of patients on hemodialysis is dry, and so the skin barrier structure and function are impaired 14). The Observational Dialysis Outcomes and Practise Patterns

Fig. 4. Factors of complex wound development in patients receiving hemodialysis

**2. How do complex wounds develop in patients receiving hemodialysis?** 

receiving HD because of DM and those receiving HD due to other diseases.

effective and successive treatments of these wounds.

**Metabolic factors** Disturbed mineral metabolism, Diabetes mellitus, Renal failure, Calciphylaxis

presented 13).

Study, collecting data from more than 29,000 HD patients, showed that 42% of HD patients experience moderate to extreme itching 15). The impaired skin resistance and stimuli caused by scrunching because of itchy skin cause continuous inflammations, which contribute to local skin ulcers and the general development of malnutrition and cardiovascular disease 16). In addition, disturbed mineral metabolism is associated with skin complaints in dialysis patients17). Other cutaneous manifestations include scaling (9.9%), pressure ulcer (2 .0%), and dermatitis (2%) 18, 19).

Regarding cutaneous infection, Bencini *et al.* reported that the incidence of fungal infection in patients undergoing hemodialysis was 67% 20). CRF patients exhibit impaired cellular immunity due to a decreased T-lymphocyte cell count; this could explain the increased prevalence of fungal infections 21). Other cutaneous infections include bacterial (13%) and viral (12%) infections, reportedly common in diabetics 9). Difficulty healing wounds is a frequent problem in patients on HD because of their poor general conditions, including malnutrition, inflammation, and atherosclerosis syndrome 1). Stein and Wiersum, in a retrospective analysis of 22,389 laparotomies, concluded that dysfunction played a significant role in the development and outcome of abdominal wound dehiscence 2). Not only abdominal surgical wounds, but also all surgical sites sometimes develop poor wound adhesion causing a complex ulcer (Figure 5). Mistrík et al. reported at significant decrease in skin blood flow during the HD procedure and concluded that the skin blood flow may be impaired in HD patients, which leads to the development of difficulty in healing skin wounds 3). Consequently, patients with end-stage renal disease were associated with higher resource use, complication rates, and mortality when they were injured 22).

Fig. 5. Development of a complex leg ulcer because of wound dehiscence, following great saphenous vein harvest for vein grafting.
