In clinical practice, in addition to the treatment of the primary disease, it is particularly important to ensure the patient’s comfort. The skin is the largest tissue and organ of the human body and is easily damaged by external and/or internal factors, resulting in skin wounds. Elderly patients are particularly susceptible to skin damage due to insufficient nutrition and reduced skin elasticity . The presence of skin wounds can cause pain and anxiety in patients, increasing the risk of infection, and even affecting the treatment of the primary disease . Therefore, timely and effective treatment of patients' skin wounds should be prioritised by the healthcare provider.
In this article, the deep foot wound of one patient was caused by an ingrown nail, which damaged the nail groove and adjacent tissues. Crushing injury caused by ingrown toe or fingernails often lead to secondary infection of the subdural hematoma, subsequently evolving into subdural abscesses. Whereas Patient B's wound was due to long-term diabetic hyperglycaemia, aging and other factors that caused the progressive deterioration resulting in a substantial non-healing diabetic foot ulcer with gangrene. The main pathogen of these wounds is typically Staphylococcus aureus . In the case of these patients and for others with infections, antibiotics such as cephalosporin should be considered for use to control the infection while keeping the wound surface clean and dry. In addition, wounds infected by anaerobic bacteria do not need to be bandaged. In typical wound healing of anaerobic bacteria infected wounds, it is necessary to ensure a good external environment interface for the promotion of self-healing and to allow the affected wound to breathe (exposed to oxygen). Purulent wounds will eventually cease to produce discharge and scab over by themselves, forming a natural protective layer without external treatment. However, in the cases reported here, after the application of conventional nursing methods failed to show significant improvement, and based on the pharmacological effect of MTZ against anaerobic bacteria, 0.75% MTZ gel was continuously applied to the wound surface. MTZ gel has the advantages of being affordable and readily accessible to healthcare providers. The simple and convenient local application of MTZ gel can increase the compliance of patients with routine medication use. Patient A's deep foot wound healed completely after 11 days of applying MTZ gel, and patient B's diabetic foot gangrene wound also improved significantly. Taken together these cases supported the effectiveness of MTZ in wound healing, particularly in chronic non-healing and infected wounds.
MTZ gel contains nitroimidazole substances, which are reduced to amino groups in oxygen-free environments . Nitroimidazole groups can also combine with glucuronic acid within the human body to promote metabolism, as well as having a broad-spectrum effect on antibiotic resistant strains of anaerobes and parasitic worms . In clinical practice, MTZ gel is shown to be effective in treating and preventing infections caused by anaerobic bacteria. For example, patients with abdominal respiratory tract or pelvic infections were shown to be treated effectively with MTZ gel . MTZ gel can also play a role in preventing and treating oral anaerobic bacteria infection [8, 17]. The absorption properties of MTZ gel means that the drug can be broadly used throughout the human body; it can directly enter saliva, liver abscesses, or be used to enter cerebrospinal fluid . However, MTZ gel was shown to have no effect on facultative aerobic bacteria growth or aerobic bacterial infections, thus correct diagnosis of infection symptoms should be made prior to the choice of using MTZ gel treatment.
Although our study was limited by the number of patients, it still demonstrated promising results. Simple application of a topical ointment helped to improve the patient's compliance and treatment enthusiasm. In addition to the application of drugs in the treatment process, it is also necessary to keep the wound clean and dry. Due to various factors such as trauma and poor life habits, deep wounds have a relatively high incidence rate, and anaerobic infection caused by deep wounds will seriously affect the prognosis of patients . Diabetic foot, as the main complication of diabetes, is the main reason for the amputation of patients. In addition, diabetic ulcers also cause a huge economic burden on patients, their families and society . If local application of MTZ can cure a considerable proportion of patients, the wound care management process and treatment time may be significantly reduced, without the need for further surgical intervention. In view of the anti-anaerobic effect of MTZ, and its successful application in the cases of foot wounds shown here, MTZ gel may also provide beneficial effects for the enhanced healing of surgical wound infections and anaerobic infections caused by trauma. Therefore, the authors believe that MTZ gel can be extended to the treatment of deep wounds of the feet and the treatment of widespread anaerobic infections, as was the case in the diabetic foot reported here. Although MTZ gel in wound healing was shown to be promising, to form solid conclusions, further research and validation is required. Furthermore, previous literature has reported that a compound MTZ gel containing silver ions or a mixture of metronidazole and iodine was superior to MTZ gel use alone in some respects , which also implicated the use of MTZ and provides new ideas for our future research.