Clinic-epidemiological evaluation of ulcers in patients with leprosy sequelae and the effect of low level laser therapy on wound healing: a randomized clinical trial

Abstract

Background: Mycobacterium leprae is the only pathogenic bacteria able to infect peripheral nerves. Neural impairment results in a set of sensitive, motor and autonomic disturbances, with ulcers originating primarily on the hands and feet. The study objectives were to analyze the clinic-epidemiological characteristics of patients attended at one specialized dressing service from a leprosy-endemic region of the Brazilian Amazon and to evaluate the effect of low level laser therapy (LLLT) on wound healing of these patients.

Methods: Clinic-epidemiological evaluation of patients with leprosy sequelae was performed at the reference unit in sanitary dermatology of the state of Pará in Brazil. We conducted anamnesis, identification of the regions affected by the lesions and measurement of ulcer depth and surface area. After that, we performed a randomized clinical trial. Fifty-one patients with ulcers related to leprosy were evaluated, twenty-five of them were randomly assigned to a low level laser therapy group or a control group. Patients were treated 3 times per week for 12 weeks. Outcome measures were ulcer surface area, ulcer depth and the pressure ulcer scale for healing score (PUSH).

Results: Ninety-seven ulcers were identified, with a mean (SD) duration of 97.6 (111.7) months, surface area of 7.3 (11.5) cm2, and depth of 6.0 (6.2) mm. Statistical analysis of the data determined that there were no significant differences in the variables analyzed before and after treatment with low level laser therapy.

Conclusions: Ulcers in patients with leprosy remain a major source of economic and social losses, even many years after they have been cured of M. leprae infection. Our results indicate that it is necessary to develop new and more effective therapeutic tools, as low level laser therapy did not demonstrate any additional benefits to ulcer healing with the parameters used in this study.

Trial registration: The trial was registered at ClinicalTrials.gov as NCT00860717.

Figure 1

Anatomic distribution of the ulcers on the plantar region. Of 51 plantar ulcers, 33 were on right feet and 18 were on left feet. Ulcers were more common on the areas of the sole that bear weight during walking and standing. The little black circles indicate isolated lesions that were not included in the pictured percentages.

Figure 2

Examples of ulcers in patients with leprosy. (A) Blister formed after walking long distances that later became an ulcer. (B) Fissure on the base of the second toe of the right foot. (C) Right medial malleolus ulcer from a patient with leprosy and HBP. (D) Plantar ulcer on the region of second metatarsal head. (E) Myiasis in a chronic leg ulcer. (F) Chronic ulcer on a lower limb stump.

Figure 3

Flow of participants through the trial.