RESUMEN
This study investigated the mechanism of action and efficacy of CO2 laser rays and hypertonic sodium chloride (NaCl) with different concentrations in treatment of cutaneous leishmaniasis (CL) as assessed clinically, parasitologically, histopathologically by light & transmission electron microscopy (TEM) and immunologically by RT-PCR for gene expression of interleukin-13 (IL-13). Eighty mice were divided into four groups. The first was non infected control group (n=16) and the second was infected and served as non-treated control (n=16). The third (n=32) and fourth groups (n=16) were subjected to NaCl injection and CO2 laser respectively. Results showed that clinical healing by CO2 laser were nearly similar to normal appearance, but differed according to concentration of NaCl, as confirmed by ultrastructure and immunohistopathologic features of the host cells and surrounding skin tissue. IL-13 mRNA was significantly decreased after treatment denoting that Th2 cytokine (IL-13) is important for the development of strategies to prevent the induction of pathologic processes. It is concluded that CO2 laser then 7% NaCl are good modalities for CL treatment and is recommended wherever possible.