Demodex positive discoid lupus erythematosus: Is it a separate entity or an overlap syndrome?

Abstract

Discoid lupus erythematosus (DLE) is a chronic inflammatory erythematous skin disease that can be triggered by several factors. Rosacea is another skin disease that causes facial redness and tenderness. Demodex mites have been reported in rosacea and DLE patients commonly in the literature. These two diseases can be seen concomitant, mimic each other clinically and share common possible etiologic factors. To assess demodex mite infestation in both clinical and histopathological findings in DLE patients. We retrospectively evaluated the files of 42 patients with DLE who had been diagnosed DLE based on clinical and histopathological findings between August 2018 and August 2019. Demodex positivity was detected 50% of patients (n = 21). Neutrophile percentages in the dermal and perivascular area were higher in the demodex positive patients (4.43%) than in the Demodex negative patients (2.19%). The intensity of demodex mites correlated positively with dermal neutrophile percentages. ANA was negative in 29 patients (69%) and positive in 13 patients (31%). Anti‐dsDNA was negative in serology and follicular plugging was positive in histopathology in all 42 patients (100%). This was a retrospective study. DLE and rosacea share common features in etiopathogenesis and clinical presentation. Inflammation and exacerbations caused by the demodex mites may increase the clinical severity of DLE. Although the position of demodex mites in DLE etiopathogenesis is not known exactly, the presence of high demodex in DLE patients has been determined. Standard skin surface biopsy can be a routine procedure for the evaluation of DLE patients in daily clinical practice.

The effect of 577‐nm pro‐yellow laser on demodex density in patients with rosacea

“…6 One of the goals of rosacea treatment is to reduce the density of demodex mites. 6,7 The effect on the decreasing of the demodex mite density with pulse-dye laser (PDL) therapy in rosacea patients was evaluated in a study. 7 There is no study in the literature evaluating the effect of the pro-yellow laser treatment on the demodex mite density on the skin.…”

“…Demodex parasites (Demodex folliculorum and brevis) also play a role in the pathogenesis of rosacea. Demodex infestation is thought to cause stimulation of the cell‐mediated immune response and the emergence of inflammatory lesions by breaking down the hair follicle wall 6 . One of the goals of rosacea treatment is to reduce the density of demodex mites 6,7 .…”

“…Demodex infestation is thought to cause stimulation of the cell‐mediated immune response and the emergence of inflammatory lesions by breaking down the hair follicle wall 6 . One of the goals of rosacea treatment is to reduce the density of demodex mites 6,7 . The effect on the decreasing of the demodex mite density with pulse‐dye laser (PDL) therapy in rosacea patients was evaluated in a study 7 .…”

Facial discoid lupus erythematosus during dupilumab treatment for atopic dermatitis

“…4 A recent study revealed that demodex was detected in 50% of DLE patients. 5 As DLE and rosacea have common features in their etiopathogenesis and clinical presentation, inflammation and exacerbations caused by demodex mites may exacerbate the severity of DLE. 5 Interestingly, in our patient's biopsy specimen, demodex mites were found in the follicular infundibulum (Figure 1f).…”

“…5 As DLE and rosacea have common features in their etiopathogenesis and clinical presentation, inflammation and exacerbations caused by demodex mites may exacerbate the severity of DLE. 5 Interestingly, in our patient's biopsy specimen, demodex mites were found in the follicular infundibulum (Figure 1f). Thus, we speculate that reduction of IL-4 by dupilumab caused Th1 and Th17 dominance through Th2 impairment (and demodex mites may have contributed), leading to DLE in our case.…”