Background: Mycosis fungoides (MF) and Sézary syndrome (SS), variants of cutaneous T-cell lymphoma, may arise from antigen-driven clonal expansion and accumulation of helper-memory T cells. Superantigens from Staphylococcus aureus can stimulate T cells.
Objectives: (i) To determine the prevalence of S. aureus carriage in nares and skin in patients with MF/SS compared with historical rates in other conditions. (ii) To determine whether eradication of S. aureus carriage is associated with clinical improvement. Methods Skin and nares cultures were performed prospectively. Patients with positive nares and skin cultures were treated with oral antibiotics and intranasal mupirocin 2% and samples were taken for reculturing at 3 days, 4 weeks and 8 weeks. An exact binomial test was used to compare the carriage rates among different groups.
Results: Among 106 patients with MF/SS, 67 (63%) had skin colonization and 57 (54%) had nasal colonization. Staphylococcus aureus was isolated from 44 patients, 33 (31%) each from skin and nares. Colonization was highest in erythrodermic SS (48%), similar to atopic dermatitis (64%), and lowest in MF without erythroderma (26%), psoriasis (21%), and the general population (10%). Oral and topical antibiotics eradicated S. aureus colonization in nares in 28 of 33 (85%) patients and in MF skin lesions in 30 of 33 (91%) patients at 4-8 weeks, with rapid clinical improvement seen in 58% of S. aureus-colonized patients.
Conclusions: Staphylococcal carriage in nares and skin lesions of patients with MF is similar to that in atopic dermatitis. Eradication of staphylococci from the skin is possible with treatment and was associated with clinical improvement.