Lymphopenia in atopic dermatitis patients treated with oral immunosuppressive drugs

Introduction: Oral immunosuppressive drugs are commonly used in the treatment of atopic dermatitis (AD). In patients with autoimmune- and rheumatic diseases, these drugs have been associated with lymphopenia. Lymphopenia is related to an increased risk of opportunistic infections. The incidence of lymphopenia in patients with AD treated with oral immunosuppressive drugs is yet unknown. Objective: To evaluate the occurrence of recurrent lymphopenia in patients with AD treated with oral immunosuppressive drugs and to make recommendations for screening in daily practice. Methods: Patients with recurrent lymphopenia (i.e. >5 times lymphocyte counts below 0.8 × 10⁹/L) during treatment with oral immunosuppressive drugs were included from our immunosuppressive drugs database and further analyzed. Results: A total of 360 AD patients, treated with oral immunosuppressive drugs, were screened. A recurrent lymphopenia during treatment was found in 11 patients. In 8/11 patients, recurrent lymphopenia was observed during concomitant treatment with prednisone. No serious infections were observed. Conclusion: Lymphopenia is occasionally seen in AD patients treat with oral immunosuppressive drugs. Concomitant treatment with prednisone seems to be a risk factor. We suggest to include monitoring of lymphocyte counts in the standard follow-up for all AD patients treated with oral immunosuppressive drugs.