Background: Tinea corporis is a fungal infection of the skin excluding the face, hands, feet, scalp, nail, or groin. It mostly affects the immunocompromised host. Ocrelizumab (OCR) is an anti-CD20 monoclonal antibody, used to treat multiple sclerosis (MS), and can be associated with a progressive drop in immunoglobulins. Humoral immunity is essential to protect against fungal infections. To our knowledge, there are no published reports of tinea corporis in association with OCR. Objectives: To report two cases of tinea corporis in OCR treated MS patients and review the FDA database. Methods: Details of cases and review of the FDA Adverse Event Reporting System (FAERS). Search terms included: body tinea, ringworm, and tinea corporis in infection and infestations. Other terms included tinea infection, tinea cruris, tinea pedis, onychomycosis, anal tinea, tinea barbae, tinea Blanca, tinea capitis, tinea faciei, and tinea manuum. Results: We report two cases in women in their 30s, with relapsing MS. Case #1 developed tinea corporis with onset 18 months after starting OCR (q6-month dosing). At the time of infection, IgG was 909mg/dL (normal (NL) 700-1600); IgM 28mg/dL (NL 40-230), and IgA 235mg/dL (NL 70-400); total lymphocyte count was 940/mL (NL 1200-3700); CD3+ 874/mL (NL 780-2490), CD4+ 705/mL (NL 410-1540), but CD8+ at 150/mL (NL 230-1090). Despite local and systemic antifungals, recurrent tinea corporis continued for one year. Thus, OCR was stopped indefinitely. Case #2 developed tinea corporis with onset 40 months after starting OCR (q6-month dosing). At the time of infection diagnosis, IgG was 558mg/dL; IgM 7mg/dL; and IgA 71mg/dL; total lymphocyte count was 2270/mL, CD3+ 2020/mL, CD4+ 1589/mL, and CD8+ 409/mL. Treatment with four weeks of ketoconazole failed, but treatment with fluconazole was effective. OCR continued with plans to deescalate. The review of the FAERS revealed no OCR associated cases of tinea corporis. However, we found reports of 2 tinea infections, 1 tinea cruris, 5 tinea pedis, and 13 onychomycoses. Conclusions: Tinea corporis infection in OCR treated patients may indicate the need for de-escalation of therapy. Both cases were treatment-resistant (one recurrent) and were associated with low IgM. One case had lymphopenia and low CD8+ count. We found no reported cases of tinea corporis within the FDA database. We encourage physicians to report infections to raise awareness about the importance of therapeutic monitoring in patients treated with lymphocyte depleting agents.