Visceral leishmaniasis is a life-threatening parasitic infection transmitted by sand flies, the symptoms of which can resemble those of systemic lupus erythematosus (SLE). The case concerns a 73-year-old man diagnosed with SLE who was on immunosuppressive therapy and had persistent pancytopenia and an enlarged spleen. Close examination of a peripheral blood smear revealed Leishman-Donovan bodies (parasite amastigotes) in neutrophils, a rare finding because the parasite usually infects monocytes and macrophages. This finding was critical for diagnosis, as traditional methods such as bone marrow aspiration have limited sensitivity for detecting the parasite in peripheral blood. The diagnosis was subsequently confirmed by a combination of bone marrow aspiration and serological testing. The patient's immunosuppressed state probably masked typical inflammatory reactions and increased his vulnerability to this opportunistic infection. The case highlights the diagnostic challenge in differentiating between autoimmune and parasitic diseases, especially in endemic areas where clinicians should routinely check neutrophils for parasites.