Cytomegalovirus (CMV) infections acquire characteristics of special severity when they occur in patients suffering primary or secondary cellular immune depression. We present a case of pneumonia with fatal evolution caused by CMV, in a female patient suffering systemic lupus erythematosus. The underlying disease, of recent onset, presented multiorgan involvement (skin, joints, kidney, blood) which could be controlled with steroids and azathioprine. The patient presented a few days after she had overcome an acute outbreak of the disease, a febrile status with rapid evolution with a diffuse pulmonary interstitial infiltrate. Circulating anti CMV antibodies were detected, of IgM class, by a enzyme-immunoassay. The necropsy showed a multiorgan infiltrate (liver, lung, skin, kidney) with cells containing cytomegalic inclusion.