Beyond the Usual Suspects: Cytomegalovirus-Induced Hemorrhagic Cystitis in an Immunosuppressed Patient with Lupus Nephritis

Introduction: Infections by cytomegalovirus (CMV) are a well-recognized complication in immunosuppressed patients. However, CMV cystitis is exceedingly rare. We present the case of a patient with systemic lupus erythematosus (SLE) on immunosuppression (IS) who developed gross hematuria from CMV cystitis, highlighting the diagnostic challenges in early detection of this uncommon manifestation. Case Description: A 20-year-old woman with SLE including cardiac involvement and Class V lupus nephritis required IS with steroids, antimetabolites, and anti-CD20 B cell depletion. She presented to a local hospital with abdominal pain, dysuria and gross hematuria. Urine culture was negative. C3 was low, C4 normal, and anti-ds DNA indeterminate. BK virus was negative. Her symptoms were presumed secondary to lupus cystitis, leading to treatment with pulse steroids and cyclophosphamide, which were continued outpatient. She presented to our hospital the next week with fever, abdominal pain, dysuria and worsening gross hematuria with clots. C3 was low with otherwise unremarkable lupus serologies. Given profound IS with unremarkable lupus serologies, concern for opportunistic infection was high. Workup for BK virus, adenovirus, and urinary tuberculosis was negative. Ultimately, cystoscopy with bladder biopsy revealed CMV cystitis (Figure 1). CMV viral load was 2,360 IU/mL. She was started on IV ganciclovir with symptomatic improvement and discharged on oral valganciclovir. Discussion: While opportunistic infections are known causes of macroscopic hematuria in immunosuppressed patients, CMV cystitis is exceedingly rare, with only a few reported cases in the context of hematopoietic stem cell and kidney transplantation. In immunosuppressed patients with autoimmune disease, distinguishing between disease-related manifestations and those due to opportunistic infections can be challenging. Maintaining a high index of suspicion is essential to facilitate early diagnosis and timely intervention in these complex cases.