Case Presentation: An 86-year-old female presented with generalized weakness, nausea and shortness of breath. She had a one-year history of mantle cell lymphoma in remission for which she finished 6 cycles of Rituximab with Bendamustine followed with 9 months of Ibrutinib. Her labs showed abnormal liver enzymes and abdominal imaging revealed a 4.2cm left renal mass concerning for malignancy. Further imaging studies for staging revealed multiple enhancing lesions with vasogenic edema in her brain and multiple nodules in her lungs which bolstered the suspicion for metastatic renal cell cancer. Kidney biopsy was negative for malignancy but showed purulent inflammation and necrosis. She was discharged home but was quickly readmitted with sepsis. Blood cultures from her previous admission were positive for Nocardia species (eventually determined to be Nocarda cyriacigeorgica) and repeat renal biopsy was consistent with Nocardia. She finished an inpatient 3-week course of bactrim + imipenem + amikacin and was discharged on bactrim and linezolid per culture sensitivities. On discharge, her imaging showed stable lesions in her brain, lungs and left kidney but she eventually succumbed to her illness.
Discussion: Involvement of two non-contiguous organs, as seen in our patient, denotes the disseminated form of nocardiosis. Clinical presentation varies and can be subtle, often mimicking malignancies. CNS involvement and Nocardia bacteremia have worse outcomes. Treatment is multi-phased, consisting of an induction phase followed by a maintenance/consolidation phase. Duration of treatment is guided by the severity of disease and condition of the immune system. In cases where there is no radiographic improvement of CNS lesions, surgical intervention might be required.
Conclusions: Disseminated nocardiosis often mimicks metastatic malignancy and a high degree of clinical suspicion is paramount in making an accurate diagnosis.
