Case Presentation: A 50-year-old woman presented with fever two month after returning from Mexico. Three weeks before the hospital admission, a gradual onset of fever occurred, which became increasingly worse and then continuous. She presented to our hospital with a fever of unknown origin after two prior clinics were unable to determine the cause. Of note, the patient had a past medical history of asthma.
On a physical examination, her body temperature was 36.9 °C, blood pressure was 110/74 mmHg, heart rate was 95 beats per minute, respiratory rate was 16/min, oxygen saturation was 97 % on ambient room air, and she had no pain. Abdominal palpation revealed moderate hepatosplenomegaly. There was no lymphadenopathy. The rest of her examination was unremarkable. Laboratory studies revealed elevated levels of lactate dehydrogenase, C-reactive protein, and soluble interleukin-2 receptor. Smears for malaria parasites were negative, and viral serological examinations for Epstein-Barr virus and Cytomegalovirus showed a pattern consistent with prior infection.
After admission to the hospital, her symptoms and laboratory data gradually improved spontaneously, and she was discharged initially with close follow-up as an outpatient.
However, two weeks after discharge, she developed a recrudescence of fever. A bone marrow examination revealed hemophagocytosis. Because intravascular lymphoma (IVL) was considered, random skin biopsies from her abdominal wall were performed, which revealed extensive infiltration of CD20 (+) and CD79a (+) atypical lymphoid cells in the lumen of vessels, which was consistent with the suspected diagnosis. A fludeoxyglucose positron emitting tomography computed tomography scan showed diffuse accumulation in the liver and spleen. This was consistent with spread of the lymphoma to those affected organs.
During six cycles of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) chemotherapy, she achieved complete remission. Subsequently, two cycles of high-dose methotrexate therapy was performed as a prevention of central nervous system invasion.
Discussion: Intravascular lymphoma is a rare and life-threatening illness, so early diagnosis is important. The definitive diagnosis requires histological evaluation of affected organs.
However, unlike many other lymphoma subtypes, the biopsy site is especially important for the diagnosis. In some prior case reports, IVL has been identified in bone marrow, skin, brain, liver or spleen.
Random skin biopsies have apparent high sensitivity when sampled from the trunk, thigh, or lower limbs. Performing skin biopsies is less invasive compared to sampling intra-abdominal organs or bone marrow.
Conclusions: In patients with a fever of unknown origin and a travel history, it is important to think about unusual infectious disease. In addition, one needs to consider common and rare diseases, such as IVL.
For the detection of IVL, random skin biopsies yield a high sensitivity for the diagnosis and should be considered initially, instead of more invasive organ histological sampling.