A 51-year-old gentleman presented to a rheumatologist with a 3 week history of fevers, diarrhea, arthralgias, and generalized pruritis. Blood work revealed mild anemia (hemoglobin 13.5 g/dL). The erythrocyte sedimentation rate (ESR) was within normal limits.Given the acuity of onset, rash, and arthralgias, parvovirus B19 was suspected. Cytomegalovirus, Epstein Barr virus, adenovirus, and coxsackievirus were also possible given these presenting signs and symptoms. Systemic lupus erythematosus, rheumatoid arthritis, adult onset Still's disease, or another connective tissue disease could not be excluded. A reactive gastrointestinal disorder was less likely, but possible considering the history of diarrhea.Over the following 2 weeks, the patient's clinical condition deteriorated and he presented to an emergency department. His temperature was 99.5 degrees Fahrenheit and his pulse was 115 bpm. All other vital signs were within normal limits. The physical examination revealed a lacy macular rash over the arms and anterior chest wall. There was no palpable lymphadenopathy or organomegaly.The patient reported a 3 week history of weight loss, but denied chills or night sweats. He had no risk factors for human immunodeficiency virus infection (HIV) or hepatitis. Travel history included trips to Cuba in the year preceding presentation.Laboratory testing revealed elevated liver transaminases (aspartate aminotransferase (AST) 69 U/L, alanine aminotransferase (ALT) 182 U/L, gamma glutamyl transferase (GGT) 95 U/L), and evidence of systemic inflammation (C-reactive protein (CRP) 64 mg/L, ESR 25 mm/hr, ferritin 328 lg/L). Serum lactate dehydrogenase (LDH) (357 U/L) and bilirubin were elevated (total bilirubin peaked at 92 lmol/L, direct at 92 lmol/L). A complete blood count at admission to hospital revealed hemoglobin of 11 g/dL (Mean corpuscular volume (MCV) 86 fL), platelets of 69 3 10 9 /L, and a white blood cell count of 2.3 3 10 9 /L, with a normal white cell differential.The patient looked distinctly unwell, with new pancytopenia, hyperbilirubinemia, elevated liver enzymes, and signs of systemic inflammation. Infection was suspected, but in the absence of intravenous drug use, high risk sexual behavior, or blood transfusions, HIV, or hepatitis was unlikely. With no history of immunosuppression or evidence of pulmonary pathology cytomegalovirus infection was improbable. Bacterial infections, including Streptococcus pyogenes, syphilis, bartonella, or mycobacteria were considered. The presenting symptoms were not characteristic of a specific connective tissue disease.Microbiologic cultures from blood, urine, and cerebral sinus fluid were negative for bacteria, fungi, and acidfast bacilli. Immune serology including antinuclear antibody, double stranded DNA, perinuclear antineutrophil cytoplasmic antibody, cytoplasmic antineutrophil cytoplasmic antibody, anti-smooth muscle, and assays for extractable nuclear antigens (anti-Ro, anti-La, anti-Scl-70, and anti-Jo-1 antibodies) were normal. Complement levels were decreased (C3 5 0...