br Conclusions br Source of financial support or funding

Conclusions
Source of financial support or funding This investigation was supported by the University of Utah Study Design and Biostatistics Center, with funding in part from the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health, through Grant 8UL1TR000105 (formerly UL1RR025764).
Conflicts of interest
Introduction Sarcoidosis is a granulomatous disorder of unknown etiology that may affect nearly every organ system and immunologically is characterized by impaired T-lymphocyte function and cell mediated immunity (CMI). Due to impaired CMI, sarcoidosis may be complicated by infection with intracellular pathogens, e.g., viruses or malignancies, e.g., lymphoma. Importantly, sarcoidosis is an afebrile disorder except for three clinical variants, i.e., Heerfordt's syndrome (uveoparotid fever) Lofgren's syndrome (E. nodosum with bilateral hilar adenopathy) or neurosarcoidosis (basilar meningitis).1, 2, 3 These three sarcoidosis variants aside, the presence of fever with sarcoidiosis is diagnostically problematic, and should prompt a work-up for an intracellar pathogen or lymphoma. In a patient with sarcoidosis, the presence of splenomegaly and a new splenic infarct increased the complexity of the differential diagnosis.
Case 60 year old female was admitted with fevers to 102.5 °F (without chills), night sweats, profound fatigue, and anorexia (fifteen pound weight loss) over the past ten days. Her past medical history was significant only for sarcoidosis. Thirty years ago she developed dyspnea on exertion and then shortness of breath which prompted pulmonary evaluation. She was found to have bilateral hilar adenopathy with parenchymal lung involvement. Lung biopsy showed non-caseating granulomas. Her sarcoidosis has been in remission after treatment with steroids 31 years ago. She is a non-smoker/drinker and is not taking any medications. Excluding sarcoidosis, she had no other medical disorders. Five days prior to admission, she developed LUQ abdominal pain. She was evaluated in the emergency department (ED) for fever and fatigue. Laboratory tests in the ED included a white blood cell (WBC) count of 8.5 K/uL (n = 3.9–11 K/uL), atypical Sodium Danshensu synthesis were 15% (n = 0–5%), lymphocytes were 34% (n = 21–51%), and her platelet count was 149 K/uL (n = 160–392 K/uL), alanine transaminase (ALT) was 43 IU/L (n = ≤ 36 IU/L), aspartate aminotransferase (AST) was 44 IU/L (n = ≤ 39 IU/L) and alkaline phosphatase (AP) was normal. Abdominal CT scan showed hepatosplenomegaly. She was discharged home, but returned to ED 5 days later with persistent fever and the same symptoms. Further laboratory tests included an alanine transaminase (ALT) of 55 IU/L (n = ≤ 36 IU/L), aspartate aminotransferase (AST) of 54 IU/L (n = ≤ 39 IU/L) and alkaline phosphatase (AP) remained normal. Repeat abdominal CT scan showed hepatosplenomegaly with a new large peripheral splenic infarct (Fig. 1). On hospital admission, her physical examination was unremarkable except for hepatosplenomegaly, LUQ tenderness, and a non-tender bruise on left thigh. Importantly, no pharyngitis or adenopathy was present. Admission laboratory tests included a white blood cell (WBC) count of 9.8 K/uL (n = 3.9–11 K/uL), and the platelet count was 134 K/uL (n = 160–392 K/uL). Alanine transaminase (ALT) was 43 IU/L (n = ≤ 36 IU/L), aspartate aminotransferase (AST) was 44 IU/L (n = ≤ 39 IU/L) and her alkaline phosphatase (AP) was normal. Her Mono Spot test was negative. The erythrocyte sedimentation rate (ESR) was 17 mm/h (<30 mm/h) and C - reactive protein (CRP) was 25.36 mg/L (n = < 3 mg/L). Repeat ferritin level was 353 ng/ml (n = 10–187 ng/ml). Angiotensin converting enzyme (ACE) level was 55 U/L (n = 14–82 U/L). Protein C level was 76% (n = 66–158%) and protein S level was 61% (45–139%). Antiphospholipid antibody (APL) and D-dimer levels were negative. Lower extremity ultrasound showed a left lower leg venous thrombosis. CT scan of the chest showed segmental and sub-segmental branches of the right upper and lower lobe pulmonary emboli. Her T-SPOT was negative. Gallium scan showed enhanced uptake in both lungs and liver. Her CMV IgM titer was 7.01 ISR (n = < 1.1 ISR), CMV IgG was 3.49 ISR (n= < 1.1 ISR), EBV VCA IgM titer was 60.9 U/ml (n = < 35.9 U/ml), EBV VCA IgG was 152 U/ml (n = < 17.9 U/ml), and HHV-6 IgM titer was negative (<1:10). EBV VCA IgM was elevated due to CMV cross reacting with EBV since CMV IgM titer was elevated eight times normal while EBV VCA IgM titer was elevated three times normal. Expectedly, her EBV viral load (quantitative DNA PCR) was negative. Diagnosis of CMV infectious mononucleosis was further supported by an elevated CMV viral load (quantitative DNA PCR) of 1827 copies/ml (n = negative). She gradually improved during her hospital course with resolution of fever, night sweats, fatigue, and LUQ abdominal pain.