An 18-year-old Qatari male, presented in with fever of two weeks duration, not associated with chills, rigors or night sweats. He also complained of left sided neck swelling, decrease oral intake and nausea for the past 2 weeks. No complaints of cough, sore throat and no shortness breath. He denied history of contact with sick patient, recent travel, or contact with animals. He reports receiving the first dose SARS CoV2 vaccine (BNT162b2) 10 days before the start of his symptoms. His past history was remarkable for steroid dependent minimal change renal disease diagnosed in 2015. He was treated initially with prednisolone and cyclosporine for more than two years. He also received rituximab three times during 2018 and 2019 for relapse of his disease, however he was in remission for the last two years and not receiving any medications. He was non-smoker and non-alcohol drinker and works as a policeman. Physical examination on admission was unremarkable except for a temperature of 39  C and the presence of multiple tender enlarged left cervical lymph nodes of varying size with the largest about 1.5 cm in diameter.
Laboratory investigation on admission revealed, white blood cells (WBC) 2400/microL ( Neutrophils 1400 /microL, Lymphocytes 800 /microL, monocyte 200 /microL), hemoglobin (HB) 12.9 gm/dL, platelets 102,000 /microL, creatinine 70 micromol/L, CRP 38.4 mg/L, procalcitonin 0.46 ng/ml, ALT 64 U/L, AST 72 U/L, LDH 432 U/L, ferritin 699 microg/L, with negative ANA and normal C3, C4. Serology for HBV and HCV viruses were negative. HIV combo test and HIV PCR were negative. PCR for CMV and EBV were all negative. Blood and urine cultures were also negative. QuantiFERON TB Gold Plus was negative. Nasopharyngeal swab for SARS CoV 2 PCR was negative. Computed tomographic scan for chest and neck revealed multiple left cervical and axillary lymph nodes the largest one in the left supraclavicular region measuring around 10 x 11 mm (Fig. 1). Patient was initially treated with ceftriaxone however it was discontinued later on when the results of blood and urine were reported negative. He received symptomatic treatment with paracetamol and NSAIDS to control his fever. Excisional lymph node biopsy was done. Sections from the lymph node show effaced lymph node architecture by diffuse polymorphic lymphohistiocytic infiltrate with multiple foci of necrosis (Fig. 2). Many immunoblasts and numerous apoptotic bodies were present. Neutrophils were not seen within the necrosis. By immunohistochemical stains, the lymphoid cells are mostly T lymphocytes that are positive for CD3 (Fig. 3) with no apparent marker expression. CD30 is positive in scattered immunoblasts. The residual of B lymphocytes are positive for CD20 (Fig. 4) and other B-cell markers with no apparent marker expression. Ki-67 is positive in approximately 70% of cells. The histiocytes are highlighted by CD163 and myeloperoxidase. Scattered plasma cells are present and highlighted by CD138. Viral immunostains for EBV, HSV-1, HSV-2 and CMV are all negative. Flow cytometry is negative for monotypic B or T cells. T-cell receptor gene rearrangement showed no clonal T-cell receptor rearrangement. These features were consistent with the diagnosis of Histocytic necrotizing lymphadenitis. The patient was discharged home on in good condition.