Chest CT scan and laboratory data from the patient. (A) Chest CT scanners of the patient at the start of her respiratory symptoms (left), referral to our center (middle), and 38 days after immunoglobulin replacement therapy initiation (right). (B) Laboratory data. These data were collected in 2024. The patient’s initial blood test for immunoglobulin concentration, performed in December 2023, showed a level of 3.4 g/L. LLN, lower limit of normal. (C) Total serum IgG level and anti-SARS-CoV2 spike IgG level in the patient's serum before and after immunoglobulin replacement therapy initiation. dsDNA, double-stranded DNA; ENA, extractable nuclear antigens; ANCA, anti-neutrophil cytoplasmic antibodies.