Good's syndrome and COVID-19: case report and literature review.

Background: Good's syndrome (GS) is an adult-onset acquired immunodeficiency, in which patients present with thymoma and hypogammaglobulinemia (HGG). GS is characterized by low to absent peripheral B cells and impaired T-cell mediated immunity, often resulting in various (opportunistic) infections and concurrent autoimmune disorders. In this case report, we present a case of a patient with GS and coronavirus disease 2019 (COVID-19) infection after surgical removal of a thymoma. The simultaneous occurence of these two entities is extremely rare. Case Description: A 55-year-old man presented with oral lichen planus and cutaneous lesions. Additional symptoms included a weight loss of 5 kilograms in the last six months. Computed tomography (CT) and positron emission tomography (PET) of the chest showed a large anterior mediastinal mass with a maximum diameter of 10 centimetres. A core needle biopsy was performed, which led to a pathological diagnosis of thymoma type AB. In addition to these earlier findings, laboratory analysis revealed HGG. The combination of a thymoma and HGG led to a diagnosis of GS. Induction chemotherapy with cisplatin-etoposide was started, however, the patient developed COVID-19 after 2 cycles. Treatment with remdesivir was initiated and, subsequently, a thymectomy via sternotomy was performed. Final pathology confirmed a thymoma type AB of 14 centimetres, fully encapsulated, and without invasion. Resection margins were negative and the tumour was classified as pT1aN0, R0 resection. The patient has received immunoglobulin treatments every 4 weeks for his GS and has not developed any new infections since the start of this therapy. Conclusions: Patients with GS are prone to developing (pulmonary) infections. Clinicians should be aware of the possible clinical effects of COVID-19 infections in this patient population.