Background: The coronavirus disease 2019 (COVID-19) pandemic has affected millions of people around the world. This zoonotic-enveloped virus is primarily transmitted through inhalation. Infected people are commonly asymptomatic or manifest mild symptoms, including fever, cough, diarrhea, and fatigue. However, it may lead to severe patterns associated with multiple organ failure in individuals with an impaired immune system.
Objective: Here we report a 7-year-old girl with hyper-immunoglobulin M (IgM) (HIgM) phenotype, admitted to the hospital emergency department with fever, cough, and pneumonia symptoms because of the COVID-19 infection. Coronavirus infection was confirmed by a positive real-time polymerase chain reaction test. Surprisingly, serum levels of both IgG and IgA of the patient were transiently normalized during the COVID-19 infection when tested prior to the monthly injection of intravenous immunoglobulin. After she recovered from the COVID infection, her immunoglobulin levels returned to the primary stage and she demonstrated HIgM phenotype.
Conclusion: Since this transient increase in the levels of immunoglobulins was solely observed during the COVID-19 infection, and no other infectious episodes were diagnosed in the patient, clarifying the exact cause would help to understand in a better manner the implications and specification of humoral immunity in patients with primary antibody deficiencies.
Keywords: COVID-19; IgG; humoral immunity; hyper-IgM syndrome; primary immunodeficiency.