In fact, patients with agammaglobulinemia (caused by a lack of B lymphocytes), show mild symptoms, short duration, and no need of treatment by IL-6 inhibitors, while patients exhibiting variable immune deficiencies with dysfunctional B lymphocytes, (also showing significant low levels of immunoglobulins in the serum), show severe outcomes and require mechanical ventilation, antiretroviral agents and IL-6-blocking agents (215). Here, IL6 is linked to agammaglobulinemia.