Which symptom is indicative of a lack of cellular immunity in SCID?

In severe combined immunodeficiency (SCID), the characteristic symptom indicating a lack of cellular immunity is frequent infections. SCID is a group of inherited disorders that result in a severely compromised immune system due to defects in both T and B lymphocytes. The absence of functional T cells, which are crucial for mounting an immune response against pathogens, leads to increased susceptibility to infections, particularly from opportunistic organisms that would normally be controlled by a functioning immune system. This includes a higher incidence of respiratory tract infections, gastrointestinal infections, and infections caused by viruses, bacteria, and fungi.

The other symptoms mentioned are not directly indicative of cellular immunity deficiency. Uncontrolled bleeding is more related to issues with platelet function or clotting factors rather than immune function. Hair loss and digestive issues can arise from various other conditions but do not specifically point to problems with cellular immunity like frequent infections do.