Question

Case Study #2: The Case of Ruby Rhod: Severe Immunodeficiency from Loss of B and T Cells At birth, Ruby seemed to be a normal healthy baby. However, soon after birth, his mother noticed that he developed numerous abnormalities with his health, including numerous pus-filled blisters. He was admitted to the hospital, where his condition rapidly worsened. He developed enlarged lymph nodes in his neck, armpits, and groin. Medical personnel identified both Staphylococcus aureus and Candida albicans in pus from the blisters. He also showed signs and symptoms of staphylococcal and fungal infections over his body, including in his throat and on his skin. Antibacterial and antifungal treatment was initiated; however, blood tests were completed as well. The blood panel results revealed an absence of B cells and non-functioning T cells. Genetic testing was performed to identify cause of this deficiency in his B and T cells. RAG1 and RAG2 genes were sequenced and a deleterious mutation was identified in the genes, which caused the loss of B and T cells. Ruby was diagnosed with Omenn Syndrome, a form of Severe Combined Immunodeficiency (SCID). While identifying the medical cause for Ruby’s ailment, he developed a severe case of pneumonia caused by Pneumocystis jirovecii, which ultimately led to his death.

2. What are typical symptoms associated with SCID? Are Ruby’s symptoms
characteristics of someone afflicted with SCID?

Answer 1

1. Typical symptoms:

Symptoms include opportunistic and persistent infections and also abnormalities of the anatomy. Infections are always the first symptoms to SCID. The serious persistent infections are pneumonia, sepsis, meningitis, diarhoea, liver infection, yeast infection in mouth and severe skin infections.

The affected child also has abnormalities of the spleen, underdeveloped glands of thymus, absence of tonsils and lymph nodes. SCID infants have hearing loss, delayed response, movement disorders and developmental delay. The disease is X-linked and as female children have two X chromosomes, only the male child gets affected while the female child can act as carrier.

2. Yes the symptoms on Ruby relate to SCID, Omenn syndrome. Omenn syndrome is an autosomal recessive disease of the type SCID. Ruby has developed both bacterial and fungal infections that are persistent as in case of SCID. Mutation diagnosis has revealed mutations in RAG1 and RAG2 genes which leads to Omenn syndrome.