Kimura disease with Nocardiosis in a child with a novel mutation in IL12RB1gene

Area of Science:

• Immunology
• Genetics
• Infectious Diseases

Background:

• Kimura disease is a rare chronic inflammatory condition.
• Mendelian Susceptibility to Mycobacterial disease (MSMD) involves genetic defects in cytokine signaling pathways.
• Primary immune deficiency disorders (PIDs) predispose individuals to severe infections.

Observation:

• A 12-year-old boy with Kimura disease presented with symptoms of acute pyelonephritis.
• A family history of MSMD was noted.
• Investigations identified a left renal abscess from which Nocardia otitidiscaviarum was cultured.

Findings:

• Targeted gene sequencing identified a novel mutation in the IL12RB1 gene.
• The findings suggest an underlying primary immune deficiency disorder.
• The patient's condition was attributed to a genetic defect in the IL-12/IL-23 signaling pathway.

Implications:

• This case highlights the importance of considering PIDs in patients with recurrent or unusual infections, even with pre-existing conditions like Kimura disease.
• Identification of a novel IL12RB1 mutation expands the known genetic spectrum of PIDs.
• Early diagnosis and targeted antibiotic therapy led to complete recovery, underscoring the treatability of certain PIDs.