[BCGitis/BCGosis in children: Diagnosis, classification and exploration]

Area of Science:

• Immunology
• Vaccinology
• Infectious Diseases

Background:

• The Bacille Calmette-Guérin (BCG) vaccine is a widely used live vaccine protecting children against severe tuberculosis.
• While generally safe, BCG vaccination can lead to rare complications, including local BCGitis and disseminated BCGosis.
• The incidence and presentation of BCG complications vary geographically.

Purpose of the Study:

• To review the epidemiology, etiology, diagnosis, and management of BCG vaccine complications.
• To highlight the importance of identifying underlying immunodeficiencies in patients with BCG disease.
• To discuss recent advances in molecular diagnostics for differentiating BCG infections.

Main Methods:

• Review of existing literature on BCG complications.
• Analysis of diagnostic approaches including clinical examination and laboratory findings.
• Discussion of therapeutic strategies and management guidelines.

Main Results:

• BCG complications range from localized inflammation to life-threatening disseminated disease.
• Etiologies include vaccine-related factors (technical errors, strain) and patient-related factors (primary or acquired immunodeficiencies).
• Molecular biology aids in distinguishing BCG disease from other mycobacterial infections.

Conclusions:

• Prompt diagnosis and investigation of underlying immune defects are essential for managing BCG complications.
• Prognosis is influenced by immune status and the timeliness of appropriate management.
• Standardized diagnostic and therapeutic protocols for BCG disease are evolving.