Post-vaccination subcutaneous aluminum granuloma

Area of Science:

• Immunology
• Pathology
• Public Health

Background:

• Vaccination is a vital public health measure, often utilizing aluminum-containing adjuvants to enhance immune responses.
• Adjuvants can cause local side effects, including persistent itch, but asymptomatic presentations like subcutaneous nodules can pose diagnostic challenges.

Purpose of the Study:

• To present a case of asymptomatic subcutaneous nodules in a child, diagnosed as post-vaccination aluminum granuloma.
• To highlight the diagnostic features and management approach for this benign condition.

Main Methods:

• Case presentation of a 1-year-old girl with asymptomatic subcutaneous nodules.
• Diagnostic workup included Magnetic Resonance Imaging (MRI) and histological examination of excised nodule.
• Histology assessed for granulomatous reaction, lymphoid structures, macrophages, and confirmed aluminum presence using PAS and aluminon staining.

Main Results:

• MRI revealed subcutaneous lesions on both upper arms.
• Histological examination showed a granulomatous reaction with lymphoid follicle-like structures and macrophages containing aluminum deposits.
• Aluminum was confirmed via positive aluminon staining.

Conclusions:

• The findings confirmed a diagnosis of post-vaccination aluminum granuloma.
• Given the benign nature of aluminum granuloma and the importance of vaccination, continuation of the routine vaccination schedule was recommended.