[From scrophula to mycobacterial lymphadenitis]

Area of Science:

• Medical Microbiology
• Infectious Diseases
• Immunology

Background:

• Historically, scrophula (cervical lymph node swelling) and tuberculosis were attributed to inherited predispositions.
• Robert Koch identified Mycobacterium tuberculosis as the causative agent of human tuberculosis and scrophula in 1882.

Observation:

• Mycobacterium bovis was identified as a cause of human cervical lymphadenitis, particularly in children consuming unpasteurized milk from infected cattle.
• A distinct form of cervico-facial lymphadenitis linked to non-tuberculous mycobacteria was described in 1956, primarily affecting young children in non-endemic regions.
• Tuberculous cervical lymphadenitis remains prevalent in young adults from tuberculosis-endemic areas and in individuals with HIV.

Findings:

• The understanding of scrophula shifted from inherited diathesis to infectious etiology.
• Control of bovine tuberculosis and milk pasteurization significantly reduced Mycobacterium bovis-related lymphadenitis.
• Current research investigates genetic mutations influencing susceptibility to mycobacterial infections.

Implications:

• Infectious agents are the primary drivers of scrophula and tuberculous lymphadenitis, not inherited constitution.
• Public health interventions like cattle disease control and milk pasteurization are crucial for preventing mycobacterial infections.
• Understanding genetic susceptibility may lead to novel strategies for managing and preventing mycobacterial diseases.