Dermatological mycobacterium infecions

skin mycobacterial diseases

• leprosy
  • only in human
• cutaneous TB
  • only in human
• non-TB mycobacterium (NTM)
  • water-borne

when to suspect

• skin symptoms WITHOUT inflammatory sings (pain, swelling, redness)
• slow progression
• specific patient background
  • occupation, living place, triggering event

cutaneous TB

• estimated 1-2% of all TB patients
• diverse range of symptoms

route of transmission

• exogenous inoculation
  • ulcer,
  • tuberculosis verrucosa cutis, warty tuberculosis
  • orificial tuberculosis - direct contact of M.t. contained in sputum from pulmonary TB
• endogenous spread from internal TB
  • abscess,
  • scrofuloderma - emerged from lymphadenitis
• hematogenous
  • nodule, abscess, patch
  • as part of miliary tuberculosis
  • immunocompromised host, children
• tuberculid - allergic reaction against M. tuberculosis
  • erythema, papule
  • in immunocompetent patient
  • skin biopsy of the eruption shows no bacteria
  • strong positivity of Mantoux test
  • Bazin erythema
    • usually localized to lower legs

treatment

• same as of systemic tuberculosis

skin NTM

all manifest in similar skin lesions, eruptions

• M. ulcerans = Buruli ulcer
• M. chelonae
• M. marinum - highest incidence
  • contact with tropical fish
• M. avium
  • long-maintained hot bath
  • hot spring
• M. peregrinum
• M. massiliense (M. abscessus subsp. massiliense)

treatment

• use more than two antibiotics to prevent from resistance
• clarithromycin, rifampicin, quinolone, minocycline..
• NO standarized regimen nor treatment duration

Buruli ulcer

diagnosis

• mandatory
  • skin manifestation
  • histopathology
  • PCR

• indigenous Buruli ulcer in Japan
  • M. ulcerans subsp. shinshuense
• total 76 cases during 1980-2020
• in all age
• 感染研：ブルーリ潰瘍