Bacterial skin infection 

• Staphylococcal Scalded Skin Syndrome 
• Toxic Shock syndrome (TSS)
• Cellulitis & Erysipelas
• Mycobacterial infection
• Leishmaniasis 

Mycobacterial infection

Mycobacterium leprae infection

• manifestations will be influenced by host immunity: 

• • high levels of immunity → paucibacillary tuberculoid leprosy (PTL)
  • low levels of immunity → multibacillary lepromatous leprosy (MLL)

• Skin presentation: 

• • Hypopigmented or erythematous patches, with altered or lost sensation, or 
  • skin thickening, nodules and infiltration

Mycobacterium tuberculosis infection

• skin is an extrapulmonary site of involvement.
• Skin manifestations depend on the route of infection, previous sensitisation and host immunity. 
• Skin presentation: (VVI)

• • lupus vulgaris: the red–brown scarring inflammatory plaques due to direct skin inoculation.
  • scrofuloderma: skin changes overlying lymph nodes or joints infected with tuberculosis.
  • erythema induratum (Bazin’s disease): the reactive nodular and ulcerated changes seen in patients with high levels of immune response.

• Investigation: 

• • Diascopy:  ‘apple jelly’ appearance → indicates granulomatous nature of skin involvement. 
  • Full thickness skin biopsy with histopathology: Granulomas 
  • Culture, GeneXpert, PCR  
  • Thoroughly investigations for signs of tuberculosis at pulmonary or other extrapulmonary sites. 
  • Investigation for latent tuberculosis