Table II.

Summary of the clinical presentation, histology and tuberculin skin test for the subtypes of cutaneous tuberculosis

Form of CTB	Clinical presentation	Histology and TST
Lupus vulgaris	Nontender plaques or nodules with ulceration Progress to well-defined, scaly plaques Located on face or neck (hematogenous spread) or extremities (exogenous reinoculation) Cervical and supraclavicular lymphadenopathy	Paucibacillary Granulomas, giant cells, and caseous necrosis Positive TST
Tuberculous chancre	Erythematous papules Progress to firm non-tender ulcers Upper and lower limbs +/− Lymphadenopathy	Multibacillary Granulomatous inflammation with caseous necrosis TST is positive.
Tuberculosis verrucose cutis	Small papules surrounded by inflammation that develops into a wart-like lesion	Paucibacillary Hyperkeratosis and tuberculoid granulomas in the dermis Positive TST
Periorificial lesions	Painful ulcers in the oral or perineal regions	Multibacillary Granulomatous inflammation with caseous necrosis
Scrofuloderma	Firm nodules which ulcerate, forming purulent sinus tracts Cervical and postauricular lymphadenopathy	Multibacillary Granulomatous inflammation with caseous necrosis
Tuberculosis miliaris cutis disseminate	Widespread papules and crusted vesicles Immunocompromised patient	Multibacillary Nonspecific inflammation with necrotizing vasculitis
Metastatic abscesses	Multiple nodules that may ulcerate or form draining sinus tracts +/− Cervical lymphadenopathy	Multibacillary Granulomatous inflammation with caseous necrosis
Tuberculid forms Lichen Scrofulosorum Papulonecrotic Tuberculid	Lichenoid papules which may form plaques and scale Bilateral and symmetrical distribution Necrotic papules	Paucibacillary; TST positive Granulomatous inflammation without caseation with a parakeratotic epidermis Necrosis and granulomatous inflammation