Lichen Scrofulosorum Mimicking Lichen Planus

Abstract

Lichen scrofulosorum is the most uncommon clinicopathologic variant of the tuberculids. Usually, the eruption appears in children and adolescents with strong immune sensitivity to Mycobacterium tuberculosis and consists of tiny follicular papules, closely resembling lichen nitidus. We report a case of lichen scrofulosorum in an adult male with active cervical scrofuloderma who developed lesions of lichen scrofulosorum mimicking clinically lichen planus. Histopathologic study demonstrated granulomas around the hair follicles, although acid-fast bacilli stains, immunohistochemical stain for mycobacteria, polymerase chain reaction investigations and cultures failed to demonstrate Mycobacterium tuberculosis in the cutaneous lesions. The most striking features of the reported case were the onset of the eruption in an adult patient and the clinical appearance of the lesions, resembling lichen planus.

Update on cutaneous tuberculosis

“…4 Lichen scrofulosorum was recently described after BCG vaccination and M. avium infection. 3 , 5 , 16 , 87 , 88 …”

Lichen Scrofulosorum in a Patient with Tuberculous Cervical Lymphadenopathy: A case report

“…This is followed by a type III hypersensitivity response from the host. The continuous formation of antigen-antibody complexes may lead a type IV hypersensitivity reaction, resulting in granuloma formation [6][7][8][9].…”

“…The most frequent extracutaneous involvement of TB in association with LS is lymphadenophathy (cervical, hilar, axillary, or mediastinal) but pulmonary TB is also reported. LS can also be associated with other types of CTB such as scrofuloderma, lupus vulgaris, and erythema induratum [4,6].…”

“…Normally giant cells are absent and acid-fast bacilli are not found [3,4,6]. Tubercle bacilli are almost never seen in the biopsy specimen and they cannot be cultured [4,6,11].…”

“…Following anti-TB treatment, the lesions usually clear within 4 to 12 weeks without scarring [6,10,11,15,16].…”