Lichen scrofulosorum

A 12-month-old boy with pulmonary tuberculosis developed a papular lichenoi d eruption which showed epithelioid granulomas on histology, consistent wit h lichen scrofulosorum. stains and cultures for mycobacteria in the skin we re negative, and a polymerase chain reaction (PCR) analysis failed to detec t the DNA of Mycobacterium tuberculosis in a skin biopsy specimen, thus mak ing lichen scrofulosorum one of the remaining manifestations of M. tubercul osis infection in which evidence of the bacillus has not been found to date . Lichen scrofulosorum is now considered a rare form of tuberculid but shou ld not be neglected.