Changing the way we diagnose tuberculids with interferon gamma release assays

Abstract

Diagnosing tuberculids traditionally requires clinicopathological correlation together with positive tuberculin skin tests (TST) or demonstration of Mycobacterium tuberculosis (MTB) DNA by polymerase chain reaction (PCR). Interferon gamma release assays (IGRA) are new laboratory tests approved for the diagnosis of MTB infection. We describe three patients with tuberculids who had no other clinical feature of tuberculosis (TB) infection and negative PCR of skin biopsies. Their diagnoses were aided by positive IGRA.

Tuberculids: cutaneous indicator diseases of Mycobacterium tuberculosis infection in young patients

“…Diagnosis is made by histo‐pathology combined with the clinical image and response to therapy. PCR, a tuberculin skin test or IGRA test can be helpful …”

“…PCR, a tuberculin skin test or IGRA test can be helpful. 7 There are different clinical manifestations of tuberculids: lichen scrophulosorum, papulonecrotic tuberculids and erythema induratum of Bazin. In some cases multiple forms of cutaneous tuberculids can co-exist.…”

An unusual perineal plaque

“…10 Polymerase chain reaction can also be used. However, the enzyme-linked immunospot assay for interferon-gamma (TB Elispot) has been shown to be very helpful in the diagnosis of cutaneous tuberculosis 11 with a sensitivity of 91.6%. 12 A negative test therefore makes the diagnosis of tuberculosis unlikely.…”

Off-Label Uses of Topical Vitamin D in Dermatology: A Systematic Review

“…Other cutaneous neoplasms and dyskeratotic disorders reported to respond to calcipotriol or maxacalcitol include Bowen disease, 113 systematized epidermal nevus (combination calcipotriol/betamethasone diproprionate), 114 nevus comedonicus (combination of tazarotene and calcipotriol), 115,116 stucco keratosis, 117 and eruptive vellus hair cysts. 118 These all represent isolated case reports, and adequate assessment of therapeutic efficacy cannot be established in an evidence-based fashion.…”