Tuberculids: A narrative review

Abstract

Tuberculids are a group of dermatoses with tuberculoid histology and the absence of tubercle bacilli. They are considered to be hypersensitivity reactions to circulating Mycobacterium tuberculosis (M. tb) or its antigens in individuals with good immunity. The objective of the review is to provide a detailed literature review of all available articles on tuberculids in the past 10 years and provide an update on epidemiology, etiopathogenetic mechanisms, clinical manifestations, and treatment. A search was performed on PubMed using the keywords lichen scrofulosorum, papulonecrotic tuberculid, erythema induratum, and erythema nodosum tuberculosis for all articles, with no restrictions on age, gender, or nationalities. An update on tuberculids, including some new concepts in pathogenesis, atypical presentations, new investigative modalities, and treatments are reviewed.

Pulmonary Tuberculosis With Left Pleural Effusion and Lichen Scrofulosorum: A First-of-Its-Type Report

“…Diagnosis is aided by strong Mantoux positives, distinctive histological characteristics, and the lack of M. tuberculosis in culture. Treatment is conservative with antituberculous drugs as used for systemic tuberculosis [5,6]. All these were noted in the present case.…”

“…A study of 221 patients revealed that 70.5% of them were children. The trunk was the primary area affected (98.6%), followed by the lower limb (25.33%), upper limb (15.83%), face (5%), and external genitalia (3.6%) [5,9]. In the present case, the trunk was also mainly involved.…”

“…Lichen scrofulosorum, also known as "tuberculosis cutis lichenoides," is classified as a true tuberculid and is a rare clinicopathologic manifestation of tuberculids [5,7]. It was first detailed by Hebra in 1860 [6].…”

“…Around the world, the prevalence of tuberculids among cases of cutaneous tuberculosis ranges from 4% to 44.2%. In many regions of the world, erythema induratum of Bazin is thought to be the most prevalent tuberculid, yet Indian studies indicate that lichen scrofulosorum is the most common [5].…”

Cutaneous tuberculosis: An infrequent manifestation of a common pathogen in South Africa

“…For example, tuberculids, a paucibacillary form of cutaneous TB, develop as immunological reactions to antigenic components of mycobacteria and usually occur in patients with a good cellular immunity. 13 Conversely, in our patient who was severely immunocompromised, the lesions were multibacillary, as evidenced by the positive stain for acid-fast bacilli on the pus aspirated.…”