Lupus Vulgaris in Darker Skin: Dermoscopic and Histopathologic Incongruity

Lupus vulgaris: a narrative review

Lupus vulgaris (LV) is a type of paucibacillary cutaneous tuberculosis that can occur due to inoculation, lymphatic, or hematogenous route. It occurs in a previously sensitized individual with high immunity to tuberculosis. LV can have different morphology of presentation, which can lead to difficulty in diagnosis. The Tuberculin test is strongly positive. Histopathology will show epithelioid granulomas in the superficial dermis and acid-fast bacilli rarely demonstrable within the granulomas. Dermoscopy will show focused linear vessels on a yellow to orange background. Culture is the gold standard for diagnosis, but its positivity rate is low. Mycobacterium tuberculosis bacilli can be detected using polymerase chain reaction from the lesions. Histopathology, tuberculin test, dermoscopy, molecular test, and culture would help diagnose LV. This review discusses the introduction, pathogenesis, clinical features, differential diagnosis, investigations, complications, and treatment of lupus vulgaris in detail. This review can help the dermatologist understand the condition better with appropriate diagnosis and therapy.

A Systematic Review of Diagnoses with Rosettes Under Dermoscopy

INTRODUCTION

Rosettes are a cluster of shiny white dots in the shape of a four-leaf clover seen under polarized dermoscopic light. Historically, rosettes were primarily reported in actinic keratoses and squamous cell carcinoma. However, rosettes have also been reported in other conditions.

OBJECTIVES

The objective of this systematic review to elucidate the breadth of diagnoses exhibiting this unique dermoscopic phenomenon.

METHODS

A review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Literature searches were performed in MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and Web of Science, as well as a manual search of the reference lists of screened articles.

RESULTS

A total of 73 articles met the inclusion criteria. Out of these, 47 distinct diagnoses with rosette were identified. Among neoplastic conditions, keratinizing neoplasms had the highest number of articles reported (N = 19). Discoid lupus was the most commonly reported diagnosis within the inflammatory category (N = 6). Molluscum contagiosum was the predominant diagnosis among infectious entities (N = 3), while acroangiodermatitis was the sole diagnosis reported in the vascular category (N = 1).

CONCLUSIONS

These findings confirm rosettes are not specific to keratinocytic growths and are observed in a wide range of conditions. Knowledge of the breadth of conditions with rosettes may aid clinicians when developing a differential diagnosis of a growth or an eruption with rosettes under dermoscopy.

Cutaneous tuberculosis. Part I: Pathogenesis, classification, and clinical features

Tuberculosis is an ancient disease that continues to affect an estimated 10 million people per year and is responsible for 1.4 million deaths per year. Additionally, the HIV epidemic and multidrug resistance present challenges to disease control. Cutaneous tuberculosis is an uncommon, often indolent, manifestation of mycobacterial infection that has a varied presentation. Its diagnosis is challenging, as lesions mimic other, more common conditions and microbiological confirmation is often not possible. Cutaneous tuberculosis can be broadly categorized into multibacillary and paucibacillary forms. Approximately one-third of skin tuberculosis is associated with systemic involvement. By recognizing cutaneous tuberculosis early, dermatologists can play an important role in disease control. The first article in this 2-part continuing medical education series describes the latest epidemiology, microbiology, and pathogenesis of tuberculosis. Furthermore, we review the classification, clinical manifestations, common clinical differentials, and systemic involvement that occur in cutaneous tuberculosis.

Dermoscopy of Infectious Dermatoses (Infectiouscopy) in Skin of Color - A Systematic Review by the International Dermoscopy Society "Imaging in Skin of Color" Task Force

Dermoscopy has been showed to facilitate the non-invasive recognition of several infectious disorders (infectiouscopy) thanks to the detection of peculiar clues. Although most of the knowledge on this topic comes from studies involving light-skinned patients, there is growing evidence about its use also in dark phototypes. This systematic literature review summarizes published data on dermoscopy of parasitic, bacterial, viral and fungal dermatoses (dermoscopic findings, used setting, pathological correlation, and level of evidence of studies) and provides a homogeneous terminology of reported dermoscopic features according to a standardized methodology. A total of 66 papers addressing 41 different dermatoses (14 bacterial, 5 viral, 11 fungal infections, and 11 parasitoses/bites and stings) and involving a total of 1096 instances were included in the analysis. The majority of them displayed a level of evidence of V (44 single case reports and 21 case series), with only 1 study showing a level of evidence of IV (case-control analysis). Moreover, our analysis also highlighted a high variability in the terminology used in the retrieved studies. Thus, although promising, further studies designed according to a systematic and standardized approach are needed for better characterization of dermoscopy of infectious skin infections.

Multifocal Lupus Vulgaris: A Rare Presentation

Lupus vulgaris (LV) is a common type of cutaneous tuberculosis and commonly presents as a single erythematous plaque either on the face or buttocks with scarring and an active spreading edge. Multiple lesions of LV are sparingly reported in the literature. We hereby report a case of LV in a male presenting with multiple lesions over the buttock, thigh, and trunk. The diagnosis was done on the basis of clinical findings, histopathology, positive tuberculin test, and response to a standard anti-tubercular regimen.

Dermoscopy of the Diverse Spectrum of Cutaneous Tuberculosis in the Skin of Color

INTRODUCTION

Cutaneous tuberculosis is an uncommon form of tuberculosis, accounting for 1%-2% of all forms of extra-pulmonary tuberculosis. Knowledge of the dermoscopic characteristics of different clinical types of cutaneous tuberculosis can help timely diagnosis resulting in better outcomes.

OBJECTIVES

To characterize the Dermoscopy findings in different clinical types of cutaneous tuberculosis in dark skin phototypes.

METHODS

All clinically suspected and biopsy confirmed cases of cutaneous tuberculosis seen from July 2019 through December 2021 were retrospectively recruited. Information including age, gender, disease duration, site and morphology of lesions, and presence of concomitant tuberculosis elsewhere was noted. Two investigators retrospectively reviewed the dermoscopic characteristics of these cases.

RESULTS

Twenty-two patients comprised of 12 women and 10 men met the inclusion criteria. Lupus vulgaris was the commonest presentation of cutaneous tuberculosis seen in 13 patients. Five had scrofuloderma, 2 had tuberculosis verrucosa cutis and 1 patient each had lichen scrofulosorum and papulo-necrotic tuberculid. Yellow-orange structureless areas (100%), linear/dot vessels (100%), white scales (92.3%), and white structureless areas (84.6%) were the predominant dermoscopy findings in lupus vulgaris. In scrofuloderma, linear vessels and white structureless areas were visible in all cases. Dirty white scales with a papillated surface were characteristically seen in tuberculosis verrucosa cutis, with 1 of the 2 patients each showing vessels and yellow-orange structureless areas. White globules with surrounding erythema were seen in lichen scrofulosorum and yellow-orange structureless areas with keratin plugs in papulo-necrotic tuberculid.

CONCLUSIONS

A thorough understanding of the characteristic dermoscopy of cutaneous tuberculosis can help suspect the diagnosis early resulting in better management opportunity.