Tuberculoid granulomas in cutaneous sarcoidosis: a study of 49 cases

Granulomas in Dermatopathology: Principal Diagnoses - Part 2

Part 2 of this series on granulomatous diseases focuses on skin biopsy findings. Whereas the first part treated noninfectious conditions (metabolic disorders and tumors, among other conditions), this part mainly deals with various types of infectious disease along with other conditions seen fairly often by clinical dermatologists.

Looking beyond the cosmetic tattoo lesion near the eyebrow: Screening the lungs

Cosmetic tattooing has become a risk factor for several adverse reactions related to inks, procedures, and associated clinical conditions. Development of a sarcoid reaction to the inserted tattoo pigment in the skin is not common. We report a 45 year-old patient with history of dyspnea and mild cough since two years who had subsequently developed reddish, scaly lesions in her 15-year old tattoo done near her right eyebrow. Skin biopsy of the tattoo lesion revealed cutaneous sarcoidosis which led to further investigations and a diagnosis of pulmonary sarcoidosis. The present case highlights the fact that cutaneous sarcoidosis can develop in a long-standing tattoo. Also such a patient should be screened for systemic sarcoidosis disease.

Histologic features of granulomatous skin diseases. Part 1: Non-infectious granulomatous disorders

Granulomatous disorders affecting the skin belong to a heterogeneous group of diseases. With the exception of granulomas induced by infectious agents or foreign bodies, the etiopathogenesis of granulomatous disorders is still poorly understood. The knowledge of histopathologic changes is of great importance for understanding clinical presentation and disease course.

Sarcoidosis and molecular mimicry--important etiopathogenetic aspects: current state and future directions

Sarcoidosis is a disease of uncertainty in terms of its cause, presentation, and clinical course. The disease has a worldwide distribution and affects all ages, races, and both sex. Sarcoidosis of the skin may have an extremely heterogeneous clinical presentation, so that the definitions of 'great imitator' and 'clinical chameleon' have long been used. The factors that influence clinical picture and severity of the disease are probably linked to the etiopathogenesis of sarcoidosis, which continues to be shrouded in mystery. The current state of the art on the pathogenesis of sarcoidosis is that it is an immunological response in a genetically susceptible individual to an as-yet undefined antigenic stimulus. How exposure occurs in genetically predisposed patients is not completely clear, but the most likely explanation is that these agents or antigens are either inhaled into the lungs or enter through contact with the skin, as these are the common target organs that are constantly in contact with the environment. An autoimmune etiology of sarcoidosis could possibly occur through a process of molecular mimicry of infectious or other environmental antigens to host antigens. This could lead to a cross-mediated immune response and induction of autoimmune disease. This molecular mimicry may probably be responsible for the heterogeneous clinical presentations of the disease. Several investigations and studies have provided valuable evidence on the etiopathogenesis of sarcoidosis, which may lead to the future development of targeted and innovative treatment strategies. Nevertheless, we are still a long way from unravelling the underlying cause of this mysterious disease.