Behçet disease is a relapsing multisystem vasculitis of small and large vessels that presents with recurrent oral aphthae, genital ulcers, ocular inflammation, and a variety of cutaneous lesions. International criteria require at least two additional signs, such as skin pustules, erythema nodosum, or a positive pathergy reaction. Because lesions often heal within days or weeks, objective documentation between flares is difficult.
What causes Behçet's disease?
The cause of Behçet disease remains unknown. Current evidence indicates that it results from the interaction of a genetically primed immune system with one or more environmental triggers. The strongest genetic association lies within the HLA class I region: carriage of HLA-B*51 increases disease susceptibility three- to six-fold, while non-HLA polymorphisms affecting interleukin-10, interleukin-23 receptor and endoplasmic reticulum aminopeptidase-1 further modulate risk. These variants favour a Th1-biased and Th17-biased immune response that, after exposure to an exogenous factor, precipitates widespread vasculitis. Environmental candidates include microbial antigens: Streptococcus sanguinis DNA and heat-shock proteins have been recovered from mucosal lesions, and hypersensitivity to this commensal can reproduce disease features in animal models. Herpes simplex virus DNA and RNA have also been detected in saliva and peripheral blood mononuclear cells, although no single pathogen has been established as the inciting agent. Additional, non-infectious influences—such as vitamin D deficiency or sex hormones—may amplify neutrophil activation and endothelial damage, ultimately leading to the systemic vascular inflammation characteristic of Behçet disease.
Is Behçet's disease serious?
Behçet's disease is uncommon. Population-based studies along the historic Silk Road report the highest prevalence, ranging from 80 to 370 per 100,000 in Turkey and 13.5–35 per 100,000 in Japan, Korea and Iran, whereas in North America and Northern Europe the figure falls to 0.12–7.5 per 100,000. Despite its rarity, the disorder can cause significant harm. Most patients experience recurrent oral and genital ulcers that impair eating, speaking and personal relationships. Ocular involvement, present in up to one half of cases, may lead to progressive visual loss; vascular lesions such as arterial aneurysms or venous thrombosis can be life-threatening; and central nervous system or gastrointestinal disease can result in permanent disability. No permanent cure exists. Randomised trials show that colchicine, corticosteroids, conventional immunosuppressants and tumour-necrosis-factor inhibitors reduce flare frequency and severity, yet complete sustained remission is uncommon and relapses remain the rule.
Why consider dermatoscopy?
Dermatoscopy—also called dermoscopy or mucoscopy when applied to mucosae—offers non-invasive, magnified visualisation of subsurface vascular and keratin patterns. The technique is already validated for melanoma and inflammatory dermatoses, and pilot studies have begun to apply it to Behçet disease with two distinct aims: first, to capture reproducible images of transient oral, genital and skin lesions; second, to refine the reading of the pathergy test, a diagnostic clue in which a sterile needle prick induces an exaggerated papulo-pustular reaction after 24–48 h.
Does dermatoscopy improve the pathergy test?
The classical pathergy test is read clinically at 48h; any papule ≥ 2 mm is deemed positive. Inter-observer agreement is modest because early or small reactions are easily missed. Two independent groups used a handheld dermatoscope to re-examine the prick sites: positive reactions revealed a structureless pink-to-purple background with central punctate scales or sterile pustules, whereas negative sites showed only the needle mark with minimal erythema. Magnified images allowed measurement of lesions as small as 1 mm and increased inter-rater reliability. Biopsy confirmed a perivascular neutrophilic infiltrate beneath dermatoscopic lesions, supporting the visual criteria.
What are the advantages of dermatoscopy?
The IBOOLO dermatoscope series includes the pocket dermatoscope series and the handheld dermatoscope series. The main difference between these two series is that the pocket dermatoscope can only be used to observe skin lesions by connecting to a smartphone, while the handheld dermatoscope can be used both by connecting to a smartphone and by holding the dermatoscope directly to observe skin lesions with the naked eye.
For the observation of Behçet's disease, any IBOOLO dermatoscope can be connected to a smartphone to record the findings. By analyzing the morphological changes of Behçet's disease over different time periods, doctors can better assess the patient's recovery status and thereby provide more effective treatment.
What are the treatment options for Behçet's disease?
Treatment of Behçet disease is individualised according to organ involvement and disease severity. For isolated oral or genital ulcers, topical corticosteroid pastes or intralesional triamcinolone suffice. Colchicine 1–1.5 mg daily is recommended for recurrent mucocutaneous disease and has been shown in randomised trials to reduce aphthous ulcer frequency by about one half. When eye, central nervous system, vascular or gastrointestinal disease is present, systemic immunosuppression is mandatory.