Capillaritis—also known as pigmented purpuric dermatosis—presents as rust-coloured pepper-like speckles, most often scattered across the shins. While the eruption is asymptomatic or only mildly pruritic, its chronic, disfiguring appearance can provoke substantial cosmetic distress. Because the lesions mimic vasculitis, drug reactions, or even early mycosis fungoides, accurate bedside recognition is critical. Over the last decade, dermatoscopy has moved from a research curiosity to a front-line tool that can instantly unveil the subtle vascular and pigment patterns characteristic of capillaritis.
What Is Capillaritis?
Capillaritis is a group of chronic, non-palpable purpuric dermatoses that share the histologic hallmark of red-cell extravasation around superficial dermal capillaries with subsequent hemosiderin deposition. The most common subtype is Schamberg disease, followed by Majocchi purpura annularis telangiectodes, Gougerot–Blum pigmented purpuric lichenoid dermatosis, and the more localized lichen aureus. Prevalence is unknown but likely under-reported; many series show a male predominance and peak incidence between 30–60 years.
Capillary fragility, venous hypertension, gravitational stasis, and aberrant T-cell–mediated inflammation have all been implicated. External triggers include prolonged standing, exercise, contact allergens, certain drugs (e.g., acetaminophen, calcium channel blockers), and food additives.
Patients present with asymptomatic, non-blanching, red-brown to ochre macules and patches, most prominently on the lower extremities. Lesions may remain fixed for months or wax and wane in crops.
How Does Dermatoscopy Work?
Basic principles
Dermoscopy (epiluminescence microscopy) employs 10X magnification with either polarised or non-polarised light to reduce surface reflection and visualise structures up to the superficial dermis. Modern devices such as the IBOOLO DE-4100 Pro offer four illumination modes—non-polarised white, polarised white, 365 nm UV, and amber light—to optimise contrast of both vascular and pigmentary structures.
Practical technique
1. Clean the skin
2. Rest the lens gently on the lesion; adjust focus and brightness to avoid blooming artifacts.
3. Capture both overview and close-up polarised images
Can Dermatoscope Reveal Specific Signs of Capillaritis?
The dermoscopic signature of capillaritis is a triad of:
• Red to copper “cayenne pepper” petechiae—round or oval dots measuring 0.1–0.3 mm with sharp borders.
• Patchy ochre or brown background pigmentation corresponding to hemosiderin incontinence.
• Absence of Wickham striae, scutula, or other epidermal alterations, helping to rule out lichen planus and psoriasis.
This month IBOOLO launched a new pocket dermatoscope—the DE-500, which utilizes a four-element, three-group lens design for virtually distortion-free 10X magnification. Compared with its predecessors, the DE-300 and DE-400, the DE-500 offers a more versatile set of lighting modes and adds three-step brightness adjustment. It contains polarized, unpolarized and UV light and is suited for observing capillaritis. On the back, a circular magnetic ring lets the device snap instantly onto the universal phone clip included in the kit—no more screwing the dermatoscope’s threaded base into the clip as required on earlier models.
Does Dermatoscopy Aid in Differential Diagnosis?
Capillaritis vs. vasculitis
Leukocytoclastic vasculitis displays larger, more confluent purpuric plaques with palpable borders and often ulceration; dermoscopy shows central necrosis, purpura, and peripheral reticular vessels but lacks the fine pepper dots.
Capillaritis vs. mycosis fungoides-like purpura
Early patch-stage mycosis fungoides may present as purpuric lesions, yet dermoscopy reveals sparse, short linear vessels and fine white scales rather than densely packed petechiae.
Capillaritis vs. drug eruption
Fixed drug eruptions show dusky patches with peripheral hyperpigmentation; dermoscopy demonstrates focal grey–brown structureless areas and occasional targetoid vessels, easily distinguished from the uniform pepper pattern.
Is Dermatoscopy Useful for Treatment Decisions?
Assessing severity
Dermoscopy can quantify dot density and ochre background intensity, providing an objective baseline for treatment response. Serial imaging every 4–6 weeks allows early detection of fading petechiae or re-pigmentation.
Guiding therapy
• If petechiae are sparse and ochre background mild, reassurance plus compression stockings may suffice.
• Denser, more extensive lesions warrant topical steroids or calcineurin inhibitors; dermoscopic improvement (decreased dot density) often precedes clinical clearing by 2–3 weeks.
• Refractory cases scheduled for narrow-band UVB or laser therapy can use dermoscopic scores as inclusion criteria and monitoring endpoints.
Monitoring recurrence
Patients often stop treatment once lesions fade; however, dormant hemosiderin may re-pigment with minor trauma. Quarterly dermoscopic snapshots detect subclinical flare-ups and prompt early intervention.
Are Prevention and Daily Care Effective?
Skin-care routine
Gentle cleansers, fragrance-free moisturisers containing ceramides or 5 % urea, and broad-spectrum SPF 50 sunscreen reduce inflammation and post-inflammatory hyperpigmentation.
Lifestyle measures
• Elevate legs above heart level for 15 minutes after prolonged standing.
• Switch to low-impact exercise (swimming, cycling) to minimise micro-vascular trauma.
• Review medications and diet with a physician; eliminate unnecessary NSAIDs, acetaminophen, or artificial colourants.
Long-term outlook
Although capillaritis may spontaneously remit after months or persist for years, consistent dermoscopic follow-up and simple preventive steps significantly decrease both flare frequency and cosmetic impact.