How does skin look when there is a subcutaneous tick? - briefly
A subdermal tick appears as a firm, slightly raised papule that may be flesh‑colored or reddish, often featuring a central punctum where the mouthparts protrude. The surrounding skin can show mild erythema or a faint halo, and the tick’s body may be visible as a dark speck within the lesion.
How does skin look when there is a subcutaneous tick? - in detail
A tick that has penetrated the dermis and settled in the subcutaneous tissue creates a distinctive lesion. The entry point is usually a small, circular puncture, often less than 2 mm in diameter, without an obvious bite mark because the tick’s mouthparts remain hidden beneath the epidermis. Around this central pit, the skin may appear slightly raised or indurated, forming a firm, dome‑shaped nodule that can be palpated as a firm, immobile lump.
The overlying epidermis frequently stays intact, giving the area a smooth surface that may be pink, erythematous, or slightly hyperpigmented, depending on the host’s inflammatory response. In some cases, a thin, translucent “window” can be seen through the skin, revealing the tick’s body as a dark silhouette against the underlying tissue. This visibility is more common when the tick is engorged and its abdomen expands.
Typical accompanying signs include:
- Localized swelling extending a few millimeters beyond the puncture margin
- Mild to moderate erythema surrounding the nodule
- Possible serous or serosanguinous fluid accumulation if the tick’s feeding induces a small inflammatory exudate
- Absence of a visible external tick; the organism remains concealed within the tissue
If the host’s immune response is vigorous, the lesion may develop a central crust or ulceration as the tick dies and the tissue begins to heal. Conversely, a muted response can leave a flat, barely noticeable spot that persists for weeks until the tick detaches or is removed.
Diagnosis relies on visual inspection of the puncture site, palpation of the firm nodule, and, when necessary, dermatoscopic examination to confirm the presence of the embedded arthropod. Early identification is crucial to prevent secondary infections and potential transmission of tick‑borne pathogens.