Table 1.
Similarities and differences in the clinical appearance of stinging and biting arthropods, ectoparasites or other dermatological diseases and bed bug bites
| Diagnosis | Similarities | Differences | |
|---|---|---|---|
| Stinging and biting arthropods: | |||
| Honeybee, wasp sting [49] | Painful and/or pruritic wheal, flare with a central punctum | Single lesion. Immediate reaction, systemic reactions are not rare. Patients are aware of the bite | |
| Spider bite [50] | Painful and/or pruritic wheal, flare or papule with a central punctum | Single or few lesions with 1–2 new lesions per day. Diameter is between 1–40 cm | |
| Ectoparasites: | |||
| Tick [51] | Erythematous papule with a central punctum | Single lesion without itch. Report about being in the nature. Ticks may remain attached to the skin for a longer time | |
| Body lice [52] | Multiple erythematous papules, excoriation | Symptoms under clothing. Diameter of the lesions is 3–5 mm. Lice and their eggs are visible | |
| Flea [52] | Multiple bites on the extremities and trunk. Can occur in a linear pattern | Presence of animals. Diameter of the lesion is maximum 5–10 mm | |
| Scabies [53] | Pruritic erythematous papules in predilection sites – interdigital, sacral, genital area, wrists | Diameter of the lesion is 3–5 mm. Symptoms appear after 3–6 weeks. Itch during night. Different predilection areas | |
| Other diseases: | |||
| Bullous erysipelas [54] | Bullae with serous or haemorrhagic fluid. Unilateral distribution is possible. Limbs affected | Only one limb, always unilateral. Fever is present. Extensive erythema, flame-pattern. Confluent bullae | |
| Delusions of parasitosis (Ekbom syndrome) [55] | Erythematous papules. Severe pruritus, excoriations | Centre of the back and face is spared. Psychiatric anamnesis. Feel of constant biting, crawling. Patients tend to “remove the pathogens” and are convinced about having an infestation | |
| Herpes zoster [56] | Painful vesicles with erythematous base, rarely linear arrangement | Unilateral grouped vesicles following a dermatome, except for the disseminated form | |
| Reactive perforating collagenosis [57] | Erythematous papule with central erosion, usually pruritic. Appears on limbs | Acquired form with diabetes or chronic renal failure. Lesions may be a response to superficial trauma, scratching | |