Dermatology - Scabies

Dermatology - Scabies 
​The mite Sarcoptes scabiei var. hominis causes scabies, an epidermal infestation that is spread by skin-to-skin contact and bites. On clothes or bedding, mites can survive for more than two days.

Patients frequently report experiencing such symptoms in close relatives or romantic partners.
Intense, pervasive pruritus typically spares the head and neck and disrupts sleep. Atopy-prone individuals may develop eczematous dermatitis, but other individuals may have pruritus for several months without any visible symptoms. There is a chance of secondary infection, which manifests as tenderness.
Damage
Hypersensitivity, lesions brought on by persistent rubbing and scratching, and secondary infection are among the lesions that appear at the infestation site. Skin-colored, linear or serpiginous ridges, 0.5–1 cm long, with a tiny vesicle or papule at the end of the tunnel, are present at the infection site. Burrows typically occur in regions with few or no hair follicles, typically in the thin and delicate stratum corneum (the interdigital webs of hands, wrists, penis shafts, elbows, feet, buttocks, and axillae). Burrows are 5 mm on average, although they can reach up to 10 cm in length.
Nodules that range in size from 5 to 20 mm and are smooth, red, pink, tan, or brown may appear.
Widespread, tiny, urticarial, edematous papules, mainly on the anterior trunk, thighs, buttocks, and forearms, are indicative of hypersensitivity reactions. There may be hypo- and hyperpigmentation following an inflammation.

Clinical diagnosis and, if feasible, microscopy (detection of mites, eggs, or mite excrement) are used to confirm the diagnosis. Atopic dermatitis, allergic contact dermatitis, metabolic pruritus, urticaria pigmentosa, papular urticaria, prurigo nodularis, and pseudolymphoma are among the conditions on the differential.

Treat infected people concurrently with those in close physical contact, regardless of the presence of symptoms. Apply lindane (g-benzenehexachloride) 1% lotion or cream to every part of the body starting at the neck and washing it off completely after 8 hours, or permethrin 5% cream from head to toe. Lindane shouldn't be used by patients with significant dermatitis, women who are pregnant or nursing, children under the age of two, or after taking a bath or shower. There is lindane resistance in mites. In many nations, lindane is a crucial substitute due to its low cost. As an alternative, apply 10% crotamiton, 2%–10% sulfur in petrolatum, 10% and 25% benzyl benzoate, benzyl benzoate with sulfiram, 0.5% malathion, 25% sulfram, and 200 μg/kg of ivermectin. Intralesional triamcinolone, 5–10 mg/mL into each lesion, works well for scabietic nodules.