Scabies: Symptoms, Diagnosis, and Treatment

Here is the information extracted and converted to markdown format: ### Scabies **Pathogen**: Sarcoptes scabiei. Highly contagious and transmitted via direct physical (skin-to-skin or sexual) contact. The excretions of the mites and their decomposing bodies contain antigens which cause an immuno...

Here is the information extracted and converted to markdown format: ### Scabies **Pathogen**: Sarcoptes scabiei. Highly contagious and transmitted via direct physical (skin-to-skin or sexual) contact. The excretions of the mites and their decomposing bodies contain antigens which cause an immunological response (see type IV hypersensitivity reaction) **Signs and symptoms**: A pimple-like rash, burrows, and intense itching that worsens at night. **Predilection sites**: Inter digital folds, Male genitalia. **Confirmed by**: Requires direct visualization of the mites or their eggs or feces using a dermatoscope **Medical therapy**: topical application of a scabicidal agent permethrin 5% lotion **Alternatives treatment**: Oral ivermectin. **Prevention**: Wash all textiles (e.g., clothing and bedding) AND all contacts within the household should be treated for scabies infestation even if asymptomatic. **Image**: A close up photograph of a hand, with arrows pointing to two small red bumps. **Case 1:** A 4-year-old boy is brought to the physician by his mother because of a rash on his hands and feet for the past 2 weeks. The rash is intensely pruritic, especially at night. He has not had fever, headache, or diarrhea. His mother has a history of eczema. The child was due for an appointment later in the week to follow up on any potentially missing vaccinations. His temperature is 37.0°C (98.6°F). Examination shows a maculopapular rash with linear tracks affecting the interdigital spaces of the fingers and toes. The remainder of the examination shows no abnormalities **Case 2:** A previously healthy 26-year-old man comes to the physician because of a 1-week history of pruritic rash. Initially, he noticed a set of small, red "bumps" in a linear pattern along his arm. Although these started to recede after a few days, he found another set of similar lesions in clusters on his back yesterday morning. The itching is worse at night. His roommates have also developed similar rashes since moving into their new apartment in San Francisco 2 weeks ago. There are no pets at home. His temperature is 36.8°C (98.4°F), pulse is 70/min, and blood pressure is 108/70 mm Hg. A photograph of the patient's rash is shown. The remainder of the physical examination shows no abnormalities. 1. **Diagnosis**: Scabies 2. **Confirm**: Direct visualization of the mites or their eggs or feces using a dermatoscope. 3. **Treatment**: Topical permethrin is the first-line treatment. 4. **Prevention**: Prophylactic treatment of all close contacts.