A patient presents with a painful, vesicular rash in a dermatomal distribution on the left thorax. The patient reports a history of chickenpox during childhood. Which of the following conditions is most likely responsible for this presentation?

Correct Answer: B

Rationale: The presentation of a painful, vesicular rash in a dermatomal distribution on the left thorax, specifically in a patient with a history of chickenpox, is most suggestive of herpes zoster, commonly known as shingles. Herpes zoster is caused by the reactivation of the varicella-zoster virus, the same virus responsible for chickenpox. After a person recovers from chickenpox, the virus remains dormant in the nerve cells and can reactivate years later to cause shingles. The rash in herpes zoster typically progresses through different stages, including red patches leading to fluid-filled blisters. The characteristic rash typically appears unilaterally and is usually preceded by pain, burning, or tingling in the affected area. Unlike herpes simplex virus infection, which can cause similar lesions but is not typically localized to a specific dermatome, herpes zoster presents as a distinct unilateral cluster of vesicles along

Correct Answer: A

Rationale: The patient's presentation of a pruritic, annular rash with fine scaling and central clearing, affecting the trunk and proximal extremities, following exposure to a new soap and laundry detergent is most consistent with tinea corporis, commonly known as ringworm. Ringworm is a superficial fungal infection caused by dermatophytes that can present with circular or annular lesions with central clearing and scaling. The exposure to new soap and laundry detergent may have disrupted the skin's microbiome, making it more vulnerable to fungal infections like tinea corporis. Nummular eczema typically presents as coin-shaped plaques rather than annular lesions, while pityriasis rosea presents with a herald patch followed by smaller similar lesions in a "Christmas tree" distribution. Lichen planus would not typically be associated with exposure to new soap and laundry detergent but can have distinct purple, polygonal papules.

Correct Answer: A

Rationale: The presentation of a palpable, non-tender mass in the right neck, just below the angle of the mandible, along with ultrasound imaging findings of a well-defined, hypoechoic lesion with cystic components, is classic for a branchial cleft cyst. Branchial cleft cysts are congenital anomalies that arise from remnants of the branchial clefts or pouches during embryonic development. They are typically located along the anterior border of the sternocleidomastoid muscle, just below the mandible. Ultrasound imaging often shows a cystic lesion with well-defined borders and hypoechoic content, which is consistent with the described findings. Thyroglossal duct cysts usually present as midline neck masses that move with swallowing or tongue protrusion, not in the location described in the scenario. Lymphadenopathy would present as enlarged lymph nodes that may be tender and associated with systemic symptoms.

Correct Answer: B

Rationale: Ramsay Hunt syndrome is caused by the varicella-zoster virus affecting the geniculate ganglion, leading to a triad of symptoms known as the Hunt syndrome: facial paralysis, ear pain, and a vesicular rash in the ear or palate. The facial paralysis in Ramsay Hunt syndrome is usually peripheral, similar to Bell's palsy, but may be more severe. In addition to facial paralysis, the patient may have the inability to close the eye on the affected side (lagophthalmos) and loss of taste sensation on the anterior two-thirds of the tongue due to involvement of the chorda tympani nerve. This differentiation is important to consider in the context of our patient's presentation.

Correct Answer: A

Rationale: The presentation described is consistent with acute angle-closure glaucoma. This condition typically presents with sudden-onset severe eye pain, headache, nausea, and vomiting. On examination, the affected eye appears red, with a steamy cornea due to corneal edema and a mid-dilated, non-reactive pupil due to pupillary block from the forward displacement of the iris. Acute angle-closure glaucoma is considered a medical emergency as it can lead to permanent vision loss if not promptly treated. Prompt management involves reducing intraocular pressure to prevent further damage to the optic nerve.