A patient presents with well-demarcated, erythematous plaques with silvery scales on the trunk and extensor surfaces of the limbs. The patient reports a family history of similar skin lesions. Which of the following conditions is most likely responsible for this presentation?

Correct Answer: B

Rationale: The patient's presentation of well-demarcated, erythematous plaques with silvery scales on the trunk and extensor surfaces of the limbs is classic for psoriasis. Additionally, the family history of similar skin lesions further supports the diagnosis of psoriasis, as it is a condition with a genetic predisposition. Pityriasis rosea typically presents with a herald patch followed by oval, scaly lesions in a Christmas tree pattern. Erythema multiforme is characterized by target-like lesions. Lichen planus presents as purple, polygonal, flat-topped papules that may have fine white lines on their surface known as Wickham striae.

Correct Answer: A

Rationale: The presentation of well-demarcated, hypopigmented macules with fine scaling on the trunk and proximal extremities is classic for tinea versicolor. Tinea versicolor is a common superficial fungal infection caused by Malassezia spp., which leads to hypo- or hyperpigmented patches on the skin. The condition often occurs in individuals with increased sebum production due to factors such as hot and humid climates, sweating, and oily skin. History of sun exposure and outdoor activities is also commonly reported by patients with tinea versicolor. Treatment usually involves antifungal medications applied topically or taken orally to eliminate the fungus. Differentiating tinea versicolor from other skin conditions, such as vitiligo, pityriasis rosea, or seborrheic keratosis, is important for appropriate management.

Correct Answer: B

Rationale: The clinical scenario described is consistent with a diagnosis of anterior epistaxis due to a prominent vascular lesion located in Little's area, which is an important site for nosebleeds. Silver nitrate cautery is the most appropriate intervention for managing this condition. Silver nitrate cautery is a commonly used method to chemically cauterize and eliminate the friable blood vessels responsible for recurrent epistaxis. It is a cost-effective and minimally invasive technique that can be easily performed in an outpatient setting. Nasal packing with anterior nasal tampons might be considered in cases of severe or refractory epistaxis, but in this scenario, where the source of bleeding is localized and identifiable, silver nitrate cautery is the treatment of choice. Endoscopic cauterization of the sphenopalatine artery and surgical excision of a nasal polyp are unnecessary and overly invasive for the described scenario.

Correct Answer: A

Rationale: Zenker's diverticulum is a condition in which there is a pouch or sac that forms at the posterior pharyngeal wall above the upper esophageal sphincter. It can present with symptoms such as sensation of a foreign body stuck in the throat, difficulty swallowing (dysphagia), and odynophagia (painful swallowing). Flexible laryngoscopy can reveal a submucosal mass arising from the posterior pharyngeal wall, which is characteristic of Zenker's diverticulum.

Correct Answer: A

Rationale: The presentation described with sudden-onset, painless vision loss, a cherry-red spot at the macula, and attenuated retinal vessels is classic for central retinal artery occlusion (CRAO). CRAO occurs when the central retinal artery, which supplies blood to the inner retinal layers, becomes occluded. The cherry-red spot is due to the exposure of the underlying choroid, which still appears red as it is not affected by the blockage. Attenuated retinal vessels and a pale retina may also be seen due to ischemia. In contrast, central retinal vein occlusion (choice B) presents with sudden painless vision loss, retinal hemorrhages, dilated retinal veins, and cotton-wool spots. Retinal detachment (choice C) typically presents with flashes, floaters, and a curtain-like shadow across the vision. Acute angle-closure glaucoma (