A patient presents with a sudden onset of severe vertigo, nausea, vomiting, and nystagmus. The patient reports a recent upper respiratory tract infection. Which of the following conditions is most likely responsible for this presentation?

Correct Answer: A

Rationale: The patient's sudden onset of severe vertigo, nausea, vomiting, and nystagmus following a recent upper respiratory tract infection is consistent with vestibular neuritis. Vestibular neuritis is characterized by acute onset vertigo, often severe, which is typically associated with nausea, vomiting, and nystagmus. The condition is thought to be caused by inflammation of the vestibular nerve, often viral in nature, which can occur following an upper respiratory tract infection. This inflammation leads to dysfunction of the vestibular system in the inner ear, resulting in the symptoms described. Benign paroxysmal positional vertigo (BPPV), characterized by brief episodes of vertigo triggered by specific head movements, is less likely in this case given the sudden onset of symptoms not triggered by head movements. Meniere's disease is characterized by recurrent episodes of vertigo accompanied by hearing loss, tinnitus, and a feeling of fullness

Correct Answer: C

Rationale: The described clinical presentation of a yellowish-white spot on the cornea with a ring of inflammation, along with branching, filamentous opacities extending from the corneal lesion, is highly suggestive of fungal keratitis. Fungal keratitis is commonly caused by filamentous fungi such as Fusarium and Aspergillus species. The characteristic finding of branching, filamentous opacities seen on slit-lamp examination is classic for fungal infections of the cornea. It is important to promptly diagnose and treat fungal keratitis since delayed or inadequate management can result in vision-threatening complications.

Correct Answer: A

Rationale: The clinical presentation described is highly suggestive of acute angle-closure glaucoma. This condition typically presents with sudden-onset severe eye pain, headache, nausea, and vomiting. The red eye, steamy cornea (due to corneal edema), and mid-dilated, non-reactive pupil (from the unopposed force of the dilator muscle) are classic findings in acute angle-closure glaucoma. The increase in intraocular pressure compromises blood flow to the eye, leading to symptoms of blurred vision and possible visual loss. Immediate management usually involves lowering intraocular pressure with medications or surgical intervention to prevent vision loss. Central retinal artery occlusion, optic neuritis, and corneal ulcer typically present with different clinical features and are not consistent with the described presentation.

Correct Answer: B

Rationale: Enamel hypoplasia is a common oral manifestation of celiac disease characterized by defects in the enamel of the teeth. These defects can appear as horizontal or vertical grooves on the teeth. Enamel hypoplasia is caused by disruptions in the formation of enamel during tooth development, leading to thin enamel or localized pitting. It can affect the appearance and strength of the teeth, making them more prone to sensitivity and breakdown. In individuals with celiac disease, enamel hypoplasia may occur due to malabsorption of essential nutrients like calcium and vitamin D. Therefore, when observing oral manifestations such as enamel defects with grooves, it is important to consider the possibility of celiac disease as an underlying cause.

Correct Answer: B

Rationale: The stomach is the organ responsible for the mechanical and chemical digestion of food. When food enters the stomach, it is mixed with stomach acid and enzymes to break down the food into smaller particles. This process helps prepare the food for further digestion and absorption of nutrients. The stomach also plays a key role in the absorption of some nutrients, such as certain vitamins and minerals. Additionally, the stomach's muscular contractions help mix the food with digestive enzymes and propel the partially digested food into the small intestine for further processing and absorption. The liver, pancreas, and large intestine have vital functions in the digestive system, but the stomach is the primary organ responsible for the initial digestion and absorption of nutrients.