WBR0535
Jump to navigation
Jump to search
| Author | [[PageAuthor::Yazan Daaboul, M.D. (Reviewed by Serge Korjian)]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Pathology |
| Sub Category | SubCategory::Dermatology, SubCategory::Neurology |
| Prompt | [[Prompt::A 74-year-old man presents to the out-patient clinic complaining of a new scalp lesion. The patient reports his only medication as ropirinole, which has been well-tolerated. Physical examination reveals the lesion shown in the image below. The physician notices a tremor at rest, muscle twitches upon active bending of the limb, and bradykinesia. What is the most likely diagnosis of the patient's scalp lesion?
|
| Answer A | AnswerA::Tinea corporis |
| Answer A Explanation | [[AnswerAExp::Candida albicans is not commonly associated with Parkinson's disease. Howevever, candida albicans, similar to seborrheic dermatitis, is also a fungal inflammation of the skin that causes erythema and should be considered in the differential diagnosis of seborrheic dermatitis.]] |
| Answer B | AnswerB::Eczema |
| Answer B Explanation | AnswerBExp::Eczema is a type of dermatitis that is often a scaling lesion located at skin flexures. It is commonly found in children with atopy, such as asthma. It is not commonly associated with Parkinson's disease. |
| Answer C | AnswerC::Psoriasis |
| Answer C Explanation | [[AnswerCExp::Psoriasis is a silvery scaling papule or plaque that should always be considered in the differential diagnosis of seborrheic dermatitis. It is characterized by increase in the stratum spinosum layer of the skin and a decrease of the stratum granulosum. Psoriasis commonly presents in younger individuals. A positive Auspitz sign, defined as bleeding when scaled are scraped off, is characteristic on physical exam. Psoriasis is not commonly associated with Parkinson's disease.]] |
| Answer D | AnswerD::Urticaria |
| Answer D Explanation | AnswerDExp::Urticaria or hives is a skin manifestation of allergic conditions that is characterized by raised erythematous itchy wheals with central clearing. |
| Answer E | AnswerE::Seborrheic dermatitis |
| Answer E Explanation | AnswerEExp::Seborrheic dermatitis is an inflammatory skin disease caused by Malassezia furfur. It is associated with Parkinson's disease. |
| Right Answer | RightAnswer::E |
| Explanation | [[Explanation::Seborrheic dermatitis is an inflammatory skin disease with sebum secretions due to the Malassezia furfur fungus that occurs most often on the face, scalp, and chest. On histologic examination, seborrheic dermatitis is best characterized by parakeratosis (retained nuclei in stratum corneum), orthokeratosis (formation of anuclear keratin layer), and follicular plugs. Cyclical "squirting" of granulocytes from the dermal papilla may also be observed. Seborrheic dermatitis is best treated using any of several topical antifungal medications and keratinolytic agents, such as selenium sulphide. The patient presents with physical examination findings that suggest Parkinson's disease; which is also confirmed by the use of ropirinole, a non-ergotamine dopamine agonist. Patients with Parkinson's disease often have resting or "pill-rolling" tremor, cogwheel rigidity upon active flexion of the limbs, and bradykinesia. The association between Parkinson's disease and seborrheic dermatitis is well established; however, the pathophysiology is poorly understood. The level of seborrhea, however, does not seem to correlate with the degree of Parkinson's disease. Other factors associated with seborrheic dermatitis are HIV/AIDS, mood disorders, and winter weather. Educational Objective: Seborrheic dermatitis is an inflammatory skin condition that commonly affects the face, scalp, and chest. It is caused by Malassezia furfur and is commonly associated with Parkinson's disease. |
| Approved | Approved::Yes |
| Keyword | WBRKeyword::Seborrheic dermatitis, WBRKeyword::Parkinson's disease, WBRKeyword::Cogwheel rigidity, WBRKeyword::Bradykinesia, WBRKeyword::Resting tremor, WBRKeyword::Tremor, WBRKeyword::Malassezia furfur |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |
