Final answer:
Seborrheic dermatitis is an inflammatory skin condition typified by erythematous plaques in areas rich in sebum and is associated with conditions like Parkinson's disease and HIV/AIDS in middle age. It does not typically present with pustules, bullous, or targetoid lesions unlike other skin disorders such as acne or psoriasis. Treatments focus on reducing inflammation and controlling yeast growth.
Step-by-step explanation:
Seborrheic dermatitis is a common inflammatory skin condition characterized by scaly, erythematous plaques that typically occur in areas with a high concentration of sebaceous (oil-producing) glands. This includes the scalp, face, chest, and back. The correct description and associated conditions in middle age are: Seborrheic dermatitis: Scaly, erythematous plaques in sebum-rich areas; Associated conditions: Parkinson's disease, HIV/AIDS.
Aside from these associations, seborrheic dermatitis can also be seen alongside other conditions but is primarily known for its link to Parkinson's disease and HIV/AIDS. Lesions are not typically pustular as in some presentations of acne, nor do they form bullous or targetoid lesions that are more characteristic of other skin disorders such as psoriasis or Sjögren's syndrome.
In the context of middle-aged individuals, these connections might be significant, since the prevalence of seborrheic dermatitis can increase or the condition can become more severe with conditions that affect the immune system or neurological health. Treatments for seborrheic dermatitis often include antifungal creams, medicated shampoos, and topical steroids aimed at reducing inflammation and controlling yeast growth that may exacerbate the condition.