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Dermatomyositis is an inflammatory myopathy characterized by proximal muscle weakness and characteristic skin findings such as heliotrope rash (violaceous periorbital rash) and Gottron papules (raised erythematous lesions over knuckles). Polymyositis presents with muscle weakness but lacks skin findings. Polymyalgia rheumatica causes pain and stiffness in shoulders/hips in older adults, often associated with temporal arteritis, but no rash. Systemic sclerosis causes skin thickening and internal organ fibrosis. Dermatomyositis is associated with malignancy (ovarian, lung, colorectal) in adults. Labs show elevated CK and aldolase; biopsy reveals perifascicular atrophy with perimysial inflammation. Treatment includes corticosteroids and immunosuppressants.

Cushing disease is caused by an ACTH-secreting pituitary adenoma. Patients present with central obesity, moon facies, purple striae, muscle wasting, hypertension, and glucose intolerance. The dexamethasone suppression test differentiates causes: low-dose dexamethasone fails to suppress cortisol in all Cushing syndromes; high-dose dexamethasone suppresses cortisol in pituitary adenomas but not in adrenal tumors or ectopic ACTH production. Adrenal adenomas cause ACTH-independent Cushing syndrome, with low ACTH. Ectopic ACTH production (e.g., small cell lung carcinoma) does not suppress with high-dose dexamethasone. Exogenous glucocorticoid use suppresses ACTH and causes adrenal atrophy. MRI confirms pituitary adenoma. Treatment involves surgical resection or medical therapy (ketoconazole, metyrapone).

Leydig cell tumors are rare testicular stromal tumors that can produce testosterone or estrogen. They present with gynecomastia in men or precocious puberty in boys. Histology shows large polygonal cells with eosinophilic cytoplasm and rod-shaped intracytoplasmic inclusions called Reinke crystals, which are pathognomonic. Seminomas are germ cell tumors presenting with painless testicular enlargement but not hormone production. Yolk sac tumors (endodermal sinus tumors) occur in children, with elevated alpha-fetoprotein (AFP) and Schiller–Duval bodies. Teratomas contain tissues from multiple germ layers and may be benign or malignant. Leydig cell tumors are usually benign but can be malignant in some cases. Orchiectomy is curative for benign tumors.

Polycystic ovary syndrome (PCOS) features hyperandrogenism, oligo-ovulation/anovulation, and polycystic ovarian morphology; insulin resistance is common. For patients seeking pregnancy, the first-line ovulation induction agent is an aromatase inhibitor such as letrozole, which lowers estrogen synthesis and releases hypothalamic-pituitary negative feedback, increasing FSH secretion and promoting follicular development. Randomized trials demonstrate higher ovulation and live-birth rates with letrozole versus clomiphene in PCOS, particularly in patients with obesity. Metformin improves insulin sensitivity and can restore ovulation in some, but as monotherapy it is less effective for fertility than letrozole; it is useful adjunctively in metabolic syndrome or impaired glucose tolerance. Combined oral contraceptives and progestin IUDs regulate bleeding and protect the endometrium in anovulatory patients not attempting conception but suppress ovulation, counterproductive to current goals. Lifestyle modification (weight reduction, exercise) remains foundational, as modest weight loss can significantly improve ovulatory function and treatment success. Monitoring for multifollicular development and counseling about multiple gestation risk are appropriate during pharmacologic induction.

Autonomy refers to a patient’s right to make informed decisions about their own healthcare. Providing a placebo without disclosure undermines informed consent and violates autonomy, even if the physician intends to benefit the patient. Beneficence (acting in the patient’s best interest) and nonmaleficence (avoiding harm) may be cited by physicians who justify placebo use, but these cannot override autonomy without informed consent. Justice relates to fairness in resource allocation, not placebo use. Ethical medical practice requires honesty and transparency. If placebos are used, it should be with patient knowledge and consent, such as in clinical trials. Deceptive use erodes trust in the physician-patient relationship and violates ethical and professional standards.