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Acne Vulgaris

Also known as: Pimples, Acne

Acne Vulgaris

Chronic inflammatory disorder of the pilosebaceous unit driven by androgen-mediated sebum overproduction, follicular hyperkeratinization, Cutibacterium acnes colonization, and inflammation.

Most common in adolescence (~85% of 12–24y) but increasingly seen in adult-onset (especially females, 25–40y).

Classified by:

  • Morphology: comedonal (non-inflammatory: open/closed comedones), papulopustular (inflammatory), nodulocystic (severe, deep-seated nodules/cysts)

  • Severity: mild / moderate / severe (grading systems: Global Acne Grading System, Investigator's Global Assessment)

  • Special variants: acne conglobata (severe, interconnecting nodules/sinus tracts), acne fulminans (acute, ulcerative, with systemic symptoms; fever, arthralgia, leukocytosis), neonatal/infantile acne, acne mechanica (friction-induced), drug-induced acne (steroids, lithium, isoniazid, phenytoin, EGFR inhibitors), and PCOS-associated acne.

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Continue reading · Internal medicine

Valvular Heart Disease

Valvular Heart Disease

Valvular heart disease refers to structural or functional abnormality of one or more of the four cardiac valves, causing either stenosis (obstruction to forward flow) or regurgitation (backward leakage of blood), or a combination of both.

Aortic stenosis, most commonly degenerative and calcific in older adults (though congenital bicuspid aortic valve predisposes to earlier onset stenosis) or rheumatic in origin in endemic settings, is the most common valve lesion requiring intervention in high income countries.

Mitral regurgitation arises from primary valve pathology (degenerative mitral valve prolapse, rheumatic disease, infective endocarditis) or secondary functional regurgitation from left ventricular dilation distorting the normal valve geometry.

Aortic regurgitation results from either primary valve leaflet disease (bicuspid valve, rheumatic disease, endocarditis) or aortic root dilation (hypertension, aortopathy, connective tissue disease such as Marfan syndrome).

Mitral stenosis is overwhelmingly rheumatic in origin, remaining an important cause of valve disease in regions with ongoing rheumatic fever burden (see Rheumatic Fever entry).