Acne in Special Populations

Neonatal & Infantile Acne - Tiny Pimple Tales

• Neonatal Acne
  • Onset: Birth to 6 weeks.
  • Etiology: Maternal androgens; Malassezia spp. involvement.
  • Lesions: Inflammatory papules/pustules; NO comedones. Face, scalp.
  • Course: Usually self-resolves; minimal scarring.
  • Tx: Gentle cleansing; topical ketoconazole if needed.
• Infantile Acne
  • Onset: 6 weeks to 12 months.
  • Etiology: Endogenous androgens (infant's ↑ DHEA-S).
  • Lesions: Comedones (key feature!), papules, pustules, nodules.
  • Course: More persistent; higher risk of scarring.
  • Tx: Topical benzoyl peroxide, retinoids. Oral antibiotics if severe.

  ⭐ Infantile acne features comedones, has a higher scarring risk than neonatal acne, and may predict more severe adolescent acne.

Acne in Pregnancy & Lactation - Safe Bump Care

• Goal: Safe symptom control, prioritizing fetal/neonatal well-being.
• Safe Topical Options (Pregnancy Category):
  • Azelaic acid (B)
  • Benzoyl peroxide (C, limited use)
  • Clindamycin (B)
  • Erythromycin (B)
  • Glycolic acid (low conc., AHA)
• Safe Systemic Options (Severe Cases, Pregnancy Category):
  • Oral Erythromycin (B)
  • Cephalexin (B)
  • Zinc
• ⚠️ Strictly Avoid (Teratogenic/Adverse Effects):
  • Topical: All Retinoids (Tretinoin, Adapalene, Tazarotene)
  • Systemic:
    • Oral Isotretinoin (Absolute contraindication, Cat X)
    • Tetracyclines (e.g., Doxycycline, Minocycline - Cat D)
    • Hormonal therapies (Spironolactone, OCPs)
• Lactation:
  • Most topicals generally safe.
  • Systemic: Erythromycin considered safe; others with caution.

⭐ Oral isotretinoin (Cat X) is absolutely contraindicated in pregnancy due to severe teratogenicity.

PCOS & Hormonal Acne - Endocrine Eruptions

• PCOS: Key cause. Features: irregular menses, hirsutism, acne.
  • Rotterdam criteria (2 of 3): Oligo/anovulation, hyperandrogenism (clinical/biochemical), polycystic ovaries on USG.
  • Acne: Mandibular, persistent, perimenstrual flares.
• Hormonal Acne Pattern: "U-zone" (jawline, chin, neck).
  • Associated: SAHA syndrome (Seborrhea, Acne, Hirsutism, Alopecia).
• Workup:
  • Hormones: Testosterone (total/free), DHEAS, LH/FSH.
  • Pelvic USG.
• Management Principles:
  • Target androgens: OCPs (e.g., ethinylestradiol + drospirenone/cyproterone acetate).
  • Anti-androgen: Spironolactone (50-100 mg/day, max 200 mg). ⚠️ Monitor K+.
  • Insulin resistance: Metformin.
  • Standard acne therapies as adjuncts.

⭐ Spironolactone is particularly effective for adult female acne with jawline distribution and premenstrual flares.

Drug-Induced & Occupational Acne - Triggered Breakouts

• Drug-Induced Acne (Acne Medicamentosa):
  • Sudden onset, monomorphic lesions (papulopustules, few comedones).
  • Often on trunk, upper arms.
  • Causative Drugs (📌 "PIMPLES"):
    • Phenytoin
    • Isoniazid, Iodides
    • Medications like antiepileptics (Carbamazepine - not fitting M well, but often grouped)
    • Puromycins, Protease inhibitors
    • Lithium
    • EGFR inhibitors (e.g., Cetuximab), Epidermal growth factor receptor inhibitors
    • Steroids (systemic/topical), Androgens, Anabolic steroids, ACTH.
  • Others: Halogens (bromides, iodides), high-dose Vit B2, B6, B12, Dactinomycin.
• Occupational Acne:
  • Exposure to insoluble, follicle-occluding substances.
  • Chloracne: From halogenated aromatic hydrocarbons (e.g., dioxins, PCBs). Presents with straw-colored cysts, open/closed comedones; typically retroauricular, malar, axillary, groin.
  • Oil Acne: Cutting oils, petroleum products. Comedones, inflammatory papules on exposed areas (forearms, thighs).
  • Tar Acne: Coal tar derivatives. Comedones, folliculitis.
  • Acne Mechanica: Due to friction/pressure (e.g., helmets, straps).

⭐ Chloracne is a severe form of acne caused by exposure to halogenated aromatic compounds (like dioxins) and is characterized by numerous open comedones and straw-colored cysts, often resistant to therapy.

High‑Yield Points - ⚡ Biggest Takeaways

• Neonatal acne: Onset 2-4 weeks, comedones absent, typically self-resolving.
• Infantile acne: Begins 3-6 months, comedones present, may scar; consider endocrine workup if severe.
• Acne in pregnancy: Topical azelaic acid, benzoyl peroxide are safer. Strictly avoid retinoids, tetracyclines.
• Steroid acne: Monomorphic papulopustules, no comedones, follows steroid use.
• Acne fulminans: Severe, ulcerative acne with systemic symptoms (fever, arthralgia); requires systemic steroids first.
• Drug-induced acne: Often monomorphic, caused by steroids, lithium, phenytoin, isoniazid, EGFR inhibitors.