DR1.1-2 | Acne — Graded Quiz

Correct. The coexistence of comedones, papules, and pustules across multiple areas without nodules/cysts = IGA Grade 3 (moderate). This grade determines the treatment rung: combined oral antibiotic + topical retinoid ± BPO.

IGA Grade 3 (moderate) = mixed non-inflammatory (comedones) AND inflammatory (papules/pustules) lesions across multiple facial zones, but no nodules or cysts.

Grade 2 is non-inflammatory lesions only. Grade 4 requires nodules or cysts. This patient's mixed inflammatory and non-inflammatory picture fits Grade 3.

Correct. Antibiotic resistance in C. acnes is the most common cause of secondary failure in patients on prolonged antibiotic courses. Adding BPO — which kills C. acnes via oxidative mechanisms that do not select for resistance — is the standard counter-measure and is recommended in all antibiotic-containing regimens.

Prolonged topical or oral antibiotic use without BPO selects for antibiotic-resistant C. acnes strains. BPO added to any antibiotic regimen prevents resistance emergence and can reverse acquired resistance.

Topical retinoids do not cause tachyphylaxis. BPO actually enhances rather than neutralises topical antibiotics when combined. The correct explanation involves antibiotic resistance emerging over time.

Correct. The three-test baseline for isotretinoin in women: fasting lipids (isotretinoin causes hypertriglyceridaemia), LFTs (hepatotoxicity risk), and pregnancy test (teratogenicity). All three must be confirmed normal/negative before prescribing.

Pre-isotretinoin baseline workup: fasting lipid profile (triglycerides especially), liver function tests, and pregnancy test (urine or serum β-hCG) for all females of childbearing potential — monthly thereafter.

Lipids alone miss hepatotoxicity monitoring. Pregnancy test alone misses metabolic monitoring. CBC is not routinely required at baseline (though some guidelines include it) — lipids and LFTs are the core metabolic tests.

Correct. Acne fulminans is a medical emergency: explosive ulcerative acne + systemic features (fever, arthralgia, weight loss, elevated CRP/ESR) appearing after isotretinoin initiation. The drug itself can trigger this paradoxical flare in susceptible individuals, which is why some guidelines recommend starting isotretinoin at low dose (0.25–0.5 mg/kg) in severe cases.

Acne fulminans is a rare, severe complication characterised by sudden-onset ulcerative/haemorrhagic acne, fever, arthralgia, and weight loss — often precipitated by oral isotretinoin initiation. Management requires stopping or reducing isotretinoin and adding systemic corticosteroids.

Acne conglobata lacks the systemic inflammatory features (fever, arthralgia). Secondary infection would show localised signs without systemic systemic arthralgia/weight loss. Gram-negative folliculitis complicates prolonged antibiotic use, not isotretinoin.

Correct. Spironolactone's anti-androgenic effect on the pilosebaceous unit reduces sebum and follicular keratinocyte hyperproliferation. It works in women with both normal and elevated androgens — the sebaceous gland is sensitive to androgen receptor blockade even at normal circulating levels.

Spironolactone is an androgen receptor blocker used in adult female acne. It reduces sebum production and is effective even in women with NORMAL androgen levels. Serum potassium monitoring is required (risk of hyperkalaemia, especially at higher doses).

Spironolactone does not require concurrent OCP (though OCP is often co-prescribed for contraception). It works across the range of androgen levels. Potassium monitoring is mandatory at doses above 100 mg/day.

Correct. Oral antibiotics should not be used beyond 3–6 months. Once inflammatory lesions respond, oral antibiotics are discontinued and the patient is maintained on topical retinoid ± BPO as long-term maintenance.

Oral antibiotics for acne should be time-limited (3–6 months) to prevent antibiotic resistance. Once inflammation is controlled, step down to topical therapy (retinoid ± BPO). Prolonged antibiotic courses are a primary driver of C. acnes resistance.

Indefinite antibiotic use drives resistance. Isotretinoin is not automatically the next step after antibiotics — a step-down to topical therapy is appropriate if response has been good.

Correct. The perioral distribution, vermilion border sparing, absence of comedones, and prolonged topical steroid use are the classic quartet for perioral dermatitis. Treatment involves stopping the topical steroid (expect initial rebound) and using topical metronidazole or tetracyclines.

Perioral dermatitis presents with perioral papulopustules SPARING the vermilion border, NO comedones, triggered or perpetuated by topical corticosteroids. Key differentiators from acne: perioral distribution, steroid history, comedone-free.

Acne vulgaris requires comedones. Steroid acne typically presents with monomorphic papulopustules without vermilion border sparing. Rosacea involves flushing and telangiectasia and does not have the tight perioral distribution with steroid history.

Correct. The retinoid 'purge' (worsening at weeks 2–6) is a well-known, expected phase where microcomedones are rapidly processed and emerge as visible inflammatory lesions. Pre-emptive counselling prevents this being misinterpreted as treatment failure. Full efficacy is typically seen at 8–12 weeks.

Topical retinoids cause an 'initial purging' flare at 2–6 weeks (microcomedones becoming visible inflammatory lesions) before the drug's efficacy is apparent. Patients must be pre-counselled and reassured to continue treatment.

Stopping adapalene at 3 weeks — before efficacy is established — is a common error that denies the patient an effective therapy. The initial flare is not a reason to escalate to oral antibiotics.

Correct. GAGS is a quantitative tool that weights lesion type by anatomical zone (nose = highest factor). A score of 19 falls in the moderate range (19–30), not severe. IGA is simpler for bedside use; GAGS is more granular for research and follow-up.

GAGS divides the face and chest/back into anatomical zones, each with a multiplication factor (weighting) reflecting sebaceous gland density. Lesion type score × zone factor is summed. Mild = 1–18; Moderate = 19–30; Severe = 31–38; Very severe = >38.

GAGS counts both non-inflammatory (comedones score 1) and inflammatory lesions (papules = 2, pustules = 3, nodules = 4). A score of 19 is MODERATE, not severe.

Correct. Isotretinoin is detected in semen only at trace levels (estimated <1 µg/ejaculate) — far below any teratogenic threshold. Males are not required to use condoms or undergo pregnancy-prevention programmes. This is an important counselling point to avoid over-medicalisation of male patients.

The teratogenicity programme (two contraceptive methods, monthly pregnancy tests, 1-month washout) applies to FEMALES only. Males on isotretinoin: isotretinoin in semen is negligible and not considered a teratogenic risk to female partners. Monitoring for males: baseline + periodic lipids and LFTs.

The strict pregnancy-prevention programme (iPLEDGE or local equivalent) is specific to females. Males do not require monthly pregnancy tests or mandatory condom use based on current evidence.