Ever had a patient come in with vague joint pain, rash, and fatigue — but no classic SLE red flags? And then, just when your rheumatology brain is warming up, the ANA comes back positive and anti-dsDNA is negative?
Welcome to the wild world of drug-induced lupus (DIL) — the sneaky imposter of systemic lupus erythematosus. 😈
Luckily, there’s a mnemonic that helps you dock the right diagnosis:
🛳 SHIPPE — the offending meds that sail straight into lupus waters.
Drug Induced Lupus Causes Mnemonic
| Letter | Drug | Mechanism / Notes |
|---|---|---|
| S | Sulphonamides | Hypersensitivity-mediated autoimmunity |
| H | Hydralazine | Vasodilator – notorious for lupus in slow acetylators 💊 |
| I | Isoniazid | TB drug – check ANA if symptoms emerge during therapy |
| P | Procainamide | Antiarrhythmic – one of the highest risk DIL culprits ⚠️ |
| P | Phenytoin | Anticonvulsant – think of it in patients with rash + fever + joint pain |
| E | Etanercept | TNF-α inhibitor – irony? Causes lupus while treating autoimmune disease 🌀 |
🏥 Clinical Pearls from the Wards in Quetta
At Sheikh Khalifa Bin Zayed Hospital, we had a middle-aged woman on hydralazine for uncontrolled hypertension. Two months in, she developed arthralgia, low-grade fever, and a malar-ish rash.
- ANA? Positive.
- Anti-dsDNA? Negative.
- Anti-histone antibodies? Sky high. 🚨
- Diagnosis? Hydralazine-induced lupus.
She improved dramatically after stopping the drug — like watching someone drop a toxic relationship and glow up. 💅
🔬 How to Clinch the Diagnosis
- Anti-histone antibodies are positive in >95% of drug-induced cases.
- Anti-dsDNA and anti-Sm are usually negative (unlike in SLE).
- Symptoms resolve after stopping the culprit drug — think of it as medical ghosting. 👻
- Common features: arthralgia, fever, rash, serositis, but renal/CNS involvement is rare.
🧠 For the USMLE + Clinical Exams
- Hydralazine + lupus symptoms? Jump on it.
- TB patient on isoniazid with joint pain? SHIPPE alert.
- TNF inhibitor causing lupus? Yes, Etanercept can betray its autoimmune comrades.
- Remember: “anti-histone positive = drug-induced until proven otherwise.”
Happy learning, folks!
Authored by:
Dr. Aurangzaib Qambrani
(MBBS, PLAB, MRCP-UK Part 1)
Sheikh Khalifa Bin Zayyed Hospital, Quetta
