Reasoning GP · Algorithm · 1-page summary
Bruising — easy or unexplained
For: adults with new, recurrent or unexplained bruising, including those on antiplatelets or anticoagulants. Not for: children, who need a separate paediatric and safeguarding pathway (block 1 shows the immediate route only). Follow local haematology, anticoagulation and safeguarding pathways.
Core rule: two things you cannot miss — leukaemia and maltreatment. Get an FBC and a full medicine history; never stop an antithrombotic reflexively, and never start steroids for low platelets.
0Stop — call 999 now — do not delay transfer for GP tests
- Major or critical-site bleeding (intracranial, GI, retroperitoneal), haematemesis, melaena, significant haemoptysis, syncope or haemodynamic compromise → 999
- Severe headache, neurological symptoms, collapse or reduced consciousness with low platelets or an anticoagulant; non-blanching rash with fever or seriously unwell (meningococcal) → 999
- Suspected DIC or thrombotic microangiopathy with systemic illness; rapidly expanding deep haematoma, airway-threatening oral bleeding or suspected compartment syndrome → 999
- While waiting: no reversal in primary care; record anticoagulant, dose, time of last dose, renal function.
1Triage — who is in front of you
| Patient | Action |
|---|---|
| Child | Non-mobile, protected sites, patterned or unexplained → Urgent senior paediatric / safeguarding (CG89); consider medical causes too. Unexplained petechiae or hepatosplenomegaly → Immediate specialist. |
| Anticoagulated | Major → 999; significant → Same-day hospital; minor → INR, adherence, renal function, interactions. |
| Frail adult | Consider abuse: ask about safety at home → adult safeguarding if concerned. |
2Screen — local platelet thresholds, not NICE
- Platelets <20 × 10⁹/L; oral blood blisters, mucosal bleeding, widespread petechiae → Same-day haematology.
- Blasts, pancytopenia, film suggesting leukaemia → Immediate specialist.
- Bruising + pallor, fatigue, fever, infections, nodes or hepatosplenomegaly → consider very urgent FBC ≤48 h (NG12); weight loss, sweats + nodes → consider lymphoma referral.
- Spontaneous deep haematoma or haemarthrosis; suspected HIT; significant bleeding on an antithrombotic → Same-day
- Platelets <50 or falling → same-day or Urgent; 50–100 stable or unexplained abnormal PT/APTT → Urgent advice.
3Assess — once blocks 0–2 are answered
☐ Superficial, mucosal (platelets, VWD) vs deep, joints, delayed (coagulation) ☐ All medicines incl. OTC, herbal; alcohol ☐ Lifelong? Dental, surgical, family, menstrual bleeding ☐ Petechiae, oral blisters, nodes, liver, spleen, joints, skin, neurology ☐ FBC ± film, U&E, LFT; PT/APTT/fibrinogen if significant or unexplained bleeding. Not here: PFA-100, D-dimer, routine VWD studies, marrow biopsy.
4Classify — mechanism, then next step
- Actinic / steroid purpura — fragile sun-damaged forearms, no bleeding history → reassure; reconsider if atypical.
- Drug-induced — new drug (e.g. quinine, heparin, valproate, trimethoprim) → review it; FBC.
- ITP — isolated platelets <100, normal clotting, other causes excluded → discuss with haematology.
- Inherited (VWD, haemophilia) — lifelong; normal tests do not exclude VWD → haematology.
- Acquired coagulopathy (liver, vitamin K, DIC); vascular — IgA vasculitis (palpable purpura), scurvy, Ehlers-Danlos.
- Uncertain / "easy bruising" — benign only after normal FBC and clotting, no bleeding history.
5Treat today — only these
- Antithrombotics: weigh indication and thrombotic risk before stopping. Aspirin not indicated → stop; NSAID → paracetamol.
- Warfarin: INR 5–8, no bleeding → omit 1–2 doses, reduce, recheck promptly. INR >8, no bleeding → stop, oral vitamin K, recheck ≤24 h. Minor bleeding, INR >5 → Same-day vitamin K. Local protocol; doses: NICE/SPC, BNF, local formulary.
- DOAC, minor bruising: adherence, dose, CrCl, interactions; avoid NSAIDs; no PT/APTT.
- Never here: prednisolone for low platelets; desmopressin for suspected VWD. Scurvy → ascorbic acid per local guidance.
6Refer routinely — and follow up
- Convincing bleeding history → haematology, even if tests are normal. Stable VWD; stable ITP (platelets >50).
- Atypical or ulcerated purpura → dermatology.
- Follow-up: drug stopped → FBC at 1 week; confirm cancer appointment received; DOAC → CrCl at least yearly.
7Never reassure by
- Normal FBC and clotting, or no family history, when the bleeding history is convincing.
- "Easy bruising" in a baby who is not mobile, or on a child's ears, neck, cheeks or buttocks.
- Labelling bruising in a frail adult as age or falls without asking about safety at home.
- Treating low platelets as ITP before haematology has excluded leukaemia.
8Safety-net — verbal and written, then document it
999 “Call 999 for a severe headache, confusion, collapse or new weakness; vomiting blood, black stools or coughing up blood; heavy bleeding or feeling faint; a rash that does not fade with fever or feeling very unwell; or a very swollen joint with numbness.” Any head injury on an anticoagulant → A&E straight away, even if well. Same day “Contact us or NHS 111 today for new widespread pin-point spots, blood blisters in the mouth, bleeding that won't stop with pressure, a nosebleed over 10–15 minutes (A&E), bruises spreading fast, blood in urine or from the back passage, a new swollen muscle or joint, or bruising with fever, paleness, marked tiredness, swollen glands or weight loss.”
Anticoagulants: know the medicine, dose and indication; carry an alert card.
✓Safe to leave primary care only if — all five, documented
No block 0 or same-day row applies
Safeguarding considered (child or adult at risk)
All medicines reviewed; none stopped reflexively
FBC ± film and clotting requested; result owner named
Verbal and written safety-net given
Summary of the full Reasoning GP bruising algorithm (detail and evidence). Sources: NICE NG12 (updated April 2026), CG89, TA697, NG88; UKHCDO/BSH VWD (2024); BSH ITP and platelet transfusion guidance; SPS anticoagulant monitoring; MHRA. Clinical reference — follow local pathways and check doses: NICE/SPC, BNF.