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Module 2 of 3 • 5 min • Clinical Manifestations

When Accounts Get Frozen

“The Six Clinical Domains”

The Big Picture

The fraud detection system has gone rogue. You identified the culprits in Module 1 — the three departments falsely flagging legitimate transactions. But here’s the problem: you didn’t catch them in time. They’ve already started freezing accounts across the bank.

And depending on which branch they hit, the consequences look very different. A frozen checking account is inconvenient. A frozen investment account is devastating. A system-wide crash is catastrophic. The 2023 ACR/EULAR criteria organize these consequences into six clinical domains — six different ways the bank gets hit.

Key Question

What are the six clinical domains of APS, what does each look like, and how do you put the clinical + lab pieces together for classification?

The Six Domains

Domain 1: Checking Accounts — Macrovascular Venous (VTE)

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The most common manifestation. Everyday accounts frozen first.

Domain 2: Investment Accounts — Macrovascular Arterial

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Less common than venous, but the stakes are much higher.

Domain 3: ATM Network — Microvascular Disease

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NEW in 2023 — the distributed network goes down quietly.

Domain 4: Wire Transfer — Obstetric APS

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The critical supply line to the construction project gets cut.

Domain 5: Vault Doors — Cardiac Valve Disease

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New to scored domains in 2023. The vault doors start to malfunction.

Domain 6: Friendly Fire — Hematologic Manifestations

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The fraud system starts targeting the bank’s own employees.

Catastrophic APS — System-Wide Meltdown

The entire banking system crashes. Every branch, every ATM, every portal — frozen simultaneously. Catastrophic APS is the rarest (<1%) and deadliest (30–50% mortality) variant: widespread thrombosis affecting ≥3 organ systems developing over ≤1 week, with small vessel predominance.

Classic triggers: infection, surgery, anticoagulation withdrawal. Treatment = everything deployed at once: anticoagulation + steroids + plasma exchange ± IVIG.

2023 Classification Framework

1
Entry: At least one positive aPL test within 3 years of event
2
Score Clinical: Pick highest-weighted item per domain (D1–D6)
3
Score Lab: LA assays (1–5pts) + aCL/anti-β2GPI ELISA (1–7pts)
4
Classify: Clinical ≥3 AND Lab ≥3 = APS
Key Nuance

2023 criteria traded sensitivity for specificity: 99% specific but 84% sensitive (vs. old Sapporo: 86% specific, 99% sensitive). Some true APS patients won’t meet classification criteria — that’s by design.

Memory Aids

“Three-and-Three to Get the Key” — ≥3 clinical AND ≥3 lab points to classify

“Platelets low but clots still flow — APS paradox, now you know” — Thrombocytopenia in APS means clotting risk, not bleeding risk.

Test Yourself

Q1: A 28-year-old woman with 3 consecutive early pregnancy losses, no thrombosis, LA positive, aCL IgG 62 GPL. Does she meet 2023 criteria?

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Q2: A 35-year-old man with known APS on warfarin undergoes knee surgery. Anticoagulation held. Five days post-op: renal failure, stroke, and ARDS over 48 hours. Diagnosis?

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Q3: A patient with APS has livedo reticularis, proteinuria, and rising creatinine. Biopsy shows thrombotic microangiopathy without immune complex deposition. Diagnosis and significance?

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Summary

  • Six clinical domains: Venous, Arterial, Microvascular (NEW), Obstetric, Cardiac valve (NEW to scoring), Hematologic (NEW to scoring)
  • DVT/PE = most common manifestation; stroke = most common arterial event
  • Young stroke (<50) without risk factors = test aPL
  • Obstetric APS can exist without thrombosis
  • Classification requires ≥3 clinical AND ≥3 lab points
  • CAPS = ≥3 organs in ≤1 week — treat with combination therapy
  • 2023 criteria: 99% specific, 84% sensitive (traded sensitivity for specificity)
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