Neurology · LIVE

2024 McDonald criteria for multiple sclerosis

McDonald 2024

Apply Montalban 2025 / 2024 McDonald criteria for typical clinically isolated syndrome and return whether mcdonald_ms holds from caller-assigned typical CIS, no better explanation, attacks, lesions, five DIS topographies (including optic nerve), MRI DIT, CSF-specific oligoclonal bands, and CSF kappa free-light chains.

LIVE $0.005 USDC GET /api/calc/mcdonald_2024

Markdown: /docs/mcdonald-2024.md · Canonical: https://magentlab.com/docs/mcdonald-2024

Not a medical device. Not a diagnosis, dose, or listing recommendation.

What it computes

Apply Montalban 2025 / 2024 McDonald criteria for typical clinically isolated syndrome and return whether mcdonald_ms holds from caller-assigned typical CIS, no better explanation, attacks, lesions, five DIS topographies (including optic nerve), MRI DIT, CSF-specific oligoclonal bands, and CSF kappa free-light chains.

When to use

When an agent already has typical CIS versus not, whether a better explanation exists, ≥2-attack and ≥2-lesion flags, five caller-assigned 2024 DIS topographies, MRI DIT, CSF-specific OCB, and a kappa FLC flag, and needs the published relapsing/CIS combination. magent does not read MRI, OCT, or VEP and does not assay CSF.

When not to use

• Not a medical device and not a diagnosis of multiple sclerosis.
• Relapsing / typical CIS pathway only. Does not implement 2024 primary progressive MS (PPMS) or radiologically isolated syndrome (RIS).
• Not the 2017 McDonald criteria (Thompson 2018). 2024 adds optic nerve as a fifth DIS location and treats kappa free-light chains as interchangeable with oligoclonal bands.
• Does not apply age ≥50 extra specificity requirements, central vein sign, paramagnetic rim lesions, or a 4-of-5 DIT-waive shortcut.
• magent does not read MRI, OCT, or VEP and does not assay CSF. The five topographies, MRI DIT, CSF-specific OCB, and csf_kflc are caller-assigned. csf_kflc is a positive/negative flag, not a numeric kFLC index cutoff.
• Remain vigilant for NMOSD and other better explanations; no_better_explanation is caller-assigned.

Formula

mcdonald_ms iff typical_cis and no_better_explanation and ((two_or_more_attacks and two_or_more_lesions) or (two_or_more_attacks and not two_or_more_lesions and dis) or (not two_or_more_attacks and two_or_more_lesions and (dit_mri or csf_specific_ocb or csf_kflc)) or (not two_or_more_attacks and not two_or_more_lesions and dis and (dit_mri or csf_specific_ocb or csf_kflc))) (Montalban 2025 / 2024 McDonald typical CIS). dis is true iff at least two of periventricular, cortical_or_juxtacortical, infratentorial, spinal_cord, optic_nerve are true. CSF kappa free-light chains are interchangeable with CSF-specific OCB as the CSF DIT substitute. Not PPMS. Not RIS. Not 2017 McDonald. magent does not read MRI, OCT, VEP, or assay CSF. Not a diagnosis

Citation

Title

Diagnosis of multiple sclerosis: 2024 revisions of the McDonald criteria

Authors

Montalban X, Lebrun-Frénay C, Oh J, et al.

Source

Lancet Neurol. 2025;24(10):850-865

DOI

10.1016/S1474-4422(25)00270-4

Worked example

Also searched as

• McDonald criteria 2024
• 2024 McDonald MS diagnosis
• Montalban 2025 McDonald
• CIS dissemination in space optic nerve
• kappa free light chains MS
• McDonald DIS five topographies
• 2024 revisions McDonald criteria
• clinically isolated syndrome 2024

Try

Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.

/api/calc/mcdonald_2024?typical_cis=true&no_better_explanation=true&two_or_more_attacks=true&two_or_more_lesions=true&periventricular=false&cortical_or_juxtacortical=false&infratentorial=false&spinal_cord=false&optic_nerve=false&dit_mri=false&csf_specific_ocb=false&csf_kflc=false

Full URL: https://api.magentlab.com/api/calc/mcdonald_2024?typical_cis=true&no_better_explanation=true&two_or_more_attacks=true&two_or_more_lesions=true&periventricular=false&cortical_or_juxtacortical=false&infratentorial=false&spinal_cord=false&optic_nerve=false&dit_mri=false&csf_specific_ocb=false&csf_kflc=false

Call

Expect HTTP 402 until you retry with PAYMENT-SIGNATURE. Incomplete query params return HTTP 400 before any quote or charge.

curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/mcdonald_2024?typical_cis=true&no_better_explanation=true&two_or_more_attacks=true&two_or_more_lesions=true&periventricular=false&cortical_or_juxtacortical=false&infratentorial=false&spinal_cord=false&optic_nerve=false&dit_mri=false&csf_specific_ocb=false&csf_kflc=false"

Parameters

Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

POST /api/calc/mcdonald_2024 Max 25 unit_amount + extra_item_amount * (n - 1) extra $0.002 PREVIEW

• 1 to 25 items. Each item uses the same keys as the GET query parameters.
• POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
• The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
• HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
• Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
• x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request (fixture)

{
  "items": [
    {
      "cortical_or_juxtacortical": "false",
      "csf_kflc": "false",
      "csf_specific_ocb": "false",
      "dit_mri": "false",
      "infratentorial": "false",
      "no_better_explanation": "true",
      "optic_nerve": "false",
      "periventricular": "false",
      "spinal_cord": "false",
      "two_or_more_attacks": "true",
      "two_or_more_lesions": "true",
      "typical_cis": "true"
    },
    {
      "cortical_or_juxtacortical": "false",
      "csf_kflc": "false",
      "csf_specific_ocb": "false",
      "dit_mri": "false",
      "infratentorial": "false",
      "no_better_explanation": "true",
      "optic_nerve": "false",
      "periventricular": "false",
      "spinal_cord": "false",
      "two_or_more_attacks": "true",
      "two_or_more_lesions": "true",
      "typical_cis": "true"
    }
  ]
}

Open bulk paywall →

Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.

Example 200 (fixture)

{
  "count": 2,
  "path": "/api/calc/mcdonald_2024",
  "items": [
    {
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Montalban X, Lebrun-Frénay C, Oh J, et al.",
        "doi": "10.1016/S1474-4422(25)00270-4",
        "id": "montalban-2025",
        "pmid": "40975101",
        "source": "Lancet Neurol. 2025;24(10):850-865",
        "title": "Diagnosis of multiple sclerosis: 2024 revisions of the McDonald criteria"
      },
      "formula": "mcdonald_2024",
      "formula_expression": "mcdonald_ms iff typical_cis and no_better_explanation and ((two_or_more_attacks and two_or_more_lesions) or (two_or_more_attacks and not two_or_more_lesions and dis) or (not two_or_more_attacks and two_or_more_lesions and (dit_mri or csf_specific_ocb or csf_kflc)) or (not two_or_more_attacks and not two_or_more_lesions and dis and (dit_mri or csf_specific_ocb or csf_kflc))) (Montalban 2025 / 2024 McDonald typical CIS). dis is true iff at least two of periventricular, cortical_or_juxtacortical, infratentorial, spinal_cord, optic_nerve are true. CSF kappa free-light chains are interchangeable with CSF-specific OCB as the CSF DIT substitute. Not PPMS. Not RIS. Not 2017 McDonald. magent does not read MRI, OCT, VEP, or assay CSF. Not a diagnosis",
      "criteria": [
        {
          "factor": "typical_cis",
          "met": true
        },
        {
          "factor": "no_better_explanation",
          "met": true
        },
        {
          "factor": "two_or_more_attacks",
          "met": true
        },
        {
          "factor": "two_or_more_lesions",
          "met": true
        },
        {
          "factor": "periventricular",
          "met": false
        },
        {
          "factor": "cortical_or_juxtacortical",
          "met": false
        },
        {
          "factor": "infratentorial",
          "met": false
        },
        {
          "factor": "spinal_cord",
          "met": false
        },
        {
          "factor": "optic_nerve",
          "met": false
        },
        {
          "factor": "dis",
          "met": false
        },
        {
          "factor": "dit_mri",
          "met": false
        },
        {
          "factor": "csf_specific_ocb",
          "met": false
        },
        {
          "factor": "csf_kflc",
          "met": false
        },
        {
          "factor": "relapsing_cis_pathway",
          "met": true
        },
        {
          "factor": "mcdonald_ms",
          "met": true
        }
      ],
      "cortical_or_juxtacortical": false,
      "csf_kflc": false,
      "csf_specific_ocb": false,
      "dis": false,
      "dit_mri": false,
      "infratentorial": false,
      "mcdonald_ms": true,
      "no_better_explanation": true,
      "optic_nerve": false,
      "periventricular": false,
      "spinal_cord": false,
      "two_or_more_attacks": true,
      "two_or_more_lesions": true,
      "typical_cis": true
    },
    {
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Montalban X, Lebrun-Frénay C, Oh J, et al.",
        "doi": "10.1016/S1474-4422(25)00270-4",
        "id": "montalban-2025",
        "pmid": "40975101",
        "source": "Lancet Neurol. 2025;24(10):850-865",
        "title": "Diagnosis of multiple sclerosis: 2024 revisions of the McDonald criteria"
      },
      "formula": "mcdonald_2024",
      "formula_expression": "mcdonald_ms iff typical_cis and no_better_explanation and ((two_or_more_attacks and two_or_more_lesions) or (two_or_more_attacks and not two_or_more_lesions and dis) or (not two_or_more_attacks and two_or_more_lesions and (dit_mri or csf_specific_ocb or csf_kflc)) or (not two_or_more_attacks and not two_or_more_lesions and dis and (dit_mri or csf_specific_ocb or csf_kflc))) (Montalban 2025 / 2024 McDonald typical CIS). dis is true iff at least two of periventricular, cortical_or_juxtacortical, infratentorial, spinal_cord, optic_nerve are true. CSF kappa free-light chains are interchangeable with CSF-specific OCB as the CSF DIT substitute. Not PPMS. Not RIS. Not 2017 McDonald. magent does not read MRI, OCT, VEP, or assay CSF. Not a diagnosis",
      "criteria": [
        {
          "factor": "typical_cis",
          "met": true
        },
        {
          "factor": "no_better_explanation",
          "met": true
        },
        {
          "factor": "two_or_more_attacks",
          "met": true
        },
        {
          "factor": "two_or_more_lesions",
          "met": true
        },
        {
          "factor": "periventricular",
          "met": false
        },
        {
          "factor": "cortical_or_juxtacortical",
          "met": false
        },
        {
          "factor": "infratentorial",
          "met": false
        },
        {
          "factor": "spinal_cord",
          "met": false
        },
        {
          "factor": "optic_nerve",
          "met": false
        },
        {
          "factor": "dis",
          "met": false
        },
        {
          "factor": "dit_mri",
          "met": false
        },
        {
          "factor": "csf_specific_ocb",
          "met": false
        },
        {
          "factor": "csf_kflc",
          "met": false
        },
        {
          "factor": "relapsing_cis_pathway",
          "met": true
        },
        {
          "factor": "mcdonald_ms",
          "met": true
        }
      ],
      "cortical_or_juxtacortical": false,
      "csf_kflc": false,
      "csf_specific_ocb": false,
      "dis": false,
      "dit_mri": false,
      "infratentorial": false,
      "mcdonald_ms": true,
      "no_better_explanation": true,
      "optic_nerve": false,
      "periventricular": false,
      "spinal_cord": false,
      "two_or_more_attacks": true,
      "two_or_more_lesions": true,
      "typical_cis": true
    }
  ]
}

Response

Example JSON

Machine form of the same example. Frozen fixture. Not a live lookup.

{
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Montalban X, Lebrun-Frénay C, Oh J, et al.",
    "doi": "10.1016/S1474-4422(25)00270-4",
    "id": "montalban-2025",
    "pmid": "40975101",
    "source": "Lancet Neurol. 2025;24(10):850-865",
    "title": "Diagnosis of multiple sclerosis: 2024 revisions of the McDonald criteria"
  },
  "formula": "mcdonald_2024",
  "formula_expression": "mcdonald_ms iff typical_cis and no_better_explanation and ((two_or_more_attacks and two_or_more_lesions) or (two_or_more_attacks and not two_or_more_lesions and dis) or (not two_or_more_attacks and two_or_more_lesions and (dit_mri or csf_specific_ocb or csf_kflc)) or (not two_or_more_attacks and not two_or_more_lesions and dis and (dit_mri or csf_specific_ocb or csf_kflc))) (Montalban 2025 / 2024 McDonald typical CIS). dis is true iff at least two of periventricular, cortical_or_juxtacortical, infratentorial, spinal_cord, optic_nerve are true. CSF kappa free-light chains are interchangeable with CSF-specific OCB as the CSF DIT substitute. Not PPMS. Not RIS. Not 2017 McDonald. magent does not read MRI, OCT, VEP, or assay CSF. Not a diagnosis",
  "criteria": [
    {
      "factor": "typical_cis",
      "met": true
    },
    {
      "factor": "no_better_explanation",
      "met": true
    },
    {
      "factor": "two_or_more_attacks",
      "met": true
    },
    {
      "factor": "two_or_more_lesions",
      "met": true
    },
    {
      "factor": "periventricular",
      "met": false
    },
    {
      "factor": "cortical_or_juxtacortical",
      "met": false
    },
    {
      "factor": "infratentorial",
      "met": false
    },
    {
      "factor": "spinal_cord",
      "met": false
    },
    {
      "factor": "optic_nerve",
      "met": false
    },
    {
      "factor": "dis",
      "met": false
    },
    {
      "factor": "dit_mri",
      "met": false
    },
    {
      "factor": "csf_specific_ocb",
      "met": false
    },
    {
      "factor": "csf_kflc",
      "met": false
    },
    {
      "factor": "relapsing_cis_pathway",
      "met": true
    },
    {
      "factor": "mcdonald_ms",
      "met": true
    }
  ],
  "cortical_or_juxtacortical": false,
  "csf_kflc": false,
  "csf_specific_ocb": false,
  "dis": false,
  "dit_mri": false,
  "infratentorial": false,
  "mcdonald_ms": true,
  "no_better_explanation": true,
  "optic_nerve": false,
  "periventricular": false,
  "spinal_cord": false,
  "two_or_more_attacks": true,
  "two_or_more_lesions": true,
  "typical_cis": true
}

Client errors (HTTP 400)

Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.

Related tools

• McDonald 2017 — Apply Thompson 2018 / 2017 McDonald criteria for typical clinically isolated syndrome and return whether mcdonald_ms holds from caller-assigned typical CIS, no better explanation, attacks, lesions, DIS, MRI DIT, and CSF-specific oligoclonal bands.

Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. Unpaid valid requests return HTTP 402 with a base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake and shared payment errors: Payments. Stdio MCP: /docs/mcp.

Guarantees

• HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
• exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
• HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
• Execution is timeout-bounded and concurrency-capped.
• Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.