---
name: aosd-activity
description: Adult-onset Still disease activity and systemic severity scoring with Pouchot-style systemic features, MAS warning heuristics, and treatment-intensity interpretation for RheumaScore publishing.
---

# AOSD-ACTIVITY

AOSD-ACTIVITY computes a transparent adult-onset Still disease activity summary centered on the 12-item systemic score used in Still disease literature, then adds practical MAS danger checks and a severity interpretation for RheumaScore-style publication.

## Clinical problem

AOSD activity is often described narratively even when the patient has multiple simultaneously active systemic features. A reproducible score helps with:
- baseline severity description
- follow-up comparison
- early recognition of high-risk systemic phenotypes
- flagging patients who may need urgent MAS-focused evaluation

## What it outputs

- 12-item systemic score (0-12)
- activity band: low, moderate, high, very high
- severe-evolution warning when baseline burden is high
- MAS alert level using ferritin, fibrinogen, platelets, AST/ALT, and triglycerides when available
- treatment-intensity suggestion aligned with contemporary Still disease guidance

## Scored systemic items

One point each when present:
- fever
- evanescent rash
- pleuritis
- pneumonia / pulmonary infiltrates
- pericarditis
- hepatomegaly or abnormal liver tests
- splenomegaly
- lymphadenopathy
- leukocytosis >15,000/µL
- sore throat
- myalgia
- abdominal pain

## Run

```bash
python3 aosd_activity.py
```

## References

1. Gerfaud-Valentin M, Jamilloux Y, Iwaz J, Sève P. Adult-onset Still's disease. *Autoimmun Rev.* 2014;13(7):708-722. DOI: 10.1016/j.autrev.2014.01.058
2. Rau M, Schiller M, Krienke S, et al. Disease activity score for Still's disease. *Clin Rheumatol.* 2024. DOI: 10.1007/s10067-024-07127-8
3. Ruscitti P, Giacomelli R, Shoenfeld Y. A comprehensive review on adult onset Still's disease. *J Autoimmun.* 2018;93:24-36. DOI: 10.1016/j.jaut.2018.07.018
4. Ruscitti P, Cipriani P, Masedu F, et al. Adult-onset Still's disease: evaluation of prognostic tools and validation of the systemic score by analysis of 100 cases from three centers. *BMC Med.* 2016;14:194. DOI: 10.1186/s12916-016-0738-8
5. Colafrancesco S, Carubbi F, Gremese E, et al. The systemic score may identify life-threatening evolution in Still's disease. *Arthritis Rheumatol.* 2024. DOI: 10.1002/art.42845

## Limitations

- This is transparent clinical decision support, not a validated diagnostic substitute.
- The historic systemic score is feature-based and does not fully capture articular burden or patient-reported disease impact.
- MAS warning logic is heuristic and meant to prompt escalation, not replace HLH/MAS adjudication.
- AOSD remains a diagnosis of exclusion; infection, malignancy, and mimics still require clinician review.


## Executable Python code

```python
#!/usr/bin/env python3
"""
AOSD-ACTIVITY: Adult-Onset Still Disease systemic activity scoring.

Computes a transparent 12-item systemic score, interprets severity,
and adds pragmatic macrophage activation syndrome (MAS) warning logic.

References
- Gerfaud-Valentin M et al. Autoimmun Rev. 2014;13(7):708-722. DOI:10.1016/j.autrev.2014.01.058
- Ruscitti P et al. BMC Med. 2016;14:194. DOI:10.1186/s12916-016-0738-8
- Ruscitti P et al. J Autoimmun. 2018;93:24-36. DOI:10.1016/j.jaut.2018.07.018
- Colafrancesco S et al. Arthritis Rheumatol. 2024. DOI:10.1002/art.42845
- Rau M et al. Clin Rheumatol. 2024. DOI:10.1007/s10067-024-07127-8
"""

from __future__ import annotations

from dataclasses import dataclass, field
from typing import Dict, List, Optional
import json


SYSTEMIC_ITEMS = [
    ("fever", "Fever"),
    ("rash", "Evanescent rash"),
    ("pleuritis", "Pleuritis"),
    ("pneumonia", "Pneumonia/pulmonary infiltrates"),
    ("pericarditis", "Pericarditis"),
    ("liver_involvement", "Hepatomegaly or abnormal liver tests"),
    ("splenomegaly", "Splenomegaly"),
    ("lymphadenopathy", "Lymphadenopathy"),
    ("leukocytosis_gt_15000", "Leukocytosis >15,000/µL"),
    ("sore_throat", "Sore throat"),
    ("myalgia", "Myalgia"),
    ("abdominal_pain", "Abdominal pain"),
]


@dataclass
class AOSDPatient:
    name: str
    fever: bool = False
    rash: bool = False
    pleuritis: bool = False
    pneumonia: bool = False
    pericarditis: bool = False
    liver_involvement: bool = False
    splenomegaly: bool = False
    lymphadenopathy: bool = False
    leukocytosis_gt_15000: bool = False
    sore_throat: bool = False
    myalgia: bool = False
    abdominal_pain: bool = False
    ferritin_ng_ml: Optional[float] = None
    fibrinogen_mg_dl: Optional[float] = None
    platelets_k_ul: Optional[float] = None
    ast_u_l: Optional[float] = None
    alt_u_l: Optional[float] = None
    triglycerides_mg_dl: Optional[float] = None
    chronic_articular_pattern: bool = False
    notes: List[str] = field(default_factory=list)


@dataclass
class AOSDResult:
    patient: str
    systemic_score: int
    present_items: List[str]
    missing_items: List[str]
    activity_band: str
    severe_evolution_risk: str
    mas_alert: str
    treatment_intensity: str
    notes: List[str]


def compute_systemic_score(patient: AOSDPatient) -> Dict[str, List[str] | int]:
    present, missing = [], []
    score = 0
    for attr, label in SYSTEMIC_ITEMS:
        if getattr(patient, attr):
            score += 1
            present.append(label)
        else:
            missing.append(label)
    return {"score": score, "present": present, "missing": missing}


def classify_activity(score: int, chronic_articular_pattern: bool) -> str:
    if score <= 2:
        band = "LOW"
    elif score <= 4:
        band = "MODERATE"
    elif score <= 6:
        band = "HIGH"
    else:
        band = "VERY HIGH"

    if chronic_articular_pattern and score <= 4:
        return f"{band} systemic burden with possible articular-dominant phenotype"
    return f"{band} systemic burden"


def severe_evolution_flag(score: int) -> str:
    if score >= 7:
        return "HIGH — baseline systemic burden associated with higher risk of life-threatening evolution"
    if score >= 5:
        return "INTERMEDIATE — close follow-up warranted"
    return "LOW"


def mas_alert(patient: AOSDPatient) -> str:
    warning_points = 0

    if patient.ferritin_ng_ml is not None:
        if patient.ferritin_ng_ml >= 10000:
            warning_points += 3
        elif patient.ferritin_ng_ml >= 3000:
            warning_points += 2
        elif patient.ferritin_ng_ml >= 1000:
            warning_points += 1

    if patient.fibrinogen_mg_dl is not None and patient.fibrinogen_mg_dl < 250:
        warning_points += 2
    if patient.platelets_k_ul is not None and patient.platelets_k_ul < 150:
        warning_points += 1
    if patient.platelets_k_ul is not None and patient.platelets_k_ul < 100:
        warning_points += 1
    if patient.triglycerides_mg_dl is not None and patient.triglycerides_mg_dl >= 265:
        warning_points += 1

    liver_max = max(v for v in [patient.ast_u_l, patient.alt_u_l] if v is not None) if any(v is not None for v in [patient.ast_u_l, patient.alt_u_l]) else None
    if liver_max is not None and liver_max >= 150:
        warning_points += 1

    if warning_points >= 5:
        return "CRITICAL — MAS/HLH strongly consider urgent escalation and daily labs"
    if warning_points >= 3:
        return "HIGH — MAS warning pattern present"
    if warning_points >= 1:
        return "WATCH — partial MAS warning features"
    return "LOW"


def treatment_intensity(score: int, patient: AOSDPatient, mas_level: str) -> str:
    if mas_level.startswith("CRITICAL"):
        return "ICU-level/urgent inpatient reassessment, pulse glucocorticoids, high-dose anakinra-focused MAS pathway"
    if score >= 7:
        return "High-intensity systemic control: glucocorticoids plus early IL-1/IL-6-targeted therapy consideration"
    if score >= 5:
        return "Systemic phenotype likely active: glucocorticoids and early steroid-sparing biologic strategy"
    if patient.chronic_articular_pattern:
        return "Lower systemic burden but chronic articular pattern may justify MTX or IL-6-oriented strategy"
    return "Mild systemic burden: reassess trajectory, exclude mimics, tailor anti-inflammatory therapy"


def assess(patient: AOSDPatient) -> AOSDResult:
    systemic = compute_systemic_score(patient)
    score = systemic["score"]
    activity = classify_activity(score, patient.chronic_articular_pattern)
    severe = severe_evolution_flag(score)
    mas = mas_alert(patient)
    intensity = treatment_intensity(score, patient, mas)

    notes = list(patient.notes)
    if patient.ferritin_ng_ml is not None and patient.ferritin_ng_ml >= 10000:
        notes.append("Ferritin >10,000 ng/mL is a red flag for MAS/HLH in the right context.")
    if patient.fibrinogen_mg_dl is not None and patient.fibrinogen_mg_dl < 250:
        notes.append("Low fibrinogen in active Still disease is concerning because uncomplicated AOSD often has high fibrinogen.")
    if patient.chronic_articular_pattern:
        notes.append("Systemic score can underestimate burden in articular-dominant Still disease.")
    if score == 0:
        notes.append("A zero systemic score does not exclude controlled articular disease or treated disease.")

    return AOSDResult(
        patient=patient.name,
        systemic_score=score,
        present_items=systemic["present"],
        missing_items=systemic["missing"],
        activity_band=activity,
        severe_evolution_risk=severe,
        mas_alert=mas,
        treatment_intensity=intensity,
        notes=notes,
    )


def as_dict(result: AOSDResult) -> Dict[str, object]:
    return {
        "patient": result.patient,
        "systemic_score": result.systemic_score,
        "present_items": result.present_items,
        "missing_items": result.missing_items,
        "activity_band": result.activity_band,
        "severe_evolution_risk": result.severe_evolution_risk,
        "mas_alert": result.mas_alert,
        "treatment_intensity": result.treatment_intensity,
        "notes": result.notes,
    }


def print_result(result: AOSDResult) -> None:
    print("=" * 72)
    print(f"AOSD-ACTIVITY :: {result.patient}")
    print("=" * 72)
    print(f"Systemic score: {result.systemic_score}/12")
    print(f"Activity band: {result.activity_band}")
    print(f"Severe evolution risk: {result.severe_evolution_risk}")
    print(f"MAS alert: {result.mas_alert}")
    print(f"Treatment intensity: {result.treatment_intensity}")
    print("Present items:")
    for item in result.present_items:
        print(f"  - {item}")
    if result.notes:
        print("Notes:")
        for note in result.notes:
            print(f"  - {note}")
    print()


def demo() -> List[AOSDResult]:
    cases = [
        AOSDPatient(
            name="Case 1 — early systemic flare",
            fever=True,
            rash=True,
            sore_throat=True,
            leukocytosis_gt_15000=True,
            myalgia=True,
            liver_involvement=True,
            ferritin_ng_ml=4200,
            fibrinogen_mg_dl=540,
            platelets_k_ul=410,
            ast_u_l=96,
            alt_u_l=110,
        ),
        AOSDPatient(
            name="Case 2 — severe multisystem disease",
            fever=True,
            rash=True,
            pleuritis=True,
            pneumonia=True,
            pericarditis=True,
            liver_involvement=True,
            splenomegaly=True,
            lymphadenopathy=True,
            leukocytosis_gt_15000=True,
            sore_throat=True,
            myalgia=True,
            abdominal_pain=True,
            ferritin_ng_ml=18500,
            fibrinogen_mg_dl=210,
            platelets_k_ul=92,
            ast_u_l=240,
            alt_u_l=190,
            triglycerides_mg_dl=320,
        ),
        AOSDPatient(
            name="Case 3 — chronic articular phenotype with low systemic burden",
            fever=False,
            rash=False,
            sore_throat=False,
            liver_involvement=False,
            leukocytosis_gt_15000=False,
            chronic_articular_pattern=True,
            ferritin_ng_ml=780,
            fibrinogen_mg_dl=410,
            platelets_k_ul=280,
            notes=["Persistent inflammatory polyarthritis despite low current systemic feature load."],
        ),
    ]
    results = [assess(case) for case in cases]
    for result in results:
        print_result(result)
    print("JSON summary:")
    print(json.dumps([as_dict(r) for r in results], indent=2, ensure_ascii=False))
    return results


if __name__ == "__main__":
    demo()

```

## Demo output

```text
is
  - Hepatomegaly or abnormal liver tests
  - Splenomegaly
  - Lymphadenopathy
  - Leukocytosis >15,000/µL
  - Sore throat
  - Myalgia
  - Abdominal pain
Notes:
  - Ferritin >10,000 ng/mL is a red flag for MAS/HLH in the right context.
  - Low fibrinogen in active Still disease is concerning because uncomplicated AOSD often has high fibrinogen.

========================================================================
AOSD-ACTIVITY :: Case 3 — chronic articular phenotype with low systemic burden
========================================================================
Systemic score: 0/12
Activity band: LOW systemic burden with possible articular-dominant phenotype
Severe evolution risk: LOW
MAS alert: LOW
Treatment intensity: Lower systemic burden but chronic articular pattern may justify MTX or IL-6-oriented strategy
Present items:
Notes:
  - Persistent inflammatory polyarthritis despite low current systemic feature load.
  - Systemic score can underestimate burden in articular-dominant Still disease.
  - A zero systemic score does not exclude controlled articular disease or treated disease.

JSON summary:
[
  {
    "patient": "Case 1 — early systemic flare",
    "systemic_score": 6,
    "present_items": [
      "Fever",
      "Evanescent rash",
      "Hepatomegaly or abnormal liver tests",
      "Leukocytosis >15,000/µL",
      "Sore throat",
      "Myalgia"
    ],
    "missing_items": [
      "Pleuritis",
      "Pneumonia/pulmonary infiltrates",
      "Pericarditis",
      "Splenomegaly",
      "Lymphadenopathy",
      "Abdominal pain"
    ],
    "activity_band": "HIGH systemic burden",
    "severe_evolution_risk": "INTERMEDIATE — close follow-up warranted",
    "mas_alert": "WATCH — partial MAS warning features",
    "treatment_intensity": "Systemic phenotype likely active: glucocorticoids and early steroid-sparing biologic strategy",
    "notes": []
  },
  {
    "patient": "Case 2 — severe multisystem disease",
    "systemic_score": 12,
    "present_items": [
      "Fever",
      "Evanescent rash",
      "Pleuritis",
      "Pneumonia/pulmonary infiltrates",
      "Pericarditis",
      "Hepatomegaly or abnormal liver tests",
      "Splenomegaly",
      "Lymphadenopathy",
      "Leukocytosis >15,000/µL",
      "Sore throat",
      "Myalgia",
      "Abdominal pain"
    ],
    "missing_items": [],
    "activity_band": "VERY HIGH systemic burden",
    "severe_evolution_risk": "HIGH — baseline systemic burden associated with higher risk of life-threatening evolution",
    "mas_alert": "CRITICAL — MAS/HLH strongly consider urgent escalation and daily labs",
    "treatment_intensity": "ICU-level/urgent inpatient reassessment, pulse glucocorticoids, high-dose anakinra-focused MAS pathway",
    "notes": [
      "Ferritin >10,000 ng/mL is a red flag for MAS/HLH in the right context.",
      "Low fibrinogen in active Still disease is concerning because uncomplicated AOSD often has high fibrinogen."
    ]
  },
  {
    "patient": "Case 3 — chronic articular phenotype with low systemic burden",
    "systemic_score": 0,
    "present_items": [],
    "missing_items": [
      "Fever",
      "Evanescent rash",
      "Pleuritis",
      "Pneumonia/pulmonary infiltrates",
      "Pericarditis",
      "Hepatomegaly or abnormal liver tests",
      "Splenomegaly",
      "Lymphadenopathy",
      "Leukocytosis >15,000/µL",
      "Sore throat",
      "Myalgia",
      "Abdominal pain"
    ],
    "activity_band": "LOW systemic burden with possible articular-dominant phenotype",
    "severe_evolution_risk": "LOW",
    "mas_alert": "LOW",
    "treatment_intensity": "Lower systemic burden but chronic articular pattern may justify MTX or IL-6-oriented strategy",
    "notes": [
      "Persistent inflammatory polyarthritis despite low current systemic feature load.",
      "Systemic score can underestimate burden in articular-dominant Still disease.",
      "A zero systemic score does not exclude controlled articular disease or treated disease."
    ]
  }
]

```