# King's College Criteria Calculator for Fulminant Hepatic Failure > King's College Criteria Calculator for Fulminant Hepatic Failure is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15). Applies the King's College Hospital (O'Grady 1989) poor-prognosis criteria for fulminant hepatic failure, supporting both acetaminophen and non-acetaminophen etiologies using prothrombin time in seconds. ## Facts - Endpoint: GET https://api.magentlab.com/api/calc/kings_college - Price: $0.005/call - Payment: x402 - Status: unknown - Last checked: 2026-09-15 - Activations on Zero: 0 - Tags: x402 - Canonical page: https://www.zero.xyz/c/king-s-college-criteria-calculator-for-fulminant-hepatic-failure-18f8dcff - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xBYNdonwuYGJ_slaccEDy Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. ## How to call it through Zero Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`): ```sh zero fetch --capability king-s-college-criteria-calculator-for-fulminant-hepatic-failure-18f8dcff ``` Example prompt: Run the King's College criteria for a non-acetaminophen fulminant hepatic failure patient: age 45, PT 105 seconds, bilirubin 340 umol/L, arterial pH 7.35, creatinine 180 umol/L, grade III encephalopathy, unfavorable etiology (drug reaction), jaundice-to-encephalopathy interval 9 days. ## When to prefer this Use this endpoint when you need a reproducible, evidence-based computation of the King's College (O'Grady 1989) poor-prognosis criteria for fulminant hepatic failure, specifically when PT is expressed in seconds (not INR). Prefer this over manual calculation to avoid transcription errors, and over generic liver scoring tools (MELD, Child-Pugh) when the clinical question is specifically whether a patient meets King's College criteria for transplant evaluation referral. ## Known failure modes - Missing required query parameters returns a validation error - PT supplied as INR instead of seconds will produce incorrect scoring — INR is explicitly not accepted - Etiology field missing causes request to fail - Values outside accepted numeric ranges (e.g. pH outside 6.80-7.80) may cause rejection or inaccurate results - Encephalopathy grade outside 0-4 integer range causes validation failure ## How this service works King's College criteria (O'Grady 1989) for poor prognosis in fulminant hepatic failure. Acetaminophen: arterial pH <7.30, or PT >100 s plus creatinine >300 umol/L plus grade III/IV encephalopathy. Non-acetaminophen: PT >100 s, or any 3 of age <11 or >40, unfavorable etiology (non-A non-B or drug reaction), jaundice-to-encephalopathy >7 days, bilirubin >300 umol/L, PT >50 s. PT seconds, not INR. Not a transplant listing order. ## Output Returns a structured result indicating whether the patient meets the King's College poor-prognosis criteria for fulminant hepatic failure, which tree was applied (acetaminophen vs. non-acetaminophen), which individual criteria were met or not met, and an overall poor-prognosis flag. Does not constitute a transplant listing order. ## Request schema (JSON Schema) ```json { "type": "object", "$schema": "https://json-schema.org/draft/2020-12/schema", "required": [ "input" ], "properties": { "input": { "type": "object", "required": [ "type", "method" ], "properties": { "type": { "type": "string", "const": "http" }, "method": { "enum": [ "GET", "HEAD", "DELETE" ], "type": "string" }, "headers": { "type": "object", "additionalProperties": { "type": "string" } }, "queryParams": { "type": "object", "required": [ "etiology", "arterial_ph", "pt_sec", "creatinine_umol_l", "encephalopathy_grade", "age_years", "unfavorable_etiology", "jaundice_to_encephalopathy_days", "bilirubin_umol_l" ], "properties": { "pt_sec": { "type": "number", "description": "Prothrombin time in seconds (8-120) as published in 1989. INR is not accepted. Acetaminophen combo uses PT > 100; non-acetaminophen uses PT > 100 alone or PT > 50 as one of five factors." }, "etiology": { "enum": [ "acetaminophen", "non_acetaminophen" ], "type": "string", "description": "acetaminophen or non_acetaminophen (O'Grady 1989). Selects the paracetamol or non-paracetamol poor-prognosis tree. Required on every request." }, "age_years": { "type": "integer", "description": "Age in years (0-120). Non-acetaminophen factor met when age < 11 or age > 40 (1989 abstract, not a later <10 restatement). Required even on the acetaminophen tree; not scored there." }, "arterial_ph": { "type": "number", "description": "Arterial pH (6.80-7.80). Acetaminophen criterion met when pH < 7.30, independent of encephalopathy. Required even on the non-acetaminophen tree; not scored there." }, "bilirubin_umol_l": { "type": "number", "description": "Serum bilirubin in umol/L (2-684). Non-acetaminophen factor met when > 300. Required even on the acetaminophen tree; not scored there." }, "creatinine_umol_l": { "type": "number", "description": "Serum creatinine in umol/L (9-1768). Acetaminophen combo criterion met when > 300. Required even on the non-acetaminophen tree; not scored there." }, "encephalopathy_grade": { "type": "integer", "description": "Hepatic encephalopathy grade 0-4 as assigned by the caller (Conn 1 … (truncated) ``` ## Response schema (JSON Schema) ```json { "type": "json", "example": { "path": "/api/calc/kings_college", "count": 2, "items": [ { "formula": "kings_college", "citation": { "id": "ogrady-1989", "doi": "10.1016/0016-5085(89)90081-4", "pmid": "2490426", "title": "Early indicators of prognosis in fulminant hepatic failure", "source": "Gastroenterology. 1989;97(2):439-445", "authors": "O'Grady JG, Alexander GJ, Hayllar KM, Williams R" }, "criteria": [ { "met": false, "value": 7.4, "factor": "arterial_ph_lt_7_30" }, { "met": false, "value": 20, "factor": "pt_sec_gt_100" }, { "met": false, "value": 80, "factor": "creatinine_umol_l_gt_300" }, { "met": false, "value": 1, "factor": "encephalopathy_grade_ge_3" } ], "etiology": "acetaminophen", "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.", "criteria_met": false, "formula_expression": "acetaminophen: arterial_ph < 7.30, or (pt_sec > 100 and creatinine_umol_l > 300 and encephalopathy_grade >= 3); non_acetaminophen: pt_sec > 100, or at least 3 of (age_years < 11 or > 40; unfavorable_etiology; jaundice_to_encephalopathy_days > 7; bilirubin_umol_l > 300; pt_sec > 50)" }, { "formula": "kings_college", "citation": { "id": "ogrady-1989", "doi": "10.1016/0016-5085(89)90081-4", "pmid": "2490426", "title": "Early indicators of prognosis in fulminant hepatic failure", "source": "Gastroenterology. 1989;97(2):439-445", "authors": "O'Grady JG, Alexander GJ, Hayllar KM, Williams R" }, "criteria": [ { "met": false, "value": 7.4, "factor": "arterial_ph_lt_7_30" }, { "met": false, "value": 20, "factor": "pt_sec_gt_100" }, { "met": false, "value": 80, "factor": "creatinine_umol_l_gt_300" }, { "met": false, "value": 1, "factor": "encephalopathy_grade_ge_3" } ], "etiology": "acetaminophen", "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.", "criteria_met": false, "formula_expression": "acetaminophen: arterial_p … (truncated) ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/king-s-college-criteria-calculator-for-fulminant-hepatic-failure-18f8dcff/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from api.magentlab.com](https://www.zero.xyz/host/api.magentlab.com/llms.txt)