{"uid":"cap_u0OoQksov9JWPm1dgQmOf","slug":"saag-calculator-serum-ascites-albumin-gradient-6e73e3f9","name":"SAAG Calculator (Serum-Ascites Albumin Gradient)","description":"Runyon 1992 SAAG as serum albumin minus ascites albumin in g/dL, rounded to one decimal. portal_hypertension_physiology is true when SAAG >= 1.1 g/dL. Gradient only; not Light-style exudate/transudate criteria for ascites. Not a diagnosis. magent does not diagnose portal hypertension or peritonitis. Serum and ascites albumin as g/dL or g/L.","url":"https://api.magentlab.com/api/calc/saag","method":"GET","headers":{},"bodySchema":{"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":[],"properties":{"albumin_g_l":{"type":"number","description":"Serum albumin in g/L (10-60). Converted as g/dL = g/L / 10. Provide this or albumin_g_dl, not both."},"albumin_g_dl":{"type":"number","description":"Serum albumin in g/dL (1-6). Provide this or albumin_g_l, not both."},"ascites_albumin_g_l":{"type":"number","description":"Ascites albumin in g/L (1-60). Converted as g/dL = g/L / 10. Provide this or ascites_albumin_g_dl, not both."},"ascites_albumin_g_dl":{"type":"number","description":"Ascites albumin in g/dL (0.1-6). Provide this or ascites_albumin_g_l, not both. May be lower than serum albumin."}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"path":"/api/calc/saag","count":2,"items":[{"formula":"saag","citation":{"id":"runyon-1992","doi":"10.7326/0003-4819-117-3-215","title":"The serum-ascites albumin gradient is superior to the exudate-transudate concept in the differential diagnosis of ascites","source":"Ann Intern Med. 1992;117(3):215-220","authors":"Runyon BA, Montano AA, Akriviadis EA, Antillon MR, Irving MA, McHutchison JG"},"saag_g_dl":1.5,"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.","albumin_g_dl":3.5,"formula_expression":"saag_g_dl = albumin_g_dl - ascites_albumin_g_dl","ascites_albumin_g_dl":2,"portal_hypertension_physiology":true},{"formula":"saag","citation":{"id":"runyon-1992","doi":"10.7326/0003-4819-117-3-215","title":"The serum-ascites albumin gradient is superior to the exudate-transudate concept in the differential diagnosis of ascites","source":"Ann Intern Med. 1992;117(3):215-220","authors":"Runyon BA, Montano AA, Akriviadis EA, Antillon MR, Irving MA, McHutchison JG"},"saag_g_dl":1.5,"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.","albumin_g_dl":3.5,"formula_expression":"saag_g_dl = albumin_g_dl - ascites_albumin_g_dl","ascites_albumin_g_dl":2,"portal_hypertension_physiology":true}]}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_iXZsm9XRQDBCS2aKJ_5Co","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Calculates the Serum-Ascites Albumin Gradient (SAAG) using Runyon 1992 criteria and flags portal hypertension physiology when SAAG ≥ 1.1 g/dL","exampleAgentPrompt":"Calculate the SAAG for my patient whose serum albumin is 3.8 g/dL and ascites albumin is 1.4 g/dL — does the gradient suggest portal hypertension physiology?","exampleUseCases":[{"title":"Cirrhosis ascites workup","prompt":"My patient has new-onset ascites and a serum albumin of 3.2 g/dL with ascites albumin of 0.9 g/dL — calculate the SAAG and tell me whether this points to portal hypertension physiology."},{"title":"Malignant ascites differentiation","prompt":"Can you compute the serum-ascites albumin gradient for serum albumin 42 g/L and ascites albumin 18 g/L, and flag whether the result meets the portal hypertension threshold?"},{"title":"Hepatic failure monitoring","prompt":"Run a SAAG calculation for a cirrhotic patient with serum albumin 2.8 g/dL and ascites albumin 1.9 g/dL — I need to know if the gradient is above or below 1.1."}],"resultDescription":"Returns the calculated SAAG value in g/dL rounded to one decimal place and a boolean portal_hypertension_physiology flag (true when SAAG ≥ 1.1 g/dL). Does not diagnose portal hypertension, peritonitis, or classify by Light criteria.","failureModes":["Missing required albumin inputs — returns error if neither serum albumin field is provided","Both unit variants provided for the same parameter (e.g., albumin_g_dl and albumin_g_l simultaneously) — rejected as conflicting input","Values outside physiological range (e.g., serum albumin below 1 g/dL or above 6 g/dL) may return validation error","Ascites albumin exceeding serum albumin is physiologically unusual but accepted; gradient may be negative","Payment failure via x402 protocol returns 402 status before computation occurs"],"whenToPreferThis":"Use this endpoint when you need a fast, deterministic SAAG calculation per Runyon 1992 for portal hypertension physiology classification. Prefer it over generic lab calculators when you need explicit portal_hypertension_physiology boolean output. Note: this does NOT apply Light criteria (exudate/transudate) — use the sibling Light 1972 pleural fluid endpoint for pleural effusions. Best for hepatology, gastroenterology, or hospitalist workflows requiring ascites etiology triage.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T13:16:17.081Z","isFirstParty":false}