Health
Reticulocyte Production Index (RPI) Calculator
Calculate the Reticulocyte Production Index (RPI) to judge whether the marrow is responding appropriately to anemia. Step 1 — corrected reticulocyte count CRC = Retic% × (patient Hct / normal Hct) (normal Hct 45% men, 40% women). Step 2 — maturation (shift) factor (days) varies with Hct: 45%→1.0, 35%→1.5, 25%→2.0, 15%→2.5 (linearly interpolated). Step 3 — RPI = CRC / maturation factor. Interpretation: RPI > 2 (especially ≥ 3) → appropriate marrow response, suggesting hemolysis or recovery from acute blood loss (the marrow is working — look for peripheral loss/destruction); RPI < 2 → hypoproliferative anemia (iron deficiency, anemia of chronic disease/inflammation, aplastic anemia, renal anemia, MDS, marrow infiltration, untreated megaloblastic anemia). RPI is less reliable when anemia is changing rapidly; if an absolute reticulocyte count (ARC, ×10⁹/L) is available, prefer it. Based on Hillman & Finch, Berlin Blood 1959, and MDCalc. Not medical advice.
Quick start
Call this tool from your code in three languages.
curl -X POST 'https://api.elysiatools.com/en/api/tools/reticulocyte-production-index' \
-H 'Content-Type: application/json' \
-d '{"reticPercent":10,"hct":22,"normalHctPreset":"male","normalHctCustom":0,"decimalPlaces":2}'API reference
Send a POST request with your inputs as JSON. File parameters require a separate upload first.
Endpoint
POST https://api.elysiatools.com/en/api/tools/reticulocyte-production-indexParameters
| Name | Type | Required | Description |
|---|---|---|---|
| reticPercent | number | Yes | Reticulocyte percentage from the CBC differential (0–100). For example, enter 8 for 8%. |
| hct | number | Yes | Patient hematocrit in percent (e.g. 25 for 25%). |
| normalHctPreset | select | No | Choose the normal hematocrit reference used for the anemia correction. Male 45%, female 40%, or custom. |
| normalHctCustom | number | No | Custom normal hematocrit (%) — used only when 'Custom (%)' is selected above. |
| decimalPlaces |
MCP integration
Add this tool to your Model Context Protocol server so AI agents can list and call it.
Server configuration
Add this block to your MCP client configuration:
{
"mcpServers": {
"elysiatools-reticulocyte-production-index": {
"name": "reticulocyte-production-index",
"description": "Calculate the Reticulocyte Production Index (RPI) to judge whether the marrow is responding appropriately to anemia. Step 1 — corrected reticulocyte count CRC = Retic% × (patient Hct / normal Hct) (normal Hct 45% men, 40% women). Step 2 — maturation (shift) factor (days) varies with Hct: 45%→1.0, 35%→1.5, 25%→2.0, 15%→2.5 (linearly interpolated). Step 3 — RPI = CRC / maturation factor. Interpretation: RPI > 2 (especially ≥ 3) → appropriate marrow response, suggesting hemolysis or recovery from acute blood loss (the marrow is working — look for peripheral loss/destruction); RPI < 2 → hypoproliferative anemia (iron deficiency, anemia of chronic disease/inflammation, aplastic anemia, renal anemia, MDS, marrow infiltration, untreated megaloblastic anemia). RPI is less reliable when anemia is changing rapidly; if an absolute reticulocyte count (ARC, ×10⁹/L) is available, prefer it. Based on Hillman & Finch, Berlin Blood 1959, and MDCalc. Not medical advice.",
"baseUrl": "https://api.elysiatools.com/mcp/sse?toolId=reticulocyte-production-index",
"command": "",
"args": [],
"env": {},
"isActive": true,
"type": "sse"
}
}
}List available tools
After connecting to the SSE endpoint, list the exposed tools:
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/list"
}Call this tool
Invoke the tool by its id, passing arguments built from its parameters:
{
"jsonrpc": "2.0",
"id": 2,
"method": "tools/call",
"params": {
"name": "reticulocyte-production-index",
"arguments": {
"reticPercent": 10,
"hct": 22,
"normalHctPreset": "male",
"normalHctCustom": 0,
"decimalPlaces": 2
}
}
}