Ppgl Asymptomatic Carrier Surveillance Age

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name: ppgl-asymptomatic-carrier-surveillance-age
description: Determines the appropriate age to initiate surveillance for asymptomatic genetic carriers of PPGL pathogenic variants. Indicated for a child of a PPGL patient with a known pathogenic variant, identification of an at‑risk relative for PPGL genetic screening, or initiation of surveillance in a pediatric genetic carrier.
---

# Asymptomatic Genetic Carrier Surveillance Initiation Age for PPGL

## STEP 1 — Gather Information
Collect the specific pathogenic variant (SDHB vs SDHA/SDHC/SDHD) from genetic testing and confirm the indication (child of PPGL patient with known variant, at‑risk relative, or pediatric carrier).

## STEP 2 — Rule In / Rule Out
Determine if the carrier harbors an SDHB pathogenic variant; if yes, proceed to SDHB pathway, otherwise proceed to SDHA/SDHC/SDHD pathway.

## STEP 3 — Classify or Stratify
Assign the surveillance initiation age range: 6–10 years for SDHB carriers; 10–15 years for SDHA, SDHC, or SDHD carriers.

## STEP 4 — Decide
Begin surveillance at the assigned age with annual clinical evaluation, urinary or plasma‑free fractionated metanephrines, and MRI of the head, neck, chest, abdomen, and pelvis; repeat per schedule (annual clinical, biennial biochemical, MRI every 2–3 years).

## Clinical Guardrails / Mimics / Pitfalls
Do not start surveillance before age 6 for any variant; avoid CT in children due to radiation exposure; do not rely solely on biochemical testing without imaging; do not delay surveillance beyond age 15 for SDHA/SDHC/SDHD carriers; ensure genetic counseling is provided to discuss penetrance and variable expression.

## Concrete Clinical Example
A 7‑year‑old child of a parent with an SDHB‑related PPGL tests positive for the familial SDHB variant; surveillance is initiated with yearly clinical exam, urinary fractionated metanephrines, and whole‑body MRI.

**Source:** Japan Endocrine Society Clinical Practice Guideline for the Diagnosis and Management of Pheochromocytoma and Paraganglioma 2025, Japan Endocrine Society, 2025, doi:10.1507/endocrj.EJ25-0165

> **TODO:** consider adding scripts/calc.py for the ppgl-asymptomatic-carrier-surveillance-age calculator