Eso Pediatric Obesity Infant Diagnosis

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name: eso-pediatric-obesity-infant-diagnosis
description: Diagnoses obesity in infants and toddlers under 2 years of age when sex-specific weight-for-recumbent length is at or above the 97.7th percentile on WHO growth charts. Consider this assessment during well-child visits when caregivers report excessive weight gain, crossing of percentile channels, or when length and weight measurements suggest disproportionate adiposity.
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# Diagnose obesity in infants using weight-for-length percentile

## STEP 1 — Gather Information
Collect infant's sex, age, weight (kg), and recumbent length (cm). Ensure length is measured supine with infant fully extended. Plot these values on the WHO weight-for-length percentile chart corresponding to the infant's sex and exact age.

## STEP 2 — Rule In / Rule Out
Determine the weight-for-length percentile from the plotted point. If the percentile is ≥97.7th, rule in obesity; if the percentile is <97.7th, rule out obesity for this assessment.

## STEP 3 — Classify or Stratify
Classify the infant as obese when the weight-for-recumbent length is at or above the 97.7th percentile on the WHO chart. No further subcategorization is recommended for this age group per guideline.

## STEP 4 — Decide
For infants classified as obese, initiate preventive counseling on age-appropriate feeding practices (e.g., responsive feeding, avoidance of sugar-sweetened beverages), schedule weight-for-length monitoring every 1–2 months, and evaluate for underlying endocrine or genetic causes only if growth velocity is aberrant or comorbidities are suspected.

## Clinical Guardrails / Mimics / Pitfalls
Do not use CDC BMI charts for children <2 years; do not rely on weight-for-length after the second birthday; avoid mismeasuring recumbent length (must be supine, not standing); do not apply the ≥97.7th percentile threshold to preterm infants without adjusting for gestational age.

## Concrete Clinical Example
A 9‑month‑old male presents for well‑child visit; weight 10.5 kg, length 70 cm. Plotting on WHO boys’ weight‑for‑length chart shows the 98th percentile. Since this exceeds the 97.7th percentile, obesity is diagnosed, and feeding counseling is initiated.

**Source:** Pediatric Obesity Assessment, Treatment, and Prevention: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2017, DOI:10.1210/jc.2016-2573
> **TODO:** consider adding scripts/calc.py for the eso-pediatric-obesity-infant-diagnosis calculator