A 9-month-old boy is brought to the office for evaluation of poor weight gain. His mother reports he has been irritable during feedings and often refuses to eat. Review of his growth chart shows serial measurements as follows: Age Weight Weight Percentile Length Length Percentile 2 months 5.8 kg 75th 58 cm 50th 4 months 6.9 kg 50th 63 cm 50th 6 months 7.2 kg 25th 66 cm 50th 9 months 7.5 kg 5th 69 cm 25th
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AWeight and length both declining proportionally from 50th to 25th percentile
BWeight remaining consistently between 5th and 10th percentile across all visits
CLength percentile declining from 50th to 25th while weight remains stable at 50th
DWeight increasing from 5.8 kg to 7.5 kg with proportional length increase
ECrossing two major percentile lines from 75th to 5th over 7 months
✓ Correct answer: E. Crossing two major percentile lines from 75th to 5th over 7 monthsConcerning growth pattern is crossing two major percentile lines (75th to 5th) over a short interval, indicating failure to thrive. Weight deceleration is disproportionate to length, suggesting inadequate caloric intake rather than genetic short stature. This requires comprehensive evaluation including feeding history, psychosocial assessment, and laboratory studies. Distractor1 describes normal proportional growth. Distractor2 represents constitutional growth variant. Distractor3 shows stable percentiles. Distractor4 misinterprets the data pattern.
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