Faltering growth in a 15-month-old after early weaning
Amal is a 15-month-old girl brought to the outpatient clinic by her aunt. Her birth weight was 3.1 kg. At 12 months she weighed 9.0 kg; today she weighs 8.1 kg, measures 76 cm (74 cm at 12 months), and has a head circumference of 46 cm. She was exclusively breastfed until 6 months, then received diluted formula and rice water. The family has moved twice, and her mother has untreated depression. Amal now drinks about 900 mL of cow's milk daily, refuses spoon feeds, and eats dirt. She has no fever, diarrhea, or vomiting. She walks and says three words. She is alert but thin, with mild pallor and no edema or organomegaly. Her vaccinations are up to date.
1. Describe the growth pattern and give your prioritized differential. Which features make an organic cause less likely, and which features still require you to exclude one?
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Growth pattern. Her weight has crossed downward through at least two major weight centiles, and she has lost about 10% of body weight in 3 months. Length and head circumference remain near the median. That dissociation is the key: in acute undernutrition weight falls first, whereas length and head circumference are relatively spared until malnutrition is prolonged. This is weight faltering, not a primary endocrine short stature.
Prioritized differential. (1) Feeding-practice undernutrition: 900 mL/day of cow's milk is energy-dilute, displaces solids, and causes iron deficiency; diluted formula and rice water add little. (2) Iron deficiency with pica and pallor. (3) Celiac disease, which can present with isolated faltering growth and no diarrhea. (4) Chronic infection: tuberculosis is common in Iraq; also giardiasis and HIV. (5) Renal tubular acidosis or chronic kidney disease. (6) Lead poisoning from pica. (7) Maternal depression and psychosocial neglect.
Features arguing against organic disease include normal development, no organomegaly, no fever, and a clear dietary explanation. Features that still demand exclusion are weight loss rather than plateau, pica, maternal depression, and the local prevalence of TB and celiac disease. Do not label it non-organic until screening is complete.
2. List the first-line investigations you would order and justify each. Which tests would you avoid, and why?
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Order tests that change management:
- CBC, blood film, ferritin, and CRP: iron deficiency is likely; ferritin is an acute-phase reactant, so interpret it with CRP.
- Celiac serology: tissue transglutaminase IgA plus total IgA, because IgA deficiency causes false-negative results.
- Electrolytes, urea, creatinine, and venous blood gas: look for renal tubular acidosis and chronic kidney disease.
- Urine dipstick, microscopy, and culture: proteinuria, glycosuria, and infection.
- Stool microscopy for Giardia and occult blood: chronic parasitosis and intestinal inflammation.
- HIV antibody and TB screening: chest radiograph plus IGRA or tuberculin test according to local protocol.
- Blood lead level: pica makes lead exposure plausible.
TSH and bone age are not first-line: hypothyroidism and growth hormone deficiency rarely present with isolated weight faltering and a normal head circumference.
Avoid food-specific IgG panels, hair mineral analysis, and broad allergy screens. They generate false positives, lead to unnecessary elimination diets, and do not change management. Also avoid starting iron before taking blood samples, because it confounds the ferritin result.
3. Set out a 3-month management plan, including nutritional rehabilitation, family intervention, and safety-netting.
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Management has three tracks.
- Nutrition. Dietitian review; three meals and two snacks daily; energy-dense local foods such as oil, tahini, egg, and legumes. Reduce cow's milk to 400-500 mL/day so solids are accepted; stop diluted formula. Start oral iron 3-6 mg/kg/day elemental after samples are taken. Aim for catch-up growth of 5-10 g/kg/day, which is faster than usual weight gain.
- Family. Treat maternal depression through adult services; involve a social worker; ask directly about food insecurity, housing, and who feeds the child. Give written feeding advice in the family's language.
- Monitoring and safety. Weigh every 2 weeks on the same scale; measure length and head circumference monthly. Repeat hemoglobin at 4-6 weeks. If weight is still falling at 4 weeks, or if new symptoms appear, escalate to pediatric gastroenterology and consider admission. Admit immediately for severe dehydration, infection, or a safeguarding concern.
Do not promise rapid catch-up without reviewing the family's capacity. Faltering growth is a symptom, and the cause must be treated.