Marasmus — DTM&H MCQ

Correct answer: E — Marasmus

Marasmus (E) is the correct diagnosis. It is the non-oedematous form of severe acute malnutrition caused by prolonged, severe overall energy (calorie) deficiency, producing the classic clinical triad in the stem: marked wasting, visible ribs, and loss of subcutaneous fat, with a "wizened" appearance and no oedema. WHO criteria for severe wasting (very low weight-for-height or MUAC) with the explicit absence of bilateral pitting oedema define marasmus, distinguishing it from oedematous malnutrition syndromes. The clinical picture described, an infant with prolonged food shortage and pure wasting, is textbook marasmus rather than a micronutrient deficiency state. Why the other options are wrong: D. Rickets: caused by vitamin D or calcium deficiency, presenting with bony deformities such as bowed legs, widened wrist and costochondral junctions ('rickety rosary'), and delayed fontanelle closure, not generalised wasting. B. Beriberi: caused by thiamine deficiency, presenting with cardiac failure (wet beriberi) or peripheral neuropathy (dry beriberi), not the wasting syndrome described. A. Kwashiorkor: results predominantly from protein deficiency relative to energy intake and is defined by bilateral pitting oedema, often with hepatomegaly, skin and hair changes; the stem explicitly states there is no oedema, excluding this diagnosis. C. Pellagra: caused by niacin (vitamin B3) deficiency, classically causing dermatitis, diarrhoea and dementia, unrelated to the wasting phenotype here. Key point: the presence or absence of bilateral pitting oedema is the key discriminator between marasmus (no oedema) and kwashiorkor (oedema) in severe acute malnutrition.

Reference: World Health Organization, Guideline: Updates on the Management of Severe Acute Malnutrition in Infants and Children (2013), Section on clinical classification of severe wasting vs oedematous malnutrition, https://www.who.int/publications/i/item/9789241506328