A 7-month-old infant fed predominantly on goat's milk since 2 months of age presents with pallor and mild hepatosplenomegaly but NO neurological abnormalities. CBC shows Hb 6.9 g/dL, MCV 108 fL, hypersegmented neutrophils, and elevated LDH. Which of the following best explains the absence of neurologic findings compared with a typical case of infantile tremor syndrome?

• A Folate deficiency causes megaloblastic anemia without subacute combined degeneration ✓
• B Goat's milk contains adequate cobalamin but lacks intrinsic factor
• C The neurologic damage in infancy is always irreversible regardless of cause
• D Neurologic involvement requires concurrent iron deficiency

Explanation

Goat's milk is notoriously poor in folate, producing megaloblastic anemia identical hematologically to A12 deficiency but WITHOUT the posterior column and corticospinal tract damage seen in A12 deficiency, because folate does not participate in myelin methylmalonate metabolism. This preserves normal neurology. Goat's milk is also low in A12, but the classical teaching point tested here is isolated folate lack sparing the nervous system.

Reference: Ghai Essential Pediatrics, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.