A patient maintained on home total parenteral nutrition for eight years develops unexplained hyperglycaemia requiring escalating insulin doses, along with peripheral neuropathy and encephalopathy. Plasma glucose monitoring excludes sepsis and the dextrose load has been unchanged. Deficiency of which trace element BEST explains this presentation?
- A Chromium ✓
- B Manganese
- C Selenium
- D Molybdenum
Correct answer: A. Chromium
Explanation
Chromium potentiates insulin action, and trivalent chromium deficiency in patients on long-term parenteral nutrition presents with refractory hyperglycaemia, peripheral neuropathy, and encephalopathy that improve with supplementation. Selenium deficiency causes dilated cardiomyopathy and myopathy, so option C does not fit. Manganese excess rather than deficiency produces a parkinsonian neurotoxicity syndrome in TPN patients, and molybdenum deficiency causes neurological dysfunction with high sulfite levels, neither matching the glucose intolerance.
Reference: Modern Nutrition in Health and Disease, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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