Thiamine Deficiency - Differential Diagnosis Framework and Clinical Manifestations Causes of Thiamine Deficiency: • Poor intake: - Diets high in polished rice/processed grains - Chronic alcoholism - TPN - Gastric bypass surgery • Poor absorption: - Malnutrition - Gastric bypass surgery - Malabsorption • Increased loss: - Diarrhea - Hyperemesis gravidarum - Diuretic use - Renal replacement therapy • Increased thiamine utilization: - Pregnancy - Lactation - Hyperthyroidism - Refeeding syndrome Sources of Thiamine: • Found in: Yeast, Legumes, Pork, Brown rice, Cereals • Low in: White/polished rice, Milled white cereals, Milk products Thiamine • Necessary For: - Oxidative phosphorylation - Myocardial energy production • Deficiency leads to increased pyruvate and lactate • Increased pyruvate & lactate decrease PVR and increase venous blood flow, increasing cardiac preload • Increased preload and myocardial dysfunction leads to congestive heart failure • Wet beri-beri triggers Right HF • Moderate pulmonary HTN is common • Hyperkinetic LVEF is also seen • Lactic acidosis may not demonstrate diminished pH due to compensatory hyperventilation Wernicke-Korsakoff Syndrome: • Wernicke's Encephalopathy - Acute neurological condition: - Nystagmus - Ophthalmoplegia - Ataxia/confusion - WE + memory loss & psychosis with confabulation is consistent with WKS • Korsakoff Syndrome - Chronic neurological condition: - Impaired short-term memory - Confabulation Beri Beri: • Dry Beri Beri: - Symmetrical peripheral neuropathy of the distal extremities - Sensory and motor impairments - Impaired reflexes - Burning pain in extremities - Muscle weakness - Falls due to peripheral neuropathy • Wet Beri Beri: - High output heart failure - Dilated cardiomyopathy - Tachycardia - High output congestive HF - Peripheral edema Additional Findings: • Acute renal failure: - Increased Lactate/Pyruvate - AV shunt, renal vascular contraction, blood flow reduction - Decreased GFR • Acute liver failure: Hepatic congestion due to RHF #Thiamine #Deficiency #Manifestations #Differential #Diagnosis #syndromes #beriberi #nutrition #pathophysiology #wernickes #korsakoff
