P2B109: Relationship of Lactate and Thiamine Deficiency Among Children in Lao People's Democratic Republic

Background: Infantile beriberi is the most commonly fatal thiamine deficiency disorder, accounting for up to 34% of preventable infant deaths in Lao People’s Democratic Republic (Lao PDR). Previous reports have suggested that thiamine deficiency should be considered in ill children with refractory hyperlactatemia, but little is known about the relationship of lactate and clinical or biochemical thiamine deficiency.

Methods: This is a secondary analysis of data from the LaoThiamine study, a prospective cohort study enrolling children aged 21 days to 18 months who were hospitalized with at least one symptom suggestive of thiamine deficiency in a region of Lao PDR where thiamine deficiency is endemic. Data from 402 participants were analyzed with logistic regression and receiver operating characteristic curves to examine the relationship between baseline blood lactate and signs and symptoms of thiamine deficiency and clinical improvement following thiamine administration. Clinical improvement was defined as improvement in vital signs, symptoms, and clinical examination within 8-14 hours of thiamine administration. Hyperlactatemia was defined as lactate > 4 mmol/L. Thiamine deficiency was defined as whole blood thiamine diphosphate < 40 nmol/L.

Results: Among all enrolled children, baseline hyperlactatemia was associated with seven signs and symptoms of thiamine deficiency, including persistent crying, hoarseness, low oxygen saturation, noisy or nasal breathing, liver enlargement, abnormal eye movements, and convulsions (Table 1). A minority of symptoms were associated with hyperlactatemia only among children with biochemical thiamine deficiency, including, persistent crying, hoarseness, and liver enlargement. Features characteristic of infantile wet beriberi, including tachycardia and tachypnea, were not associated with baseline hyperlactatemia.

The odds of clinical improvement after thiamine administration were two times greater among children with baseline hyperlactatemia versus normal lactate levels [OR (95%CI) 2.32 (1.28, 4.45) p=0.0078]. Although clinical improvement following thiamine administration was not significantly associated with biochemical thiamine deficiency, baseline lactate level demonstrated utility as a predictor of biochemical thiamine deficiency [AUROC 0.76 (0.67, 0.84) p< 0.001].

Finally, hyperlactatemia amongst all enrolled children was associated with increased odds of mortality [3.84 (1.43, 9.88), p=0.0056].

Conclusion: Among children presenting with signs or symptoms of thiamine deficiency in an endemic area for thiamine deficiency, specific physical exam features are associated with hyperlactatemia. Hyperlactatemia is also associated with favorable response to thiamine administration, predictive of biochemical thiamine deficiency, and associated with increased odds of mortality. Lactate may be useful as a prognostic indicator among children with thiamine deficiency disorders.