Routine fruit washing to prevent acute toxic encephalopathy – Authors' reply
Authors: Akshay C Dhariwal, Srinivas Venkatesh, Aakash Shrivastava, Amit Chakrabarti, Jerry D Thomas, Melissa D Carter, Rudolph Johnson, Kayla F Laserson, Padmini Srikantiah
Journal: The Lancet Global Health (2017)

P A Desingu points out our investigation finding that routinely washing vegetables and fruits could be protective against acute toxic encephalopathy1Shrivastava A Kumar A Thomas JD et al.Association of acute toxic encephalopathy with litchi consumption in an outbreak in Muzaffarpur, India, 2014: a case-control study.Lancet Glob Health. 2017; 5: e458-e466Summary Full Text Full Text PDF PubMed Scopus (61) Google Scholar and suggests that this indicates that an exogenous toxin or agent in unwashed fruits or vegetables, rather than the naturally occurring toxins hypoglycin A and methylenecyclopropylglycine (MCPG) found in lychees, might be associated with the recurring epidemic toxic encephalopathy in Muzaffarpur. We considered this possibility, and tested extensively for evidence of exogenous agents, such as pesticides and herbicides, in the biological specimens of affected children as well as in fruits, vegetables, and grains collected from affected villages; these results were all consistently negative.1Shrivastava A Kumar A Thomas JD et al.Association of acute toxic encephalopathy with litchi consumption in an outbreak in Muzaffarpur, India, 2014: a case-control study.Lancet Glob Health. 2017; 5: e458-e466Summary Full Text Full Text PDF PubMed Scopus (61) Google Scholar Additionally, an exogenous toxin that can be eliminated by washing a fruit or vegetable would probably be associated with rapid onset of symptoms shortly after exposure, such as that seen with a typical organophosphate or carbamate pesticide.2King AM Aaron CK Organophosphate and carbamate poisoning.Emerg Med Clin North Am. 2015; 33: 133-151Summary Full Text Full Text PDF PubMed Scopus (154) Google Scholar By contrast, children affected with the toxic encephalopathy in Muzaffarpur overwhelmingly presented in the early morning (0400–0800) with profound hypoglycaemia and seizures, hours after any potential exposure to a toxic agent. This observed clinical presentation is more consistent with the impaired glucose and fatty acid metabolism that results from hypoglycin A or MCPG toxicity. Furthermore, a toxin associated with this illness would also have to explain the profound derangement in urinary amino acids observed in affected children; this rarely observed metabolic abnormality suggests a mitochondrial toxin as would be expected with hypoglycin A and MCPG, and is not known to be associated with any exogenous substance or pesticide. This pattern of metabolic derangement is what has been reported and accepted as evidence of hypoglycin A toxicity from ackee fruit poisoning, even without direct evidence of hypoglycin A toxicity.3Joskow R Belson M Vesper H Backer L Rubin C Ackee fruit poisoning: an outbreak investigation in Haiti 2000-2001, and review of the literature.Clin Toxicol. 2006; 44: 267-273Crossref PubMed Scopus (57) Google Scholar, 4Meda HA Diallo B Buchet JP et al.Epidemic of fatal encephalopathy in preschool children in Burkina Faso and consumption of unripe ackee (Blighia sapida) fruit.Lancet. 1999; 353: 536-540Summary Full Text Full Text PDF PubMed Scopus (44) Google Scholar Our investigation further showed the presence of metabolites of hypoglycin A in the urine of affected children.1Shrivastava A Kumar A Thomas JD et al.Association of acute toxic encephalopathy with litchi consumption in an outbreak in Muzaffarpur, India, 2014: a case-control study.Lancet Glob Health. 2017; 5: e458-e466Summary Full Text Full Text PDF PubMed Scopus (61) Google Scholar Based on these findings, and as we report in our Article,1Shrivastava A Kumar A Thomas JD et al.Association of acute toxic encephalopathy with litchi consumption in an outbreak in Muzaffarpur, India, 2014: a case-control study.Lancet Glob Health. 2017; 5: e458-e466Summary Full Text Full Text PDF PubMed Scopus (61) Google Scholar the absence of clinical, epidemiological, or laboratory findings to support causes of illness related to infectious pathogens, pesticides, or heavy metals suggest the observed protective association of routinely washing fruit or vegetables was not directly related to an exogenous toxin or infectious agent. We declare no competing interests. The findings and conclusions in this Correspondence are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention. Association of acute toxic encephalopathy with litchi consumption in an outbreak in Muzaffarpur, India, 2014: a case-control studyOur investigation suggests an outbreak of acute encephalopathy in Muzaffarpur associated with both hypoglycin A and MCPG toxicity. To prevent illness and reduce mortality in the region, we recommended minimising litchi consumption, ensuring receipt of an evening meal and implementing rapid glucose correction for suspected illness. A comprehensive investigative approach in Muzaffarpur led to timely public health recommendations, underscoring the importance of using systematic methods in other unexplained illness outbreaks. Full-Text PDF Open AccessRoutine fruit washing to prevent acute toxic encephalopathyI read with great interest the Article by Aakash Shrivastava and colleagues (January, 2017)1 that reported the association of a 2014 outbreak of acute toxic encephalopathy in Muzaffarpur, India, with lychee (also spelled litchi) consumption using a case-control study. The study reported that lychee consumption 24 h before onset of symptoms was associated with acute toxic encephalopathy in 67 (65%) of 103 cases and 23 (23%) of 102 controls. The same case-control study reported that routinely washing vegetables and fruits was associated with acute toxic encephalopathy in 32 (32%) of 99 cases and 58 (70%) of 83 controls. Full-Text PDF Open Access