Accidental Ingestion of Naphthalene Induced Methemoglobinemia: A Rare Case Report

Abstract

Introduction:  Naphthalene poisoning is an uncommon type of toxicity and presents diagnostic and treatment difficulties owing to its complex clinical progression. It is readily absorbed through oral, dermal, and inhalation routes and is metabolized into reactive epoxides and quinone metabolites via cytochrome P450 oxidation. It is eliminated in urine as mercapturic acids, methylthio derivatives, and glucuronide conjugate. following liver metabolism, The most active derivative, alpha-naphthol, leads to hemolysis and the formation of Heinz bodies. Exposure frequently leads to headache, changed mental state, nausea, diarrhea, stomach pain, and fever. It frequently leads to hemolytic anemia and methemoglobinemia. Case presentation: A 2 year 5 month old developmentaly normal male child was brought with complaints of fever for two days, high grade intermittent and not associated with chills and rigors, an alleged history of ingestion of approximately 1/4 of naphthalene ball (about 1 gm) at home. History of vomiting and passing of dark coloured urine for the past one day. Blood investigation showed CRP positive, methemoglobin 7.6%, Hb 6.7gm%, Total count 29,140 cells/mm3, Hyperbilirubinemia with indirect fraction predominence, elevated LDH, Peripheral smear study showed severe anemia, with marked anisopoikilocytosis and occasional normoblast suggestive of hemolytic picture, neutrophilic leucocytosis with toxic changes, and reactive thrombocytosis. Dark coloured urine with albumin 3+ noted. In view of anemia exchange transfusion was done and child was treated with oxygen via NRM, ascorbic acid, and NAC infusion, Further treatment given symptomatically and appropriately for 6 days and discharged on recovery with advice. Conclusion: This case highlights the importance of early recognition and prompt management of naphthalene - induced methemoglobinemia and hemolytic anemia. A thorough history, clinical examination, and appropriate laboratory investigation are essential for accurate diagnosis. Public awareness and preventive education about the potential toxicity of naphthalene-containing products in households with young children are very crucial.