Congenital poisoning after maternal parenteral mercury administration

Abstract

This is the case of a full-term baby girl, born to a mother with a history of parenteral inorganic mercury administration. Thirteen years prior, this mother injected 1mL of inorganic mercury in her right forearm, was subsequently hospitalized, but never received chelation treatment. Her first trimester blood and urine mercury concentration were found to be elevated at 28μg/L (normal <10μg/L) and 162 μg/L (normal <20μg/L) respectively. Her chest x-ray also revealed multiple small punctate metallic densities within the lower lung fields. The remainder of the prenatal course was uneventful. The baby was born at 40 weeks of gestation via uncomplicated caesarian section, and on day of life 3, blood mercury concentrations were found to be 20μg/L (normal <20μg/L). The baby, however, remained asymptomatic throughout her hospital stay and on outpatient follow up. She is now two years old. Mercury poisoning in the pediatric population remains a concern, and knowledge of exposure and health effects continues to be relevant as newer uses and modes of exposure are discovered. This case report illustrates a rare perinatal exposure scenario, and, while the mother and child were essentially asymptomatic, the case serves to raise awareness of the many ways in which fetuses, infants, and children may still be exposed to the harmful effects of mercury. This case underscores the need for careful environmental history taking in pregnancy, after birth, and ideally in the pre-conception period as well.