Plasma zinc, copper and serum ceruloplasmin levels of autism spectrum disorder children in Bangladesh

Neural and cognitive processes require zinc and copper homeostasis and a normal zinc/copper ratio. Ceruloplasmin, an intrinsic antioxidant protein, maintains copper homeostasis, which might also influence autism spectrum disorder (ASD). ASD children are frequently reported with altered levels of these elements with wide geographical variations. This study evaluated any alteration in plasma zinc, copper, zinc/copper ratio and serum ceruloplasmin levels in Bangladeshi ASD children with respect to healthy controls. A cross-sectional study was conducted on 67 children aged 2 to 9 years of both sexes. Among them, 35 had ASD, while 32 were age, sex and body mass index (BMI) matched apparently healthy children. Plasma zinc and copper levels were estimated by the flame atomic absorption spectrophotometry method. Serum ceruloplasmin levels were estimated by the immunoturbidimetric method. Zinc and zinc/copper ratio in the 2-9 years old ASD children group were significantly lower (p=0.032 and p=0.002 respectively). On the other hand, copper (p=0.020) and ceruloplasmin (p = 0.045) levels were significantly higher than those of apparently healthy children. ASD was significantly associated with zinc deficiency (p=0.000) and copper toxicity (p=0.05). All children were again divided into 2-5 and 6-9 years age groups according to laboratory reference values for zinc and copper. Copper toxicity was significantly associated with ASD in the 2-5 years old age group (p=0.011), with a significant difference in plasma copper levels (p=0.009) and zinc/copper ratio (p=0.001) but not serum ceruloplasmin levels (p=0.110) compared to healthy controls. Serum ceruloplasmin was positively associated with plasma copper in ASD children of all age groups. This study shows that ASD in Bangladesh can be associated with low plasma zinc and high plasma copper and serum ceruloplasmin levels.