Zinc Deficiency, Transient Neonatal; Tnzd

Description

Transient neonatal zinc deficiency occurs in breast-fed infants as a consequence of low milk zinc concentration in their nursing mothers, which cannot be corrected by maternal zinc supplementation. A large amount of zinc, an essential trace mineral, is required for normal growth particularly in infants, and breast milk normally contains adequate zinc to meet the requirement for infants up to 4 to 6 months of age. Zinc deficiency can lead to dermatitis, alopecia, decreased growth, and impaired immune function. The disorder shows autosomal dominant inheritance with incomplete penetrance (summary by Chowanadisai et al., 2006).Some aspects of TNZD resemble the more severe disorder acrodermatitis enteropathica (AEZ ), an autosomal recessive disorder caused by mutation in the zinc transporter SLC39A4 (OMIM ). However, infants with transient neonatal zinc deficiency do not require zinc supplementation following weaning and have normal zinc absorption, whereas those with AEZ require lifelong zinc supplementation (summary by Chowanadisai et al., 2006).

Clinical Features

• Alopecia
• Abnormality of the skin
• Eczema
• Inflammatory abnormality of the skin
• Abnormal intestine morphology
• Abnormality of zinc homeostasis