Dysgeusia Due to Zinc Deficiency After Pancreaticoduodenectomy Requiring Continuous Intravenous Zinc Supplementation: a Case Report and Literature Review

Background: Zinc is mainly absorbed in the duodenum and proximal jejunum, which are removed during pancreaticoduodenectomy (PD). Little is known about the adverse oral events and skin disorders caused by zinc deficiency after PD. Herein, we reviewed studies regarding the development of zinc deficiency after PD and presented the case of a patient with zinc deficiency after PD, who required home intravenous zinc replacement.Case presentation: A 73-year-old woman with glossitis, taste disorder, and acrodermatitis enteropathica-like eruption on her fingers presented to the Division of Dentistry and Oral Surgery 69 days after PD. Her serum zinc level markedly decreased to 30 μg/dL. Oral zinc administration was inadequate to treat hypozincemia after PD; therefore, multi-trace elements were injected intravenously under readmission. Her serum zinc levels recovered, and the lesions gradually improved. Furthermore, a central venous port was implanted to maintain normal serum zinc levels, and she continued self-injecting zinc at home.Conclusion: Zinc deficiency after PD rarely occurs. The clinical oncologist community, including dentists responsible for the oral care of cancer patients, should be aware of dysgeusia associated with zinc deficiency after cancer surgery, as well as that induced by chemotherapy or head and neck radiation therapy.

Heterologous expression of the human ZIP4 zinc transporter in Saccharomyces cerevisiae

The human (h) transporter, hZIP4 is the primary zinc importer in the intestine and is also expressed in a variety of organs such as the pancreas and brain. Dysfunction of hZIP4 can result in the zinc deficiency disease acrodermatitis enteropathica (AE), which disrupts digestive and immune system homeostasis. Structure-function studies of hZIP4 have been greatly hindered by the absence of a robust heterologous expression system. Here, we report the heterologous expression of hZIP4 in Saccharomyces cerevisiae. Both a wild type and a mutant S. cerevisiae strain, in which the endogenous zinc transporters are deleted, were used to test the expression and localization of an hZIP4-GFP fusion protein. A full-length hZIP4-GFP and a truncated membrane domain only (mhZIP4-GFP) protein were successfully produced and targeted to the plasma membrane in yeast.

A Missense Variant in SLC39A4 in a Litter of Turkish Van Cats with Acrodermatitis Enteropathica

In a litter of Turkish Van cats, three out of six kittens developed severe signs of skin disease, diarrhea, and systemic signs of stunted growth at 6 weeks of age. Massive secondary infections of the skin lesions evolved. Histopathological examinations showed a mild to moderate hyperplastic epidermis, covered by a thick layer of laminar to compact, mostly parakeratotic keratin. The dermis was infiltrated with moderate amounts of lymphocytes and plasma cells. Due to the severity of the clinical signs, one affected kitten died and the other two had to be euthanized. We sequenced the genome of one affected kitten and compared the data to 54 control genomes. A search for private variants in the two candidate genes for the observed phenotype, MKLN1 and SLC39A4, revealed a single protein-changing variant, SLC39A4:c.1057G>C or p.Gly353Arg. The solute carrier family 39 member 4 gene (SLC39A4) encodes an intestinal zinc transporter required for the uptake of dietary zinc. The variant is predicted to change a highly conserved glycine residue within the first transmembrane domain, which most likely leads to a loss of function. The genotypes of the index family showed the expected co-segregation with the phenotype and the mutant allele was absent from 173 unrelated control cats. Together with the knowledge on the effects of SLC39A4 variants in other species, these data suggest SLC39A4:c.1057G>C as candidate causative genetic variant for the phenotype in the investigated kittens. In line with the human phenotype, we propose to designate this disease acrodermatitis enteropathica (AE).

Acquired Zinc Deficiency Mimicking Acrodermatitis Enteropathica in a Breast-Fed Premature Infant

We present a case of a transient acquired zinc deficiency in a breast-fed, 4-month-old-male prematurely born infant, with acrodermatitis enteropathica-like symptoms such as crusted, eroded, erythemato-squamous eruption in periorificial and acral patterns. The laboratory investigations showed low zinc levels in the infant’s and the mother’s serum and in the mother’s milk; genetic analysis did not show any mutation in the SLC39A4 gene, involved in acrodermatitis enteropathica. Acquired zinc deficiency is often found in premature infants because of their increased requirement, the low serum and milk zinc levels in breastfeeding women being also an important risk factor, as in this case. A prompt zinc supplementation is essential for the good prognosis of the disease.