Plaque (lamellar) ichthyosis (LI) (OMIM: 606545) is a severe, autosomal recessive, genetically heterogeneous skin disease characterized by severe hyperkeratosis, large, plate-like dark scales, and generalized erythroderma. LI usually presents from birth or in the first few months of life and has a progressive course. The clinical differentiation between LI and other forms of congenital ichthyosis poses a significant challenge due to the substantial number of overlapping symptoms, which complicates the diagnostic process. This study aims to elucidate the clinical manifestations of congenital ichthyosis, with a particular focus on the dermatological presentations observed in two patients. Whole genome sequencing was performed. In both cases, the same pathogenic nucleotide sequence variant in exon 7 of the ALOXE3 gene was identified, in one case in a compound-heterozygous state and in another in a homozygous state, that confirmed the diagnosis of LI. Making a definitive and accurate differential diagnosis of autosomal recessive congenital ichthyosis (ARCI) forms acquires an integrated multidisciplinary approach that combines epidemiologic, clinical, and genetic data. That also could provide novel insights into the nature of the disease and could help to develop mutation screening strategies.