Boys with X-linked ichthyosis appear normal at birth. The skin symptoms generally appear within the first year of life. Brownish scales that adhere to the skin are among the first signs of the disorder. The back and legs are most frequently involved early. The face, scalp, palms and soles, and hollows of the elbows and knees are usually spared.
In about half of adult males, comma-shaped corneal opacities occur in the eyes (seen on exam by an ophthalmologist), but they do not interfere with vision. Symptoms can improve markedly in the summer months and warm humid climates.
A small percentage of males may experience undescended testes (crytpchordism). These men may be at increased risk for contracting malignancies of the testes.
Women who are carriers of X-linked ichthyosis and give birth to sons with the disorder may experience a delay in labor or failure of labor to initiate. The enzyme defect can cause a decrease in production of maternal estriol in late pregnancy, which may affect labor and delivery. Low serum estriol levels detected by prenatal screening suggest the presence of a fetus with X-linked ichthyosis.