A Survey of Ighthyosis Vulgaris in Israel

Abstract

SUMMARY.— Three hundred and sixty‐six patients with ichthyosis vulgaris were examined, including 229 with X‐linked recessive ichthyosis (X.L.I.) and 137 with autosomal dominant ichthyosis (A.D.I.), among the Jewish population of Israel. The minimal incidence of the disease in this population is about 1:6500. The disease affected the various ethnic groups differently; among Iraqi Jews there were cases only of X.L.I, compared with only A.D.I, among Indian Jews. The disease appeared in both forms in 95% of cases before 5 years of age, and half of the cases showed improvement in the course of time; 80%‐95% of the patients noted improvement in the summer months. A family history of “atopy” was found only in about a third of cases of A.D.I, and in none of those with X.L.I. The most pronounced clinical features of the disease were found over the anterior aspect of the legs, and equally in both forms. Follicular keratosis of the arms and hyperkeratosis with prominent creases of the palms and soles were found only in A.D.I. The histological findings were diagnostic, especially in those areas where the scaling was obvious, and thus it is recommended to biopsy the anterior shin region. The histology in X.L.I, showed compact laminated hyperkeratosis, with thickening of the granular layer; whereas, in A.D.I., the hyperkeratosis was usually of basket‐weave type, with a thin or absent granular layer. The sweat glands were normal in structure and number in both forms, while the sebaceous glands were absent only in cases of A.D.I.

Absence of the granular layer and keratohyalin define a morphologically distinct subset of individuals with ichthyosis vulgaris

“…In an attempt to determine the prevalence of absent granular in individuals with IV while avoiding ascertainment bias caused by including family members, a subset of moderately to severely affected individuals recruited as part of a clinical investigation was studied (Table 1, HS 204–205, 207–215). Four (95% confidence interval, 1–7) of these individuals had no granular layer by light microscopy and no KHG by electron microscopy.…”

“…The ichthyoses are a heterogeneous group of scaling disorders that are classified on the basis of clinical appearance, histopathologic change, and inheritance (1,2). Two common forms of ichthyosis predominate, autosomal dominant ichthyosis vulgaris (IV) (incidence 1 : 250–1 : 5300, 3) and X‐linked recessive ichthyosis (RXLI) (incidence 1 : 2000–1 : 9500, 3–6). Of the two, diagnosis of IV remains difficult.…”

Review: Genetics of steroid sulphatase deficiency and X‐linked ichthyosis

“…Wells and Kerr (1966) estimated a prevalence in the County of Berkshire including the Borough of Reading, England to be 1 per 6190 males (0.16 per 1000). A similar estimate of prevalence was derived for Israel by Ziprkowski and Feinstein (1972) who found 1 in 5200 males (0.19 per 1000) to be affected. The disease is widely distributed geographically and is found among people of varying genetic background as further evidenced by the origins of the 25 patients studied by Shapiro et aI.…”

Morphology of Filaggrin-Depleted Epidermis

“…On electron microscopy, residual F-type keratohyalin granules appear crumbly [ 41 , 42 ] An increased number of SC cell layers, which histologically becomes apparent in an orthohyperkeratotic or basket-weave-like SC (see Fig. 2.1a ) [ 43 ], and a higher number of suprabasal, Ki-67-positive cells are seen in double-allele mutant IV (see Fig. 2.1d ); however, the proliferation rate is much lower compared to lamellar ichthyosis or psoriasis.…”