X-linked ichthyosis and ichthyosis vulgaris: comparison of their clinical features based on biochemical analysis

Abstract

Thirty cases of X-linked ichthyosis (XLI) and 32 cases of ichthyosis vulgaris (IV) were diagnosed by measuring the steroid sulphatase activity of peripheral blood lymphocytes or the electrophoretic mobility of serum LDL or both. The clinical features of the two conditions were then compared. In both diseases 60-66% of patients had a family history of the condition. Ichthyosis was noted at birth or immediately afterwards in 59% of the patients with XLI while it appeared in infancy in 68% of those with IV. Scales were mostly large and brown or dark brown in patients with XLI, while the majority of patients with IV had small brown or light brown scales. The distribution of the ichthyotic lesions differed in the two types of ichthyosis. On the trunk, the abdomen was more severely involved than the back in 63% of the cases with the XLI, whereas the back was more scaly than the abdomen in 44% of those with IV. On the extremities, the extensor surface was more severely affected than the flexor surface in both types. X-linked ichthyosis was characterized by the presence of lesions in the pre-auricular area, which were found in 93% of the cases with XLI, while only 17% of the IV patients had ichthyotic lesions at this site. Involvement of the preauricular area could be an important clinical feature for distinguishing XLI from IV.

Lipoprotein- und Apolipoproteinelektrophorese bei X-chromosomal-rezessiver Ichthyose

“…In allen Spuren stellt sich zunächst ein typisches Lipoproteinbandenmuster mit einer ausgeprägten β-Fraktion (einschließlich der anodisch direkt angrenzenden schwach ausgeprägten prä-β-Fraktion) sowie einer dazu noch weiter anodisch liegenden α-Fraktion dar. Im Unterschied zu früheren Arbeiten, die über eine normale elektrophoretische Mobilität der α-Fraktion (HDL) von XRI-Patienten berichten [7,9,10,11,13,16] Anmerkung: Die ausgeprägte Apo-B-100-Bande in Spur 8 kann im Sinne eines erhöhten Risikos für eine koronare Herzerkrankung des betroffenen Probanden interpretiert werden [19]. Im Vergleich der Spuren fällt in den Spuren 2 und 6 (XRI-Patienten) eine deutlich verlängerte Wanderungsstrecke (Entfernung vom Probenauftragungspunkt) auf.…”

“…Diese Beobachtung lässt sich für LDL mit deren erhöhtem Cholesterinsulfatgehalt erklären [7,10,13,16]. Diese Beobachtung lässt sich für LDL mit deren erhöhtem Cholesterinsulfatgehalt erklären [7,10,13,16].…”

“…von LDL und VLDL [9,11,20] in der Serumlipoproteinelektrophorese beschrieben. Deren Ursache liegt nach verschiedenen Autoren [7,13,16] …”

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

“…Of the two, diagnosis of IV remains difficult. The two disorders were initially distinguished by clinical findings and inheritance (3,7); however, following the demonstration of mutations in the steroid sulfatase gene in RXLI it became clear that the clinical distinction of IV from RXLI is difficult and sometimes incorrect (8–11). Similarly, light microscopy as a means of diagnosing IV is disputed.…”

Most "Sporadic" Cases of X-linked Ichthyosis are not De Novo Mutations

“…Cryptorchidism in patients, delayed labour in carriers and corneal opacities in both patients and carriers are features frequently associated with the condition (6^8). Ichthyosis vulgaris shares many clinical features with XLI and a di¡erential diagnosis must be made among both entities (9,10). XLI diagnosis is possible by determining the STS activity in leukocytes or other cell lines (11^13).…”