Galli?Galli disease is an acantholytic variant of Dowling?Degos disease

Abstract

Dowling-Degos disease (DDD; MIM 179850) is a rare autosomal dominant disorder characterized by reticulate flexural hyperpigmentation associated with hyperkeratotic papules, pitted perioral scars and comedo-like lesions or cysts. 1 Characteristic histopathological features include filiform epithelial downgrowths of the rete ridges, typically involving the follicular infundibulum, basilar hyperpigmentation and dermal melanosis. Follicular retention cysts and perivascular mononuclear infiltrates can also be present. 1 Galli-Galli disease is a term that has been used to describe patients displaying prominent acantholytic changes on histology, in addition to clinical and pathological features resembling those of DDD. 2 Two mutations in KRT5, encoding one of the two major basal epidermal keratin intermediate filaments, were recently reported to underlie DDD in a number of European cases. 3 In the present study, we report a novel mutation in KRT5 in a patient with clinical and histopathological features typical of Galli-Galli disease. Case and methods

The molecular basis of human keratin disorders

“…Recently, a mutation which is predicted to disrupt the KRT5 initiation codon leading either to haploinsuYciency or the synthesis of a N-deleted K5 mutant protein has been reported in a patient with Galli-Galli disease (Sprecher et al 2007). Since the same mutation (p.Ile140 fs) has been reported both in Galli-Galli disease and in DDD (Betz et al 2006;Sprecher et al 2007), Galli-Galli disease seems to be merely a variant of DDD.…”

Acromelanosis Albo-Punctata: A Distinct Inherited Dermatosis with Acral Spotty Dyspigmentation without Systemic Involvement

“…The acantholytic variant of Dowling-Degos disease is called Galli-Galli disease [48]. These two entities are caused by mutations in the keratin 5 gene (KRT5) [48]. By correlating genotype-phenotype Hanneken et al [49] found that patients with the KRT5 mutation c.418dupA presented reticular hyperpigmentation in the flexural areas, whereas in patients with a more disseminated pattern consisting of hyperpigmented lentiginous maculae this mutation could not be revealed.…”

“…This is said to be more prominent in Dowling-Degos disease; in acropigmentation of Kitamura only a slight epidermal atrophy is present. The acantholytic variant of Dowling-Degos disease is called Galli-Galli disease [48]. These two entities are caused by mutations in the keratin 5 gene (KRT5) [48].…”

Dowling-Degos Disease: Case Report and Review of the Literature

“…The only disease which has unambiguous diagnostic criteria is DDD, with its specific genetic changes. Galli-Galli disease resembles DDD but reveals basal layer acantholysis upon histologic examination [11,12]; keratin mutations are found but presumably involve a region of the molecule which is essential to cell-cell adherence [13]. One could speculate that Galli-Galli disease lies somewhere between DDD and EBS with mottled hyperpigmentation.…”