Classic pseudoxanthoma elasticum in a patient with sickle cell disease

Classic pseudoxanthoma elasticum in a girl with sickle cell disease

A pseudoxanthoma elasticum (PXE)-like phenotype develops in a subset of patients with inherited hemoglobinopathies. Although PXE tissue changes are thought to develop in the absence of ABCC6 mutations in patients with beta-thalassemia, ABCC6 mutations have not been well evaluated among sickle cell disease patients with PXE-like disease. To our knowledge, we describe the first patient with sickle cell disease, PXE skin findings, and two confirmed pathogenic ABCC6 mutations. This case suggests that ABCC6 testing is warranted for sickle cell disease patients with the PXE-like phenotype and that the pathogenesis of PXE manifestations in beta-thalassemia and sickle cell disease may differ.

Histopathology of pseudoxanthoma elasticum and related disorders: histological hallmarks and diagnostic clues

Among ectopic mineralization disorders, pseudoxanthoma elasticum (PXE)-a rare genodermatosis associated with ocular and cardiovascular manifestations-is considered a paradigm disease. The symptoms of PXE are the result of mineralization and fragmentation of elastic fibers, the exact pathophysiology of which is incompletely understood. Though molecular analysis of the causal gene, ABCC6, has a high mutation uptake, a skin biopsy has until now been considered the golden standard to confirm the clinical diagnosis. Although the histological hallmarks of PXE are rather specific, several other diseases-particularly those affecting the skin-can present with clinical and/or histological characteristics identical to or highly resemblant of PXE. In this paper, we will summarize the histopathological features of PXE together with those of disorders that are most frequently considered in the differential diagnosis of PXE.

[Screening for sickle cell disease retinopathy in the north of France]

OBJECTIVE

To study the frequency and the severity of retinopathy in adult patients with sickle cell disease in the north of France.

PATIENTS AND METHODS

Patients with sickle cell disease aged more than 18 years old were consecutively referred for screening of sickle cell retinopathy in the ophthalmology department from December 2005 to March 2008. Complete ophthalmologic examination with dilated funduscopy was performed in each patient. Fluorescein angiography was performed in cases with ischemic retinopathy. Goldberg and Penman classifications were used to grade retinopathy severity.

RESULTS

Fifty-five patients (100 eyes) were included (26 S/S, 9 S/C, 12 S/B, 3 S/S with hereditary persistence of fetal hemoglobin). Sickle cell retinopathy is more severe in patients with the S/C genotype than the S/S and S/B genotypes. Proliferative retinopathy is more common in S/C patients than S/S and S/B patients (S/C vs S/S, p=0.001; S/C vs SB, p=0.01). A qualitatively abnormal vascular border (type II) is also more frequent in S/C patients than S/S and S/B patients (S/C vs S/S, p=0.001; S/C vs SB, p=0.01). No proliferative retinopathy was found in patients with S/S and hereditary persistence of fetal hemoglobin syndrome.

CONCLUSIONS

Screening is useful to detect sickle cell retinopathy, particularly in the adult population, to prevent complications from proliferative retinopathy.

Use of pimecrolimus cream in disorders other than atopic dermatitis

BACKGROUND

Pimecrolimus is indicated for treatment of atopic dermatitis and has been evaluated in many other disorders.

OBJECTIVE

To review the efficacy of pimecrolimus in treatment of disorders other than atopic dermatitis.

METHODS

We performed a PubMed search of the English-language literature using the key word "pimecrolimus." We reviewed articles reporting the use of pimecrolimus in disorders other than atopic dermatitis and classified them by the type of study used to evaluate efficacy.

RESULTS

Randomized, double-blind studies have shown that pimecrolimus is superior to vehicle in treatment of seborrheic dermatitis, hand dermatitis, and asteatotic eczema but have yielded conflicting results regarding intertriginous psoriasis and vitiligo. Open-label studies involving four or more patients have shown favorable results in many disorders, including contact dermatitis, rosacea, lichen sclerosus, and oral and genital lichen planus. Case reports have shown that topical pimecrolimus may be useful in cutaneous graft-versus-host disease, lichen striatus, cutaneous lichen planus, and many other disorders.

CONCLUSIONS

Topical pimecrolimus appears to be an effective treatment for many disorders other than atopic dermatitis, especially seborrheic dermatitis, hand dermatitis, and asteatoic eczema. It may be effective in many other disorders, but its role in these disorders remains to be clarified by additional studies.