Dystrophic calcinosis cutis in subacute lupus

Dystrophic calcinosis cutis is known to be associated with various connective tissue disorders but to the best of our knowledge has never been reported in subacute cutaneous lupus erythematosus (SCLE), a distinctive cutaneous subset in the spectrum of lupus erythematosus. It occurs without calcium and phosphorus metabolic abnormalities and may be localized or generalized. We report a patient with SCLE who developed calcinosis cutis and had normal serum calcium and phosphorus levels and, interestingly, a normal concentration of blood ionized calcium. This latter, which represents the active form in the total amount of blood calcium, is a parameter only rarely assessed in patients with dystrophic calcinosis cutis. Thus, other pathogenic factors should be investigated to clarify the pathophysiology of the dystrophic type of calcification.     

Death from coronary calcinosis occurring in the baby of a mother presenting with pseudoxanthoma elasticum

This paper reports the case of a baby with coronary calcinosis born to a mother suffering from pseudoxanthoma elasticum. The aetiology of infantile coronary calcification is discussed, and the point is made that the dystrophic type is a disease of elastic tissue. Both conditions are rare genetic diseases and show dystrophic changes of the elastic tissue.     

Mammographic findings in pseudoxanthoma elasticum

BACKGROUND: There have been isolated case reports of arterial and skin calcification in mammograms of patients with pseudoxanthoma elasticum (PXE), and unpublished anecdotes of many women with PXE undergoing breast biopsy for evaluation of microcalcifications. OBJECTIVE: Our aim was to systematically evaluate mammography and breast pathology in PXE. METHODS: The mammograms of 51 women with confirmed PXE were compared with those of a control sample of 109 women without PXE, noting each of the following characteristics on each mammogram: breast density, skin thickening, skin microcalcifications, vascular calcification, breast microcalcifications and macrocalcifications, and masses. The characteristics of the 2 samples were compared using the 2-tailed t test with a pooled estimate of variance. The indications for mammography and data for each of the mammographic findings were analyzed using the chi(2) test. Available breast biopsy material was reviewed. RESULTS: The PXE and control groups were similar in age and indications for mammography. There was a statistically significant increase in skin thickening, vascular calcification, and breast microcalcifications in the PXE group (P <.001 each). Breast density, masses, macrocalcifications, and skin calcification did not differ statistically in the 2 groups, but no control patient had axillary calcification, or both vascular calcification and microcalcifications (P <.001). Nearly 1 in 7 of the patients with PXE demonstrated at least 3 of the following: microcalcifications, skin calcifications, vascular calcification, and skin thickening; whereas none of the control group did. Histopathologic findings of breast tissue showed calcification of dermal elastic fibers, subcutaneous arteries, and elastic fibers of the deep fascia and interlobular septae of the fat adjacent to breast parenchyma. CONCLUSION: Breast microcalcification and arterial calcification are not rare in the normal population and are not of diagnostic value. The presence of both of these findings, especially with skin thickening or axillary skin calcification, should suggest a diagnosis of PXE. The majority of breast calcifications in PXE are benign.     

Chequered localized pseudoxanthoma elasticum: a variety of Christensen's exogenous pseudoxanthoma elasticum?

We report a very curious case of a condition which has never been described before. Its features are comparable but not quite identical with those of Christensen's saltpetre-induced PXE which the author considers to be an exogenous variety of pseudoxanthoma elasticum. Since our case appeared spontaneously without any accidental episode we prefer to designate it under the name 'localized PXE'. The chequered appearance of the lesions seems to be the characteristic feature of the disease.     

Periumbilical perforating pseudoxanthoma elasticum.

Periumbilical pseudoxanthoma elasticum (PXE) with transepidermal elimination of altered elastica presented a distinctive clinical pattern in six middle-aged, multiparous women. Other sites usually affected in PXE were spared. The possible genetic predisposition to PXE of these patients found its expression in the periumbilical skin, a site exposed to the trauma of multiple pregnancies. The extruded elastica had tinctorial properties that were characteristic of PXE. The clinical picture in our cases differs from clasic PXE. A peculiar acquired cutaneous PXE is not excluded.     

Selected disorders of connective tissue: pseudoxanthoma elasticum, cutis laxa, and lipoid proteinosis

There has been progress made in the understanding of 3 Mendelian disorders: pseudoxanthoma elasticum, cutis laxa, and lipoid proteinosis cutis and mucosae. While they are primary connective tissue diseases, their names imply a connection to the skin, and in fact, it is often the dermatologist who makes the diagnosis. It seems rational that defects in various extracellular matrix proteins cause lipoid proteinosis or subtypes of cutis laxa, yet the discovery of a liver- and kidney-based transmembrane transporter as the culprit of pseudoxanthoma elasticum was rather surprising and may shed new light on elastic tissue homeostasis.     

Metastatic calcinosis cutis

Calcinosis cutis may be associated with metastatic calcification, dystrophic calcification, tumoral calcinosis, or may be deemed idiopathic. The association of cutaneous calcification with metastatic or tumoral calcinosis is quite rare. A case of metastatic calcinosis cutis in a woman with chronic renal failure and secondary hyperparathyroidism is presented. Other causes of calcinosis cutis are discussed briefly.     

弹力纤维假黄瘤一例

患者男,57岁。颈部密集淡黄色小丘疹8年。组织病理示扭曲、断裂的嗜红纤维。弹力纤维染色可见变性弹性纤维。诊断：弹力纤维假黄瘤。     

Molecular genetics of pseudoxanthoma elasticum

Pseudoxanthoma elasticum (PXE), a systemic heritable connective tissue disorder, is characterized by progressive calcification of elastic structures in the skin, the eyes and the cardiovascular system, with considerable intra- and interfamilial phenotypic variability. Recently, underlying genetic defects have been identified in the ABCC6 gene, which resides on the chromosomal locus 16p13.1 and encodes the MRP6 protein, a member of the ATP-binding cassette (ABC) family of proteins. The affected individuals are homozygous or compound heterozygous for a spectrum of genetic lesions, including nonsense and missense mutations, or deletions and splice-site alterations, confirming the autosomal recessive nature of this condition. Analysis of the deduced primary sequence suggests that MRP6 is a transmembrane transporter, but its function has not been delineated yet. Surprisingly, however, MRP6 is expressed primarily, if not exclusively, in the liver and the kidneys, suggesting that PXE may be a primary metabolic disorder with secondary involvement of elastic fibers. Identification of mutations in the ABCC6 gene in PXE provides a means for prenatal and presymptomatic testing in families at risk for recurrence. DNA-based analyses will also identify heterozygous carriers who may be at risk for development of limited manifestations of the disease as a result of compounding genetic factors and/or environmental modifiers.     

Fingertip calcinosis cutis

Calcinosis cutis, a rare disorder caused by an abnormal deposit of calcium phosphate into the skin, is observed in a variety of disorders. Peculiar conditions feature skin calcifications in children and may have an iatrogenic origin. The unusual case of a baby showing periodic transepidermal elimination of calcified nodules from her fingertips is reported. In this case, fingertip calcinosis cutis was probably caused by ischemic damage due to the venous obstruction that occurred during intensive care in the neonatal period.     

Trace element analyses in pseudoxanthoma elasticum

The dermis and sera of 11 patients with pseudoxanthoma elasticum (PXE) were analyzed by several techniques which test for the presence and quantity of trace elements (Fe, Ni, Co, Cu, Mn, Cr, Zn, Pb, Cd, Al, S, K, Cl, Ca and P). The investigative methods included 1) electron microscopic point X-ray microanalysis, 2) inductively coupled plasma atomic emission spectrophotometric analysis (ICP-AES), 3) X-ray diffraction analysis and/or 4) atomic absorption spectro-photometric analysis. 1) Among 7 specimens of dermis showing histological degeneration of the elastic fibers, 2 showed prominent levels of A1. In early degeneration of the elastic fibers, Ca was present in only small amounts; however, in more fully developed lesions, large quantities of both Ca and P were found, while Fe, Co, Ma and Zn were detected in trace amounts. 2) ICP-AES analysis confirmed large deposits of Al, Ca, and P in diseased dermis (Al: 32.1 ppm wet tissue); other elements were found in normal quantities. Al was not detected in the control dermis. 3) X-ray diffraction analysis suggested the pattern of hydroxyapatite [Ca₁₀(PO₄)₆(OH)₂], which indicates that most of the Ca exists in a crystalline form. 4) Atomic absorption spectrophotometric analysis confirmed a large concentration of Al (11–21 μg/dl, mean=17.2; normal <10) in all test patient's sera. The combined analysis revealed an increased amount of Al in patient's sera as well as in the elastic fibers of the dermis at an early stage of this disease (PXE). These findings suggest a possible role for Al in the pathogenesis of PXE.