A novel LEMD3 pathogenic variant in a son and mother with osteopoikilosis.

Elmaogullari S, Yildiz AE, Demir S, Gürkan H, Uçaktürk SA. A novel LEMD3 pathogenic variant in a son and mother with osteopoikilosis. Turk J Pediatr 2019; 61: 594-598. Osteopoikilosis (OPK) is a rare, benign condition characterized by osteosclerotic foci that occur in the epiphyses and metaphyses of long bones, wrists, feet, ankles, pelvis, and scapulae. We report a 16-year-old boy and his mother incidentally found to have sclerotic lesions on X-ray. Both of them were asymptomatic and the bone scan of the boy ruled out osteoblastic metastases. We have shown that the boy and his mother have a previously unknown pathogenic variant of the LEMD3 gene, supporting the diagnosis of osteopoikilosis.

Biochemical and ultrastructural demonstration of elastin accumulation in the skin lesions of the Buschke-Ollendorff syndrome.

The Buschke-Ollendorff syndrome is an association of cutaneous lesions, dermatofibrosis lenticularis disseminata, with osteopoikilosis. This condition is inherited in an autosomal dominant pattern. In order to clarify the biochemical nature of the skin lesions, we have examined 12 patients with the Buschke-Ollendorf syndrome, representing 2 unrelated kindreds. Histologically, the lesions were characterized by excessive amounts of unusually broad, interlacing elastic fibers in the dermis. Digestion of skin secretions with pancreatic elastase completely removed these fibers. Electron microscopy of the dermis further revealed markedly branched elastic fibers without fragmentation. The accumulation of elastin in the skin was also demonstrated by measurements of desmosine employing a radioimmunoassay. The desmosine content of the skin lesions increased 3- to 7-fold when compared to the skin either from healthy controls or from uninvolved skin adjacent to a lesion. The results indicate that the skin lesions of the Buschke-Ollendorff syndrome are connective tissue nevi of the elastin type. Cell cultures from these patients may provide a convenient model to study the control mechanisms involved in elastin metabolism.

Buschke-Ollendorff syndrome associated with elevated elastin production by affected skin fibroblasts in culture.

Buschke-Ollendorff syndrome (BOS; McKusick 16670) is an autosomal dominant connective-tissue disorder characterized by uneven osseous formation in bone (osteopoikilosis) and fibrous skin papules (dermatofibrosis lenticularis disseminata). We describe two patients in whom BOS occurred in an autosomal dominant inheritance pattern. The connective tissue of the skin lesions showed both collagen and elastin abnormalities by electron microscopy. Cultured fibroblasts from both patients produced 2-8 times more tropoelastin than normal skin fibroblasts in the presence of 10% calf serum. Involved skin fibroblasts of one patient produced up to eight times normal levels, whereas apparently uninvolved skin was also elevated more than threefold. In a second patient, whose involvement was nearly complete, elastin production was high in involved areas and less so in completely involved skin. Transforming growth factor-beta 1 (TGF beta 1), a powerful stimulus for elastin production, brought about similar relative increases in normal and BOS strains. Basic fibroblast growth factor, an antagonist of TGF beta 1-stimulated elastin production, was able to reduce elastin production in basal and TGF beta 1 stimulated BOS strains. Elastin mRNA levels were elevated in all patient strains, suggesting that Buschke-Ollendorff syndrome may result, at least in part, from abnormal regulation of extracellular matrix metabolism that leads to increased steady-state levels of elastin mRNA and elastin accumulation in the dermis.

[Changes in phosphorus-calcium metabolism in osteopoikilosis (Buschke-Ollendorf syndrome)]. / Alteraciones del metabolismo fosfocálcico en la osteopoiquilia (síndrome de Buschke-Ollendorf).

Osteopoikilosis has always been described as a radiological finding of no clinico-biological significance with no deforming consequences for the skeleton. The authors present three cases with a past family history (mother suffered from osteopoikilosis and two sons with Buschke-Ollendorf syndrome) in whom we found alterations of phosphorus and calcium metabolism, this not having been previously reported in the literature.