Osteopoikilosis (OP) is a rare genetic bone dysplasia that causes dense patches in the trabecular bone and occurs in one in 50,000 people. The exact cause is unknown, but it could be due to mutations in the LEM domain-containing gene 3. Two cases were discovered incidentally in a clinic. The first case involved the mother, a 35-year-old woman with type 2 diabetes and dyslipidemia who presented with left ankle and right forearm pain after falling downstairs. Physical examination revealed mild swelling and tenderness at the left ankle, and X-ray examination revealed multiple small sclerotic lesions. The patient was diagnosed with OP. Analgesics, ankle support, and follow-up care were provided. The second case involved the son, a 14-year-old boy who had occasional pain in his right foot. A physical examination was normal. An X-ray of the right foot showed multiple homogeneous sclerotic lesions. He was diagnosed with familial OP and given analgesics for his pain.

Osteopoikilosis (OP) is a rare autosomal dominant sclerosing bone disease, caused by heterozygous mutations in the LEMD3 gene. It is characterised by numerous focal lamellar bone compact deposits in the spongiosa. In this case report, we describe a famliar case of OP and review the literature.

Melorheostosis, a rare mesenchymal dysplasia of bone, generally affects about 0.001% of people globally with about 400 cases total being reported. Melorheostosis of the hand, especially in the pediatric population, has been seldom reported. Previous studies have investigated potential genetic mutations associated with melorheostosis however, questions still remain regarding effective treatment options for this disease. This case report describes a unique case of pediatric melorheostosis of the hand and further clarifies current theories on melorheostosis with regards to pathogenesis, best treatment practices, and future research.

Melorheostosis (MEL) is an uncommon, sclerosing disease, characterised by hyperostosis of long bones, resembling the flowing of candle wax. The disease is sporadic and the pathogenesis is still poorly understood. Occasionally, the same family can include individuals with MEL and Osteopoikilosis (OPK), a disease characterised by multiple round foci of increased bone density. LEMD3 gene mutations are related to OPK and Buschke-Ollendorff Syndrome, a genetic condition in which an association between MEL, OPK and skin lesions is observed. In rare cases, LEMD3 mutations and recently mosaic MAP2K1 gene mutations have been correlated to MEL suggesting that somatic mosaicism could be causative of the disease. In this study, we described the clinical, radiological and molecular findings of 19 individuals with MEL and 8 with OPK and compared the results to the medical literature. The molecular analyses of this case series corroborate the available data in the medical literature, indicating that LEMD3 germline mutations are not a major cause of isolated MEL and reporting five further cases of OPK caused by LEMD3 germline mutations.

Osteopoikilosis is an inherited condition with autosomal dominant trait resulting in sclerotic foci throughout the skeleton. It has been suggested that loss-of-function mutations of LEMD3 gene located on 12q14.3 result in osetopoikilosis. A bp heterozygote deletion was detected in our patient at the cytosine nucleotide at position 1105 with molecular genetic analysis. Although this mutation has not been previously described, it was considered to be the most likely cause of the disease in our patient due to frame shift and premature stop codon formation. As in our case, three phase bone scintigraphy and whole body imaging did not reflect the true extent of lesion sites and lesion activity. SPECT/CT images could reflect lesion location and activity more accurately, and could be a good alternative for differential diagnosis of unexplained bone pain and sclerotic lesions in one examination.
Osteopoikiloz kemik doku boyunca kemik adacıkları ile karakterize, otozomal dominant geçiş gösteren herediter bir hastalıktır. Mevcut literatürde, 12q14.3 üzerinde bulunan LEMD3 genindeki mutasyonların sebep olduğu gösterilmiştir. Hastamızda yapılan moleküler genetik analizde ‘Yeni Nesil Dizi Analizi’ 1105. pozisyondaki sitozin nükleotidinde bir bp’lik heterozigot delesyon tespit edilmiştir. Bu mutasyon, daha önceden literatürde tanımlanmamış olmakla birlikte; çerçeve kaymasına neden olması ve erken stop kodon oluşturması sebebiyle yüksek olasılıkla hastalık nedeni olarak değerlendirilmiştir. Ancak üç fazlı kemik sintigrafisi ve tüm vücut taraması, bu olguda olduğu gibi gerçek lezyon sayısı ve lezyon aktivitesini yansıtmamaktadır. SPECT/BT görüntüleme bu açıdan iyi bir seçim olarak görülmektedir. Anahtar kelimeler: LEMD3 geni, osteopoikiloz, Tc-99m MDP, SPECT/BT.

BACKGROUND: Osteopoikilosis is a rare and benign autosomal dominant genetic disorder, characterized by a symmetric but unequal distribution of multiple hyperostotic areas in different parts of the skeleton. Recent studies have reported loss-of-function mutations in the LEM domain containing 3 (LEMD3) gene, encoding an inner nuclear membrane protein, as a cause of osteopoikilosis.
METHODS: We investigated LEMD3 gene in a three-generation family from China, with six patients affected with osteopoikilosis. Peripheral blood samples were collected from family members and 100 healthy controls. All exons of the LEMD3 gene and adjacent exon-intron sequences were amplified by PCR and subsequently sequenced.
RESULTS: A novel heterozygous c.2612_2613insA (p.Y871X) mutation in exon 13 of LEMD3 was identified, which resulted in a frame shift predicted to generate a premature stop codon at amino acid position 871. The mutation co-segregates with the osteopoikilosis phenotype and was not found in 100 ethnically matched controls.
CONCLUSIONS: We identified a new mutation in LEMD3 gene, accounting for the familial case of osteopoikilosis. In addition we also review the clinical manifestation, diagnosis and treatment of osteopoikilosis.