| A neonate presented with clinical, biochemical, endocrine and radiographic features consistent with vitamin d deficiency rickets of maternal origin. Persistent hypocalcemia and subsequent development of pancytopenia, hemolysis and hepatosplenomegaly prompted further studies that led to the diagnosis of infantile osteopetrosis. CONCLUSION: osteopetrosis is an important differential diagnosis of neonatal rickets and is not excluded by low vitamin D levels. ( info) |
12/238. Long-term follow-up of two children with a variant of mild autosomal recessive osteopetrosis undergoing bone marrow transplantation. Malignant autosomal recessive (AR) osteopetrosis represents an absolute indication for bone marrow transplantation (BMT). Over the last 15 years, almost 100 BMTs for osteopetrosis have been reported. The median age at transplant of most patients is 4 months. Very few cases of mild AR osteopetrosis have been described. Here, we report the good outcome of two cases of mild AR osteopetrosis with a follow-up of 5 and 6 years, respectively, after an HLA-identical sibling transplant undergone at 5 and 12 years of age, respectively. At the time of BMT, severe visual impairment was present in both children. Bone biopsy demonstrated hypermineralization with virtual obliteration of the medullary spaces, rare microfoci of hematopoiesis and marked deficiency in osteoclastic activity. Successful engraftment was complicated by hypercalcemia, controlled by a combination of bisphosphonate, phosphate infusions, vigorous hydration and calcitonin. Following BMT, radiological and histological findings showed extensive bone resorption with marked augmentation of the osteoclasts in normalized marrow. No improvement was observed in visual acuity, despite complete remodeling of skeletal abnormalities. We conclude that allogeneic BMT is the only chance of curing mild AR osteopetrosis. ( info) |
13/238. Higher osteoclastic demineralization and highly mineralized cement lines with osteocalcin deposition in a mandibular cortical bone of autosomal dominant osteopetrosis type II: ultrastructural and undecalcified histological investigations. In this study we report on histological and ultrastructural investigations of the mandibular cortical bone in a case of autosomal dominant osteopetrosis type II complicated by mandibular osteomyelitis. Histologically, there was a marked increase in the number and size of osteoclasts on the inner bone surface. An undecalcified preparation showed a pair of deeply stained (highly demineralized) and stain-phobic (highly mineralized) layers on the bone surface just beneath the osteoclasts. The layers were incorporated into the bone matrix during the remodeling process as thickened cement lines. A contact microradiogram of the cortical bone revealed highly mineralized layers at the cement lines, which were closely correlated with immunohistochemical evidence of deposition of osteocalcin at the thickened cement lines. Ultrastructural examination showed that the osteoclasts had a typical clear zone, but they were deficient in ruffled border formation and had numerous lysosomal vacuoles containing dense substances. An electron-dense amorphous material layer was present on the bone surface just beneath the osteoclasts as well as at the cement lines. The layer was partly composed of a short fibrillar material, and it partially revealed the lamellar structure. Consequently, an osteoclastic malfunction might be primarily involved in the process of bone matrix resorption rather than demineralization, resulting in higher demineralization and abnormal material deposition on the bone surface and at the cement lines. Furthermore, evidence of active osteoclastic bone resorption with a brush border formation at the bone involved in the inflammatory lesion in this case suggests that the osteoclastic malfunction is influenced and recovered by a microenvironment such as inflammatory cytokines. ( info) |
14/238. Osteopetrorickets: case report. We report the case of a baby girl who presented with rickets at 3 months. At the age of 5 months she was readmitted because of nystagmus and a diagnosis of osteopetrosis was made on the basis of clinical and radiological findings. rickets is a paradoxical feature of osteopetrosis resulting from inability to maintain a normal calcium-phosphorus balance. In our patient the onset of rickets before other symptoms of osteopetrosis suggests a primary defect. Conclusion: It is possible that patients with osteopetrosis and rickets (osteopetrorickets) represent a different mutation like the osteopetrosis mouse, which is the only animal mutation with rickets. ( info) |
15/238. Reversal of optic canal stenosis in osteopetrosis after bone marrow transplant. PURPOSE: To describe a patient with infantile osteopetrosis and optic atrophy secondary to optic canal stenosis who demonstrated optic canal enlargement after bone marrow transplant. methods: Case report. A 3-month-old infant with infantile "malignant" osteopetrosis underwent ophthalmic examination, including visual evoked potentials, electroretinogram, and computed tomography (CT). Bone marrow transplant was performed at 8 months of age. RESULTS: Examination revealed visual loss and optic atrophy, left eye greater than right eye, secondary to optic canal stenosis. Flash visual evoked potentials revealed a normal waveform in both eyes with increased latency in the left eye. Electroretinogram was normal in both eyes. CT after bone marrow transplant showed enlargement of the optic canals. Vision remains stable 43 months after bone marrow transplant. CONCLUSIONS: Bone marrow transplant in infantile osteopetrosis may be followed by reversal of optic canal stenosis and preservation of vision. ( info) |
| Visual loss with optic atrophy is common in osteopetrosis. The efficacy of optic nerve decompression in patients with osteopetrosis is still controversial. The purpose of this study is to report that visual deterioration in osteopetrosis can be completely reversed by early optic nerve decompression. An 8-year-old female patient with osteopetrosis was found to have reduced visual acuity on routine ophthalmologic examination. Extensive optic nerve decompression was performed. It not only included unroofing the optic canal, but also drilling away bone on both sidewalls of the optic nerve. Both optic nerves were decompressed during the same surgical procedure. Progressive loss of vision associated with osteopetrosis can be prevented by optic nerve decompression in the early stage of visual deterioration. When managing patients with osteopetrosis, the importance of careful and regular assessment of visual function should be stressed. ( info) |
17/238. Middle cerebral arterial occlusion in a child with osteopetrosis major. osteopetrosis major (infantile autosomal recessive type) usually presents with pathological fractures, bone marrow failure and some neurological deficits due to remodelling defect of the bone and narrowed bonny channel of the blood supply. Herein we present a case of osteopetrosis major with neurological deficits not attributed to the narrowed carotid channel of the petrous bone, but due to middle cerebral arterial occlusion 2 cm distal to narrowed channel. ( info) |
18/238. Asynchronous asymmetric form of heterogeneous osteopetrosis: initial case expanded and a new case. We have discovered additional serial radiographs and clinical information on the initial case of "regional osteopetrosis tarda" that has been included in several editions of Caffey's Pediatric X-Ray Diagnosis. A definite second case was found after a search of radiology teaching files of other selected medical centers and the International Skeletal Dysplasia Registry. Analysis of the sequential unusual radiographic findings of the initial case and the equivalent compelling findings of the second case justifies renewed attention to an asynchronous asymmetric form of heterogeneous osteopetrosis. ( info) |
19/238. Pyknodysostosis--a report of two cases with a brief review of the literature. Pyknodysostosis is a rare sclerosing bone disorder that has an autosomal dominant trait. It is characterized by short stature, brachycephaly, short and stubby fingers, open cranial sutures and fontanelle, and diffuse osteosclerosis, where multiple fractures of long bones and osteomyelitis of the jaw are frequent complications. We present a report of two cases of pyknodysostosis with evidence of long bone fractures and chronic suppurative osteomyelitis of the jaws in one of the cases. Some of the specific oral and radiological findings that are consistent with pyknodysostosis are reported, along with a brief review of the literature. ( info) |
20/238. prenatal diagnosis of malignant osteopetrosis in Bedouin families by linkage analysis. Autosomal recessive malignant osteopetrosis (MOP) is a lethal disease, unless bone marrow is successfully transplanted. Yet a donor may not always be available, and even when there is one transplantation results are far from optimal. The difficulty in obtaining conclusive results by sonographic and X-ray evaluation of the fetus makes prenatal molecular diagnosis highly desirable. Subsequent to the chromosomal localization of the MOP gene in Arab-Bedouin families from the Negev region in israel, linkage analysis was used for the prenatal diagnosis of this disease in Bedouin families at risk. Twelve cases were diagnosed, three fetuses were found to be affected, and one of the pregnancies was terminated. The other two pregnancies continued to term and the diagnosis of osteopetrosis was confirmed by X-ray immediately after birth. This is the first report on prenatal diagnosis of autosomal recessive osteopetrosis by linkage analysis. ( info) |