A distinct form of spondyloepimetaphyseal dysplasia with joint laxity (SEMDJL)-leptodactylic type: radiological characteristics in seven new patients.

OBJECTIVE: This study presents seven cases of a rare but distinctive form of spondyloepimetaphyseal dysplasia with joint laxity-leptodactylic or Hall type to emphasize the characteristic clinical and radiological findings. MATERIALS AND METHODS: A multiinstitutional retrospective review was performed on seven patients. The patient population consisted of one family with an affected mother and two siblings and four unrelated patients; there were one adult, aged 40 years, and six children, ranging in age from 3 to 12 years. The gender ratio of females to males was 5 to 2. We reviewed the clinical data and skeletal surveys and focused on radiographs of the pelvis, knees, hands, and spine. RESULTS: The outstanding clinical features were short stature, midface hypoplasia, and multiple dislocations and/or ligamentous laxity of the large joints, particularly at the knees with a genu valgum or varum deformity. Of seven patients, six patients showed normal intellect but one patient had mild mental retardation. The main radiological features included small, irregular epiphyses, metaphyseal irregularity with vertical striations that was a constant finding at the knees, constricted femoral necks, delayed ossification of the carpal bones, and slender metacarpals. Progressive thoracolumbar scoliosis was evident with aging; however, the vertebral bodies appeared normal in height or mild platyspondyly was noted. CONCLUSION: In view of the orthopedic management of multiple joint dislocations and ligamentous laxity of the large joints, awareness of this disease entity and diagnostic precision solely based on radiological findings is of importance, particularly as the disorder is currently more common than initially reported.

Steroid-dependent ACTH-produced thymic carcinoid: regulation of POMC gene expression by cortisol via methylation of its promoter region.

AIMS: Metyrapone causes a decrease in the serum cortisol level without affecting ACTH production in ectopic tumors. We report a case who presented with Cushing's syndrome due to an ectopic ACTH-producing thymic carcinoid. In the present case, it was demonstrated that metyrapone administration resulted in a significant decrease in the plasma ACTH and serum cortisol levels. We hypothesized that the steroid hormone may promote proopiomelanocortin (POMC) gene expression in the carcinoid cells. METHODS: An 11-year-old boy presented with Cushing's syndrome. Prior to the detection of a thymic tumor, metyrapone was administered to ameliorate the symptoms of Cushing's syndrome. Interestingly, plasma ACTH as well as serum cortisol levels immediately decreased after metyrapone administration. The levels of cortisol and ACTH were observed to be normal after complete surgical resection of the tumor. Biological characterization of the tumor cells was by in vitro analysis. RESULTS: Thein vitro culture of the tumor cells showed an increased expression of POMC in the presence of cortisol. A CpG methylation assay showed that the demethylation of the POMC promoter was induced by a steroid hormone. CONCLUSION: These findings suggest that the ectopic ACTH-producing tumor may partly be regulated by the elevated levels of cortisol.

A case of adolescent primary adrenal natural killer cell lymphoma.

Primary adrenal lymphoma is uncommon, and the majority cases of this disorder are found in elderly individuals. We describe a 17-year-old boy with persistent fever, hemophagocytic lymphohistiocytosis, and a bilateral tumor of the adrenal glands. The disease was progressive and did not respond to treatment such as immunosuppression therapy or plasma exchange. Postmortem analysis revealed nasal-type natural killer cell lymphoma in association with Epstein-Barr virus infection. To our knowledge, this case is the first of primary adrenal lymphoma with the natural killer cell phenotype to be reported. The characterization of this unusual case should be included in the differential diagnosis of adrenal gland tumors.

Dysregulation of transcriptions in primary granule constituents during myeloid proliferation and differentiation in patients with severe congenital neutropenia.

We examined the expression of granule constituent genes in myeloid progenitor cells during proliferation and differentiation in patients with severe congenital neutropenia (SCN). The heterozygous mutation of the neutrophil elastase gene was identified in two of four patients. The CD34+/granulocyte-colony stimulating factor receptor (G-CSFR)+ cells of SCN patients showed defective responsiveness to G-CSF in serum-deprived culture. The CD34+/G-CSFR+ cells expressed low levels of the granule constituent mRNAs. The transcription levels of primary granule enzyme genes in CD34+/G-CSFR+ cells were gradually enhanced and then decreased when cells were induced toward myeloid lineage with G-CSF in normal subjects. However, the primary up-regulation and the following down-regulation of these enzyme transcriptions were not clearly observed in SCN patients. No differences in expressions of the lactoferrin gene were seen between normal subjects and patients with SCN. We hypothesize that the abnormal regulation of the transcription in primary granule constituents might involve the defective proliferation and differentiation of myeloid cells in patients with SCN.

Defects of granulopoiesis in patients with severe congenital neutropenia.

To confirm the abnormalities of primitive myeloid progenitor cells in patients with severe congenital neutropenia (SCN), we studied their responsiveness to hematopoietic factors including granulocyte colony-stimulating factor (G-CSF). In all SCN patients studied no abnormalities of granulocyte colony-stimulating factor receptor (G-CSFR) gene were detected by polymerase chain reaction-single-strand conformation polymorphism analysis and sequence analysis. A flow cytometric analysis of bone marrow cells based on the expression of CD34, Kit receptor, and G-CSFR demonstrated a reduced frequency of CD34+/Kit+/G-CSFR+ cells in patients with SCN. The granulocyte/macrophage (GM)-colony formation of CD34+/Kit+/G-CSFR+ cells in patients was markedly decreased at all concentrations of G-CSF in serum-deprived semisolid culture. The responsiveness of CD34+/Kit+/G-CSFR+ cells in patients showed a reduced response to the combination of stem cell factor, the ligand for flk2/flt3, and interleukin-3 with or without G-CSF in serum-deprived semisolid and liquid suspension cultures. In contrast, no difference in the responsiveness of CD34+/Kit+/G-CSFR- cells was noted between SCN patients and normal subjects. The bone marrow cells from a patient who underwent bone marrow transplantation showed a restoration of both the reduced frequency and the decreased level of GM-colony formation of CD34+/Kit+/G-CSFR+ cells. These results demonstrate that the presence of qualitative and quantitative abnormalities of primitive myeloid progenitor cells expressing G-CSFR may play an important role in the impairment of granulopoiesis in patients with SCN.