Tumors of the Osseous Spine

Recent advances in molecular biology with the development of novel therapeutic agents, as well as fundamental understanding of the mechanisms of bone metastases have greatly altered the therapeutic options in patients with spine tumors. Improvements in spine instrumentation as well as the development of recombinant Bone Morphogenetic Protein for spine reconstruction and fusion offers promising hope for curative strategies in selected patients. A clearer application of the fundamentals of surgical oncology applied to spine tumors should result in a greater proportion of patients undergoing surgically appropriate en bloc resections for spine tumors. Finally, the superiority of surgery over external irradiation in the controlled clinical trial setting should greatly expand the pool of patients requiring surgery. In this review, we consider the recent advances in primary bone tumors including chordoma, sarcomas, multiple myeloma, as well as metastatic cancer to the spine.     

Genotype determines phenotype in experimental Lyme borreliosis

Borrelia burgdorferi sensu lato, the causative organism of Lyme borreliosis, is a heterogeneous group of spirochetes, consisting of at least three pathogenic species. To test the hypothesis that the genetic heterogeneity is the reason for the clinical differences, we investigated whether the experimental disease induced by European isolates is different from that induced by American isolates. Two American isolates of species B. burgdorferi sensu stricto were compared with three European isolates, two of species B. garinii, and one of species B. afzelii. The patterns of infection, immunity, and inflammation induced by the different species was distinctive. Inflammatory cells and levels of antibody in B. garinii- and B. afzelii-infected animals were lower than in B. burgdorferi s.s.-infected animals, whereas levels of spirochetal infection in the skin and nervous system were higher in the former group of animals. These data demonstrate that B. burgdorferi s.s. strains are more infective and inflammatory, whereas B. garinii and B. afzelii strains can survive the adaptive immune response to a greater degree and persist at greater numbers in the skin and nervous system. The results explain to a large extent the disparities between LNB in humans in the United States and Europe.     

DNA methylation profiles of lymphoid and hematopoietic malignancies.

PURPOSE: Aberrant methylation of the 5' gene promoter regions is an epigenetic phenomenon that is the major mechanism for silencing of tumor suppressor genes in many cancer types. The aims of our study were (a) to compare the methylation profiles of the major forms of hematological malignancies and (b) to determine the methylation profile of monoclonal gammopathy of undetermined significance (MGUS) and compare it with that of multiple myeloma (MM). EXPERIMENTAL DESIGN: We compared the aberrant promoter methylation profile of 14 known or suspected tumor suppressor genes in leukemias (n = 48), lymphomas (n = 42), and MMs (n = 40). We also examined the methylation profile of MGUS (n = 20), a premalignant plasma cell dyscrasia. The genes studied represent five of the six "hallmarks of cancer." RESULTS: Peripheral blood lymphocytes (n = 14) from healthy volunteers were negative for methylation of all genes, and methylation percentages in 41 nonmalignant tissues (peripheral blood mononuclear cells, bone marrows, and lymph nodes) from hematological patients were low (0-9%) for all 14 genes, confirming that methylation was tumor specific. Ten of the genes were methylated at frequencies of 29-68% in one or more tumor types, and the methylation indices (an indicator of overall methylation) varied from 0.25 to 0.34. With two exceptions, the methylation patterns of leukemias and lymphomas were similar. However, the pattern of MMs varied from the other tumor types for six genes. In general, the methylation pattern of MGUS was similar to that of MM, although the methylation frequencies were lower (the methylation index of MGUS was 0.15, and that of MM was 0.3). However, the methylation frequencies of six genes were significantly higher in MGUS than in control tissues. The relatively high frequencies of methylation in MGUS are consistent with it being a premalignant condition. CONCLUSIONS: The three major forms of lymphoid/hematopoietic malignancies show overlapping but individual patterns of methylation.     

Vascular rings: an important cause of persistent respiratory symptoms in infants and children

OBJECTIVE: To study the pattern of symptomatic vascular rings in infants and children with particular reference to clinical features, investigations and management. SETTING: Tertiary Care Paediatric Cardiology Division at the Royal Hospital, Muscat, Sultanate of Oman. DESIGN: Retrospective study. METHODS: Data on all patients aged less than 13 years diagnosed to have symptomatic vascular rings at the Royal Hospital, Muscat, Oman from 1992 to 2001 were retrieved from hospital records. RESULTS: Sixteen patients, 8 males and 8 females, aged 15 days to 36 months were identified, and included 12 with double aortic arch and 4 with right aortic arch, aberrant left subclavian artery and ligamentum arteriosum. Associated intracardiac defects were not found in any. Noisy breathing (7/16), stridor (6/16), respiratory distress (5/16) and recurrent respiratory infections (5/16) were the common modes of presentation. The duration from onset of symptoms to diagnosis ranged from 3 weeks to 24 months. Besides suggestive clinical features, the diagnosis was suspected from the chest radiograph (presence of right aortic arch) in 7 patients and from 2-Dimensional echocardiography and Doppler studies in 5 patients. Barium swallow studies, however, documented the abnormal esophageal indentation in all the 16 patients. Confirmatory imaging techniques included digital subtraction angiography in 7/16, cardiac catheterization and angiography in 5/16, and CT and MRI of the chest in 2 each. All 16 patients underwent successful surgical repair, and 13/16 became asymptomatic. 3 patients continued to suffer from occasional respiratory infections. CONCLUSIONS: A high index of clinical suspicion coupled with the use of barium oesophagraphy enabled early diagnosis in patients with symptomatic vascular rings, and surgical repair could be performed successfully in all patients.     

Keith Edwards score for diagnosis of tuberculosis

Objective : To evaluate the applicability of Keith Edwards scoring system for the diagnosis of childhood tuberculosis.Methods. One hundred and one children aged 2 months to 12 years who fulfilled the inclusion criteria were evaluated with Keith Edwards score. The diagnosis of tuberculosis by Keith Edwards score and the definitive reference were compared.Results. Among the 65 children diagnosed as having tuberculosis by the definitive reference, 59 had a Keith Edwards score of >7. Four children had a score of >7 but were not suffering from tuberculosis. The sensitivity and specificity of this score have been found to be 91% and 88% respectively.Conclusion. In select population with indicative clinical features, Keith Edwards score can be a definitive guideline for the diagnosis of childhood tuberculosis. However, more studies are required for the validation of this clinical score before it can be used as a definitive diagnostic reference standard for tuberculosis.     

Crescentic fibrillary glomerulonephritis associated with hepatitis C viral infection

Fibrillary glomerulonephritis (FGN) is a pathological diagnosis that is rarely associated with systemic disorders. In this case report, we describe a woman who presented with FGN of the crescentic type in association with hepatitis C viral infection. The existing literature on the association between these 2 disorders is reviewed, and postulated therapy is presented.