Hematopoietic stem cell engraftment and seeding permits multi-lymphoid chimerism in vascularized bone marrow transplants

Vascularized bone marrow transplantation (VBMT) across a MHC barrier under a 7-day alphabeta-TCR mAb and CsA protocol facilitated multiple hematolymphoid chimerism via trafficking of the immature (CD90) bone marrow cells (BMC) between donor and recipient compartments. Early engraftment of donor BMC [BN(RT1(n))] into the recipient BM compartment [LEW(RT1(l))] was achieved at 1 week posttransplant and this was associated with active hematopoiesis within allografted bone and correlated with high chimerism in the hematolymphoid organs. Two-way trafficking between donor and recipient BM compartments was confirmed by the presence of recipient MHC class I cells (RT1(l)) within the allografted bone up to 3 weeks posttransplant. At 10 weeks posttransplant, decline of BMC viability in allografted bone corresponded with bone fibrosis and lack of hematopoiesis. In contrast, active hematopoiesis was present in the recipient bone as evidenced by the presence of donor-specific immature (CD90/RT1(n)) cells, which correlated with chimerism maintenance. Clonogenic activity of donor-origin cells (RT1(n)) engrafted into the host BM compartment was confirmed by colony-forming units (CFU) assay. These results confirm that hematolymphoid chimerism is developed early post-VBMT by T-cell lineage and despite allografted bone fibrosis chimerism maintenance is supported by B-cell linage and active hematopoiesis of donor-origin cells in the host BM compartment.

Technetium-99m 2-methoxy-isobutyl-isonitrile uptake scintigraphy in detection of the bone marrow infiltration in multiple myeloma: correlation with MRI and other prognostic factors

Whole-body scintigraphy with Technetium-99m 2-methoxy-isobutyl-isonitrile ((99m)Tc-MIBI) has been proposed as a useful method for demonstrating the areas of active bone marrow infiltration in multiple myeloma (MM). In this study, we compared the (99m)Tc-MIBI scan with magnetic resonance imaging (MRI), skeletal X-ray survey, and biochemical markers of disease activity in MM to determine its potential in predicting the extension of the disease. Twenty-four myeloma patients had undergone to the (99m)Tc-MIBI scan. Only two patients showed negative results in the (99m)Tc-MIBI scan; one had clinically active disease, and the other was on remission. MRI was performed to 18 clinically active patients, and 16 of them showed positive myelomatous bone marrow involvement. No significant difference was found between the (99m)Tc-MIBI scan and MRI in predicting the extension of bone marrow infiltration in MM (p = 0.11). (99m)Tc-MIBI scores were correlated with bone marrow neoplastic plasma cell ratio (p = 0.005), serum paraprotein level (p < 0.001), serum lactate dehydrogenase (p = 0.031), and beta-2 microglobulin (p = 0.045). The (99m)Tc-MIBI scan showed disease activity better than the skeletal X-ray survey (x2 = 5.299, p = 0.021). A significant decrease was found in posttreatment (99m)Tc-MIBI scores of the patients with positive overall response (p = 0.016). The (99m)Tc-MIBI scan is a noninvasive test that can show the extension of the disease in MM. It seems that the (99m)Tc-MIBI scan and MRI show extension and intensity of the myelomatous bone marrow infiltration equally well. The (99m)Tc-MIBI scan can be an alternative to MRI when it is not available or if there is any limitations for its usage.

Donor–origin cell engraftment after intraosseous or intravenous bone marrow transplantation in a rat model

We compared the effects of intraosseous BMT with those of standard i.v. BMT on the efficacy on donor-cell engraftment into the BM and lymphoid organs across an MHC barrier in rats. Twenty-four intraosseous and 24 i.v. BMTs were performed from 48 ACI (RT1(a)) donors to 48 Lewis (RT1(l)) recipients. Each transplant group received either intraosseous or i.v. BMT. Groups I and II served as controls without immunosuppression (n=16); groups III and IV received cyclosporine monotherapy (n=16); and V and VI received alphabeta-TCR monoclonal antibody and cyclosporine A (alphabeta-TCR/CsA) for 7 days (n=16). In each group, four rats received 35 x 10(6) transplanted bone marrow cells (BMCs) and four received 70 x 10(6) cells. All animals survived without GVHD. Mean (+/-s.d.) donor-cell engraftment into BM of recipients after intraosseous BMT was 7.9% (+/-1.3%) in recipients receiving alphabeta-TCR-CsA and 70 x 10(6) BMCs, and 4.2% (+/-1.4%) in recipients after i.v. transplantation. The seeding efficacy of donor cells into lymphoid tissue was greater after intraosseous BMT and alphabeta-TCR-CsA than after standard i.v. transplantation. In our model, intraosseous BMT facilitated donor-cell engraftment under short-term immunodepletive alphabeta-TCR/CsA protocol, which resulted in a temporary state of immune unresponsiveness.

Fluoroscopically guided endoluminal balloon dilation of oesophageal stricture due to dystrophic epidermolysis bullosa in two sisters

Dystrophic epidermolysis bullosa is an inherited disorder with frequent oesophageal stricture formation. There is no satisfactory medical treatment of dysphagia however; endoluminal balloon dilation is a novel method with satisfactory results. Intrafamilial cases of dystrophic epidermolysis bullosa manifest variable clinical presentations. We report two sisters with dystrophic epidermolysis bullosa simultaneously presenting with dysphagia. Fluoroscopically guided endoscopic balloon dilation revealed almost complete resolution of dysphagia in both patients. Our cases represented a striking similarity in their clinical picture and response to treatment. Balloon dilation in these cases is a safe and effective approach.

The diagnosis of osteomyelitis of the foot in diabetes: microbiological examination vs. magnetic resonance imaging and labelled leucocyte scanning

AIMS

Foot infections and their sequelae are among the most common and severe complications of diabetes mellitus. As diabetic patients with foot infections develop osteomyelitis and may progress to amputation, early diagnosis of osteomyelitis is critical.

METHODS

We compared the diagnostic values of labelled leucocyte scanning with Tc(99)m, magnetic resonance imaging (MRI) and microbiological examination of bone tissue specimens with histopathology, the definitive diagnostic procedure. Thirty-one diabetic patients with foot lesions were enrolled in the study and histopathological examination was performed in all. Patients had clinically suspected foot lesions of > or = grade 3 according to the classification of Wagner.

RESULTS

Bone specimens were obtained for histopathological examination. Microbiology had a sensitivity of 92% and specificity of 60%. Labelled leucocyte scanning had a sensitivity of 91%, specificity of 67%, and MRI a sensitivity of 78%, specificity of 60%.

CONCLUSIONS

Microbiological examination may be as useful as and less costly than other diagnostic procedures and is the only method which can guide the choice of antibiotic therapy.

Epidemiology and outcome of sepsis in a tertiary-care hospital in a developing country

Sepsis continues to have a substantial mortality and morbidity despite advances in the diagnosis and management of this condition. We retrospectively analysed hospital charts of patients diagnosed to have sepsis between January 2002 and June 2003. Demographic characteristics of patients, microbiological findings and predictors of survival were evaluated. Sixty-nine sepsis episodes that occurred in 63 patients were analysed. The most common underlying diseases were hypertension, malignancies and diabetes mellitus. Renal insufficiency, respiratory distress and disseminated intravascular coagulation developed in 52.2, 30.4 and 30.4% of the episodes respectively; 47.7% of the blood cultures yielded an organism. Gram-negative bacteria were the predominant microorganisms (65.9%). Fifty-five patients (87.3%) died. Mechanical ventilation and underlying renal disease were significant determinants of mortality. In conclusion, Gram-negative bacteria remain the major pathogens in sepsis. The mortality remains very high, and a change in the clinical approach to the septic patient should be employed to improve the outcome.

Rapid detection of antibacterial resistance in emerging Gram-positive cocci

Effective infection control efforts obviously depend on the performance of the laboratory to detect emerging resistant pathogens accurately and confirm resistance patterns by additional methods to conventional or automated systems. Conventional methods still remain the predominant approaches for detection and identification of bacteria and resistance patterns. However, the estimated time for conventional tests to detect resistance is at least 24-48 h for methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and other epidemiologically important pathogens. Most of the tests used for rapid detection require bacterial growth in culture. There is an important clinical need for rapid detection of bacteria directly from patient samples. Rapid methods based on immunological or molecular technologies have contributed significantly. Molecular assays for several resistance markers are reliable, such as for mecA in staphylococci and vanA in enterococci. However, for other resistance markers, there is a lack of field testing. Cost-effectiveness of rapid detection of antibacterial resistance is another concern. Molecular assays would be useful for tertiary hospitals considering the investment costs and requirement of expert laboratory staff. For smaller centres, rapid tests based on immunological techniques may be a better choice.

Fibrinogen storage disease without hypofibrinogenemia associated with estrogen therapy

BACKGROUND

Cytoplasmic inclusion bodies within hepatocytes may have different etiologies, including the Endoplasmic Reticulum Storage Diseases (ERSDs). ERSD is a pathological condition characterized by abnormal accumulation of proteins destined for secretion in the endoplasmic reticulum of hepatocytes; it may be congenital (primary) or acquired (secondary). Fibrinogen storage disease is a form of ERSD.

CASE PRESENTATION

We present a case of fibrinogen storage disease secondary to estrogen replacement therapy. Its causal relationship to the drug is shown by histological, immunohistochemical and ultrastructural studies of paired liver biopsies obtained during and after the drug therapy.

CONCLUSION

The liver biopsies of patients with idiopathic liver enzyme abnormalities should be carefully evaluated for cytoplasmic inclusion bodies and, although rare, fibrinogen deposits.

Infection with Fasciola hepatica

Fascioliasis, caused by the liver fluke Fasciola hepatica, is an infection that occurs worldwide, although humans are accidental hosts. F. hepatica infection comprises two stages, hepatic and biliary, with different signs and symptoms. Stool examination and ELISA can be used for the initial diagnosis. Radiographic techniques, such as computerised tomography and ultrasonography, as well as magnetic resonance imaging, are used widely for confirmation and follow-up of the disease. Invasive techniques, such as percutaneous cholangiography, endoscopic retrograde cholangiography and liver biopsy, may aid in the diagnosis but are not essential. Triclabendazole is recommended as the first-line agent for the treatment of F. hepatica infection, with bithionol as an alternative.