Improved assay protocol for measurement of ammonia on the Roche Cobas 8000 automated platform.

INTRODUCTION: Ammonia is a metabolite of protein catabolism that, when elevated, may be toxic for tissues, especially for the central nervous system. Elevated ammonia in blood is an indicator and a prognostic factor for hepatic and kidney disease or inherited metabolic disorders in nitrogen metabolism. The accuracy of ammonia determination is influenced by sampling condition, handling, storage and assay itself. Our and other laboratories have been experiencing high frequencies sample error flags while measuring ammonia with glutamate dehydrogenase method on Roche Cobas 8000 platform. To reduce the number of error flags we adapted Roche NH3L protocol by incorporation of an additional onboard routine step for sample pre-dilution. MATERIAL AND METHODS: The AMC NH3L is an adaptation of Roche protocol that uses four fold pre-dilution of the sample in the rerun prior to the analysis. It was assessed for 1.occurrence of absorbance error flags, 2.precision, 3.correlation with Roche method and 4.interference by hemolysis, icterus and lipemia. RESULTS: The AMC NH3L adaptation demonstrates acceptable within-run and total precision. Comparison studies show no differences between the Roche rerun application and AMC NH3L adaptation. The AMC NH3L adaptation solves 78% of absorbance errors and for samples with high ammonia concentration is less affected by interferences from icterus and hemolysis than the Roche rerun application. CONCLUSION: The AMC NH3L adaptation is less prone to instrument error flags and for samples with high ammonia concentration, is more robust to endogenous interferences. The AMC NH3L adaptation is viable alternative to the Roche protocol for the ammonia measurement.

Concomitant HIV infection in newly diagnosed multiple myeloma patients is hard to recognise and should be tested for routinely in areas of high endemicity.

BACKGROUND: Over the past three decades much has changed in the treatment and outcomes of patients suffering concurrently from both multiple myeloma (MM) and HIV. While the prevalence of MM appears to be higher in HIV-positive individuals than in those who are uninfected, early recognition of patients suffering from both diseases is difficult and little information is available on their demographics and clinical presentation. OBJECTIVE: To compare the presenting features of HIV-positive patients diagnosed with MM with those of HIV-negative patients. METHODS: A single-centre, retrospective cohort study included 16 HIV-positive and 73 HIV-negative patients diagnosed with MM, in order to compare variables related to the clinical presentation of both conditions. RESULTS: HIV-positive patients presented with MM at a significantly younger age, and had fewer osteolytic lesions, less renal impairment and lower neutrophil counts. Disease stage, gender, pathological fractures, bone marrow plasmacytosis, plasmacytomas and lymphocyte counts were comparable, emphasising the difficulty of identifying these patients. The HIV-positive patients had relatively high CD4 counts and a low prevalence of abnormal Freelite kappa/lambda ratios. All HIV-positive patients presented with paraproteins of the immunoglobulin G (IgG) type, implying a possible relationship between MM and an IgG response to HIV antigens. CONCLUSIONS: On the basis of our findings and literature on the treatment of both diseases, we suggest that HIV be tested for routinely in younger MM patients, especially in areas with a high prevalence of HIV. The integration of our results into the sparse knowledge on the role of HIV infection-related MM provides possible new insights into the interaction between these diseases.

Concomitant HIV infection in newly diagnosed multiple myeloma patients is hard to recognise and should be tested for routinely in areas of high endemicity

Background. Over the past three decades much has changed in the treatment and outcomes of patients suffering concurrently from both multiple myeloma (MM) and HIV. While the prevalence of MM appears to be higher in HIV-positive individuals than in those who are uninfected, early recognition of patients suffering from both diseases is difficult and little information is available on their demographics and clinical presentation.Objective. To compare the presenting features of HIV-positive patients diagnosed with MM with those of HIV-negative patients.Methods. A single-centre, retrospective cohort study included 16 HIV-positive and 73 HIV-negative patients diagnosed with MM, in order to compare variables related to the clinical presentation of both conditions.Results. HIV-positive patients presented with MM at a significantly younger age, and had fewer osteolytic lesions, less renal impairment and lower neutrophil counts. Disease stage, gender, pathological fractures, bone marrow plasmacytosis, plasmacytomas and lymphocyte counts were comparable, emphasising the difficulty of identifying these patients. The HIV-positive patients had relatively high CD4 counts and a low prevalence of abnormal Freelite kappa/lambda ratios. All HIV-positive patients presented with paraproteins of the immunoglobulin G (IgG) type, implying a possible relationship between MM and an IgG response to HIV antigens.Conclusions. On the basis of our findings and literature on the treatment of both diseases, we suggest that HIV be tested for routinely in younger MM patients, especially in areas with a high prevalence of HIV. The integration of our results into the sparse knowledge on the role of HIV infection-related MM provides possible new insights into the interaction between these diseases

Concomitant HIV infection in newly diagnosed multiple myeloma patients is hard to recognise and should be tested for routinely in areas of high endemicity

Background. Over the past three decades much has changed in the treatment and outcomes of patients suffering concurrently from both multiple myeloma (MM) and HIV. While the prevalence of MM appears to be higher in HIV-positive individuals than in those who are uninfected, early recognition of patients suffering from both diseases is difficult and little information is available on their demographics and clinical presentation.Objective. To compare the presenting features of HIV-positive patients diagnosed with MM with those of HIV-negative patients.Methods. A single-centre, retrospective cohort study included 16 HIV-positive and 73 HIV-negative patients diagnosed with MM, in order to compare variables related to the clinical presentation of both conditions.Results. HIV-positive patients presented with MM at a significantly younger age, and had fewer osteolytic lesions, less renal impairment and lower neutrophil counts. Disease stage, gender, pathological fractures, bone marrow plasmacytosis, plasmacytomas and lymphocyte counts were comparable, emphasising the difficulty of identifying these patients. The HIV-positive patients had relatively high CD4 counts and a low prevalence of abnormal Freelite kappa/lambda ratios. All HIV-positive patients presented with paraproteins of the immunoglobulin G (IgG) type, implying a possible relationship between MM and an IgG response to HIV antigens.Conclusions. On the basis of our findings and literature on the treatment of both diseases, we suggest that HIV be tested for routinely in younger MM patients, especially in areas with a high prevalence of HIV. The integration of our results into the sparse knowledge on the role of HIV infection-related MM provides possible new insights into the interaction between these diseases

[Breast self-examination also valuable in women participating in a screening programme]. / Borstzelfonderzoek ook van waarde bij vrouwen die participeren in een screeningsprogramma.

OBJECTIVE: To evaluate the different methods of detection of breast cancer in women who at time of diagnosis underwent screening mammographies as participants in the Dutch National Breast Cancer Screening Programme (BOB group), and in women who participated in an intensive screening programme for a familial or genetic predisposition to breast cancer (FAM group). DESIGN: Partly retrospective, partly prospective, descriptive. METHOD: All patients who had surgery for invasive breast cancer at the VU University Medical Center, Amsterdam, the Netherlands, from 1 January 1995 to 30 June 2006 and who were participating in one of the abovementioned screening programmes at the time of diagnosis, were included. Data concerning the palpability of the tumour at time of diagnosis and the diagnostic method that first led to breast cancer being diagnosed, were collected. RESULTS: The BOB group consisted of 397 women with invasive carcinoma of which 57% (227/397) tumours were palpable at the time of diagnosis. The majority (64%; 146/227) of the palpable tumours were discovered by breast self-examination as an interval carcinoma. 31% (71/227) were detected by screening mammography and were also palpable. During the same period, 490 women participated in the high risk screening programme; in this FAM group, 23 invasive tumours were detected. A total of 61% (14/23) of these lesions were found during breast self-examination; 7 lesions (30%) were found by imaging. CONCLUSION: In women who participated in one of the 2 screening programmes, the majority of invasive breast cancers were palpable and more than half were detected by breast self-examination. Performing breast self-examination on a regular basis may contribute to early detection of breast cancer. Therefore, the teaching of breast self-examination to women should be encouraged, even if they are participating in a breast cancer screening programme.

IgA nephropathy in psoriasis.

IgA nephropathy (IGAN) was first described by Berger and Hinglais in 1968. It is now the most common glomerular disease worldwide. IGAN has been associated with several diseases. Its association with psoriasis has been rarely described. We report a case of IGAN with crescentic changes, associated with psoriasis vulgaris. We review the literature on the association of IGAN with psoriasis and discuss the likely pathogenetic linkage.

Demonstration by EPR spectroscopy of the functional role of iron in soybean lipoxygenase-1.

1. The EPR spectrum at 15 degrees K of soybean lipoxygenase-1 in borate buffer pH 9.0 has been studied in relation to the presence of substrate (linoleic acid), product (13-L-hydroperoxylinoleic acid) and oxygen. 2. The addition of 13-L-hydroperoxylinoleic acid to lipoxygenase-1 at pH 9.0 gives rise to the appearance of EPR lines at g equals 7.5, 6.2, 5.9 and 2.0, and an increased signal at g equals 4.3. 3. In view of the effect of the end product on both the kinetic lag period of the aerobic reaction and the fluorescence of the enzyme, it is concluded that 13-L-hydroperoxylinoleic acid is required for the activation of soybean lipoxygenase-1. Thus it is proposed that the enzyme with iron in the ferric state is the active species. 4. A reaction scheme is presented in which the enzyme alternatingly exists in the ferric and ferrous states for both the aerobic and anaerobic reaction.