Peaks and tails: Evaluation of irregularities in capillary serum protein electrophoresis.

The increased analytical sensitivity of capillary electrophoresis detects additional irregularities that are suspicious for a monoclonal component. This is most noticeable in the beta-1-, beta-2- and gamma-globulin fractions. The causes of non-monoclonal irregularities are manifold, but are rarely reported back to the ordering physician. This article reviews the basic concepts to correctly identify irregularities, monoclonal and oligoclonal peaks by capillary electrophoresis. It then focuses on detecting and reporting typical non-monoclonal irregularities according to their electrophoresis fractions as well as their possible clinical implications.

Neurofilament heavy chain in CSF correlates with relapses and disability in multiple sclerosis.

OBJECTIVE: Neurodegeneration is now accepted as a pathologic hallmark of multiple sclerosis (MS). We sought to discover whether CSF levels of neurofilament heavy chain protein (NfH(SMI35)) correlate with disability, disease activity, or specific stages of MS. METHODS: An electrochemiluminescence immunoassay was used to retrospectively measure NfH(SMI35) in CSF of patients with clinically isolated syndrome (CIS) (n = 63), relapsing-remitting multiple sclerosis (RRMS) (n = 39), secondary progressive multiple sclerosis (SPMS) (n = 25), primary progressive multiple sclerosis (PPMS) (n = 23), or controls (n = 73). Cell count and CSF levels of immunoglobulin and albumin were also measured. RESULTS: CSF levels of NfH(SMI35) increased with age in controls (r(s) = 0.50, p < 0.0001) and CIS (r(s) = 0.50, p < 0.0001); this effect was less pronounced in RRMS (r(s) = 0.35, p = 0.027) and absent in SPMS/PPMS. After age correction, NfH(SMI35) levels were found to be higher in all disease stages compared to control. Relapses were associated with higher CSF NfH(SMI35) values compared with stable disease. NfH(SMI35) levels correlated with EDSS scores in patients with CIS and RRMS (r(s) = 0.33, p = 0.001), and during relapse (r(s) = 0.35, p = 0.01); the correlation was most prominent in RRMS during relapse (r(s) = 0.54, p = 0.01). This was not the case for any of the other CSF markers examined. CONCLUSIONS: Neuronal loss is a feature of aging, and the age-dependent increase of CSF NfH(SMI35) suggests that this loss accelerates over time. For MS, increased NfH(SMI35) levels reflect the superimposed presence of further neurodegenerative processes. Evaluation of NfH(SMI35) levels is likely to provide a useful surrogate for measuring the rate of neurodegeneration in MS. Furthermore, the dissociation of NfH(SMI35) levels with biomarkers of inflammation suggests that the mechanisms responsible for their production are at least partly independent.

[Cerebrospinal fluid-based diagnostics of CT-negative subarachnoid haemorrhage]. / Liquordiagnostik bei CT-negativer Subarachnoidalblutung.

The diagnostic investigation of CT-negative subarachnoid haemorrhage (SAH) is a particular challenge in clinical neurology. Cerebrospinal fluid (CSF) analysis via lumbar puncture is the method of choice. The diagnosis of SAH in CSF is based on a bloody or xanthochromic discoloration of the CSF as well as on findings in non-automated CSF cytology including the detection of erythrophages and siderophages. The automated determination of CSF ferritin concentrations or spectrophotometric detection of xanthochromia may contribute to the diagnosis but are only useful with regard to the overall clinical picture. Generally, the knowledge of the time flow of CSF changes associated with SAH is essential for a correct interpretation of CSF findings.

Increased levels of inflammatory chemokines in amyotrophic lateral sclerosis.

BACKGROUND AND PURPOSE: Amyotrophic lateral sclerosis (ALS) is classically assumed to be a neurodegenerative disorder. Inflammation has been observed in CNS tissue in ALS patients. We investigated the expression and prognostic relevance of proinflammatory chemokines in ALS. METHODS: We analyzed nine chemokines, eotaxin, eotaxin-3, IL-8, IP-10, MCP-1, MCP-4, macrophage derived chemokine (MDC), macrophage inflammatory protein-1beta (MIP-1beta), and serum thymus and activation- regulated chemokine (TARC) in serum and cerebrospinal fluid (CSF) of 20 ALS- and 20 non-inflammatory neurological disease (NIND)-patients. RESULTS: MCP-1 and IL-8 levels in CSF in ALS were significantly higher than in NIND (1304 pg/ml vs. 1055 pg/ml, P = 0.013 and 22.7 pg/ml vs. 18.6 pg/ml, P = 0.035). The expression of MCP-1 and IL-8 were higher in CSF than in serum (P < 0.001). There was a trend towards higher MCP-1 CSF levels in ALS patients with shorter time between first symptoms and diagnosis (r = -0.407; P = 0.075). CONCLUSIONS: We confirmed previous findings of increased MCP-1 levels in CSF of ALS patients. Furthermore, increased levels of IL-8 in CSF suggest a stimulation of a proinflammatory cytokine cascade after microglia activation. We found a tendency for higher MCP-1 values in patients with a shorter diagnostic delay, who are known to have also a shorter survival. This may suggest an association of higher MCP-1 levels with rapidly progressing disease.

[Standardized counting of particles in the urine: a comparison between flow cytometry, cell chamber counting and traditional sediment analysis]. / Standardisierte Partikelzählung im Urin: Ein Vergleich zwischen Durchfluss-Zytometrie, Zählkammer und traditionellem Urinsediment.

We compared the number of particles in the urine with flow cytometry and manual methods: cell chamber and standardised sediment analysis. The correlation (r) between the KOVA-cell chamber and the flow cytometer UF-100 was 0.966 for erythrocytes, 0.935 for leukocytes and 0.902 for squamous epithelial cells. Similar results were obtained by a standardised preparation of the sediment. Today, the estimation of the cell number in the sediment analysis is still common. The KOVA cell chamber system is a cheap alternative for microscopy, whereas automation with flow cytometry is only used for large laboratories. Reference values were established under optimal conditions (erythrocytes < 14/microliter, leukocytes < 16/microliter) with a cut-off of 20/microliter.

Urine analysis performed by flow cytometry: reference range determination and comparison to morphological findings, dipstick chemistry and bacterial culture results--a multicenter study.

AIM: To validate whether quantitative flow-cytometric analysis of particulate matter in urine would allow for accurate and rapid enumeration of red blood cells (RBC), leukocytes (WBC), squamous epithelial cells (EC), casts, and bacteria, a Sysmex UF-100 analyzer was tested in a multicenter study. MATERIAL AND METHODS: At first, reference values were established and found to be < 14 for RBC, < 16 for WBC, < 9 for EC, < 2 for casts and < 173 for bacteria, respectively (counts per microl; 97.5 percentile). Due to the wide use of dipstick and microscopic sediment analysis in routine urine diagnostics, comparative studies on 950 random urine samples were performed. Bacterial counting combined with WBC enumeration was further compared in 266 routine urinary microbiologic cultures. RESULTS: Good correlations were found comparing UF-100 results of RBC (r = 0.89), WBC (r = 0.94), and EC (r = 0.74) with Fuchs-Rosenthal Chamber (FRC) counts. However, some misclassification of casts (r = 0.32) could be observed. Correlations of UF-100 with dipstick and sediment testing was significant (p < 0.001), but the scatter of the latter two methods is too wide to consider them as quantitative methods. Promising results further revealed that the analyzer has a good negative predictive value (NPV) for microbiologically negative cultures, especially for cultures with bacterial counts of 10(5)/l (NPV = 95%). CONCLUSION: The analyzer is capable of providing rapid and reliable urine analysis of cellular particles avoiding the known imprecision of dipstick and sediment methodology. Thus, when used in an algorithm, combined with dipstick or quantitative urine chemistry analysis (for hemoglobin, esterase, protein, glucose, etc.), this analyzer might serve as a rapid and accurate screening tool in routine urine analysis, thereby reducing manual reviewing rate as well as the number of missed samples, compared to screening with dipstick alone.

[Diagnosis of cerebrospinal fluid leakage at the base of the skull]. / Diagnostik der Liquorrhoe bei Schädelbasisläsionen.

There are still several problems surrounding the diagnosis of cerebrospinal fluid leak. Currently the method of choice for cerebrospinal fluid detection is qualitative determination of beta-2-transferrin. Faster and more efficient methods (beta-trace) are under clinical investigation. The major problem is localisation of the site of leakage. Combination of several radiological methods increases the rate of correct diagnosis. In surgery the use of intrathecal sodium-fluorescein improves visualisation of the site of leakage and thus increases the chances of secure and stable closure of the cerebrospinal fluid fistula.

Interpreting complex urinary patterns with MDI LABLINK: a statistical evaluation.

The measurement of urinary marker proteins is not a generally accepted laboratory practice because the results are difficult to interpret. MDI-LABLINK is software for classifying patterns of specific urinary marker proteins. The interpretations are completely user definable thanks to a specific 'pattern definition database'. Our interpretation set is based on Hofmann and Guder's work in measuring and interpreting single urinary proteins. We include additional marker proteins in order to adapt Boesken's SDS-PAGE classification. During the last 3 years, 1905 patterns were fully differentiated and identically interpreted. Firstly, the samples were classified into three patterns: normal (25.8%), predominantly glomerular (27.2%, selective, unselective, mixed, and with additional tubular proteins) and predominantly tubular (36.9%, complete/incomplete form, with additional glomerular proteins); 8.9% showed postrenal proteinuria. Secondly, glomerular selectivity measured by using urinary transferrin/IgG ratio alone correlates well with the established SI index (the ratio between IgG and transferrin clearances). Thirdly, the creatinine concentration substantiates the validity of the sample. The quality of the preanalytical phase can be improved through the ongoing education of the medical staff. Finally, measurement of urinary albumin and alpha-1-microglobulin is mandatory where kidney disease is suspected, has to be ruled out, or requires close monitoring, even when the total protein concentration is normal.

Computer assisted interpretation of laboratory test data with 'MDI-LabLink'.

Physicians have to confront an enormous output of laboratory data. Normally, only a few experts manually perform the interpretation of highly specialised laboratory tests. PC Windows based 'MDI-LabLink' automates interpretation and expands traditional rule-based expert systems with flexibility and graphic illustrations of complex laboratory data. The laboratory can adjust the interpretation database to its specific needs, maintaining full control over program output. The structured input that 'MDI-LabLink' requires, supports dynamic test scheduling. It can be used to train personnel in the interpretation of laboratory test results. The program provides the clinician with a report that visualises the defect of the evaluated organ system with bitmap pictures and 3-dimensional graphics. Patient follow-ups present in tabular and graphical form. Changes in the severity of the pathobiochemical defect, induced, for example, by therapy, are monitored automatically. Applications available include interpretations of isoenzyme patterns, diagnosis of urinary proteinuria and cerebrospinal fluid analysis.

Bone metabolism before and after irradiation with ultraviolet light.

The beneficial effects of ultraviolet light on cutaneous vitamin D synthesis, calcium metabolism, and bone formation are well known. Regarding the increasing fear of side effects from ultraviolet B (UV-B), lamps with less energy in the UV-B range have been developed. Two spectra with differences in the emission of UV-B have therefore been evaluated for their influence on calcium metabolism. A group of 24 healthy male volunteers was subdivided into two treatment groups. Group 1 was exposed to lamps with higher energy of total UV-B but less energy at the wavelengths below 300 nm than the lamps used in group 2. All subjects were irradiated ten times within 12 days. Exposure time was 3 min in the first session and time of exposure was increased by 10% in every following irradiation (suberythematous doses only). Before the first irradiation, 3 days after the last exposure, and after 4 more weeks, the serum parameters of bone metabolism were determined by standard laboratory methods. Significantly increased levels of 25-hydroxyvitamin D3 were found in both groups. There was only a slight increase of 1,25-dihydroxyvitamin D3. Parathyroid hormone decreased significantly in group 2 only. The data would suggest beneficial effects on bone metabolism for both regimens. The observed effects were more pronounced when shorter wavelengths (group 2) were applied, although the total energy of UV-B was lower in these lamps.

[Cholesterol--a marker for multiple risk factors? A comparison between coronary disease and coronary health]. / Cholesterin--ein Marker für multiple Risikofaktoren? Ein Vergleich zwischen Koronarkranken und -gesunden.

Comparison was made in a cross-sectional study between 658 patients in whom coronary arteriography had shown (n = 304) or excluded coronary artery disease (CHD) (n = 354) and a clinically healthy group as controls (n = 1658), to assess possible risk factors. Patients aged 31-40 years with CHD had the highest total cholesterol levels (286 +/- 43 mg/dl) and the highest number of risk factors (3.6 +/- 0.9) compared to patients without CHD of the same age (204 +/- 30 mg/dl; 2.0 +/- 0.5) and healthy controls (216 +/- 45 mg/dl; 1.7 +/- 0.5) (P less than 0.001). In older patients with CHD, total cholesterol levels were lower (age group 61-70 years: 231 +/- 49 mg/dl), reaching about the same level as that of patients without CHD (232 +/- 54 mg/dl) or healthy controls of the same age (228 +/- 55 mg/dl). Furthermore, it was demonstrated that increased total cholesterol concentration can indicate the presence of other risk factors. It would thus appear that the level of total cholesterol in patients with CHD is decisively influenced by age and the presence of other risk factors.

Markers for HIV-disease progression in untreated patients and patients receiving AZT: evaluation of viral activity, AZT resistance, serum cholesterol, beta 2-microglobulin, CD4+ cell counts, and HIV antigen.

In order to find parameters which allow the assessment of the clinical state of HIV patients with or without antiviral therapy, viral cultures on lymphocytes and monocytes/macrophages, CD4-cell counts, HIV antigen, beta 2-microglobulin and serum cholesterol were evaluated for their predictive value. As had been shown previously for lymphocytes, the efficiency of viral isolation on macrophages also depends on the disease stage (CDC) of the patients and thus has a high predictive value. A multivariant discriminant analysis showed that the combination of beta 2-microglobulin, viral antigen, CD4+ cell count and HDL cholesterol predicted the outcome of viral cultures with 80% accuracy. While viral antigen, CD4+ cell counts and beta 2-microglobulin had been known, HDL cholesterol deserves further evaluation as prognostic parameter. The analysis of HIV derived from patients with AZT showed a 20-200-fold in vitro drug resistance after seven to 24 months of therapy. DNA sequence determination of such strains isolated from AZT patients over time showed only two of the amino acid exchanges described in the literature for resistant strains and an additional Val60-Ile transition after 32 months of therapy.