Joris R. Delanghe

Lowered ω3 polyunsaturated fatty acids in serum phospholipids and cholesteryl esters of depressed patients

Depression is associated with a lowered degree of esterification of serum cholesterol, an increased C20:4omega6/C20:5omega3 ratio and decreases in omega3 fractions in fatty acids (FAs) or in the red blood cell membrane. The aims of the present study were to examine: (i) serum phospholipid and cholesteryl ester compositions of individual saturated fatty acids (SFAs), monounsaturated FAs (MUFAs) and polyunsaturated FAs (PUFAs) in major depressed patients vs. healthy volunteers; (ii) the relationships between the above FAs and lowered serum zinc (Zn), a marker of the inflammatory response in depression; and (iii) the effects of subchronic treatment with antidepressants on FAs in depression. The composition of the FAs was determined by means of thin layer chromatography in conjunction with gas chromatography. Lipid concentrations were assayed by enzymatic colorimetric methods. The oxidative potential index (OPI) of FAs was computed in 34 major depressed inpatients and 14 normal volunteers. Major depression was associated with: increased MUFA and C22:5omega3 proportions and increased C20:4omega6/C20:5omega3 and C22:5omega6/C22:6omega3 ratios; lower C22:4omega6, C20:5omega3 and C22:5omega3 fractions in phospholipids; lower C18:3omega3, C20:5omega3 and total (sigma)omega3 FAs, and higher C20:4omega6/C20:5omega3 and sigmaomega6/sigmaomega3 ratios in cholesteryl esters; lower serum concentrations of phospholipids and cholesteryl esters; and a decreased OPI. In depression, there were significant and positive correlations between serum Zn and C20:5omega3 and C22:6omega3 fractions in phospholipids; and significant inverse correlations between serum Zn and the sigmaomega6/sigmaomega3, C20:4omega6/C20:5omega3, and C22:5omega6/C22:6omega3 ratios in phospholipids. There was no significant effect of antidepressive treatment on any of the FAs. The results show that, in major depression, there is a deficiency of omega3 PUFAs and a compensatory increase in MUFAs and C22:5omega6 in phospholipids. The results suggest that: (i) there is an abnormal metabolism of omega3 PUFAs in depression; (ii) the FA alterations in depression are related to the inflammatory response in that illness; and (iii) the disorders may persist despite successful antidepressant treatment.

Cloning of 16S rRNA genes amplified from normal and disturbed vaginal microflora suggests a strong association between Atopobium vaginae, Gardnerella vaginalis and bacterial vaginosis

BackgroundThe pathogenesis of bacterial vaginosis remains largely elusive, although some microorganisms, including Gardnerella vaginalis, are suspected of playing a role in the etiology of this disorder. Recently culture-independent analysis of microbial ecosystems has proven its efficacy in characterizing the diversity of bacterial populations. Here, we report on the results obtained by combining culture and PCR-based methods to characterize the normal and disturbed vaginal microflora.ResultsA total of 150 vaginal swab samples from healthy women (115 pregnant and 35 non-pregnant) were categorized on the basis of Gram stain of direct smear as grade I (n = 112), grade II (n = 26), grade III (n = 9) or grade IV (n = 3). The composition of the vaginal microbial community of eight of these vaginal swabs (three grade I, two grade II and three grade III), all from non-pregnant women, were studied by culture and by cloning of the 16S rRNA genes obtained after direct amplification. Forty-six cultured isolates were identified by tDNA-PCR, 854 cloned 16S rRNA gene fragments were analysed of which 156 by sequencing, yielding a total of 38 species, including 9 presumptively novel species with at least five species that have not been isolated previously from vaginal samples. Interestingly, cloning revealed that Atopobium vaginae was abundant in four out of the five non-grade I specimens. Finally, species specific PCR for A. vaginae and Gardnerella vaginalis pointed to a statistically significant co-occurrence of both species in the bacterial vaginosis samples.ConclusionsAlthough historically the literature regarding bacterial vaginosis has largely focused on G. vaginalis in particular, several findings of this study – like the abundance of A. vaginae in disturbed vaginal microflora and the presence of several novel species – indicate that much is to be learned about the composition of the vaginal microflora and its relation to the etiology of BV.

Hemopexin: a review of biological aspects and the role in laboratory medicine.

BACKGROUND Hemopexin is a heme-binding plasma glycoprotein which, after haptoglobin, forms the second line of defense against hemoglobin-mediated oxidative damage during intravascular hemolysis. A decrease in plasma hemopexin concentration reflects a recent release of heme compounds in the extracellular compartment. Heme-hemopexin complexes are delivered to hepatocytes by receptor-mediated endocytosis after which hemopexin is recycled to the circulation. METHODS OF ANALYSIS Immunonephelometric and -turbidimetric hemopexin assays are available as more precise and rapid alternatives to the radial immunodiffusion technique. INTERPRETATIONS Hemopexin determinations are not subject to interference by in vitro hemolysis. Altered serum or plasma concentrations of hemopexin are found not only in hemolytic anemias but also in other conditions such as chronic neuromuscular diseases and acute intermittent porphyria. In laboratory medicine, while hemopexin determination in tandem with haptoglobin has potential applications in the assessment of intravascular hemolysis and allows for the monitoring of the severity of hemolysis after depletion of haptoglobin, its diagnostic utility is less clear in other pathological conditions. Further studies are necessary to fully establish the clinical significance of hemopexin determination.

Serum Vitamin C Concentration Is Low in Peripheral Arterial Disease and Is Associated With Inflammation and Severity of Atherosclerosis

BackgroundPeripheral arterial disease (PAD) is a severe atherosclerotic condition frequently accompanied by inflammation and oxidative stress. We hypothesized that vitamin C antioxidant levels might be low in PAD and are related to inflammation and disease severity. Methods and ResultsWe investigated vitamin C (l-ascorbic acid) levels in 85 PAD patients, 106 hypertensives without PAD, and 113 healthy subjects. Serum l-ascorbic acid concentrations were low among PAD patients (median, 27.8 &mgr;mol/L) despite comparable smoking status and dietary intake with the other groups (P <0.0001). Subclinical vitamin C deficiency (<11.4 &mgr;mol/L), confirmed by low serum alkaline phosphatase activity, was found in 14% of the PAD patients but not in the other groups. Serum C-reactive protein (CRP) concentrations were significantly higher in PAD patients (P <0.0001) and negatively correlated with l-ascorbic acid levels (r =−0.742, P <0.0001). In stepwise multivariate analysis, low l-ascorbic acid concentration in PAD patients was associated with high CRP level (P =0.0001), smoking (P =0.0009), and shorter absolute claudication distance on a standardized graded treadmill test (P =0.029). ConclusionsVitamin C concentrations are lower in intermittent claudicant patients in association with higher CRP levels and severity of PAD. Future studies attempting to relate vitamin C levels to disease occurrence should include in their analysis an inflammatory marker such as CRP.

Preanalytical quality improvement: in quality we trust

Abstract Total quality in laboratory medicine should be defined as the guarantee that each activity throughout the total testing process is correctly performed, providing valuable medical decision-making and effective patient care. In the past decades, a 10-fold reduction in the analytical error rate has been achieved thanks to improvements in both reliability and standardization of analytical techniques, reagents, and instrumentation. Notable advances in information technology, quality control and quality assurance methods have also assured a valuable contribution for reducing diagnostic errors. Nevertheless, several lines of evidence still suggest that most errors in laboratory diagnostics fall outside the analytical phase, and the pre- and postanalytical steps have been found to be much more vulnerable. This collective paper, which is the logical continuum of the former already published in this journal 2 years ago, provides additional contribution to risk management in the preanalytical phase and is a synopsis of the lectures of the 2nd European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)-Becton Dickinson (BD) European Conference on Preanalytical Phase meeting entitled “Preanalytical quality improvement: in quality we trust” (Zagreb, Croatia, 1–2 March 2013). The leading topics that will be discussed include quality indicators for preanalytical phase, phlebotomy practices for collection of blood gas analysis and pediatric samples, lipemia and blood collection tube interferences, preanalytical requirements of urinalysis, molecular biology hemostasis and platelet testing, as well as indications on best practices for safe blood collection. Auditing of the preanalytical phase by ISO assessors and external quality assessment for preanalytical phase are also discussed.

Diagnosing and monitoring hepatocellular carcinoma with alpha-fetoprotein: new aspects and applications.

Hepatocellular carcinoma is the 5th most common cancer in the world. Prognosis for this disease is poor since hepatocellular carcinoma is mostly diagnosed at an advanced stage. Serum alpha-fetoprotein (AFP) is one of the most common diagnostic markers for hepatocellular carcinoma. However, its diagnostic value is more and more questioned. Therefore, research has focussed on AFP related parameters (AFP mRNA and AFP glycoforms). The aim of this paper is to review the present knowledge on AFP and its related parameters in diagnosing and monitoring HCC. AFP related parameters can be arranged in two types: AFP mRNA and AFP glycoforms. AFP mRNA is a potentially prognostic marker and AFP mRNA assays are based on PCR techniques. The AFP glycoforms have diagnostic potential and assays are based on isoelectric focussing and lectin affinity electrophoretic methods. Up to now the diagnostic use of the AFP related parameters is limited. Although some of them are recommended as a complementary test, they cannot (yet) replace serum AFP as the golden standard of diagnostic markers for hepatocellular carcinoma.

Serum cystatin C concentration compared with other markers of glomerular filtration rate in the old old.

OBJECTIVES: To assess serum cystatin C, compared with other markers of renal function, as a marker of renal function in the old old (aged 85 and older).

Iron status and the outcome of HIV infection: an overview

BACKGROUND Theoretical considerations and experiments in the laboratory suggest that excessive iron stores may have an adverse effect on immunity. If so, high iron stores might be especially a problem in patients with human immunodeficiency virus (HIV) infection. OBJECTIVE AND STUDY DESIGN Review published clinical studies that provide information regarding the effect of iron status on the outcome of HIV infection. RESULTS Four clinical observations have provided some perspective on the effect of iron status on the outcome of HIV-1 infection. First, in a retrospective study of HIV-positive thalassemia major patients, the rate of progression of HIV disease was significantly faster in patients with lower doses of desferrioxamine and higher serum ferritin concentrations. Second, the inadvertent simultaneous administration of low doses of oral iron with dapsone for the prophylaxis of Pneumocystis carinii pneumonia in HIV-positive patients may have been associated with excess mortality. Third, a study of haptoglobin polymorphisms in HIV-positive subjects indicated that the haptoglobin 2-2 polymorphism is associated with higher iron stores and shortened survival as compared with the haptoglobin 1-1 or 2-1 phenotypes. Fourth, a retrospective study of bone marrow macrophage iron in HIV-positive patients suggested that survival is shorter with high iron stores. CONCLUSION These four observations raise the possibility that high iron status may adversely influence the outcome of HIV-1 infection.

The role of automated urine particle flow cytometry in clinical practice

Urine particle flow cytometers (UFC) have improved count precision and accuracy compared to visual microscopy and offer significant labor saving. The absence of an internationally recognized reference measurement procedure, however, is a serious drawback to their validation. Chamber counting by phase contrast microscopy of supravitally-stained uncentrifuged urine is considered the best candidate for reference. The UF-100 (Sysmex Corporation, Japan) identifies RBC, WBC, squamous epithelial cells, transitional epithelial and renal tubular cells (SRC), bacteria, hyaline and inclusional casts, yeast-like cells, crystals and spermatozoa, using argon laser flow cytometry. Evaluations have established acceptable linearity over useful working ranges, with an imprecision that is consistently and significantly less than microscopy, and with negligible carry-over. Comparisons of UFC with chamber counts, quantitative urine microscopy, sediment counts, test strips, bacterial culture and urine density are reviewed. Clinical studies include diagnosis and monitoring of urinary tract infection; localization of the sites of hematuria; and diagnosis, monitoring and exclusion of renal disease. The most popular approach is to combine test strips with UFC for primary screening either always by both methods or by using test strips for analytes unrelated to particles analyzed by UFC. Expert systems now exist combining both test modalities based on user definable decision rules. The implementation of such a strategy significantly reduces microscopy review and saves time and expense without diminishing clinical utility.

Factors influencing ribavirin-induced hemolysis

BACKGROUND/AIMS One of the major side effects of the combination therapy for chronic hepatitis C is ribavirin-induced hemolytic anemia. Little is known about variables influencing this anemia. Our study tried to search for these variables in a large group of patients with hepatitis C treated with the combination therapy. METHODS Two hundred and forty-four patients chronically infected with the hepatitis C virus were treated either with induction treatment (daily dose of interferon) or with a standard treatment (interferon thrice weekly). Both groups received 1,000-1,200 mg of ribavirin from week 4 until the end of the treatment. The drop in hemoglobin level was defined as the difference between the pretreatment hemoglobin level and the hemoglobin level at week 8. Seventeen variables which could possibly influence this drop in hemoglobin level were examined. RESULTS After multivariate analysis, the drop in hemoglobin level was only significant influenced by pretreatment platelet level, treatment and haptoglobin phenotype. The ribavirin dose did not influence the drop in hemoglobin level or the early virological response. CONCLUSIONS Ribavirin-induced hemolysis is influenced by the pretreatment platelet level, the administered amount of alpha-interferon and the haptoglobin phenotype. A careful search for the minimal dose of ribavirin needed in combination treatment is necessary.