Assessment of vitamin D status and serum CrossLaps levels in adults with primary lactose malabsorption.

BACKGROUND/OBJECTIVES: Primary adult-type lactose malabsorption (PALM) is a widespread inherited autosomal recessive condition, which is considered to be associated with osteoporosis. This prospective study aimed at assessing the 25-hydroxy-vitamin D (25(OH)D) status and serum CrossLaps levels in individuals with PALM and normal controls. SUBJECTS/METHODS: All participants (n=210) underwent genotyping for the LCT C/T-13910 polymorphism, 25(OH)D and CrossLaps measurements and clinical examinations. In addition, the anthropometric data (that is, height, weight and body mass index) were determined. RESULTS: Fifty-five individuals with PALM (that is, LCT C/C-13910 homozygotes) showed lower 25(OH)D (mean: 24.95±10.04 vs 28.59±9.56 ng/ml, P=0.018) and higher CrossLaps serum levels (mean: 0.46±0.31 vs 0.43±0.49 ng/ml, P=0.251) compared with 155 normal controls (that is, LCT C/T-13910 hetero- or T/T-13910 homozygotes). Anthropometric data were similar between PALM probands and controls. CONCLUSIONS: Individuals with PALM were found to have lower 25(OH)D and higher CrossLaps serum levels compared with normal controls. In order to preserve life-long bone health, routine 25(OH)D and CrossLaps serum measurements should be performed in individuals with PALM.

Transmission of cytomegalovirus via breast milk to the prematurely born infant: a systematic review.

To analyse current data on transmission of human cytomegalovirus (HCMV) via breast milk with subsequent symptomatic HCMV infection of the preterm infant and to report on long-term follow-up, a systematic literature review was performed using EMBASE, MEDLINE and CINAHL (January 1966 to December 2008) Studies were included for analysis if congenital HCMV infection was excluded and transmission via breast milk was either confirmed or strongly suspected. Twenty-six studies were included for analysis. Maternal HCMV-IgG-positivity was reported to be in the range 51.6-100% (median 81.6%), HCMV-IgG detection in breast milk in the range 67-97.2% (median 80%) and HCMV-positivity of the infants in the range 5.7-58.6%. Symptomatic HCMV disease occurred in 0-34.5% (median 3.7%) and severe sepsis-like syndrome in 0-13.8% (median 0.7%). Data on long-term outcome of preterm infants with symptomatic HCMV infection revealed a low risk for mild neurological and cognitive sequelae, without hearing impairment. Recommendations for high-risk preterm infants diverged markedly. The current data report low rates of symptomatic disease after transmission of HCMV via breast milk to the preterm infant without evidence of certain long-term sequelae. The results of our review do not support a general approach, either by avoidance or pasteurization of breast milk, in high-risk preterm infants.

Competitive and seasonal oxidative stress in elite alpine ski racers.

We investigated competitive- and long-term oxidative stress during a competition season in eight top-ranked members of the Austrian Men's Alpine Ski Team. Serum total peroxides, antibody titers against oxidized LDL (oLAb) and lag time of the degradation of the fluorophore 1-palmitoyl-2-((2-(4-(6-phenyl-trans-1,3,5-hexatrienyl)phenyl)ethyl)-carbonyl)-sn-glycero-3-phosphocholine were measured, along with plasma concentrations of ascorbate, alpha- and gamma-tocopherol, beta-carotene, uric acid and the lipid status. Competitive stress was indicated through an increased post-race uric acid level (286 +/- 50 microM pre-race vs 456 +/- 77 microM post-race, P<0.001) in December. Long-term effects were already apparent in November, with the highest concentrations of total peroxides (680 +/- 458 microM H(2)O(2) equivalents vs December 47 +/- 58 microM H(2)O(2) equivalents and January 15 +/- 28 microM H(2)O(2) equivalents, P<0.001) and a concomitant decrease in oLAb titers with an antibody trough in December (439 +/- 150 mU/mL vs baseline 1036 +/- 328 mU/mL; P=0.003). In January, after recovery, they attained nearly pre-season levels of oxidative stress biomarkers. This study indicates midseason oxidative stress in top-level skiers, which was associated with the performance in these athletes.

Effect on hearing of ganciclovir therapy for asymptomatic congenital cytomegalovirus infection: four to 10 year follow up.

BACKGROUND: Congenital cytomegalovirus infection is the leading identified nongenetic cause of congenital sensorineural hearing loss. Most of the infections are asymptomatic but may be detected from umbilical cord vein and/or newborn serum positivity for human cytomegalovirus immunoglobulin M, and from urine positivity (on polymerase chain reaction) for human cytomegalovirus deoxyribonucleic acid in the newborn period. Children infected by cytomegalovirus may later develop sensorineural hearing loss. In symptomatically infected infants, ganciclovir therapy administered in the neonatal period prevents hearing deterioration. However, preventative therapy of asymptomatic congenital cytomegalovirus disease with ganciclovir is controversial, as side effects such as severe neutropenia may occur during treatment. METHODS: The study population consisted of 23 asymptomatic children with congenital cytomegalovirus infection. Twelve children were treated just after diagnosis of cytomegalovirus infection in the newborn period, with ganciclovir 10 mg/kg bodyweight for 21 days. The other 11 children were observed without therapy. Over a four to 10 year follow-up period, we evaluated all the children's hearing status using pure tone audiometry. RESULTS: All 23 children had normal sensorineural hearing at one year follow up. Five of the 23 children (21.7 per cent) were lost to follow up over the four to 11 year follow-up period. Of the remaining 18 children, sensorineural hearing loss occurred in two (11.1 per cent). Neither child had been treated with ganciclovir in the newborn period. An eight-year-old boy showed bilateral high frequency loss and a 10-year-old girl showed severe unilateral sensorineural hearing loss. In the ganciclovir-treated group (nine children), none showed sensorineural hearing loss. During ganciclovir therapy, moderate neutropenia occurred as a side effect in two out of 12 (16.6 per cent) treated children. Speech and general development were normal in all children. CONCLUSION: Asymptomatic congenital cytomegalovirus infection is likely to be a leading cause of sensorineural hearing loss in young children. Intravenous ganciclovir therapy seems to offer a medical option to prevent subsequent sensorineural hearing loss. Further studies including a greater number of children are needed. Cytomegalovirus screening models are mandatory if medical therapy is to be implemented in time.

Midazolam and its metabolites in brain death diagnosis.

OBJECTIVE: There is only limited knowledge on the pharmacokinetics of midazolam and its active metabolites in potential organ donors. Before establishing the diagnosis of brain death, drugs interfering with the neurological assessment have to be washed out. National guidelines advise a waiting time of 12 hours. The aim of our study was to evaluate whether it is sufficient to rely on a calculated waiting time. METHODS: As examples of typical pharmacokinetics of midazolam and its metabolites, we followed the concentration over time in four potential organ donors with immunoassays and high-performance liquid chromatography (HPLC). RESULTS AND CONCLUSIONS: In each of the 4 patients studied, the elimination of midazolam and/or midazolam metabolites was delayed. As long as brain death diagnosis requires that drugs interfering with the clinical assessment must be at levels below the therapeutic range, monitoring of midazolam and metabolites appears mandatory.

High-performance liquid chromatographic method for the simultaneous determination of cyclosporine A and its four major metabolites in whole blood.

This study aimed to develop a simple and efficient optimized high-performance liquid chromatograph (HPLC) method for simultaneous determination of cyclosporine A (CyA) and its major, partly active metabolites AM1, AM9, AM4N, and AM19 in whole blood from transplant patients using cyclosporine D (CyD) as internal standard. The method used a CN analytical column maintained at 60 degrees C with hexan-isopropanol (93:7, v/v) as mobile phase; detection was at 212nm. Linearity for all five compounds was tested in the range of 31-1500ngml(-1) for CyA and of 31-1000ngml(-1) for metabolites. The limit of detection was found to be 15ngml(-1) for all compounds. This modified, inexpensive method is also suitable for measuring cyclosporine A and metabolite concentrations in routine monitoring of patients undergoing treatment with CyA.

Different effects of abciximab and cytochalasin D on clot strength in thrombelastography.

Maximum amplitude (MA) in thrombelastography (TEG) consists of a plasmatic and a platelet component. To assess the magnitude of the plasmatic component, pharmacological approaches have been proposed to eliminate the platelet component. We evaluated the individual and combined effects of abciximab and cytochalasin D on the MA of TEG. Whole blood, platelet-rich plasma (PRP) and homologous platelet-poor plasma (PPP) from 20 healthy volunteers were spiked with abciximab or cytochalasin D or a combination of both and TEGs performed. Abciximab and cytochalasin D decreased MA in all samples. MA of whole blood (18.6 +/- 3.1 mm) and PRP (33.7 +/- 3.5 mm) spiked with abciximab or cytochalasin D alone (15.0 +/- 2.9 mm and 25.0 +/- 4.0 mm) were significantly higher when compared with abciximab and cytochalasin D combined (10.4 +/- 3.0 and 20.2 +/- 3.5 mm). While MA of PRP and homologous PPP were significantly (P < 0.001) different after individual administration of abciximab and cytochalasin D, combination of both abolished this difference (20.2 +/- 3.5 mm and 20.4 +/- 3.7 mm, P = 0.372). In whole blood of critically ill patients or patients undergoing major surgery there was also a significant difference of MA between abciximab alone and in combination with cytochalasin D (16.5 +/- 11.3 mm and 11.3 +/- 7.7 mm, P < 0.001). This indicates that in contrast to individual administration of abciximab or cytochalasin D, a combination of both compounds eliminates the platelet-specific effect on MA of TEG tracings.

Evaluation of five commercial enzyme immunoassays for the detection of human cytomegalovirus-specific IgM antibodies in the absence of a commercially available gold standard.

In the recent years the number of commercially available immunoassays for the detection of human cytomegalovirus (HCMV)-specific immunoglobulin M (IgM) antibodies has rapidly increased. The aim of the present study was to evaluate five commercial immunoassays for the serological diagnosis of HCMV-infection. These methods, namely the IMx CMV IgM assay, the AxSYM CMV IgM assay (both Abbott), the Gull CMV IgM, the CMV-IgM-ELA test PCS Medac and the Biotest Anti-HCMV recombinant IgM ELISA, were compared for their diagnostic effectiveness and interference with substances eventually producing cross-reactions with HCMV-IgM (Epstein-Barr-virus (EBV)-IgM, rheumatoid factor (RF)). In addition, repeated measurements on samples from kidney and heart transplant recipients with active HCMV infection were examined to compare the temporal development of the HCMV-IgM measured with the five assay systems. Since there is no commercially available gold standard, it was assumed that the true classification, of whether the patient sample is HCMV-IgM positive or negative, was unknown. Hence sensitivity and specificity were assessed based on a maximum likelihood approach using a "latent class" model. The cross-reactions were quantified by a Bayesian statistical model using prior information for the expected prevalences in the EBV-IgM and rheumatoid factor sample groups. The results of the study demonstrated that there are great differences in sensitivity and specificity as well as in cross-reactions with EBV-IgM and RF between the tested ELISAs.

Cytomegalovirus diagnosis in renal and bone marrow transplant recipients: the impact of molecular assays.

BACKGROUND: Cytomegalovirus (CMV) infections are a major threat in transplant recipients. In recent years, new assays for routine CMV diagnosis, based on molecular techniques, have become available. OBJECTIVE: The impact of molecular assays for CMV diagnosis in transplant recipient was evaluated. STUDY DESIGN: A total of 51 transplant recipients were screened for CMV infection. Serological (AxSYM CMV IgG and recombinant CMV IgM assays), antigenemia, CMV DNA (qualitative in house PCR and the quantitative COBAS AMPLICOR CMV MONITOR Test), and CMV mRNA (NucliSens CMV pp67 Test) tests were compared. RESULTS: In 11/20 bone marrow transplant (BMT) recipients and 10/31 renal transplant (RTX) recipients there was no evidence of active CMV infection. Ten RTX recipients and one BMT recipient were antigenemia positive, 21 RTX and seven BMT recipients were PCR positive (qualitative CMV PCR). There were more BMT recipients CMV DNA positive in serum (7/21) than antigenemia positive (1/21). CMV mRNA was found positive in two BMT recipients (one case with no other evidence of CMV infection, the other one CMV DNA positive and antigenemia negative). The only antigenemia positive BMT recipient was found negative for CMV mRNA, but positive in all other tests. Eight RTX recipients were found positive for CMV mRNA. Six of them were also antigenemia positive and five of those were also found positive for CMV IgM. One CMV mRNA positive RTX recipient was CMV IgM positive but antigenemia negative and the other one CMV mRNA positive RTX recipient was found negative in all other tests. Two antigenemia positive RTX recipients were found negative for mRNA and CMV IgM. CONCLUSION: Antigenemia was found to be a good screening test for CMV infection in RTX recipients. In BMT recipients, tests based on molecular techniques appeared to be superior compared to antigenemia.

Evaluation of HbA1c determination methods in patients with hemoglobinopathies.

OBJECTIVE: To evaluate commercially available determination methods for HbA1c in patients with hemoglobin variants. RESEARCH DESIGN AND METHODS: HbA1c values were determined with various commercially available methods, including ion-exchange high-performance liquid chromatography (HPLC), boronate affinity assay, and immunoagglutination in patients with the hemoglobin mutations Hb Graz, Hb Sherwood Forest, Hb O Padova, Hb D, and Hb S. RESULTS: The effect of hemoglobinopathies on glycohemoglobin measurements was highly method dependent. The HPLC methods for HbA1c determination lacked the resolution necessary to differentiate hemoglobin variants. They demonstrated additional peaks in the chromatograms and HbA1c results either too low or too high compared with the nondiabetic reference range. With all immunoassays, Hb Graz demonstrated falsely low values. The other hemoglobinopathies in our study caused falsely low and/or high HbA1c results in immunoagglutination methods. The boronate affinity method showed values in an acceptable range for all hemoglobin variants. CONCLUSIONS: Because of the local occurrence of Hb variants and the ethnic origin of a given population, every individual laboratory must establish and validate its own assay method. In managing diabetic patients, knowledge of hemoglobinopathies influencing HbA1c determination methods is essential because hemoglobin variants could cause mismanagement of diabetes resulting from false HbA1c determinations.

Screening and diagnosis of congenital cytomegalovirus infection: a 5-y study.

Although cytomegalovirus infection is the most common infection transmitted via the placenta, there are no guidelines for routine screening to detect children congenitally infected with cytomegalovirus. From 1993 to 1997, maternal serum and cord vein blood of newborns was screened for HCMV-IgM (n = 21,183). Urine was examined for HCMV-excretion during the first postnatal week to prove HCMV infection in children who expressed HCMV-IgM in cord vein blood (n = 13) or who were born to mothers positive for HCMV-IgM in the serum (n = 234), or when both cord vein blood and maternal serum were positive for HCMV-IgM (n = 6). Congenital HCMV infection was detected in 17 newborns. To determine the incidence of congenital HCMV infection, only those mother/child pairs were selected in whom serum and cord vein blood were investigated (n = 5967 mother/child pairs). In this group 13 newborns were infected. The observed incidence for congenital HCMV infection is 0.21%. It is concluded that that this screening programme will detect those children at risk for congenital HCMV infection. These children have to be examined for virus excretion in the urine. Although the observed incidence is only 0.21%, congenital HCMV infection is a problem that can no longer be neglected because of its long-term sequelae.

Human trophoblast cells are permissive to the complete replicative cycle of human cytomegalovirus.

Human trophoblast cells were permissively infected by human cytomegalovirus. The kinetics of viral immediate-early, early, and late gene expression was clearly delayed compared to that in fibroblasts. Productive infection was unequivocally proven by the detection of virion particles, infectious virus in trophoblast culture supernatant, and cell-to-cell spread of cytomegalovirus from infected trophoblasts to uninfected fibroblasts. These observations indicate that infected trophoblasts may be involved in maternofetal transmission of human cytomegalovirus.

Comparative evaluation of three assay systems for automated determination of hemoglobin A1c.

We evaluated three newly introduced systems for automated determinations of hemoglobin (Hb) A1c, which allow the processing of large amounts of samples in a routine clinical laboratory. We compared these methods--the Variant HPLC, the Hi-Auto A1c analyzer system, and the Roche immunoassay--with the Diamat HPLC system. All showed good precision and good concordance with the Diamat HPLC. The reference range for Hb A1c has to be determined by the laboratory for each assay system. Interference study showed no statistically significant influence of anemia, polycythemia, rheumatoid factor, or chronic hemodialysis, although individual Hb A1c values can be influenced by polycythemia (when measured with the Hi-Auto A1c analyzer) and by chronic hemodialysis (when measured with the Variant HPLC). HPLC was not suitable for measuring Hb A1c in the examined cases of hemoglobin variants; assaying fructosamine seems to be better for monitoring these patients.

[Photometric determination of HbA1c levels in clinical practice]. / Photometrische Bestimmung des HbA1c-Wertes in der Praxis.

This study was undertaken to evaluate the routine use of a new immunological photometer to measure the concentration of HbA1c in whole blood from 155 patients. The basis of the measurement is a latex agglutination reaction in which a monoclonal antibody as epitope recognizes glucose bound to HbA1c. The result is available within 9 min. High-pressure liquid chromatography (HPLC) served as control method. The photometer proved to be very precise (all coefficients of variant < 2.5%), and the values obtained agreed well with those by HPLC (y = 0.952x-0.12; r = 0.986; P < 0.001). The reference ranges for the photometrically measured HbA1c values (4.4-5.9%), obtained for 40 patients, agreed well with those by HPLC (4.6-6.2%). Interference study discovered no effect on the measured value by anaemia, polycythaemia or high rheuma factor (n = 31). In 12 patients on dialysis the photometer recorded significantly lower values than HPLC (P < 0.0005). It is possible that in these cases the photometer values are more accurate because the method is not affected by carbamylated haemoglobin. False results were obtained by the photometer in two patients with leucocytosis (79,000 and 216,000/microliters, respectively) due to chronic lymphocytic leukaemia.

Monitoring of cytomegalovirus disease after heart transplantation: persistence of anti-cytomegalovirus IgM antibodies.

During the first year after orthotopic heart transplantation 39 recipients (given prophylactic immunosuppression with antithymocyte globulin for 7 days after orthotopic heart transplantation and triple drug maintenance therapy) were screened for cytomegalovirus antigenemia and anti-cytomegalovirus immunoglobulin M (index) and immunoglobulin G levels (antibody units) by MEIA-method. Until day 14, all recipients received cytomegalovirus hyperimmunoglobulin at a dosage of 2 ml/kg/day. Four patient groups were defined: group 1 (n = 15) seropositive recipient/seropositive donor, group 2 (n = 9) seronegative recipient/seropositive donor, group 3 (n = 8) seropositive recipient/seronegative donor and group 4 (n = 7) seronegative recipient/seronegative donor. Twenty-four donors and 23 recipients were seropositive for anti-cytomegalovirus immunoglobulin G. After transplantation, 31 recipients tested positive for cytomegalovirus antigenemia before immunoglobulin M elevation and at least 7 days before the onset of clinical symptoms of cytomegalovirus. In group 2, episodes of cytomegalovirus antigenemia appeared earlier, were more frequent, and lasted longer than in groups 1 and 3. Without previous evidence of positive cytomegalovirus antigenemia testing, no sign of cytomegalovirus disease was seen. When cytomegalovirus antigenemia was positive, cytomegalovirus hyperimmunoglobulin was readministered at the same dosage and gancyclovir (1000 mg/day) was given until cytomegalovirus antigenemia disappeared. However, episodes of recurrent cytomegalovirus were observed (2.6 +/- 1.9, 4.3 +/- 1.0, and 2.3 +/- 1.2 in groups 1, 2 and 3, respectively). In groups 1 and 3, the anti-cytomegalovirus immunoglobulin G antibody level remained high during the observation period. In groups 2 and 4 anti-cytomegalovirus immunoglobulin G antibodies were positive because of hyperimmunoglobulin prophylaxis but immunoglobulin G decreased again after discontinuation of the prophylaxis.(ABSTRACT TRUNCATED AT 250 WORDS)

Automated determination of glycated hemoglobin: comparative evaluation of five assay systems.

We evaluated four newly introduced assays for determination of glycated hemoglobin allowing the processing of large amounts of samples in a clinical routine laboratory. These methods were compared to the Bio-Rad Diamat system. The investigated methods were the Merck Hitachi L-9100, a fully automated HPLC analyser, the Abbott IMx glycated hemoglobin ion capture assay, the DAKO HbA1c enzyme linked immunosorbent assay (ELISA), and the Boehringer-Mannheim HbA1c Tinaquant turbidimetric assay. All methods showed generally acceptable precision and good accordance with the Diamat system. Interference study showed influence of anaemia, polycythemia, rheumatoid factor, and chronic hemodialysis on the values of the DAKO ELISA and of anaemia and polycythemia on the values of the Boehringer-Mannheim Tinaquant assay. All of the investigated methods allow referring of results either as measured or standardized HbA1c values, the latter obtained after calibration with reference to an ion exchange high-pressure liquid chromatography method. Our data confirm the feasibility of this kind of standardisation of glycated hemoglobin assays, allowing direct comparison of results from various determination methods.