Child sexual behavior inventory: A Dutch-speaking normative sample

OBJECTIVES

To describe normative sexual behavior in Dutch-speaking children; to assess the frequencies of different types of sexual behaviors reported in children by their parents; to analyze the relation of these sexual behaviors to demographic, personal, familial, and general behavioral variables; and to compare the Dutch-speaking sample with American samples.

METHOD

Nine hundred seventeen children (2-12 years of age), screened to exclude sexual abuse, were rated by their caregiver via parent report consisting of the translated Dutch version of the Child Sexual Behavior Inventory, the Child Behavior Checklist, a life event checklist, and a questionnaire assessing family nudity and parental attitudes regarding sexuality.

RESULTS

Frequencies of a wide variety of sexual behaviors for 2- to 5-, 6- to 9-, and 10- to 12-year-old children are presented. Sexual behavior was found to be related to the child's age, maternal education, family nudity, and parental attitudes toward sexuality. The positive relation to general behavioral problems was confirmed. Findings were primarily similar to previously published American studies.

CONCLUSION

Our study confirms that sexual behavior in children is varied and related to developmental, personal, and familial factors. The relative frequency of the wide variety of sexual behaviors in a Dutch-speaking normative sample is comparable to American samples.

Definition of a critical T cell threshold for prevention of GVHD after HLA non-identical PBPC transplantation in children

The aim of this study was to reduce the rate of graft failure after HLA non-identical stem cell transplantation by using G-CSF mobilized CD34+ peripheral blood progenitor cells (PBPC), either in combination with bone marrow or as single grafts. To prevent GVHD, PBPC were highly purified, resulting in a 5 to 6 log T cell depletion. In additon to T cell depletion no further GVHD prophylaxis was used. We transplanted 23 pediatric patients with life-threatening malignant or non-malignant hematological disorders, who had no available matched donor. Engraftment was obtained in 18 of 21 evaluable patients. Five patients developed acute GVHD of grade II and III, which became chronic in four cases and was fatal in four. The use of highly purified PBPC allowed the exact quantification of residual T cells in the grafts and a strict correlation between the residual T cell load and the development of GVHD was observed: patients with GVHD had received numbers of T cells between 8 and 20 x 104/kg, whereas patients without GVHD were grafted with T cell numbers ranging from 0.7 to 6.0 x 104/kg. We therefore clearly demonstrate that a residual T cell content of <5 x 104/kg is safe for prevention of GVHD after HLA non-identical PBPC transplantation in children.

Association of reticular dysgenesis (thymic alymphoplasia and congenital aleukocytosis) with bilateral sensorineural deafness

Reticular dysgenesis is a rare congenital disorder characterized by severe combined immunodeficiency and profound neutropenia, curable to date, only by bone marrow transplantation. This report describes the association of bilateral sensorineural deafness with this disease.

Listeria monocytogenes and recurrent mycobacterial infections in a child with complete interferon-gamma-receptor (IFNgammaR1) deficiency: mutational analysis and evaluation of therapeutic options

We describe the history of a girl with interferon-gamma-receptor (IFNgammaR1) deficiency and studies performed to identify the molecular and clinical characteristics of this recently discovered disorder. This is the first report of a child from Northern Europe with IFNgammaR1 deficiency. The patient, now 7 years old, first presented with swelling and reddening at the Bacille Calmette-Guerin (BCG) vaccination site, swelling of lymph nodes, hepatomegaly, and an unusually severe varicella rash at the age of 4 months. At that time, she was diagnosed with BCG histiocytosis without typical granuloma formation and was treated with antituberculous agents. During the clinical course of her illness, several different types of atypical mycobacteria and (for the first time in an IFNgammaR1-deficient patient) Listeria monocytogenes were detected. Flow cytometric analysis showed that the patient's monocytes could not bind a monoclonal antibody specific for the IFNgamma-receptor. Our analysis of mRNA derived from the alpha-chain (IFNgammaR1) gene of this receptor revealed deletions of 173 bp and 4 bp in cDNA sequences originating from individual alleles. The 173 bp deletion was located between nucleotide positions 200 and 372, exactly matching those of exon 3, and the 4 bp deletion was located between nucleotide positions 561 and 564 of the coding region of the cDNA. Analysis of genomic DNA revealed the presence of a G to T transition at the 5'end of the splice consensus sequence of intron 3, which explains the absence of exon 3. The other allele carried the 4-base-pair deletion (ACTC) at nucleotide positions 15-18 of exon 5. Twelve months after an allo\geneic bone marrow transplantation, the patient had clinically improved.

Influence of severe combined immunodeficiency phenotype on the outcome of HLA non-identical, T-cell-depleted bone marrow transplantation: a retrospective European survey from the European group for bone marrow transplantation and the european society for immunodeficiency

We analyzed the outcomes of 214 HLA non-identical T-cell-depleted bone marrow transplantations (BMTs), performed in 178 consecutive patients for treatment of severe combined immunodeficiencies (SCID). Patients were treated in 18 European centers between 1981 and March 1995. SCID variants, that is, absence of T and B lymphocytes (B-) or absence of T cells with presence of B lymphocytes (B+) were found to have a major influence on outcome. The disease-free survival was significantly better for patients with B+ SCID (60%) as compared with patients with B- SCID (35%) (P =.002), with a median follow-up of 57 months and 52 months, respectively. Other factors associated with a poor prognosis were the presence of a lung infection before BMT (odds ratio = 2.47 [1.99-2.94]) and the use of monoclonal antibodies for T-cell depletion of the graft (odds ratio = 1.67 [1. 18-2.15]). Additional factors influencing outcome were age at BMT (<6 months) and period during which BMT was performed. Better results were achieved after 1991. Reduced survival of patients with B- SCID was associated with a higher incidence of early deaths from infection, a diminished rate of marrow engraftment, a trend to a higher incidence of chronic graft-versus-host disease, and slower kinetics of T/B immune function development. In both groups of patients, the use of busulfan (8 mg/kg total dose) and cyclophosphamide (200 mg/kg total dose) as a conditioning regimen provided the best cure rate (74% for patients with B+ SCID and 43% for patients with B- SCID, respectively), although results were not statistically significantly different from other regimens. This retrospective analysis should lead to the design of adapted measures to the performance of HLA non-identical BMT in patients with distinct SCID conditions.

Mutations in the gene for the common gamma chain (gammac) in X-linked severe combined immunodeficiency

X-linked severe combined immunodeficiency (XSCID) constitutes a disorder of the immune system caused by mutations in the gene encoding the common gamma chain (gammac), a subunit of the IL-2, IL-4, IL-7, IL-9 and IL-15 receptors, which are necessary for lymphocyte development and function. In this study the IL2RG gene of 31 patients with severe combined immunodeficiency (SCID) was examined by nonradioactive single-strand conformation polymorphism and sequence analysis. Among the 11 patients with XSCID, ten different mutations were identified in the IL2RG gene, including eight novel mutations. Ninety percent of the mothers of the XSCID patients are carriers of the mutated allele. One patient showed low numbers of B-cells, a striking deviation from the classical B-cell-positive and T-cell-negative phenotype.

Mobilization and collection of allogeneic peripheral blood progenitor cells for transplantation

A median dose of 11 (6-17) microg G-CSF per kg and day was given to 96 (49 female, 47 male) healthy family donors in order to mobilize and to collect peripheral blood progenitor cells (PBPC) for allogeneic transplantation. Donor age was 36 (17-76) years. The leukocytes of the donors increased to 46 (12-115) x 10(9)/l on days 4-6 of G-CSF treatment with a median of 71 (2-657) CD34+ cells per microl, respectively. Female and older donors seem to have a lower response to G-CSF. About 32% of the donors suffered from side-effects of G-CSF requiring analgetics. A total of 197 stem cell aphereses were performed using the COBE Spectra cell separator. Median apheresis time was 225 (118-300) min processing 11.8 (5.7-20) l blood, collecting 5.3 (1.7-14.9) x 10(10) nucleated cells and containing 0.7 (0.1-3.7)% CD34+ cells. Severe citrate toxicity occurred in 5% of the donors. Retransfusion of autologous platelets post apheresis was necessary in 16% of the donors because of a platelet count <80 x 10(9)/l. An insufficient number of stem cells was collected in four female donors due to a very poor response to G-CSF. In conclusion, the collection of allogeneic G-CSF-mobilized PBPC is safe and effective. One or two aphereses were sufficient in 91% of the donors to achieve >4 x 10(6) CD34+ cells per kg. In 4% of the donors an additional bone marrow harvest or the use of an alternative donor was necessary because of a poor mobilization.

Long-term immune reconstitution and outcome after HLA-nonidentical T-cell-depleted bone marrow transplantation for severe combined immunodeficiency: a European retrospective study of 116 patients

We have performed a retrospective analysis of the development of T- and B-cell functions after HLA-nonidentical T-cell-depleted bone marrow transplantation (BMT) performed in 193 patients with severe combined immunodeficiency (SCID) at 18 European centers between December 1982 and December 31, 1993. One hundred sixteen of 193 patients were alive with evidence of engraftment 6 months after BMT. Development of T-cell function occurred earlier than B-cell function and was achieved more frequently up to the time of last follow-up. The median time to achieve normal T-cell function was 8.7 months, whereas the median time to achieve normal B-cell function was 14.9 months. Twenty-four patients died later than 6 months post-BMT, mainly due to chronic graft-versus-host disease (cGVHD) and/or viral infection. Absence of T-cell reconstitution 6 months after BMT, unlike absence of B-cell reconstitution, was associated with a poor outcome. Two additional factors were associated with a poor outcome: presence of cGVHD 6 months after BMT and B- SCID versus B+ SCID. However, two of these three factors remained as significant prognostic factors in a multivariate analysis: the absence of T-cell function and the presence of cGVHD 6 months after BMT. Analysis of the factors influencing the development of immune reconstitution showed that T- and B-cell functions occurred earlier and more frequently in B+ SCID versus B- SCID patients. Acute GVHD was associated with a slower development of T-cell function at 6 months, and cGVHD had a negative influence on the development of T-cell function afterwards, but neither acute nor chronic GVHD was found to influence the development of B-cell function. Once engraftment occurred, whether patients had or had not received Busulfan in the conditioning regimen did not influence the kinetics and quality of T-cell function development. In a multivariate study, two factors were found to influence the T-cell function 6 months after BMT: type of SCID and acute GVHD. The results of this retrospective analysis should lead to new protocols adapted to SCID disease, considering that disease-related as well as BMT-related parameters influence the development of immune function and thereby long-term outcome after HLA-nonidentical T-cell-depleted BMT.

Bone marrow transplantation in congenital immunodeficiency diseases

Bone Marrow transplantation (BMT) is the treatment of choice in a large number of primary immunodeficiencies, for which this treatment is potentially curative. BMT needs to be considered as soon as possible after diagnosis because these disorders usually run an unpredictable course and may be rapidly fatal. Beside conventional HLA-matched donor BMT, there is growing and increasingly favourable experience with alternative, in particular HLA-haploidentical donors. In this review, current results of BMT are presented.

Calculation of residence times and radiation doses using the standard PC software Excel

We developed a program which aims to facilitate the calculation of radiation doses to single organs and the whole body. IMEDOSE uses Excel to include calculations, graphical displays, and interactions with the user in a single general-purpose PC software tool. To start the procedure the input data are copied into a spreadsheet. They must represent percentage uptake values of several organs derived from measurements in animals or humans. To extrapolate these data up to seven half-lives of the radionuclide, fitting to one or two exponentional functions is included and can be checked by the user. By means of the approximate time-activity information the cumulated activity or residence times are calculated. Finally these data are combined with the absorbed fraction doses (S-values) given by MIRD pamphlet No. 11 to yield radiation doses, the effective dose equivalent and the effective dose. These results are presented in a final table. Interactions are realized with push-buttons and drop-down menus. Calculations use the Visual Basic tool of Excel. In order to test our program, biodistribution data of fluorine-18 fluorodeoxyglucose were taken from the literature (Meija et al., J Nucl Med 1991; 32:699-706). For a 70-kg adult the resulting radiation doses of all target organs listed in MIRD 11 were different from the ICRP 53 values by 1%+/-18% on the average. When the residence times were introduced into MIRDOSE3 (Stabin, J Nucl Med 1996; 37:538-546) the mean difference between our results and those of MIRDOSE3 was -3%+/-6%. Both outcomes indicate the validity of the present approach.

German consensus on immunogenetic donor search for transplantation of allogeneic bone marrow and peripheral blood stem cells

In Germany allotransplantation of bone marrow or peripheral blood stem cells is presently performed by 34 different teams operating more or less independently. Thus, strategies of immunogenetic donor search, use of the various tissue typing techniques and policy on acceptable HLA mismatches in related and unrelated settings may vary considerably from one transplant centre to another. This paper summarises the results of the first German consensus meeting on immunogenetic donor search for bone marrow/peripheral blood stem cell grafting. The main goal of the participating transplant physicians and immunogeneticists was to define national standards for the above issues.

Serum bone alkaline phosphatase is superior to plasma levels of bone matrix proteins for assessment of bone metabolism in patients receiving renal transplants

The plasma concentrations of two bone matrix proteins (osteocalcin, osteonectin) were monitored in 56 samples from 14 patients receiving renal transplants and the values compared with serum bone alkaline phosphatase mass concentrations and osteotropic hormone levels (parathyroid hormone, calcitriol). There were no significant changes in the concentrations of plasma osteonectin at any time after transplantation, as compared with the values before transplantation (P > 0.1). None of the plasma samples showed osteonectin levels above the reference interval. There was a weak but significant relationship between platelet counts and plasma osteonectin levels (r = +0.322; P < 0.05). Osteocalcin showed a marked decrease of the values 1 week following transplantation as compared with the values before transplantation without further change of the values 1 and 3 months after transplantation (P > 0.5) whereas 3 months after transplantation bone alkaline phosphatase levels were higher than before transplantation (P < 0.05). Multiple regression analysis (performed with data from 42 samples obtained after transplantation) revealed serum creatinine as an independent predictor of plasma osteocalcin whereas serum calcitriol was an independent predictor of serum bone alkaline phosphatase (P < 0.05). No correlation was observed between serum calcitriol/plasma parathyroid hormone on the one hand and plasma osteocalcin on the other (P > 0.05). After transplantation there was a lack of correlation between serum bone alkaline phosphatase mass concentrations and plasma osteocalcin values (P > 0.05). In conclusion, serum bone alkaline phosphatase should be preferred to bone matrix proteins for the assessment of bone metabolism in patients receiving renal transplants: (a) bone alkaline phosphatase-but not osteocalcin-is significantly correlated with calcitriol and adequately reflects increased bone formation after renal transplantation; (b) interpretation of osteocalcin values is severely hampered by their strong correlation with serum creatinine concentrations; (c) plasma osteonectin determinations are not useful for monitoring bone formation.

Allogeneic bone marrow transplantation for chronic myelomonocytic leukemia in childhood: a report from the European Working Group on Myelodysplastic Syndrome in Childhood

PURPOSE

To evaluate the role of allogeneic bone marrow transplantation (BMT) in children with chronic myelomonocytic leukemia (CMML).

PATIENTS AND METHODS

Forty-three children with CMML given BMT and reported to the European Working Group on Myelodysplastic Syndrome in Childhood (EWOG-MDS) data base were evaluated. In 25 cases, the donor was a human leukocyte antigen (HLA)-identical or a one-antigen-disparate relative, in four cases a mismatched family donor, and in 14 a matched unrelated donor (MUD). Conditioning regimens consisted of total-body irradiation (TBI) and chemotherapy in 22 patients, whereas busulfan (Bu) with other cytotoxic drugs was used in the remaining patients.

RESULTS

Six of 43 patients (14%), five of whom received transplants from alternative donors, failed to engraft. There was a significant difference in the incidences of chronic graft-versus-host disease (GVHD) between children transplanted from compatible/one-antigen-mismatched relatives and from alternative donors (23% and 87%, respectively; P < .005). Probabilities of transplant-related mortality for children given BMT from HLA-identical/one-antigen-disparate relatives or from MUD/ mismatched relatives were 9% and 46%, respectively. The probability of relapse for the entire group was 58%, whereas the 5-year event-free survival (EFS) rate was 31%. The EFS rate for children given BMT from an HLA-identical sibling or one-antigen-disparate relative was 38%. In this latter group, patients who received Bu had a better EFS compared with those given TBI (62% v 11%, P < .01).

CONCLUSION

Children with CMML and an HLA-compatible relative should be transplanted as early as possible. Improvement of donor selection, GVHD prophylaxis, and supportive care are needed to ameliorate results of BMT from alternative donors.

Two novel missense and frameshift mutations in exons 5 and 6 of the purine nucleoside phosphorylase (PNP) gene in a severe combined immunodeficiency (SCID) patient

Four percent of human severe combined immunodeficiency cases are caused by a deficiency of the enzyme purine nucleoside phosphorylase (PNP). In this study we investigated the molecular basis for this rare autosomal recessive disease. Sequence analyses led to the identification of two new mutations in the PNP gene: an A to G transition in exon 5, which leads to the substitution of tyrosine 192 by a cysteine residue, and a 1-bp deletion in exon 6, which causes premature translation termination of the PNP protein. Both PNP mutations affect predicted major structural motifs of the protein and result in post-translation instability of the enzyme.

Improved lectin agglutination method for T-cell depletion of HLA-mismatched bone marrow grafts in children

For T-cell depletion in HLA-nonidentical bone marrow transplantation of children with malignant diseases, we improved the original lectin/rosetting method described in 1981 by adding anti-CD2/3 coated donor red blood cells to the combination to achieve lectin agglutination in one step. Further improvements in handling led to a shortened and simplified method and better quality of the graft. Five bone marrow grafts prepared with this modified protocol contained a median number of 6 (0-28) x 10(4) T-cells per kg, corresponding to 0.02 (0-0.08)% CD3+ cells and 6 (3.7-10.5) x 10(6) CD34+ cells per kg at a median body-weight of 7 (5-38)kg. The overall recoveries after T-cell depletion were: NC 17 (10-44)%, CD34+ cells 61 (22-100)%, and CFU-GM 55 (29-212)%.

Combined CD34 positive plus CD2 negative selection for effective T-cell depletion as GvHD-prophylaxis in HLA-nonidentical blood progenitor cell transplantation

G-CSF mobilized, T-cell-depleted peripheral blood progenitor cells (PBPC) and T-cell-depleted bone marrow (BM) were given to seven children (6 AL, 1 SCID) to prevent severe graft-versus-host-disease (GvHD) as well as graft rejection after transplantation from HLA-nonidentical parental donors. BM was T-cell-depleted by lectin agglutination and E-rosetting. For T-cell-depletion of the PBPC grafts a combination of CD34+ selection with the Ceprate SC immunoadsorption system and a subsequent depletion of CD2+ cells with immunomagnetic Dynabeads was used. The overall recovery was 0.3 (0.1-1.2)% for nucleated cells, 29 (18-45)% for CD3+ cells, respectively. The purity of CD34+ cells was 87 (68-97)% with a 0.3(0.05-0.7)% residual CD3+ T-cell contamination. In spite of the large T-cell number in the PBPC grafts the combination of CD34 positive and subsequent CD2 negative selection achieved a more than 4 log T-cell depletion and prevents severe GvHD even in HLA-nonidentical transplantation. In addition, if a high dose of progenitor cells ensures stable engraftment, this new approach could increase the possibility of wider use of HLA-mismatched family donors for transplantation.

RAG mutations in human B cell-negative SCID

Patients with human severe combined immunodeficiency (SCID) can be divided into those with B lymphocytes (B+ SCID) and those without (B- SCID). Although several genetic causes are known for B+ SCID, the etiology of B- SCID has not been defined. Six of 14 B- SCID patients tested were found to carry a mutation of the recombinase activating gene 1 (RAG-1), RAG-2, or both. This mutation resulted in a functional inability to form antigen receptors through genetic recombination and links a defect in one of the site-specific recombination systems to a human disease.

Comparison of biochemical markers of bone resorption in patients with metabolic and malignant bone diseases

The clinical usefulness of the urinary excretion of three bone resorption markers is compared in patients after renal transplantation and in tumour patients with and without bone metastases. The markers were the 3-hydroxypyridinium derivatives pyridinoline and deoxypyridinoline (pyridinium cross-links; measured by a polyclonal enzyme immunoassay), the cross-linked N-telopeptid-to-helix domain of type I collagen and the destruction products of type I collagen metabolism cross-reacting with a peptide sequence of the alpha 1-chain of the C-terminal telopeptide region of type I collagen (CrossLapsTM). In patients receiving renal transplantation the discriminating power of N-telopeptides was superior to that of pyridinium cross-links and CrossLapsTM, with Z scores (number of SDs from apparently healthy controls) of 6.61, 2.17 and 1.35, respectively. However, the pyridinium cross-links were the only markers for bone resorption which showed a significant increase with time (P < 0.001). Receiver operating-characteristic analysis for discriminating patients with bone metastases from those without revealed that the accuracy was 0.81 for pyridinium cross-links, 0.76 for the N-telopeptides and 0.61 for CrossLapsTM. The discriminating power for patients with bone metastases was higher for pyridinium cross-links and N-telopeptides than for CrossLapsTM, with Z scores (number of SDs from patients without bone metastases) of 4.38, 3.00 and 1.24, respectively. Linear correlation coefficients for the different markers were between +0.35 and +0.65 in patients receiving renal transplants, and between +0.58 and +0.84 in patients with bone metastases. In conclusion, in patients with metabolic and malignant bone diseases there are marked differences in the diagnostic performance of different biochemical markers of bone resorption. It is suggested that this may reflect the different facets of bone resorption or the different metabolic fates of the marker substances examined.

Detection of Candida albicans DNA with a yeast-specific primer system by polymerase chain reaction

The in vitro and in vivo selectivity and sensitivity of a yeast-specific primer system was investigated. A two-step polymerase chain reaction (PCR) was used: the first amplified a 245-bp fragment of the gene for cytochrome P450L1A1 and the second a product of 193 bp. This nested PCR produced an approximately 1000-fold increase in the sensitivity of the test for Candida albicans DNA compared with the first primer pair. The lower level of sensitivity of the test in physiological saline and tissue homogenate was about 10 C. albicans cells ml-1. On the other hand, the sensitivity of the nested PCR method was reduced by a factor of more than 1000 when C. albicans was fixed with 4% formalin. After i.v. injection of different doses of C. albicans into mice, the yeast could be demonstrated in blood and in six different organs. The nested PCR was to some extent more sensitive than culturing for the detection of the yeast in the specimens of organs such as lung, cardiac muscle, liver, kidneys and brain. In contrast, in blood and spleen the culture was superior to the PCR technique used. Nested PCR is thus a useful additional method for the demonstration of yeasts.

Bone marrow transplantation in immunodeficiency diseases

Bone marrow transplantation (BMT) has become the treatment of choice in an increasing number of primary immunodeficiency disorders. In many of these otherwise lethal genetic diseases, BMT can completely reverse the immunological abnormality and patients may be permanently cured. In this review, current approaches in the application of this treatment and results obtained in various entities of primary immunodeficiencies are presented. A significant prognostic factor for the outcome is the clinical condition of the patient at the time of BMT, and prompt recognition of these rare disorders remains an important prognostic factor for BMT.

[Standardized measurement of surface tension of tracheal secretions of newborn infants for diagnosis of surfactant deficiency--secretory immunoglobulin A as a dilution marker]

The surface tension value (gamma min) of tracheal aspirate samples (TA) from newborns depends on lung maturity and is determined by concentrations of surfactant components (phospholipids, surfactant proteins, ions). During tracheal aspirate collecting the aspirate is diluted with physiological saline. Information about TA dilution is necessary for a standardized surface tension measurement. The purpose of this study was to establish an ELISA for determination of secretory IgA (SIgA), to determine the cutoff value of SIgA for surface tension measurement in tracheal aspirates and to test SIgA as marker for tracheal aspirate dilution.

PATIENTS

In group 1 (normal range determination of gamma min) pharyngeal aspirates of 42 healthy newborns (nb) were investigated. In group 2 (determination of SIgA cutoff value) 15 TA and 8 pharyngeal aspirates of 23 pulmonary healthy nb (group 3) were used for validation of SIgA cutoff value. In group 4 36 TA of 22 nb with respiratory distress syndrome were studied.

METHOD

The gamma min of group 1 were measured to establish the range of normal gamma min. The TA of group 2 were diluted stepwise and the dependence of gamma min on SIgA concentration were depicted in a diagram. The SIgA cutoff value was estimated by these dilution curves. Below this value the TA are very diluted and a measurement of gamma min is not useful. To test the reliability of SIgA as dilution marker the gamma min and SIgA values of TA from group 3 were determined. After exclusion of TA with reduced SIgA the gamma min of group 3 and 4 were compared.

RESULTS

For the enzyme immunoassay following performance characteristics were determined: the accuracy (recovery): 95.6%, sensitivity: 4 ng/ml, and precision (intra- and interassay coefficient of variation): 9.8 and 19.1%, respectively. The range of normal gamma min (median (5th and 95th percentile)) amounts to 23.0 (14.8 and 28.7) mN/m. A SIgA cutoff value of 80 ng/ml was estimated. The gamma min from 8 of 27 TA (group 3) were above the normal range of gamma min during examination of the estimated SIgA cutoff value. 5 of these 8 TA had concentrations of SIgA below the cutoff point and could be excluded with the help of SIgA as dilution marker. The median of gamma min was significantly lower (p < 0.001) in group 3 (18.3 mN/m) in comparison to the median (35.8 mN/m) of group 4 (nb with respiratory distress syndrome).

CONCLUSION

The performance characteristics of the SIgA enzyme immunoassay and the tested reliability of the SIgA cutoff value demonstrate, that a simple determination of surfactant deficiency by surface tension measurement of TA is possible using the concentration of SIgA as dilution marker.

Surface tension measurements on pharyngeal and tracheal aspirate samples from newborns without and with respiratory distress syndrome

A rapid test determining surfactant deficiency or dysfunction might help in controlling therapy of respiratory distress syndrome (RDS). Forty tracheal aspirate samples (TA) from 40 newborns with RDS (group 1) and 46 pharyngeal from 46 newborns without RDS (reference group) were analyzed by surface tension measurement with the pulsating bubble surfactometer. Five surface tension parameters were compared. Marked differences between both groups could be noted for the parameters: minimum surface tension (gamma min) and stability index (S), while maximum surface tension (gamma max), surface tension after a 10-second adsorption period and hysteresis area did not have striking differences. The parameters gamma min and S have the highest diagnostic value for determining surfactant deficiency or dysfunction. For a rapid test it is sufficient to compare gamma min with reference values, because S is calculated from gamma min and gamma max.