Actinomyces catuli sp. nov., from dogs

An Actinomyces-like bacterium was recovered from two dogs. Based on cellular morphology and biochemical criteria, the unknown bacterium resembled the genus Actinomyces but it did not appear to correspond to any of the currently recognized species of this genus. PAGE analysis of whole-cell proteins confirmed that the strain was phenotypically distinct from all other Actinomyces species and comparative 16S rRNA gene sequencing showed that the bacterium represents an unknown sub-line within the genus. Based on phenotypic and phylogenetic evidence, it is proposed that the bacterium from dogs be classified as a new species of the genus Actinomyces, Actinomyces catuli. The type strain of Actinomyces catuli is CCUG 41709T (= CIP 106507T).

Actinomyces marimammalium sp. nov., from marine mammals

Three strains of a previously undescribed Actinomyces-like bacterium were isolated from samples taken from two dead seals and a porpoise. Biochemical testing and PAGE analysis of whole-cell proteins indicated the strains were phenotypically similar to each other but different from previously described Actinomyces and Arcanobacterium species. Comparative 16S rRNA gene sequencing studies showed the organisms from marine animals were genetically closely related and represent a hitherto unknown subline within the genus Actinomyces (sequence divergence values > 6% with recognized species). Based on phylogenetic and phenotypic evidence it is proposed that the unknown bacterium from the seals and a porpoise should be classified as Actinomyces marimammalium sp. nov. The type strain is CCUG 41710T.

Determination of xanthine oxidoreductase forms: influence of reaction conditions

Xanthine oxidoreductase (XOR) has been implicated in ischaemia-reperfusion injury, and increases in this enzyme have been found in plasma of patients with different illnesses. The catalytic concentrations of the XOR forms found in plasma, using various reaction conditions, greatly differ in the related literature. We studied the effect of the assay conditions on the xanthine oxidation rate catalysed by the XOR forms. Our results demonstrate inhibition of XOR by the reaction products and a time-dependent decrease in the reaction rates of XOR forms. Substrate consumption and inhibition by the products did not account for this decrease. Determination at 60 min incubation leads to catalytic concentrations up to 80% lower for the XOR forms than those obtained at 10 min. We conclude that elimination of the reaction products (NADH, H(2)O(2) and O(2)) from the reaction mixture, and short incubation times, are necessary for accurate measurement of the XOR activities.

Utility of the antibody response to a conjugated Haemophilus influenzae type B vaccine for diagnosis of primary humoral immunodeficiency

Antibody response to an Haemophilus influenzae type b (Hib)-conjugated vaccine was studied in 59 healthy adults (mean age: 32 yr) and 22 patients with humoral immunodeficiencies (mean age: 32 yr) to determine its usefulness in the diagnosis of defective antibody formation. Twenty of the healthy adults and nine of the patients were also immunized with a pneumococcal vaccine. Serum specific antibodies were measured by ELISA. Adequate response to both vaccines was defined using the lower limit of the two-tailed 90% probability interval of postimmunization specific IgG of the healthy adults. By using this cutoff, responders were considered to be those with an absolute increase in anti-Hib IgG titers higher than 2.28 microgram/ml, and in anti-Streptococcus pneumoniae IgG higher than 395 arbitrary units/ml. With these criteria, 85% (50 of 59) of the healthy adults responded with anti-Hib IgG and 75% (15 of 20) with anti-pneumococcal IgG. All healthy adults receiving both vaccines responded to at least one. None of the patients with humoral immunodeficiencies responded to either vaccine. Evaluation of the antibody response to both the Hib and pneumococcal vaccines may facilitate the diagnosis of humoral immunodeficiency and selection of patients to receive immunoglobulin therapy.

Actinomyces canis sp. nov., isolated from dogs

Three strains of a previously undescribed catalase-positive Actinomyces-like bacterium were isolated from dogs. Biochemical testing and PAGE analysis of whole-cell proteins indicated that the strains were phenotypically highly related to each other but different from previously described Actinomyces and Arcanobacterium species. Sequencing of 16S rRNA showed that the unknown bacterium represents a new subline within a cluster of species which includes Actinomyces hyovaginalis, Actinomyces georgiae, Actinomyces meyeri, Actinomyces odontolyticus, Actinomyces radingae and Actinomyces turicensis. On the basis of phenotypic evidence and 16S rRNA sequence divergence levels (greater than 5% with recognized Actinomyces species) it is proposed that the unknown strains from canine sources be classified as a new species with the name Actinomyces canis sp. nov. The type strain of Actinomyces canis is CCUG 41706T (= CIP 106351T).

Simple method for alpha1-antitrypsin deficiency screening by use of dried blood spot specimens

The use of dried blood spot (DBS) specimens in quantitative alpha1-antitrypsin (alpha1-AT) detection or genetic analysis is limited because protein levels in the samples are low and they contain components that can interfere with polymerase chain reaction amplification. A methodological adaptation was developed to overcome these drawbacks which is discussed here. The study population consisted of 200 healthy volunteers and 300 patients with chronic obstructive pulmonary disease (COPD). DBS specimens were tested for alpha1-AT concentration using a modified nephelometric assay and phenotyped with an isoelectric focusing method. Genetic diagnosis was established by deoxyribonucleic acid sequencing using a simple purification procedure to remove contaminants. The nephelometric method showed a detection limit of 0.284 mg x dL(-1), corresponding to a serum concentration of 13 mg x dL(-1). The correlation coefficient between alpha1-AT concentrations in DBS versus serum samples was R2=0.8674 (p<0.0001). All 200 healthy individuals had DBS alpha1-AT concentrations >1.9 mg x dL(-1), corresponding to 114 mg x dL(-1) in serum samples. One hundred and twenty-five COPD patients (42%) showed alpha1-AT values <1.8 mg x dL(-1). Twenty patients with the PIZ phenotype had alpha1-AT values lower than 0.64 mg x dL(-1). On the basis of genotyping, one COPD patient was classified as heterozygous (PIMM(heerlen)). Selective elution of contaminants resulted in optimal alpha(1)1-antitrypsin genotyping. Because of its sensitivity and excellent correlation with the standard method, the dried blood spot quantitative assay is a reliable tool for routine measurement of alpha1-antitrypsin.

Reclassification of Actinomyces humiferus (Gledhill and Casida) as Cellulomonas humilata nom. corrig., comb. nov

The placement of Actinomyces humiferus within the genus Actinomyces has always been controversial. A humiferus differs from typical members of the genus both phenotypically and in possessing a relatively high DNA G + C content. Comparative 16S rRNA gene sequencing has shown that A. humiferus is related only distantly to other species of the genus Actinomyces and is, in fact, a member of the genus Cellulomonas. On the basis of phylogenetic evidence, it is proposed that A. humiferus be reclassified in the genus Cellulomonas as Cellulomonas humilata nom. corrig., comb. nov.

Detection of specific antibodies to pigeon serum and bloom antigens by enzyme linked immunosorbent assay in pigeon breeder's disease

BACKGROUND

Pigeon breeder's disease is an extrinsic allergic alveolitis in the lungs of sensitised people, caused by hypersensitivity reactions to inhaled pigeon antigens. Antigens from different sources of the animal are used for diagnostic purposes, with serum being the most widely used. Bloom is rarely used; very little is known of its antigenicity and diagnostic performance, particularly when used with the enzyme linked immunosorbent assay (ELISA) method, which is the most popular test as it permits measurement of the antibody response.

METHODS

To (a) standardise an ELISA for the measurement of specific IgG against pigeon serum and pigeon bloom extract; (b) to establish reference values for specific IgG in 73 non-exposed controls, (c) to show the presence of specific IgG against pigeon serum and bloom in serum samples of 17 patients with bird fancier's lung and 11 asymptomatic fanciers, and (d) to study the similarity of the two antigen sources by cross reactivity experiments.

RESULTS

Reference values of specific IgG were defined with the 97.5 percentile (367.9 U/ml for pigeon serum and 953.7 U/ml for pigeon bloom extract). Of symptomatic patients 100% had values higher than the cut off for both antigens. In asymptomatic fanciers values were higher than the cut off for pigeon serum in 45% and bloom extract in 54%. Cross reactivity experiments showed that the two antigens differed in antigenic content although some components may be common to both.

CONCLUSION

The ELISA methods used proved to be useful tools for evaluating specific IgG antibody responses against both antigens. The diagnostic performance of both ELISA methods performed with these antigen sources was similar, showing very high sensitivity but moderate specificity. Although some antigenic similarity was found between pigeon serum and bloom extract, cross reactivity studies showed that various antigens seemed to be specific to the bloom extract. However, the antigens responsible for pigeon breeder's disease seem to be present in both antigenic sources.

Identification and molecular characterization of the new alpha-1-antitrypsin deficient allele PI Y barcelona (Asp256-->Val and Pro391-->His). Mutations in brief no. 174. Online

To characterize the molecular basis of the "new" alpha1-antitrypsin (alpha1AT) deficient variant, PI Y barcelona, DNA sequence analysis of the coding exons of the alpha1AT gene was carried out using an amplification DNA technique and direct sequencing. The PI Y barcelona allele differs from the normal M1(Val213) allele sequence by two point substitutions: a transversion of GAT TO GTT in exon III in the codon for residue 256, resulting in the amino acid change of Asp256 to Val256, and a transversion of CCC to CAC in exon V in the codon for residue 391, resulting in the amino acid substitution of Pro391 to His391. On isoelectric focusing analysis these substitutions result in a cathodal migration of the "new" variant close to the PI Z. The index case, diagnosed with severe obstructive pulmonary disease, initially phenotyped a PI ZZ, was homozygous for PI Y barcelona. The patient's serum alpha1AT level was 16 mg/dL (normal values 115-220 mg/dL). Inheritance of the PI Y barcelona was confirmed by family study. Amino acid substitution in postion 391 occurs in the C-terminal peptide region, which shows a high degree of homology with the family of serpins. Pro391 is considered to have special relevance in the secretion of alpha1AT.

Determination of lamotrigine in human serum by liquid chromatography

A rapid high-performance liquid chromatographic method was developed using a short silica column (30 mm x 4.6 mm) with an aqueous methanol mobile phase consisting of methanol-water-NH4H2PO4 (94:5.96:0.04) adjusted to a final apparent pH of 5.0 and pumped at a flow-rate of 1 ml/min. Ultraviolet detection was carried out at a wavelength of 280 nm, and serum samples were prepared for HPLC analysis by extraction into dichloromethane after basification. Lamotrigine was eluted at 0.96 min. Within-day variation of the method was 4.46% at 0.75 microg/ml and 2.37% at 6.0 microg/ml, and day-to-day variation was 9.10% at 0.75 microg/ml and 7.28% at 6.0 microg/ml.

Rapid detection of lamivudine-resistant hepatitis B virus polymerase gene variants

The amino acid substitution from methionine to valine or isoleucine at the YMDD (tyrosine, methionine, aspartate, aspartate) motif of the HBV polymerase gene is the main mutation responsible for resistance to lamivudine treatment. Detection of emerging HBV variants by direct sequencing of the HBV genome is excessively time-consuming for studying large numbers of clinical samples. The aim of the study was to analyse the emergence of lamivudine-resistant HBV genotypes by means of restriction fragment length polymorphism (RFLP) of the PCR product generated from a fragment of domain C of the polymerase gene, in clinical samples from patients receiving treatment. The results with this method were compared with those obtained with a direct sequencing technique. In total, 139 serum samples were studied from 37 patients with chronic hepatitis B, obtained at pre-treatment and at 9, 12, 18 and 24 months of treatment. Variants were detected by cleavage of the products of the three PCRs with the following enzymes: FokI (identifies the normal variant, YMDD, and the mutant variant YVDD), SspI (identifies the mutant variant, YIDD) and Alw44I (identifies the variant, YVDD). The digested fragments were separated by electrophoresis in 3% agarose gel. Of the 139 serum samples analysed, the wild-type YMDD sequence was detected in 106 (76%), the YVDD variant in 20 (15%) and the YIDD variant in 13 (9%) cases. The non-mutated variant, YMDD, was detected in all the pre-treatment samples. After 9 months of treatment the mutant variant was detected in four of 37 serum samples analysed (11%) (two YVDD and two YIDD). At 12 months, 12 of the 37 serum samples (32%) showed mutations in the YMDD sequence (seven YVDD and five YIDD). Among the 16 serum samples obtained at 18 months, nine had the YMDD variant (56%) (seven YVDD and two YIDD). At 24 months, variants in the YMDD sequence were detected in eight of the 12 patients treated (66%) (four YVDD and four YIDD). HBV genotypes were confirmed by direct sequencing, with consistent results. In 45% of cases, the emergence of HBV variants was not associated with ALT breakthrough. The PCR-RFLP assay used in this study, in perfect concordance with direct sequencing, is an accurate method for genotyping lamivudine-resistant HBV variants. Since it is a rapid low-cost technique, PCR- RFLP is suitable for large-scale screening of these polymorphisms in clinical samples.

IgE antibody response to vertebrate meat proteins including tropomyosin

BACKGROUND

Although meat is a main source of proteins in western diets, little information is available regarding allergy to vertebrate meats or the allergens implicated in these reactions.

OBJECTIVE

To evaluate the in vitro IgE antibody response to different vertebrate meats in suspected meat-allergic subjects, as well as the possible role of tropomyosin in meat allergy and to analyze the cross-reactivity between vertebrate meats and the effect of heating on the IgE-binding to meat proteins.

METHODS

Fifty-seven sera from suspected meat-allergic subjects were tested by grid blot to extracts of beef, lamb, pork, venison, chicken, and turkey and to four mammalian tropomyosins of different origins.

RESULTS

Meat-allergic subjects have IgE antibodies to proteins in different mammalian meats (43/57 subjects); cross-reactivity with avian meat was limited: less than 50% (19/43) of meat positive sera reacted to chicken. In contrast, most of the poultry-positive sera also reacted to different mammalian meats. In general, there was stronger IgE reactivity to raw meats in comparison to cooked meats; an exception was six cases in which IgE reactivity to cooked poultry was stronger. Weak IgE reactivity to tropomyosin was detected in only 2/57 sera tested.

CONCLUSIONS

Suspected meat-allergic subjects have serum IgE directed to meat proteins. In vitro cross-reactivity among mammalian meats appears to be important, while cross-reactivity to poultry is limited indicating mammalian-specific proteins. Although cooking in general denatures meat proteins rendering them less allergenic, in some cases the process of cooking may result in the formation of new allergenic moieties. The muscle protein tropomyosin is not an important vertebrate meat allergen.

Actinomyces bowdenii sp. nov., isolated from canine and feline clinical specimens

Four strains of a previously undescribed Actinomyces-like bacterium were isolated from canine and feline clinical specimens. Phenotypic studies indicated the strains were members of the genus Actinomyces, and most closely resembled Actinomyces viscosus serotype I and Actinomyces slackii. Comparative 16S rRNA gene sequencing studies demonstrated the unknown bacterium constitutes a new subline within a group of Actinomyces species, which includes Actinomyces bovis, the type species of the genus. Based on phylogenetic and phenotypic evidence it is proposed that the unknown bacterium be classified as Actinomyces bowdenii sp. nov. The type strain of Actinomyces bowdenii is CCUG 37421T.

Brevibacterium avium sp. nov., isolated from poultry

Two strains of a Brevibacterium-like bacterium originating from bumble-foot lesions of domestic fowls were subjected to a polyphasic taxonomic study. The phenotypic characteristics of the bacterium were consistent with its assignment to the genus Brevibacterium although comparative 16S rRNA gene sequencing showed that the organism represents a distinct subline within the genus. Chromosomal DNA-DNA pairing studies confirmed that the unidentified bacterium was genomically distinct and worthy of separate species status. Based on the phenotypic and genotypic distinctiveness of the bacterium from poultry, a new species, Brevibacterium avium, is proposed. The type strain of Brevibacterium avium is NCIMB 703055T.

Glycosylphosphatidylinositol-specific phospholipase D in blood serum: is the liver the only source of the enzyme?

In cases of systemic inflammatory response syndrome, sepsis, and septic shock, the activity of glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) in serum amounts to 20 to 25% of the activity found in a healthy control group. The activity of serum GPI-PLD is positively correlated with inflammatory markers and counts of monocytes and stab cells (bands) and negatively correlated with polymorphonuclear neutrophils and lymphocytes in severe diseases. This indicates a yet unknown involvement of the inflammatory system in GPI-PLD liberation and suggests that the liver is not the only source of the plasma enzyme. Plasma was shown to contain an effective inhibitor of GPI-PLD which is soluble in organic solvents. Its concentration in capillary plasma is 20-fold higher than in venous plasma. To find possible other sources of plasma GPI-PLD besides the liver, the GPI-degrading activity was measured in different organs of the rat. Product formation was analysed using [125I]TID-labeled GPI-AP.

Effect of antioxidants on induction time of luminol luminescence elicited by 3-morpholinosydnonimine (SIN-1)

The reaction between luminol as a chemiluminescence probe and 3-morpholinosydnonimine (SIN-1) as a peroxynitrite donor was evaluated in order to determine the action of several antioxidants. Several well-known antioxidants found in biological fluids or cells modify the light profile of the reaction between SIN-1 and luminol. One main modification was characterized by a transient suppression of the light signal, thus permitting evaluation of an induction time (sigma) which is linearly related to the concentration of the additive. From induction time measurements and using Trolox as a reference antioxidant, the trapping ability of a compound against oxidants and radicals produced in the luminol-SIN-1 reaction at pH 7. 4 was determined. Uric acid showed higher antioxidant capacity than Trolox, while bilirubin and ascorbic acid, in decreasing order, were slightly less efficient. On the other hand the main modification of the light signal produced by superoxide dismutase, desferrioxamine and myoglobin was characterized by a decrease of the luminescence during the course of the reaction. The reaction luminol-SIN-1 was compared with the known luminol-ABAP (2,2'-azo-bis-2-amidinopropane) method for evaluation of antioxidant capacity in human plasma, since this biological fluid modifies the luminol-SIN-1 reaction with well-defined induction times. Samples were obtained from patients with sepsis, a condition where it has been postulated that excess oxygen radicals including peroxynitrite are produced. Using Trolox as reference, the results (mean +/- standard error of mean) of both assays showed that the patients (SIN-1, 263 +/- 16; ABAP, 218 +/- 13; n = 19) have significantly (SIN-1, p < 0.02; ABAP, p < 0.001) lower values in comparison to non-septic controls (SIN-1, 330 +/- 16; ABAP, 398 +/- 16; n = 20). SIN-1 could be useful as a source of oxidant for the characterization of antioxidant behaviour in a system where superoxide and nitric oxide are simultaneously generated.

Phenotypic and phylogenetic characterization of a novel Lactobacillus species from human sources: description of Lactobacillus iners sp. nov

Eleven strains of a hitherto undescribed Gram-positive, catalase-negative, facultatively anaerobic rod-shaped bacterium from human sources and medical care products were characterized by phenotypic and molecular taxonomic methods. The phenotypic properties of the bacterium were consistent with its assignment to the genus Lactobacillus but it was readily distinguished from all currently described species of this genus by its biochemical characteristics and by SDS-PAGE analysis of its cellular proteins. Comparative 16S rRNA gene sequence analysis demonstrated that the unknown bacterium was a member of rRNA group I Lactobacillus which includes Lactobacillus delbrueckii, the type species of the genus, and close relatives. Lactobacillus gasseri and Lactobacillus johnsonii were the nearest phylogenetic relatives of the unknown bacterium, but 16S rRNA sequence divergence values of > 4% clearly showed that it represents a distinct species. Based on both phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium should be classified in the genus Lactobacillus, as Lactobacillus iners sp. nov. The type strain of Lactobacillus iners is CCUG 28746T.

Effect of plasma and LPS on respiratory burst of neutrophils in septic patients

OBJECTIVE

To compare the respiratory burst of neutrophils in sepsis and control patients using lipopolysaccharide (LPS), autologous plasma, and a combination of the two.

DESIGN

Prospective, consecutive case study.

SETTING

A 16-bed intensive care unit (ICU) in a university teaching hospital.

INTERVENTIONS

None.

PATIENTS

Plasma was obtained from 23 healthy patients scheduled for minor surgery immediately prior to induction of anesthesia (controls) and from 23 ICU patients within 24 h of diagnosis of sepsis or septic shock.

MEASUREMENTS AND MAIN RESULTS

Respiratory burst was determined by lucigenin chemiluminescence expressed as mean +/- SEM of peak values of relative light units per neutrophil. There were no significant differences between neutrophils of septic patients and controls for the stimuli saline, phorbol myristate acetate, formyl-methionyl-leucyl-phenylalanine, and LPS alone. Septic patients showed a lower respiratory burst than controls (p < 0.05) under the following stimuli: plasma alone (5911 +/- 803 vs 15,397 +/- 3038) and LPS and plasma combined (13,857 +/- 1537 vs 23,026 +/- 2640). However, when stimulated with plasma after priming with LPS, septic patients elicited a higher value than control subjects (11,373 +/- 1758 vs 5987 +/- 1234, p < 0.05).

CONCLUSIONS

(1) Some components of the plasma of septic patients may have a profound effect on neutrophil response; (2) plasma as a respiratory burst stimulus differentiates between sepsis and non-sepsis samples better than other common stimuli; (3) precautions must be taken when using plasma together with LPS because of the different response depending on whether LPS-priming precedes the plasma stimulus or both are introduced simultaneously and whether septic or nonseptic plasma is used.

Hyperinsulinaemia, dyslipaemia and cardiovascular risk in girls with a history of premature pubarche

Girls with a history of premature pubarche, i.e. appearance of pubic hair before 8 years of age, show hyperinsulinism in response to an oral glucose tolerance test. As hyperinsulinaemia has a major role in dyslipaemia, and is considered an independent risk factor for cardiovascular disease, we assessed the patterns of plasma insulin concentration after a standard oral glucose tolerance test as well as fasting serum lipid, lipoprotein, and sex hormone-binding globulin concentrations in girls (n = 81) with premature pubarche compared with girls (n = 55) matched with them for stage and bone age to ascertain their metabolic states to identify those potentially at risk for the development of premature cardiovascular disease. Mean serum insulin concentrations were higher in patients at all pubertal stages, and associated with elevated serum triglyceride, very low density cholesterol and very low density triglyceride concentrations (p value range 0.04 to < 0.0001) but reduced sex hormone-binding globulin. Premature pubarche patients also displayed higher low density to high density lipoprotein cholesterol ratios compared with control subjects (p = 0.004 to 0.008). In conclusion, hyperinsulinaemia, decreased sex hormone-binding globulin concentrations and an unfavourable lipid pattern are common features in premature pubarche girls supporting the contention that atherogenic abnormalities composing the metabolic syndrome could start in childhood. To determine the clinical sequelae of such clustering of metabolic deviations, girls who were identified need to be followed up for the potential development of premature cardiovascular disease.

[Quantitative determination of HBV-DNA in chronic hepatitis B: comparison of three methods]

The aim of this study was to evaluate a technique of quantitative determination of DNA-HBV in serum, bDNA Quantiplex, in a series of 90 patients with chronic HBV infection: 75 with chronic hepatitis B (24 HBeAg positive and 51 with anti-HBe) and 15 asymptomatic carriers of HBV (anti-HBe positive). The results were related to DNA-HBV determination by hydridation techniques in dot-blot and PCR. DNA-HBV was detected by the Quantiplex bDNA technique in 61 (81%) of the 75 patients with chronic hepatitis B, in 24 (100%) of the 24 HBeAg positive patients and in 37 (72%) of the 51 anti-HBe positive (p < 0.05) patients and in none of the asymptomatic HBV carriers. The median of DNA-HBV concentration was 4,000 pg/ml in the hepatitis HBeAg and 71 pg/ml in the ati-HBe positive (p < 0.05). A significant relation was observed between the ALT value and the DNA-HBV concentration (p < 0.05). DNA-HBV by dot-blot was positive in 22 (29%) of the chronic hepatitis B and in none of the asymptomatic HBV carriers. DNA-HBV was not observed by dot-blot in 39 patients positive for DNA-HBV by the Quantiplex bDNA technique. DNA-HBV by PCR was identified in 65 (87%) of the chronic hepatitis B and in one of the asymptomatic HBV carriers. The sensitivity of the Quantiplex bDNA technique (98% versus the PCR technique) is much greater than that observed with dot-blot. In conclusion, the determination of DNA-HBV by the Quantiplex bDNA technique may be considered a good method for evaluating the viremia and degree of viral replication in patients with chronic hepatitis B.

Amphotericin B determination in respiratory secretions by reversed-phase liquid chromatography

Direct delivery of amphotericin B (AMB) to the respiratory tract may be an alternative to intravenous administration. The use of inhalation allows high AMB concentrations to be achieved at the site of infection. A reversed-phase high-performance liquid chromatographic method with a 30-mm-long column is described for assaying AMB in respiratory secretions obtained by bronchoaspiration (BAS) and bronchoalveolar lavage (BAL). Sample clean-up involved treatment with methanol (BAS) and solid-phase extraction onto Sep-Pak C18 cartridges (BAL). The mobile phase consisted of 2.5 mM Na2EDTA-acetonitrile (70:30, v/v). The retention time of AMB was 1.5 min. The range of the assay was from 0.1 to 5 micrograms/ml. The mean recovery was over 90% for both fluids. Within-day and between-day RSDs ranged from 3.10 to 11.87%. AMB in the BAS samples was stable for two days at 20-25 degrees C and for three months at -20 degrees C. The drug in the BAL fluid was stable for one day at 20-25 degrees C, seven days at 4 degrees C and for one month at -20 degrees C.