A taxonomic study of the genus Haemophilus, with the proposal of a new species

The nasopharyngeal microflora of otitis-prone children, with emphasis on H. influenzae

The nasopharyngeal microflora was monitored during a prospective study of 52 otitis-prone children and 33 age-matched controls up to the age of 30 months. The relation between nasopharyngeal culture results and corresponding otoscopic findings was investigated. In contrast to pneumococci, the rate of H. influenzae isolation was correlated to the degree of otologic disease, thus it was found more often in connection with AOM than with a normal otologic status, with OME in an intermediate position. Also in contrast to pneumococci, in children with AOM, H. influenzae was commoner in the otitis-prone group than in the control group. H. influenzae biotype II was found in 77% in association with AOM in the control group. In the otitis-prone group the difference in frequency of biotypes I, II and III causing AOM were less pronounced. Turnover of H. influenzae strains as judged by change in biotype was found to occur more often in connection with treatments with penicillin-V than treatments with amoxicillin.

Nucleotide sequence homology between the immunoglobulin A1 protease genes of Neisseria gonorrhoeae, Neisseria meningitidis, and Haemophilus influenzae

Isolated DNA fragments encoding the immunoglobulin A1 (IgA1) protease of Neisseria gonorrhoeae were used as hybridization probes to search for homologous sequences in whole cell DNA from Neisseria meningitidis and Haemophilus influenzae. Significant homology was detected. That the detected homology represented IgA1 protease-specific sequences was confirmed by the cloning of these sequences in Escherichia coli HB101 and demonstrating the expression of IgA1 protease by these transformed cells. Molecular probing of commensal Neisseria and Haemophilus species, which do not elaborate IgA1 protease activity, revealed that they were devoid of sequence homology with the cloned IgA1 protease gene DNA.

Epidemiology of chancroid and Haemophilus ducreyi in Nairobi, Kenya

Of 300 men in Nairobi, Kenya, with culture-proven chancroid, 57% had acquired infection from prostitutes. The majority of infections were acquired in the city of Nairobi. All 10 female source contacts examined had genital ulcers. 13 of 29 female secondary contacts were culture-positive for Haemophilus ducreyi and 10 of these infected women had clinical chancroid. Of 122 prostitutes from the middle and lower social strata, 12 had genital ulcers, 5 of which were culture-positive for H ducreyi, and a further 5 had symptomless genital carriage of H ducreyi. Prostitutes are a major reservoir of H ducreyi in Nairobi. No evidence of transmission of H ducreyi by women without clinical chancroid was detected.

Occurrence of Haemophilus influenzae strains in children with respiratory tract infections

In the time period from February 1980 to October 1981, 179 children with upper respiratory tract infections and 67 healthy controls were investigated in Warsaw. The clinical condition of the studied children, the types of the obtained H. influenzae strains and their sensitivity to the antibiotics and sulphamides used most frequently in clinical practice were analyzed.

Development of a test system for rapid differentiation of Neisseria and Haemophilus spp

A qualitative micromethod (IDS Rapid NH system) employing conventional and single-substrate enzyme tests was developed for the biochemical characterization of Neisseria spp., Haemophilus spp., and other gram-negative species. A total of over 140 dehydrated, miniaturized biochemical tests were investigated for their ability to distinguish species. Computer-assisted test selection and pair separation analysis of the data allowed the selection of 11 4-h tests that would identify Haemophilus and Neisseria spp. implicated as etiological agents as well as differentiate them from other Neisseria spp., Moraxella spp., Branhamella catarrhalis, Centers for Disease Control M groups, and Kingella spp. The final test configuration included modified glucose, sucrose, galactosidase, nitrate, phosphatase, resazurin reduction, and two arylamidase tests. In addition, indole, urea, and ornithine decarboxylase tests were included to biochemically type strains of Haemophilus influenzae and Haemophilus parainfluenzae.

Antigenic heterogeneity of immunoglobulin A1 proteases from encapsulated and non-encapsulated Haemophilus influenzae

Indirect evidence suggests that immunoglobulin A1 (IgA1) proteases may be factors in the pathogenesis of certain infectious diseases, including meningitis, gonorrhoea, and destructive periodontitis. Bacterial IgA1 proteases are therefore potential candidates as vaccines. In this study, IgA1 proteases from 166 clinical isolates and reference strains of Haemophilus influenzae and Haemophilus aegyptius were compared with regard to specific activity and pattern of enzyme inhibition by antisera raised against IgA1 protease from nine selected strains of H. influenzae. A total of 93% of H. influenzae strains and all H. aegyptius strains had detectable IgA1 protease activity. The majority of strains cleaved a prolyl-seryl or a prolyl-threonyl peptide bond in the alpha 1 hinge region, whereas occasional H. influenzae strains possessed two separate IgA1 proteases with these two specific activities. Of the 155 IgA1 protease-producing strains, all except 12 could be assigned to one of 14 IgA1 protease "inhibition types," each defined by a characteristic pattern of inhibition by the nine antisera. There was no correlation between IgA1 protease type and biotype of the strains. However, among 92 encapsulated H. influenzae strains, a close correlation between capsular serotype and IgA1 protease type was observed. With the exception of serotype f, strains of all capsular serotypes produced an exclusive antigenic type of IgA1 protease. All 38 strains of serotype b produced IgA1 protease of inhibition type 1, which was never demonstrated in non-encapsulated H. influenzae strains. These results facilitate the detection of an antibody response against specific IgA1 proteases and are of practical value for a possible future vaccine against H. influenzae serotype b infections.

Haemophilus influenzae biotype VII

A hitherto unreported biotype of Haemophilus influenzae is described. The isolate is noncapsulate and fails to decarboxylate ornithine or hydrolyze urea but is a strong indole producer. Its frequency is low. It is suggested that this newly recognized biotype of H. influenzae be designated biotype VII.

Comparison of outer membrane protein subtypes of Haemophilus influenzae type b isolates from healthy children in the general population and from diseased patients

Over a 12-month period we obtained throat cultures from 1,448 children less than 5 years of age attending well-child clinics and identified 24 carriers of Haemophilus influenzae type b (1.7%). The outer membrane protein subtypes of the strains from the carriers were compared to the subtypes of isolates from 50 patients with Haemophilus type b disease hospitalized in St. Louis, Mo., during the same period (1981 to 1982), and the latter were compared to the subtypes of isolates from 51 patients hospitalized between 1977 and 1980. There were no significant differences in the frequencies of the five most common subtypes (1L, 1H, 2L, 2H, and 3L), comparing isolates from the carriers to those from the patients. However, 5 of the 24 throat isolates had the unusual 13L subtype compared with only 1 of the 50 invasive isolates (P = 0.02). The lower frequency of 13L strains among the invasive isolates suggests that type b isolates with this subtype may be less pathogenic than type b isolates with other subtypes. Subtype 2L strains accounted for only 2% of recent cerebrospinal fluid or blood isolates, compared with 22% of those from 1977 to 1980 (P = 0.02). Subtype 1H and 3L strains together accounted for 73%, compared with 47% of the earlier ones (P = 0.02). Thus, temporal shifts may also occur in the subtype distribution of Haemophilus type b strains causing invasive disease in a community.

Nasopharyngeal flora and acute otitis media

A semiquantitative nasopharyngeal culture was found to be sensitive and specific in predicting middle ear pathogens in children with acute bacterial otitis media. In nasopharyngeal specimens with growth of at least 1,000 colonies, the tympanocentesis isolate was present and was either the predominant isolate or accounted for 50% of growth in 16 of 16 children. Data suggest that virulence of nasopharyngeal organisms plays a role in the pathogenesis of acute otitis media. Qualitative differences were found in the nasopharyngeal flora of children with bacterial otitis media as compared with children with clinical otitis media and sterile tympanocentesis cultures, children with uncomplicated upper respiratory illness, and healthy children. Abundant growth of Haemophilus influenzae (greater than or equal to 50% total colony count) was associated with children with bacterial otitis media, and abundant Branhamella catarrhalis was associated with the others (P less than or equal to 0.01). Abundant growth of Streptococcus pneumoniae occurred frequently and regardless of clinical category. Antibiotic treatment of children with otitis media resulted in rapid quantitative and qualitative changes in nasopharyngeal flora.

Rapid species identification and biotyping of respiratory isolates of Haemophilus spp

Three commercially available systems, the 4-h Minitek Enterobacteriaceae III, the Haemophilus Trio-Tube, and the Micro-ID, were evaluated for their capacities to identify and biotype 308 respiratory isolates of Haemophilus spp. When compared with aminolevulinic acid test results, the definitive identification method used in this study, these systems demonstrated no significant differences in their capacities to differentiate Haemophilus influenzae from Haemophilus parainfluenzae. They were in agreement with the standard method of species identification approximately 50% of the time. When sucrose was added to the Minitek and Trio-Tube configurations, the efficiency rate of species identification increased to more than 95%. The Micro-ID could not be modified to incorporate this additional biochemical parameter. The performance of the sucrose-supplemented Minitek and Trio-Tube systems, compared to the combined results of Micro-ID and aminolevulinic acid, produced correlations of 94 and 90%, respectively. Rapid and accurate methodologies are available for combined species identification and biotyping of Haemophilus spp.

Molecular biology of Haemophilus influenzae IgA1 proteases

IgA1 proteases of two distinct specificities were demonstrated among 95 isolates of Haemophilus influenzae and nine isolates of H. aegyptius. The two enzymes cleaved two different peptide bonds in the hinge region of the alpha chain of IgA1: a prolyl-seryl bond located at position 231-232 (type A cleavage) and a prolyl-threonyl peptide bond between residues 235 and 236 (type B cleavage). Each strain of H. influenzae produced either one or both of these types of enzymes, whereas all H. aegyptius strains produced type A enzyme only. The application of enzyme-neutralizing antibodies to the study of IgA1 proteases produced by the 104 strains of H. influenzae and H. aegyptius revealed at least 15 different types of protease activities based on inhibition patterns in nine selected antibody preparations. The types of IgA1 proteases closely correlated with the serotype of encapsulated strains of H. influenzae. The study suggests that H. influenzae strains produce at least two serologically different IgA1 proteases with distinct or identical enzymatic activities.

Primary peritonitis due to Haemophilus influenzae type b in a previously healthy child

A case of primary peritonitis caused by Haemophilus influenzae type b biotype 2 in a 3-year-old child is described. The organism was isolated from peritoneal fluid. This is the first case of documented peritoneal infection due to this species in a patient who showed no evidence of being immunocompromised.

Pneumonia and bacteremia associated with Haemophilus influenzae serotype d

Haemophilus influenzae serotype d was isolated from three women with pneumonia and underlying cardiopulmonary disease. Two of the strains were isolated from blood, and the third strain was isolated from sputum. The biotypes of the isolates were I, IV, and VI.

Evaluation of some methods for the laboratory identification of Haemophilus influenzae

Five tests--satellitism, synthesis of porphyrins, acid production from sucrose, beta-galactosidase activity (ONPG), and indole production--to differentiate between strains of Haemophilus influenzae and strains of V-dependent Haemophilus species were evaluated. Six per cent of strains of H influenzae were misidentified as H parainfluenzae by a test for satellitism using filter paper discs impregnated with X factor, V factor, or both, applied to Columbia Agar. None of seven nutrient agars tested grew Haemophilus species, and determined accurately the X factor requirement. Synthesis of porphyrins from delta-aminolaevulinic acid provided a reliable means of demonstrating that X factor was required. A test for the production of acid from sucrose discriminated successfully between strains of V-dependent Haemophilus species (positive) and H influenzae (negative). Most isolates were identified correctly by the ONPG test, but occasional V-dependent strains were negative and could be misidentified as H influenzae. The discriminative value of the indole test was unsatisfactorily low. The results of the tests are discussed in relation to the identification of H influenzae in the diagnostic laboratory.

Treatment of chancroid with erythromycin. A clinical and microbiological appraisal

One hundred and thirty seven patients presenting with genital ulcerations from which Haemophilus ducreyi was isolated were treated with erythromycin stearate 500 mg every six hours for seven days. Of these, 91 (66%) had associated inguinal lymphadenopathy. Only two of the 100 patients who returned after one week showed no clinical improvement. Despite decrease in size H ducreyi was reisolated from the ulcers of three patients, two of whom had not complied with treatment. The patients were treated for a further week either with erythromycin or with a placebo preparation and on day 14 no discernible difference in clinical response was evident. H ducreyi was not reisolated from any lesion. In contrast, the natural course of development of associated lymphadenopathy was not modified by treatment. H ducreyi was not, however, isolated from any gland after the start of treatment. Side effects attributable to erythromycin were minimal and treatment had to be discontinued in only two patients. This study clearly indicates that treatment with erythromycin for one week results in rapid healing of lesions and the elimination of H ducreyi from both ulcers and associated lymph glands.

Characteristics of major outer membrane proteins of Haemophilus influenzae

Several properties of Haemophilus influenzae outer membrane proteins were analyzed to define related proteins in various isolates. H. influenzae type b 760705 had six major outer membrane proteins with the following characteristics. Protein a (Mr, 47,000) demonstrated heat modifiability in sodium dodecyl sulfate; its apparent molecular weight was 34,000 at temperatures below 60 degrees C. This protein was extracted from cell envelopes by using Triton X-100-10 mM MgCl2; in cell envelope preparations, the protein was degraded by trypsin. Proteins b (Mr, 41,000) and c (Mr, 40,000) were insensitive to trypsin degradation, were not heat modifiable in sodium dodecyl sulfate, and were peptidoglycan associated in 0.5% Triton X-100-0.2% sodium dodecyl sulfate. The amount of protein b was reduced in ultrasonically obtained cell envelopes. Protein d (Mr, 37,000) was heat modifiable in sodium dodecyl sulfate with an Mr of 28,000 at temperatures below 100 degrees C and was degraded by trypsin, leaving a membrane-bound fragment of Mr, 27,000. Both the intact and degraded proteins were immunologically cross-reactive with the heat-modifiable OmpA protein of Escherichia coli K-12. Protein d was absent in LiCl-EDTA extracts of cells. Protein e (Mr, 30,000), invariably present in all H. influenzae strains tested, was insensitive to trypsin and absent in LiCl-EDTA extracts of cells. Protein k (Mr, 58,000) was extracted from cell envelopes with 2% Triton X-100-10 mM MgCl2 and, in cell envelopes, appeared to be sensitive to trypsin degradation. Proteins with similar properties to those of proteins a to k were found in 10 other H. influenzae b strains, reference strains with serotype a, c, d, e, and f capsules, and 18 of 20 nonencapsulated strains. Their relative molecular weights, however, varied.

Single-dose therapy of chancroid with trimethoprim-sulfametrole

We conducted a randomized double-blind trial comparing a single dose of trimethoprim-sulfametrole (640 to 3200 mg) with five-day regimens of either trimethoprim-sulfametrole (160 to 800 mg twice daily) or trimethoprim alone (200 mg twice daily) for the treatment of men with chancroid. Of 95 patients, 78 had cultures positive for Hemophilus ducreyi. Twenty-seven, 23, and 28 patients, respectively, were assigned to the single-dose trimethoprim-sulfametrole, the five-day trimethoprim-sulfametrole, and the five-day trimethoprim treatments. The rate of ulcer and bubo resolution, the mean (+/- S.D.) healing times (10.3 +/- 5.7, 11.0 +/- 7.4, and 11.9 +/- 8.2 days, respectively), the microbiologic response, the number of treatment failures, and the number of recurrent ulcers were similar in all three treatment groups. We conclude that single-dose trimethoprim-sulfametrole is a highly effective, inexpensive therapy for chancroid in men and may prove to be an important strategy for the control of H. ducreyi infection.

Dilution technique for isolation of Haemophilus from swine lungs collected at slaughter

A total of 307 lungs obtained from a slaughterhouse were cultured by a dilution technique for the isolation of Haemophilus spp. The technique consisted of performing serial (10-fold) dilutions of the tissue samples to a dilution of 10(-5). Two selective media were used. L broth consisted of a basal brain heart infusion broth containing 5% horse serum, 5% yeast extract, and 100 micrograms of NAD and 0.5 microgram of lincomycin per ml. L-B broth was identical to L broth, except 1.5 microgram of bacitracin per ml was included. The broths were incubated overnight and then plated onto blood agar. A total of 83 (27%) isolates were obtained, and both media proved to be necessary, as a proportion of isolates grew in one of the media employed but not in the other. Of the isolates, 66.3% were urease positive and most of these (98%) were classified as "minor group" strains. Urease-negative strains (27.7%) were classified as Haemophilus parasuis.

Haemophilus influenzae in genitourinary tract infections

Haemophilus influenzae was isolated in pure or predominant culture from genital specimens from nine females and two males. Four of the females had vaginitis, two had IUD-related endometritis, one had an incomplete septic abortion, and one had probable urethral syndrome. Two males had urethritis.

Predominant cultivable microflora of plaque on removable dentures in patients with healthy oral mucosa

Plaque from the fitting surface of upper full dentures in eight patients with healthy palatal mucosa was studied. To characterize the predominant cultivable flora, 916 isolates (100-128 from each sample) were subcultured from anaerobic roll-tubes. Streptococci constituted 0-81 per cent (median, 41 per cent) of the isolates with varying proportions of Streptococcus milleri, Streptoccus mutans, Streptococcus salivarius, Streptococcus mitior and Streptococcus sanguis. Staphylococcus aureus made up 0-13 per cent (median, 6 per cent). Gram-positive rods constituted 1-74 per cent (median, 33 per cent). Among these, Actinomyces israelii, Actinomyces naeslundii, Actinomyces viscosus and Actinomyces odontolyticus were the most common species, whereas lactobacilli were isolated only from two samples, constituting 21 and 48 per cent. Among Gram-negative bacteria, only Veillonella parvula was common, constituting 3-20 per cent (median, 10 per cent). Gram-negative rods were isolated only from three samples in small proportions making up 0-6 per cent (median, 0 per cent) of the flora. Forty-seven isolates (5 per cent) were lost. Cultures for yeasts on Sabouraud agar were positive for five samples and the yeast counts corresponded to 0-0.45 per cent (median, 0.002 per cent) of the total viable counts. The microflora of denture plaque is highly variable and is to a large extent similar to that of some forms of dental plaque.

Biotyping of Haemophilus using API 10S--an epidemiological tool?

One hundred and ninety-nine strains of Haemophilus isolates were biotyped by Kilian's method(1) and a modified API 10S strip and the results compared. One hundred percent correlation was found between the two systems. The ONPG test proved of value in differentiating between Haemophilus influenzae and Haemophilus parainfluenzae when there was growth factor disc failure.

Bacteremic infections caused by nontypable Haemophilus influenzae in patients with dysgammaglobulinemia

Two patients with dysgammaglobulinemia had bacteremic infections due to nontypable Haemophilus influenzae. The regular use of counterimmunoelectrophoresis or the more careful use of existing agglutination techniques to serotype Haemophilus isolates may identify nontypable H. influenzae in this clinical setting more frequently than has been though possible.

Haemophilus ducreyi infections--time for reappraisal

As the literature on Haemophilus ducreyi and clinical chancroid is reviewed, it becomes obvious that many significant findings have been forgotten over the years. As a result, from the time of Ducrey's original description of the organism in 1890 until about 1977, both clinical and laboratory experts in the United Kingdom believed that H. ducreyi infections were rare, generally acquired abroad, and almost impossible to confirm in the routine laboratory! In consequence it was a common view that it was not worth looking for H. ducreyi until all other possible causes of genital ulceration had been excluded. Moreover, the search for such an infection stopped as soon as any other cause for the patient's lesions had been found. A decision to ignore this 'rule' in Sheffield led to our looking for H. ducreyi in specimens from an unselected series of patients with genital ulceration including a number with herpes genitalis infections. The surprise finding of H. ducreyi in circumstances suggesting that it was a secondary invader made us re-examine the whole question of H. ducreyi infections and chancroid and wonder if the same organism can act as a primary pathogen and as a secondary invader. An account of the media and methods we used and of the characteristics of the organism is presented. In an attempt to find out more about the characteristic coherent colonies of H. ducreyi we studied them with the scanning electron microscope. It is clear that the whole subject of H. ducreyi infections has been neglected in the United Kingdom, but we believe that interest has now been aroused and progress will surely follow. Some areas for further investigation are suggested.

Pathogenic microbial flora of genital ulcers in Sheffield with particular reference to herpes simplex virus and Haemophilus ducreyi

The pathogenic microbial flora of genital ulcers in 161 (80 men and 81 women) unselected patients was studied prospectively. In only one case was Treponema pallidum responsible whereas herpes simplex virus was considered to be the cause of 130 (80.8%) genital ulcers. H ducreyi was isolated from 46 (28.6%) patients, most commonly as a secondary pathogen in herpetic lesions. Two or more pathogens were isolated from the ulcers in 67 (41.6%) patients, and in 21 (13%) patients no pathogens were isolated. Our results indicate an urgent need for antiviral treatment to reduce the local reservoir of genital herpes, challenge traditional concepts about the prevalence of H ducreyi in Britain, and call for a reappraisal of its role in the causation of genital ulcers.

Isolation and rapid identification of Haemophilus ducreyi

During a 2-month period, 62 strains of Haemophilus ducreyi were isolated from 168 genital lesions and 2 lymph node aspirates. Of these strains, 22 were found on both chocolate agar and fetal bovine serum agar supplemented with vancomycin, 29 were found only on chocolate agar, and 9 were found only on fetal bovine serum agar. Two additional strains were isolated on sheep blood agar. All of these isolates were correctly identified with the RapID NH system (Innovative Diagnostic Systems, Inc., Decatur, Ga.) a new identification kit that has a database for Haemophilus, Neisseria, and other genera that include fastidious gram-negative bacilli.

Do pili play a role in pathogenicity of Haemophilus influenzae type B?

Surface components of Haemophilus influenzae type b (Hib) responsible for mucosal adherence were identified through assay of in-vitro attachment to human buccal epithelial cells (EC). Among many Hib strains from cerebrospinal fluid, blood, or the nasopharynx (NP), two isolates from NP were found to be exceptionally adherent. Adherence correlated with agglutination of human red blood cells (RBC). The adherent strains displayed pili, not previously described for Hib or other encapsulated H. influenzae. Moreover, highly adherent, piliated subpopulations of bacteria could be selected from any strain, but were lost upon subculture. Thus, the potential to express pili may be general for Hib and may aid the NP colonisation which precedes systemic invasion by this organism. Piliation was correlated with the amount of an outer membrane protein with a molecular weight of about 20,000 daltons, which had proved to be immunogenic in an 8-month-old child.

Antimicrobial susceptibility of 103 strains of Haemophilus ducreyi isolated in Johannesburg

Of 103 strains of Haemophilus ducreyi isolated in Johannesburg, 96 produced beta-lactamase and were resistant to penicillin and ampicillin. Most strains showed resistance to tetracycline, sulfisoxazole, and sulfamethoxazole. All isolates were susceptible to rifampin, erythromycin, and cefoxitin, moderately susceptible to trimethoprim-sulfamethoxazole (1:19) and minocycline, and somewhat less susceptible to doxycycline.

Mutation frequency of Haemophilus influenzae to rifampin resistance

Twenty-two susceptible strains of Haemophilus influenzae were examined for mutation to rifampin resistance (minimal inhibitory concentration, greater than or equal to 10 micrograms/ml). All strains had detectable apparent mutation frequencies with a median minimal inhibitory concentration 2,000-fold greater than that of their wild-type parents. Of the type b strain mutants, 80% (8 of 10) expressed high-level resistance (minimal inhibitory concentration, 750 micrograms/ml) that was 75-fold greater than readily achievable serum concentrations.

Further characterization of Haemophilus paragallinarum and Haemophilus avium

A total of 60 isolates of Haemophilus spp. from chickens, including four reference strains of H. paragallinarum and one of H. avium, were examined for their physiological and biochemical properties. The isolates could be placed into two groups. One group was identified as H. paragallinarum and consisted of 43 isolates including the four reference strains of H. paragallinarum. The other group was identified as H. avium and consisted of 17 isolates including the reference strain of H. avium. H. avium can be differentiated from H. paragallinarum by its possession of the enzymes catalase and alpha-glucosidase, capacity to grow in air, production of acid from galactose, and by the fact that its growth is not improved by the addition of chicken serum. In addition, the majority of H. avium isolates, unlike H. paragallinarum, possess a yellow pigment and produce acid from trehalose.

Methods for the routine characterisation of isolates of Haemophilus

Methods and their evaluation are described for the routine characterisation of Haemophilus spp isolates using a test for dependence on V factor and a test for the conversion of delta-amino-laevulinic acid (ALA) to porphyrin in which the ALA is incorporated into a solid medium. A method is also described whereby the difference in the size of the inhibition zones around discs of ampicillin and of amoxycillin/clavulanate can be used to detect the production of beta-lactamase.

Characteristics of Haemophilus ducreyi. A study

In a study of 13 local and four reference strains of Haemophilus ducreyi all grew well on a selective medium consisting of Bacto proteose No 3 agar (Difco), soluble starch, IsoVitalex, human blood, and vancomycin. All the strains reduced nitrate, were alkaline-phosphatase-positive, and (with one exception) used glucose, fructose, and mannose, beta-lactamase was produced by 12 local strains. Erythromycin was the the most effective antibiotic tested, followed by streptomycin, co-trimoxazole, and spectinomycin.

Novel method of biotyping Haemophilus influenzae that uses API 20e

One hundred Haemophilus influenzae isolates from various body sites were biotyped by conventional methods and by the API 20E system (Analytab Products, Plainview, N.Y.). By using a hemin- and a nicotinamide adenine dinucleotide-enriched saline solution as the inoculating fluid for the API 20E, a 100% correlation of results was obtained between the two methods. Ninety percent of the blood and cerebrospinal fluid isolates were biotype I. Biotype II was the predominant biotype encountered overall. No correlation was observed between beta-lactamase production and biotype. The API 20E is a reliable method and should prove useful for routine biotyping of H. influenzae in the clinical laboratory.

Rapid biotyping of Haemophilus influenzae and Haemophilus parainfluenzae with PathoTec strips and spot biochemical tests

PathoTec strips and spot biochemical tests were evaluated for the ability to biotype Haemophilus influenzae and Haemophilus parainfluenzae. Indole, urease, and ornithine decarboxylase reactions were tested. The results of PathoTec strips compared favorably with those conventional methods; the percent agreements were as follows: indole, 100; urease, 99.5; and ornithine, 95.5. Spot tests were simple and rapid, and the results also compared favorably with those of conventional tests; the percent agreements were as follows: indole, 99; urease, 100; and ornithine, 96.

Outer membrane protein and biotype analysis of pathogenic nontypable Haemophilus influenzae

The techniques of biotype determination and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of outer membrane protein preparations were applied to 35 epidemiologically unrelated isolates of pathogenic nontypable Haemophilus influenzae. Three of five isolates obtained from the blood of unrelated newborns with sepsis had concordant major outer membrane from the blood of unrelated older children or adults with bacteremia had concordant major outer membrane protein profiles, distinct from the common profile of neonatal strains, and were biotype II. The outer membrane protein profiles of the remaining 5 isolates from blood, 2 isolated from cerebrospinal fluid, and 23 isolated from middle ear aspirates of children with otitis media were unique, although each isolate had peptides with apparent molecular weights of 16,000 and 31,500. These results suggest that a subset of nontypable isolates associated with bacteremia has distinctive strain markers. Their pathogenicity may relate to a prediction for colonizing the female genital tract in the case of the common neonatal strain or an increased ability to evade host defenses.

Cellular fatty acid composition of Haemophilus equigenitalis

The cellular fatty acid composition of eight Haemophilus equigenitalis strains was determined by gas-liquid chromatography. All strains showed a grossly similar pattern characterized by large amounts of 18:1 and 16:0. The amounts of 16:1, 18:2, 18:0, 3-OH 14:0, 3-OH 16:0, and 3-OH 18:1 were relatively small.