Characterization ofHaemophilus influenzae isolated from patients with otitis media

Dabernat, H.; Delmas, Catherine; Rich, C; Livrelli, Valérie; Joly, B

doi:10.1007/bf01963092

Cited by 3 publications

(3 citation statements)

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“…Teng et al (1989) reported that biotype III has a higher incidence of ampicillin resistance among the different biotypes. Dabernat et al (1988) reported that 50 % of encapsulated-type strains were biotype I, and often resistant to ampicillin (38?5 %), while 42 % of nonencapsulated strains were of biotype II with 10?6 % resistant to ampicillin. Granato et al (1983) also reported that encapsulated strains of biotype I had the highest frequency of ampicillin resistance.…”

Section: Resultsmentioning

confidence: 99%

High ampicillin resistance in different biotypes and serotypes of Haemophilus influenzae colonizing the nasopharynx of healthy school-going Indian children

Jain¹,

Kumar²,

Awasthi³

2006

Journal of Medical Microbiology

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Haemophilus influenzae is one of the main causes of otitis media, sinusitis, meningitis, pneumonia and septicaemia in children, and the development of ampicillin resistance in H. influenzae is a cause of serious concern. The aim of the present study was to determine the prevalence of ampicillin resistance in H. influenzae colonizing the nasopharynx of school-going healthy North Indian children, and to compare the distribution of different biotypes and serotype b in this population. A total of 2400 school-going healthy children from 45 rural and 45 urban schools were enrolled. Nasopharyngeal swabs were collected from the children and cultured. H. influenzae was isolated from 1001 (41?7 %) of the 2400 nasopharyngeal swabs collected. All these H. influenzae isolates were biotyped and serotyped, and their antibiotic susceptibility tested. All eight biotypes were present in this population. The most prevalent biotypes were I (19?6 %), II (16?8 %) and III (25?0 %). Of the 1001 isolates, 316 (31?6 %) were H. influenzae type b and 685 (68?4 %) were non-type b H. influenzae, and 22?9 % were resistant to ampicillin, 41?9 % to chloramphenicol, 27?5 % to erythromycin and 67?3 % to co-trimoxazole. Of the 316 H. influenzae type b isolates, 44?0 % were ampicillin resistant, while only 13?1 % non-type b H. influenzae isolates were ampicillin resistant. Of the 229 ampicillin-resistant H. influenzae isolates, 196 (85?6 %) were positive for b-lactamase; 93?4 % (214/229) were biotypes I, II and III, of which 49 % were biotype I, 27?9 % were type II and 16?6 % were type III. Most of the strains belonging to biotypes III-VIII were ampicillin sensitive. Ampicillin resistance is significantly more common in biotype I and serotype b than in other biotypes and serotypes. INTRODUCTIONHaemophilus influenzae asymptomatically colonizes the nasopharynx of healthy individuals, and causes systemic disease and mucous membrane infections. Eight biotypes and six serotypes are used as epidemiological markers for studying the pattern of colonization of H. influenzae and to identify the strains of bacterium commonly known to be pathogenic (Alrawi et al., 2002). For instance biotype I and serotype b are commonly associated with meningitis in children, and biotypes II and III are commonly associated with upper respiratory tract infections (Pittman, 1931;Kilian, 1976;Gratten, 1983).Ampicillin/amoxycillin was the empirical treatment for Haemophilus disease until the recent past. Development of ampicillin resistance in causative organisms led to use of third-generation cephalosporins (e.g. ceftriaxone) as empirical drugs. Resistance to ampicillin results from the production of a b-lactamase and alteration of the antibiotic target, penicillin-binding protein (Markowitz, 1980;Mendelman et al., 1984). Treatment problems linked to the prevalence of b-lactam resistance are compounded by the frequency of cross resistance to many other antibiotics (Talon et al., 2000). The high cost of cephalosporins and the development of drug resistance due to irrational use...

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Section: Resultsmentioning

confidence: 99%

High ampicillin resistance in different biotypes and serotypes of Haemophilus influenzae colonizing the nasopharynx of healthy school-going Indian children

Jain¹,

Kumar²,

Awasthi³

2006

Journal of Medical Microbiology

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“…Although the majority (90%) of cases of H. influenzae-induced AOM are due to NTHi strains, Hib strains are reported to cause AOM in 10% of cases (8). We have shown that AOM can be induced experimentally in rats both by NTHi and by Hib strains (27).…”

Section: Discussionmentioning

confidence: 68%

“…The Haemophilus influenzae capsular polysaccharide, polyribosyl ribitol phosphate (PRP), plays a major role in determining the types of infections caused by this organism. Unencapsulated H. influenzae strains are responsible primarily for mucosal infections, such as otitis media, sinusitis, pneumonia, and pharyngitis (12,31,35), whereas encapsulated strains cause more invasive diseases, such as meningitis, epiglottitis, suppurative arthritis, cellulitis, and otitis media (8,28). Currently available H. influenzae type b (Hib) vaccines have been shown to be effective only against infections caused by Hib.…”

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confidence: 99%

The acylated form of protein D of Haemophilus influenzae is more immunogenic than the nonacylated form and elicits an adjuvant effect when it is used as a carrier conjugated to polyribosyl ribitol phosphate

et al. 1997

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The nonacylated form of protein D (PDm) of Haemophilus influenzae has been shown to induce the production of antibodies that are bactericidal to homologous and heterologous nontypeable H. influenzae (NTHi) strains. In this study, immunization of rats with lipoprotein D (LPD) induced higher levels of anti-protein D immunoglobulin G and A serum antibodies than immunization with PDm, and the bactericidal activities of sera from LPD-immunized rats were greater than those of sera from PDm-immunized rats. Immunization with LPD or PDm did not prevent the development of acute otitis media (AOM) when rats were challenged with 10 4 CFU of an NTHi strain. However, on the eighth day of bacterial challenge, 50% (5 of 10) of LPD-immunized rats had recovered from otitis media and 30% (3 of 10) had negative middle ear cultures, whereas only 30% (3 of 10) of PDm-immunized rats had recovered, though none was culture positive. Immunization with an inactivated homologous bacterial strain elicited 70% protection (i.e., 7 of 10 rats) in the rat otitis media model. LPD and PDm were also conjugated to the H. influenzae type b (Hib) capsular polysaccharide, polyribosyl ribitol phosphate (PRP), to test protein D-conjugated PRP vaccine's potential for protection against Hib infection. When two LPD-conjugated and two PDm-conjugated PRP vaccines, each containing a different protein concentration, and a tetanus toxoid-conjugated vaccine (ACT-HIB) were tested in the experimental model of rat otitis induced with a Hib strain (Minn A), both of the LPD-conjugated and one of the PDmconjugated vaccines induced significant protection from AOM, the level of protection being highest in animals given the vaccine with the highest LPD content. Sera from these rats also manifested the highest anti-PRP and anti-LPD antibody levels and the highest bactericidal activities against a Hib strain and an NTHi strain.

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Type B haemophilus influenzae—induced otitis media in the mouse

et al. 1991

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To characterize the middle and inner ear cellular inflammatory responses to otitis media using immunohistochemical methods, we inoculated type B Haemophilus influenzae into the middle ears of healthy adult BALB/c mice. Mac-1+ neutrophils and macrophages appeared in the middle ear at 3 days. Lyt-1+ T cells and Lyt-2+ T suppressor/cytotoxic cells entered the middle ear mucosa on days 7 and 14. IgG+ and IgM+ T cells were present at all time points, with IgA+ lymphocytes forming the majority of mucosal immunoglobulin-bearing cells at 2 weeks. The cochlear scala tympani contained Lyt-1+ and Mac-1+ cells and two endolymphatic sacs stained diffusely with anti-IgA and -IgG antibodies. Lyt-1/L3T4+ T lymphocytes greatly outnumbered B lymphocytes, suggesting that helper/inducer T cells play a more important role in acute otitis media than has been recognized. Inner ear changes occurred after a single episode of otitis media.

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Characterization ofHaemophilus influenzae isolated from patients with otitis media

Cited by 3 publications

References 42 publications

High ampicillin resistance in different biotypes and serotypes of Haemophilus influenzae colonizing the nasopharynx of healthy school-going Indian children

High ampicillin resistance in different biotypes and serotypes of Haemophilus influenzae colonizing the nasopharynx of healthy school-going Indian children

The acylated form of protein D of Haemophilus influenzae is more immunogenic than the nonacylated form and elicits an adjuvant effect when it is used as a carrier conjugated to polyribosyl ribitol phosphate

Type B haemophilus influenzae—induced otitis media in the mouse

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