Haemophilus streptococci

In healthy individuals URT flora multiplies in gastric aspirate during treatment with antisecretory compounds and in particular proton pump inhibitors [34, 40, 44], This concerns viridans streptococci, coagulase-negative staphylococci, Haemophilus sp., diphtheroids, Moraxella sp., lactobacilli, and other streptococci, most of which are Gram-positive bacteria. With dedicated measures anaerobic species of oral origin are also recovered [66]. 

The majority of sepsis cases, especially the more severe forms, have bacterial etiologies. Common bacterial species include Staphylococcus aureus. Streptococcus pneumoniae, Escherichia coli. Salmonella typhi (and other enterobacterial species). Pseudomonas species and haemolytic streptococci in children Haemophilus influenzae and Neisseria meningitidis are important whereas nosocomial episodes of sepsis are frequently caused by Staphylococcus epidermidis. Streptococcus faecalis (syn. enterococci), yeasts and anaerobes. 

Viridans streptococci Neisseria meningitidis Neisseria gonorrhoeae Haemophilus influenzae Escherichia coli Klebsiella Proteus mirabilis Pseudomonas ... 

Streptococci, staphylococci, pneumococci, gonococci, meningococci, Haemophilus influenzae, H. ducreyi, Calymmatobacterium granulomatis. Vibrio comma. Vibrio cholerae, E. coli, Pasteurella pestis. Shigella. 

Azithromycin, though less active against streptococci and staphylococci than erythromycin, is far more active against respiratory infections due to Haemophilus influenzae and Moraxella catarrhalis. Except for its cost, it is now the preferred therapy for urethritis caused by Chlamydia trachomatis. Its activity against Mycobacterium avium intracellulare complex has not proven to be clinically important, except in AIDS patients with disseminated infections. 

An area of increasing concern and clinical importance is the increasing macrohde resistance that has been reported over the last several years with some of the common pathogens, particularly Streptococcus pneumoniae, group A streptococci, and Haemophilus influenzae, and may result in failure of therapy of pneumonia, phar5mgitis, and skin infections (54). High rates of resistance of several groups of streptococci to macrohdes have been reported from all parts of the world (55-64). 

The macrolide antibiotics include erythromycin, clarithromycin, azithromycin, tylosin, tilmicosin and tiamulin. Clindamycin and lincomycin are related lincosamides. Susceptible bacteria include staphylococci, streptococci, Campylobacter jejunii, Clostridium spp., R. equi, Mycoplasma pneumoniae and Chlamydia spp. Drugs in this group are only effective against a few Gram-negative bacteria in cattle, namely some strains of Pasteurella and Haemophilus spp. Macrolides and lincosamides are associated with causing colitis in horses, so their use is usually restricted to p.o. erythromycin for the treatment of R. equi infections in foals. Subantimicrobial doses of erythromycin are administered i.v. to horses for gastrointestinal prokinetic action. 

Staph, aureus and a limited number of Staph, albus, while the nasopharynx is often colonized by streptococci of the viridans group, Strep, salivarius or Neisseria pharynges. Occasionally, pathogens such as Haemophilus influenzae and Klebsiella pneumoniae may be present. The most common organisms secreted during normal respiratory function and speech are saprophytic streptococci of the viridans group. 

Cerebritis is focal inflammation of brain parenchyma myelitis in the spinal cord). Cerebritis precedes abscess formation but requires an early biopsy to be seen (see Tables 20.2 and 20.10). The inflammatory infiltrate is composed of neutrophils, macrophages, lymphocytes, and plasma cells, with or without parenchymal necrosis. Septic cerebritis is usually caused by bacterial agents, most often streptococci or staphylococci, and less commonly by gram-negative organisms, such as Escherichia coli. Pseudomonas, and Haemophilus influenzae. Cerebritis also occurs around neoplasms, ruptured vascular malformations, infarcts, and traumatic lesions. 

It is believed that the lung infection results from impaired mucus clearance followed by colonization of bacteria in the mucus. The bacteria elaborate a number of toxins, polysaccharides, and enzymes including proteases, elastases, and exotoxin A, which may stimulate the production of additional mucus and further contribute to airway obstruction (Sam et al., 1980 Adler et al., 1983). Pseudomonas aeruginosa and Staphylococcus aureus are the most commonly found bacteria in the lungs of patients with CF, but Klebsiella, Esherichia coli, streptococci, and Haemophilus influenza can also be found. Of particular interest is the observation that mucoid strains of infectious bacteria, which are more pathogenic than nonmucoid strains, are most commonly found in patients with CF (Reynolds et al., 1975, 1976). The mucoid strains are also more resistant to phagocytosis by alveolar macrophages and are impermeable to antibiotics because of their mucoid coats. Thus treatment of pulmonary infections in patients with CF can be unusually difRcult. 

Ketolides and macrolides have very similar antibacterial properties. Telithromycin is active against staphylococci, streptococci, S. pneumoniae, Haemophilus spp., Moraxella catarrhalis. Mycoplasma, Chlamydia, and Legionella. It is slightly more active by weight than erythromycin. MIC breakpoints for telithromycin are <0.25 pg/ml for S. aureus, <1 pg/ml for S. pneumoniae, and pg/ml for H. influenzae. 

ANTIBACTERIALACTIVITY Tehthromycin is active against staphylococci, streptococci, S. pneumoniae, Haemophilus spp., Moraxella catarrhalis, mycoplasma, chlamydia, and Legionella. It is slightly more potent than erythromycin. 

E-tests can be used to determine MIC for fastidious organisms such as Streptococcus pneumoniae, P-haemolytic streptococci, Neisseria gonorrhoeae, Haemophilus sp. and anaerobes. It can also be used for non-fermenting Gram-negative bacilli, e.g.. Pseudomonas sp. and Burkholderia pseudomallei. 

---