Gram positive cocci. Staphylococci and streptococci презентация

and by dust. At the reception of a dentist, respiratory infections are one of the most frequently transmitted groups of infections, an aerosol formed during the operation of drills, turbines easily contaminate surrounding objects and enter the respiratory tract.

cocci, which is an extensive group including gram+ and Gram- cocci that cause purulent inflammatory processes of different localization (also called pyogenic).

may occur as single cells or remain attached following cell division

caused by staphylococci. It is characterized by purulent inflammation of any organs and systems with a tendency to progressive spreading, generalization and septic flow.

maxillofacial area, stand out as a cop of microbial associations in abscesses, phlegmon, osteomyelitis and stomatitis. In dental hospitals and private clinics there is often a nosocomial staphylococcal infection after surgical interventions on the dentoalveolar system and the paranasal sinuses.

facultative anaerobes
The Staphylococcus genus includes at least 40 species. Of these, nine have two subspecies, one has three subspecies, and one has four subspecies
Most are harmless and reside normally on the skin and mucous membranes of humans and other organisms
Staphylococci are ubiquitous microorganisms that cause various purulent-inflammatory processes in humans and animals (they are also called pyogenic)

Staphylococcus. The genus includes 27 species, among which there are pathogenic, conditionally pathogenic species and saprophytes. The main human lesions are caused by 3 species: S. aureus, S.epidermidis and S. saprophyticus.

preparations from pure culture they are arranged in the form of disordered clusters resembling bunches of grapes. In smears from pus - singly, in pairs or in small groups. Do not have a dispute, flagella (immovable), can form a gentle capsule.

MORPHOLOGY

dense media form colonies in S-form - round, with an even edge, painted in cream, yellow, orange
On liquid media give a uniform turbidity
They grow on saline media (5-10% NaCl)
Milk-salt and yolk-salt agar are elective media for staphylococci

proteins with the formation of H2S, liquefy gelatin in the form of a funnel, for 4-5 days the funnel is filled with liquid

many extracellular substances that form staphylococci have antigenic properties.

fractions: hemolysin (destroys erythrocytes), leukocidin (destroys leukocytes), lethal toxin (kills rabbits), necrotoxin (causes skin necrosis in rabbit with intradermal administration), enterotoxin (causes food poisoning), exfoliatin (causes pemphigus in newborns - syndrome of "scalded skin")
Enzymes of aggression: hyaluronidase (destroys hyaluronic acid), plasmocoagulase (coagulates blood plasma), DNAse (destroys DNA), lecithovitellase (destroys lecithin), fibrinolysin (destroys fibrin clots)

W. E. Sause et al Antibody-Based Biologics and Their Promise to Combat Staphylococcus aureus Infections. Trends in Pharmacological Sciences. Volume 37, Issue 3, p231–241, March 2016

especially to diamond green, are often resistant to penicillin. form an enzyme penicillinase.

normal human microflora (carriers). Staphylococcus aureus colonizes the nasal passages, abdominal cavity, axillary regions. Epidermal staphylococcus occupies the smooth skin, the surface of the mucous membranes. Saprophytic staphylococcus occupies the skin of the genitals, the mucous membrane of the urinary tract.
Most infections are endogenous and the infection is associated with the transfer of the pathogen from the places of colonization to the traumatized (damaged) surface.

century, i.e. they are dangerous and very common, especially in maternity hospitals, in surgical departments.
1) source of infection - a sick person or a healthy carrier;
2) the transmission mechanism is mixed;
3) transmission ways: airborne, airborne, contact, food;
4) susceptibility of the population - susceptibility depends on the general condition and age; The most susceptible are newborns and infants.

fabric; Staphylococci penetrate through damaged skin, mucous membranes of the mouth, respiratory tract, genitourinary system, etc.
Staphylococci reproduce at the site of penetration, form exotoxin and enzymes of aggression and cause the formation of local purulent-inflammatory foci. Propagating from these foci of staphylococci can enter the blood (sepsis), and with blood - into other organs (septicopyemia).
The incubation period is from several hours to 3 to 5 days.

of diseases. They affect the skin (furuncles, carbuncles), subcutaneous fat (abscesses, phlegmon), respiratory tract (tonsillitis, pneumonia, sinusitis), cause mastitis, purulent myositis and muscle abscesses, brain abnormalities after traumatic brain injuries, endocarditis, affect bones osteomyelitis, arthritis), affect the liver, kidneys, urinary tract (pyelonephritis, cystitis). Especially dangerous are the diseases when staphylococci enter the blood (sepsis) and affect internal organs (septicemia). Staphylococcal infections are accompanied by intoxication, fever, headache.
Diseases are acute, but may also be chronic.

in newborns. The disease begins violently, characterized by the formation of large foci of erythema on the skin with the formation of large blisters (as in thermal burns) and the exposure of wet eroded areas.

1980 in women aged 15 to 25 years using tampons during menstruation. It is manifested by high fever (38.8° C and above), vomiting, diarrhea, rash, drop in blood pressure and development of shock, often leading to death.

to 6 hours after eating the infected foods, usually confectionery products with cream, canned food, meat and vegetable salads. Manifestations disappear or significantly weaken in 24 hours even without treatment.

to staphylococcal toxins, which leads to long, chronic illnesses.

a common cause of skin infection in children and are associated with many multidrug-resistant organisms

pyogenic microbes into the soft tissues of the palmar surface of the finger (as a rule, staphylococci, less often streptococci, sometimes a mixed pathogenic microflora is noted)

in the form of acute inflammation of the components of the lymphatic pharyngeal ring, most often the palatine tonsils caused by streptococci or staphylococci, less often by other microorganisms, viruses and fungi

blood, vomit, food
Bacterioscopic, bacteriological and biological methods are used
Serological reactions did not find application

and microscopy; in the smear are visible leukocytes, neutrophils, individual round cells of staphylococci and disordered clusters resembling a bunch of grapes (blood is not prepared from a blood smear)

material on nutrient media (more often on blood agar for detecting hemolysis) and then conducting its identification - study morphology (Gram stain), the presence of pathogenicity factors (plasmocoagulase, lecithovitelase) and biochemical properties (anaerobic cleavage of mannitol and glucose); the definition of an antibioticogram is mandatory; staphylococci are representatives of normal microflora, therefore, it is impossible to be limited by the isolation and identification of the pathogen, quantitative methods of analysis are needed-determination of the number of microbes in the sample

get vomiting and diarrhea in an hour and they die

to determine the antibioticogram
In recent years, patients have been isolated from staphylococci, resistant to most chemotherapeutic drugs. In such cases, antitoxic anti-staphylococcal plasma or immunoglobulin obtained from the blood of donors immunized with staphylococcal anatoxin is used for treatment
When chronic forms of diseases are also introduced staphylococcal anatoxin, use autovaccine.

can be used.
Nonspecific prevention is more important - it is compliance with sanitary and hygienic rules, tempering the body