Be aware of infections due to A. schaalii, it is a uropathogen with potential invasiveness leading to severe infections. Taxonomy
Family: Actinomycetaceae,
Genus: Actinotignum schaalii
Formerly: Actinobaculum schaalii

Genus: Actinotignum
A. schaalii
A. urinale

Natural habitats
The natural habitat of A. schaalii remains unknown, but it is probably part of the commensal flora of the human genital or urinary tract.

Clinical significance
They are associated with genital and urinary tract infections, mainly in elderly and patients with underlying urological conditions.

Some evidence suggests that this bacterium may also cause urinary tract infections among pediatric patients.

Investigation must be performed for patients for whom urine culture remains ‘sterile’ under aerobic conditions whereas many Gram-positive rods and leukocytes appear on smear microscopy and of patients who do not respond to treatments for UTIs.

Severe infections have also been described, such as urosepsis, bacteremia, cellulitis and endocarditis.

Bacteremia with A. schaalii is associated with a mortality rate of 16%, with over 50% of patients experiencing severe sepsis.

Lactobacillus species produce lactic acid as their single or major metabolic end product from glucose fermentation

Taxonomy
Family: Lactobacillaceae
Genus: Ligilactobacillus murinus
Formely: Lactobacillus murinus

Natural habitats
They are widely distributed in the environment
They belong to the normal flora of the intestine, urogenital tract and mouth.

Clinical significance
Despite the reputation of lactobacilli as beneficial organisms, they can be involved in serious infections, especially in immunocompromised individuals.

Lactobacilli are particularly associated with advanced dental caries, where they are considered a secondary colonizer because of their preference for low-pH habitats, but probaply play a role in exacerbating existing lesions.

The clinical infections most commonly caused by lactobacilli are bacteremia and endocarditis, with an associated relatively high mortality rate, with the mouth, the primary route of entry to the bloodstream.

Lactobacillus species produce lactic acid as their single or major metabolic end product from glucose fermentation

Taxonomy
Family: Lactobacillaceae
Genus: Ligilactobacillus salivarius
Formely: Lactobacillus salivarius

Natural habitats
They are widely distributed in the environment
They belong to the normal flora of the intestine, urogenital tract and mouth.

Clinical significance
Despite the reputation of lactobacilli as beneficial organisms, they can be involved in serious infections, especially in immunocompromised individuals.

Lactobacilli are particularly associated with advanced dental caries, where they are considered a secondary colonizer because of their preference for low-pH habitats, but probaply play a role in exacerbating existing lesions.

The clinical infections most commonly caused by lactobacilli are bacteremia and endocarditis, with an associated relatively high mortality rate, with the mouth, the primary route of entry to the bloodstream.

Lactobacillus species produce lactic acid as their single or major metabolic end product from glucose fermentation

Taxonomy
Family: Lactobacillaceae
Genus: Lactocaseibacillus rhamnosum
Formely: Lactobacillus rhamnosum

Natural habitats
They are widely distributed in the environment
They belong to the normal flora of the intestine, urogenital tract and mouth.

Clinical significance
Despite the reputation of lactobacilli as beneficial organisms, they can be involved in serious infections, especially in immunocompromised individuals.

Lactobacilli are particularly associated with advanced dental caries, where they are considered a secondary colonizer because of their preference for low-pH habitats, but probaply play a role in exacerbating existing lesions.

The clinical infections most commonly caused by lactobacilli are bacteremia and endocarditis, with an associated relatively high mortality rate, with the mouth, the primary route of entry to the bloodstream.

Lactobacillus species produce lactic acid as their single or major metabolic end product from glucose fermentation

Taxonomy
Family: Lactobacillaceae

Natural habitats
They are widely distributed in the environment
They belong to the normal flora of the intestine, urogenital tract and mouth.

Clinical significance
Despite the reputation of lactobacilli as beneficial organisms, they can be involved in serious infections, especially in immunocompromised individuals.

Lactobacilli are particularly associated with advanced dental caries, where they are considered a secondary colonizer because of their preference for low-pH habitats, but probaply play a role in exacerbating existing lesions.

The clinical infections most commonly caused by lactobacilli are bacteremia and endocarditis, with an associated relatively high mortality rate, with the mouth, the primary route of entry to the bloodstream.

Lactobacillus species produce lactic acid as their single or major metabolic end product from glucose fermentation

Taxonomy
Family: Lactobacillaceae

Natural habitats
They are widely distributed in the environment
They belong to the normal flora of the intestine, urogenital tract and mouth.

Clinical significance
Despite the reputation of lactobacilli as beneficial organisms, they can be involved in serious infections, especially in immunocompromised individuals.

Lactobacilli are particularly associated with advanced dental caries, where they are considered a secondary colonizer because of their preference for low-pH habitats, but probaply play a role in exacerbating existing lesions.

The clinical infections most commonly caused by lactobacilli are bacteremia and endocarditis, with an associated relatively high mortality rate, with the mouth, the primary route of entry to the bloodstream.

Taxonomy
Family: Listeriaceae

Of the seven species within the genus Listeria, only L. monocytogenes and L. ivanovii are pathogenic.

Natural habitats
They are widely distributed in the environment

Clinical significance
Listeria ivanovii is primarily a pathogen of ruminants.

Systemic infections in immunodeficiency virus-infected and non-immunosuppressed patients have, however been described.

Is the bacterium that causes the infection listeriosis

It can grow and reproduce in the host’s cells and is one of the most virulent food-borne pathogens.

Taxonomy
Family: Listeriaceae

Of the seven species within the genus Listeria, only L. monocytogenes and L. ivanovii are pathogenic.

Natural habitats
They are widely distributed in the environment
They have been isolated from soil, decaying vegetables, sewage, water, animal feed, fresh and frozen poultry, raw milk, cheese and slaughter house waste.

Because of its widespread occurrence, L. monocytogenes has many opportunities to enter food productions and processing environments and, because of its ability to grow at 4oC, to cause human disease in persons ingesting colonized food.

Clinical significance
They cause the disease listeriosis, a serious infection caused by eating food contaminated with the bacteria.

The disease affects primarily pregnant women, the bacteria is able to cross the placenta, and infect the fetus, which may result in spontaneous abortion or stillbirth, newborns, and adults with weakened immune systems

Listeriosis is a serious disease for humans.
The two main clinical manifestations are sepsis and meningitis.

Meningitis is often complicated by encephalitis, a pathology that is unusual for bacterial infections

General information
The genus name Trueperella has been proposed in honor of the German microbiologist Hans Georg Trüper.

Taxonomy
Family: Actinomycetaceae
Genus: Treuperella pyogenes
Formely: Actinomyces pyogenes, Arcanobacterium pyogenes

Natural habitats
They are not part of the normal flora of humans, but they are part of the normal flora of animals and also cause infections there

Clinical significance
T. pyogenes may cause pyogenische infections in animals.

Flies for the transmission are suspected to be vectors.

Infections in humans occurs mainly in rural areas; wounds

Cause of; acute pharyngitis, urethritis, cutane- or subcutaneous abscesses or septic arthritis in a diabetic.