What does Neisseria meningitidis look like?
meningitidis are grey and unpigmented on a BAP and appear round, smooth, moist, glistening, and convex, with a clearly defined edge. N. meningitidis appear as large, colorless-to-grey, opaque colonies on a CAP.
What is the structure of Neisseria meningitidis bacteria?
N. meningitidis is a Gram-negative diplococcus since it has an outer and inner membranes with a thin layer of peptidoglycan in between. It is 0.6–1.0 micrometers in size. It tests positive for the enzyme cytochrome c oxidase.
What kind of bacteria is Neisseria meningitidis?
Bacteria called Neisseria meningitidis cause meningococcal disease. About 1 in 10 people have these bacteria in the back of their nose and throat without being ill.
What is the description of meningitis?
Meningitis is an inflammation (swelling) of the protective membranes covering the brain and spinal cord. A bacterial or viral infection of the fluid surrounding the brain and spinal cord usually causes the swelling. However, injuries, cancer, certain drugs, and other types of infections also can cause meningitis.
Is Neisseria meningitidis acid-fast?
Neisseria meningitidis is a Gram-negative, non-spore forming, non-motile, encapsulated, and non-acid-fast diplococci, which appears in kidney bean shape under the microscope.
Is Neisseria meningitidis Cocci?
Meningococci (Neisseria meningitidis) are gram-negative cocci that cause meningitis and meningococcemia. Symptoms, usually severe, include headache, nausea, vomiting, photophobia, lethargy, rash, multiple organ failure, shock, and disseminated intravascular coagulation. Diagnosis is clinical, confirmed by culture.
What is the morphology of Neisseria?
Morphology: “Kidney bean” or “coffee bean” shaped cocci. Occurring singly, but more often in pairs with adjacent sides flattened. One species ( Neisseria elongata ) is an exception and consists of short rods 0.5 micrometers in width and is often arranged as diplobacilli or in short chains.
Is Neisseria meningitidis cocci?
Where Neisseria meningitidis is found?
N. meningitidis bacteria are found in the nose and throat without causing disease. Most people exposed to N. meningitidis do not become ill.
Where is Neisseria meningitidis most likely to be found?
Anyone can get meningococcal disease, but people who live or travel to certain areas of the world are more likely to get it. The “meningitis belt” of sub-Saharan Africa has the highest rates of meningococcal disease in the world.
What is the pathology of meningitis?
The pathogenesis and pathophysiology of bacterial meningitis involve a complex interplay between virulence factors of the pathogens and the host immune response [3,4]. Much of the damage from this infection is believed to result from cytokines released within the CSF as the host mounts an inflammatory response.
What is the main cause of meningitis?
Viral infections are the most common cause of meningitis, followed by bacterial infections and, rarely, fungal and parasitic infections.
What is the Gram stain and shape of Neisseria?
Neisseria gonorrhoeae, the causative agent of gonorrhoea, is a Gram negative, coffee-bean shaped facultative intracellular diplococcus bacterium, the classical sexually transmitted bacteria.
Is Neisseria aerobic or anaerobic?
aerobic
Abstract. The human pathogen Neisseria meningitidis is the major causative agent of bacterial meningitis. The organism is usually treated as a strict aerobe and is cultured under fully aerobic conditions in the laboratory.
Is bacterial meningitis Gram positive or negative?
Acute bacterial meningitis can be caused by different Gram-negative bacteria including meningococcal and H influenzae. This article covers Gram-negative meningitis caused by the following bacteria: Escherichia coli. Klebsiella pneumoniae.
Is Neisseria Gram-negative?
Neisseria species are Gram-negative cocci, 0.6 to 1.0 μm in diameter. The organisms are usually seen in pairs with the adjacent sides flattened. Pili, hairlike filamentous appendages extend several micrometers from the cell surface and have a role in adherence.
How do you describe morphology?
morphology, in biology, the study of the size, shape, and structure of animals, plants, and microorganisms and of the relationships of their constituent parts. The term refers to the general aspects of biological form and arrangement of the parts of a plant or an animal.
Is Neisseria a shape?
Neisseria spp. are a Gram-negative non-spore-forming diplococcus that has a flattened shape; its size ranges between 0.6–0.8 μm. They are oxidase-positive, non-acid-fast cocci or plump rods.
Where is meningitis most commonly found?
Meningococcal disease occurs worldwide, with the highest incidence of disease found in the ‘meningitis belt’ of sub-Saharan Africa. In this region, major epidemics occur every 5 to 12 years with attack rates reaching 1,000 cases per 100,000 population.
Where is Neisseria found?
upper respiratory tract
The Gram-negative bacteria genus Neisseria includes both pathogenic and commensal species that are found primarily in the upper respiratory tract of humans and animals.
Where does Neisseria grow?
Neisseria spp. grow best aerobically in an atmosphere containing 5–10% carbon dioxide at a temperature of 89.6–98.6°F (32–37°C) and a pH of 7–7.5. Cell size ranges from 0.6 to 1.5 mm depending upon the species source of the isolate and the age of the culture.
Where did Neisseria meningitidis come from?
Neisseria meningitidis (N. meningitidis) was first discovered in 1887 by Weichselbaum from analyzing the cerebrospinal fluid (CSF) of a patient infected with meningitis. [1] It is a human-specific bacterium that causes a multitude of illnesses, collectively termed meningococcal disease.
What are the characteristics of bacterial meningitis?
Early clinical features of bacterial meningitis are nonspecific and include fever, malaise and headache; and later on, meningismus (neck stiffness), photophobia, phonophobia and vomiting develop as signs of meningeal irritation [van de Beek et al. 2004].
Why is protein high in meningitis?
During bacterial infection, the protein level in the CSF goes up, due to the increased numbers of replicating bacteria and body cells fighting the infection, with both of them having a high concentration of protein. High levels of lactate in CSF indicate a higher likelihood of bacterial meningitis.
Who is generally at highest risk for meningitis Why?
Infants, teens and young adults, and older adults have the highest rates of meningococcal disease in the United States.