Is Cryptococcus Neoformans Disease Hazardous

Parasitical Worms.com Cryptococcus neoformans micro-fungi group fungi, characterized by the presence of very thick mucopolysaccharide sachets, no staining of dyes, surrounding cells.
Healthy as well as immunocompromised individuals can be infected by inhaling fungal spores in the air, C.neoformans has a strong affinity for the central nervous system so encephalitis - meningitis is a clinical manifestation The most common disease is increasing according to the AIDS epidemic and the popularity of organ transplant treatment as well as the widespread use of corticosteroids.
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. Epidemiological characteristics
C.neoformans is the only species of the Cryptococcus genus capable of causing disease in humans. Although many cases of C albidus and Claurenti infections have been reported, the pathological roles of these two species have not been confirmed.
C.



.neoformans consists of four serotypes (serotypes) classified into two categories (serotypes): serotypes A and D of Var.neoformans, B and C of var. gattii. (However, based on differences in gene structure, many recent studies have tended to class A serotypes into a distinct category, var.grubii)
The geographic distribution, reservoir, biological characteristics and pathogenicity of Cneoformans vary depending on the thing. Var.neoformans are present throughout the world.
They are classified in the dried old feces of birds, especially pigeons, and in the soil contains many droppings, bats, chickens .



... Long-term towers - churches, lower floors of old buildings, sills Windows, straw storage - dry grass .. are places that attract birds and bats to live and become an important source of fungi.
However, it is seldom isolated from fresh, moist bird droppings because C.neoformans does not grow in an alkaline environment. Var.neoformans predominate on AIDS patients.



. While var.gattii is never found in bird droppings or in soil, there is a lot of decaying material that accumulates in the niches of the eucalyptus tree (Eucalyptus spp), so they are the host Weakness of C.neoformans infection in the tropics develops many of these trees damaged Africa, Australia, Asia and South America.
The ability to cause disease primarily in healthy people has shown that car.gattii is actually a pathogenic fungus, without the need for the host's weakened immune status, in other words, not an opportunistic agent. Therefore, the prevalence of var.gattii is declining in general cases of C.neoformans infection. In Vietnam var.



neoformans and var.gattii are isolated from clinical samples with the advantage of var.neoformans.
C.neoformans spores are spread by dust into the air, invade the human body through the respiratory tract and will be destroyed by alveolar macrophages, preventing the fungus from spreading into the blood.
As the body's resistance decreases, the fungus escapes into the bloodstream and attacks other organs, especially the central nervous system.
The host's immune response to C. neoformans largely depends on the T-lymphocyte immune function of the immune system Therefore, the causes of T-cell depletion are favorable for the development of the disease. .



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Previously, malignant blood diseases were the leading risk but now, it has become secondary to AIDS, long-term treatment with corticosteroids and organ transplants. In addition, diabetes, sarcoidosis, splenectomy, rheumatoid arthritis, lupus erythematosus, stork ... are also associated with C. neoformans infection
Although the important role of immunology for C pathology neoformans has been confirmed, a significant proportion, about 10% - 50% of the fungal encephalitis - meningitis in HIV group (-) has did not find any extradition factors related to host resistance.
2. SYMPTOMS
The stage of lung invasion is usually silent or transient. The majority of patients are diagnosed when there is manifestation of central nervous system damage.



. In AIDS patients, common skin lesions may occur before or concurrently with encephalitis - meningitis.
Primary lung form
The primary form of the lung often has a variety of processes that are difficult to predict especially on previously healthy bases.
The fungus can persist for many years in the bronchus with prolonged positive sputum cultures but does not cause pathological manifestations.
Some cases have pneumonia but the disease is usually self-limiting, requiring no treatment In 50% of these patients, the onset is gradual with symptoms of a dry cough, vague chest pain, fatigue, usually no fever or mild fever, night sweats.
The remaining half are detected on periodic chest X-ray with obvious nodular or mass pneumonia lesions.
Pleural effusion, umbilical lymph node enlargement, calcification or cavernization are rare. These infectious images will disappear after months. However a certain proportion will progress into chronic, some silently spread along the bloodstream to the central nervous system.
The clinical picture is usually more severe in AIDS patients, which can lead to acute respiratory failure.



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Meningitis
This is the most common and the most fatal form of C. neoformans infection . The majority of cases occur after the primary lung is not detected, only <30%.

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