#Histoplasmosis sketchy micro skin#

India ink preparation and cryptococcal antigen agglutination are commonly used diagnostic methods.I've been struggling with learning biochemistry this Christmas break.Cryptococcal meningitis is a common cause of death among HIV/AIDS patients The most common cause of fungal meningitis.Only pathogenic yeast known to have a polysaccharide capsule.Detection of Antibody: Serum antibodies can be detected by agglutination and immunofluorescence.Slide latex agglutination test has a sensitivity of 90% in the cases of cryptococcal meningitis. Latex agglutination test is most useful in the detection of cryptococcal polysaccharide antigen. Detection of Antigen:В Tests for capsular antigen can be performed on CSF and serum.Identification: Cryptococcus neoformans is identified by urease production and carbohydrate assimilation test, and confirmed by direct immunoflurorescence using a fluorescein-labeled anti- neoformans antibody. neoformans in Bird Seed Agar (source: The University of Adelaide) It is usually surrounded by a wide refractile capsule. Microscopy and stainingД¬ryptococcus neoformans appear as a spherical, single or multiple budding, thick-walled yeast that is 2-15 Ојm (wide variation in size) in diameter. Common specimens include spinal fluid (CSF), tissue, exudates, sputum, blood, and urine. Specimens: Specimens depends on clinical presentation and suspected disease conditions.

#Histoplasmosis sketchy micro skin#

Skin and other infections: Sometimes skin, lymph nodes, bones are involved.Reactivation of old healed lesions may occur. Lung infections: Pulmonary disease is increasing nowadays particularly in the immunocompromised hosts.Blurry vision (and other cranial nerve deficits).Change in mental status (ranging from confusionВ to lethargy to coma).Signs and symptoms ofВ cryptococcal meningitis.About 5-8% of patients with AIDS develop cryptococcal meningitis. All untreated cases of cryptococcal meningitis are ultimately fatal. Cryptococcal meningitis: Only in a small proportion of cases, hematogenous spread results in subacute or chronic meningitis or meningoencephalitis.People with immune-compromised status are likely to be affected more and have serious outcomes Infection occurs from the environment usually by inhalation, especially of dust containing excreta of pigeons but the infection is not transmitted from person to person. Cryptococcal infection occurs throughout the world sporadically. Important risk factors include AIDS, corticosteroid therapy, lymphoma, and T cell dysfunction. DiseasesД¬ryptococcosis is most often seen in immune-compromised patients with impaired T cell immunity. Phenoloxidase also protects the organism from oxidant released by phagocytic cells. It has been found that increased melanin production can decrease lymphocyte proliferation and tumor necrosis factor production. Melanin is might act as a virulence factor by making the organism resistant to leukocytes attack. Phenoloxidase: This enzyme is responsible for melanin production.Ideal size range for alveolar deposition: the cell size reduction, resulting from capsular collapse, places the yeast in the ideal size range for alveolar deposition.Protection under drying condition: The capsule collapses and protects the yeast.Anti-phagocytic: Polysaccharide capsule contains compounds that are not recognized by phagocytes.Capsule: Cryptococcus neoformans is the only pathogenic yeast known to have a polysaccharide capsule.Virulence Factors of Cryptococcus neformans The inflammatory reaction is usually minimal or granulomatous. Other common sites of dissemination include the skin, adrenals, bone, eye and prostate gland. In immune-compromised patients with impaired T cell immunity, the yeasts may multiply and disseminate to other parts of the body but preferentially to the central nervous system (neurotropic), causing cryptococcal meningitis. The primary pulmonary infection may be asymptomatic or may mimic influenza-like respiratory infection often resolving spontaneously. Infection is initiated by inhalation of the yeast cells. 2.3 Detection of Antigen and/or Antibody.1.1 Virulence Factors of Cryptococcus neformans.