Pathology Diagnosis and Treatment

P. marneffei is an emerging fungal pathogen whose clinical prevalence has paralleled that of the increasing incidence of patients with human immunodeficiency virus (HIV).

Penicilliosis due to P. marneffei in Southeast Asia is the third most common opportunistic infection, after tuberculosis and cryptococcosis, in HIV patients in northern Thailand, and it is considered an AIDS-defining illness in the region. P. marneffei infection is endemic in Southeast Asia, with a particular focus in Thailand, southern China, Hong Kong, Vietnam, northeastern India, and Taiwan (Vanittanakom et al., 2006). Penicilliosis due to P. marneffei has been also reported in HIV patients residing outside of the endemic areas. The majority of these cases correspond to patients with a history of travel to the Southeastern Asia. Infection by P. marneffei has also been noted in other groups of immunocompromised patients, such as those having Hodgkin's disease, tuberculosis, or autoimmune disease (Lupi et al., 2005).

Infection by P. marneffei is presumed to occur by inhalation of conidia produced by the asexual development programme at 25°C, as has been noted for other dimorphic fungal pathogens such as Histoplasma capsulatum where infection occurs by inhalation of airborne conidia (Maresca & Kobayashi, 1989) or Coccidioides immitis due to inhalation of arthroconidial cells (Stevens, 1995). Once in the alveolar cavities of the lungs, alveolar macrophages, the primary defence response, engulf the fungal conidia. In immunocompromised individuals, P. marneffei is capable of colonizing and killing the macrophages, and disseminating throughout the host. Systemic penicilliosis presents symptoms which include fever, anaemia, weight loss, and skin lesions, lymphadenopathy, splenomegaly, and hepatomegaly, and it is indistinguishable from other mycoses such as histoplasmosis (Mootsikapun & Srikulbutr, 2006). Consequently, laboratory identification is required for the correct diagnosis of penicilliosis due to P. marneffei. A number of diagnostic tests have been developed that include culture and staining methods (Lim et al., 2006; Supparatpinyo et al., 1992b; Supparatpinyo & Sirisanthana, 1994; Chaiwun et al., 2002), serological tests (Cao et al., 1998, 1999; Pornprasert et al., 2005) and molecular techniques using polymerase chain reaction (Lindsley et al., 2001; Tsunemi et al., 2003).

Penicilliosis due to P. marneffei is fatal if untreated. Infections usually respond to treatment with 0.6 mg/kg/day intravenous amphotericin B for 2 weeks and 400 mg/day oral itraconazole for 10 weeks (Sirisanthana et al., 1998). Relapses have been reported 6 months after cessation of therapy (Supparatpinyo et al., 1992a), so secondary prophylaxis with oral itraconazole is highly recommended (Supparatpinyo et al., 1998).

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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