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               speciation does not influence therapy.  Treatment includes surgical debridement of involved
               areas where accessible and amphotericin B.[533]

                       PENICILLIOSIS.--  Infections with Penicillium marneffei are seen in HIV-infected
               persons living in Southeast Asia, the southern part of China, the Philippines, and Indonesia.
               Most infected persons will have a CD4 lymphocyte count below 100/µL.  Exposure to soils,
               particularly in the rainy season, appears to be a risk factor.  Infections tend to be disseminated.
               Clinical findings may include intermittent fever with or without chills, skin lesions, malaise,
               chronic productive cough, pulmonary infiltrates, anemia, hepatosplenomegaly, generalized
               lymphadenopathy, diarrhea, and weight loss.  About two-thirds of patients will have skin lesions
               that may be the first sign of infection. The lesions are most frequent on the face, upper trunk, and
               extremities. The lesions may occur as papules, a generalized papular rash, necrotic papules, or
               nodules.  Papules with central necrotic umbilication may resemble lesions of molluscum
               contagiosum.  The skin lesions may resemble those of disseminated mycobacterial or fungal
               diseases.[453,534,535]
                       Diagnosis can be made via culture of blood.  About half of patients will have a
               septicemia.  Culture of tissues from affected sites can be performed, with the best yield from
               bone marrow, skin scraping, or lymph node biopsy. At autopsy, the most common sites of
               involvement are lymph nodes, liver, lung, kidney, and bone marrow.[534,535,536]
                       P marneffei is found in the mycelial form in the environment, but it grows as a small
               spherical to oval 3 to 8 micron yeast form in tissues and appears very similar to, but slightly
               larger than, H capsulatum, and slightly smaller than P jiroveci (carinii) in size with the Gomori
               methenamine silver (GMS) and periodic acid-Schiff (PAS) stains.  Organisms are often abundant
               both intracellularly and extracellularly.  The yeast form of the organism may be found both
               intracellularly within macrophages, and also in the extracellular environment.  However, the
               small size of the organisms may cause confusion with cellular debris.  The yeast cells resemble
               the spores of H capsulatum but the distinctive central transverse septum is unique to P marneffei.
               In addition, H capsulatum undergoes division by budding while P marneffei uses a process of
               "fission" to generate a septum and produce daughter cells.  Toxoplasma tachyzoites do not bud or
               produce septae.[537]
                       Microscopically in immunocompetent hosts, there is typically a granulomatous reaction
               or a localized abscess.  However, in immunocompromised hosts the tissue reaction includes
               necrosis without granuloma formation, and the predominant cell present is a macrophage
               engorged with the yeasts.  Treatment may consist of itraconazole, ketoconazole, flucytosine, or
               amphotericin B.  Most patients respond to initial therapy, but the relapse rate approaches
               50%.[454,534,536]

                       SPOROTRICHOSIS.-- Infection with the dimorphic fungus Sporothrix schenckii, which
               has a worldwide distribution, is most commonly cutaneous from traumatic inoculation, with
               lesions that appear most often on the face, trunk, and extremities.  Exposure to cats, with biting
               and scratching, is a risk factor.  The lymphocutaneous form of the disease accounts for over 75%
               of all cases and is characterized by the emergence of a 2 to 4 cm indurated papule that develops
               about 7 to 30 days after inoculation of the fungus into the skin. Progressive induration leads to
               nodule formation with subsequent ulceration and crusting.  Additional nodules appear in the
               lymphatic drainage from the site of inoculation. The lesions may soften and produce cutaneous
               fistulae.  On microscopic examination, the lesions show granulomatous inflammation with
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