SUMMARY OF THESIS^*

ASSIS, C. M. de – Estudo morfofisiológico de amostras de Paracoccidioides. São Paulo, 1997. (Tese de Doutoramento – Instituto de Ciências Biomédicas da Universidade de São Paulo.)

We report here the morpho-physiological characterization of 20 isolates of Paracoccidioides, isolated from patients with paracoccidioidomycosis and other sources such as penguin (Pygocelis adeliae) stools, visceras from na armadillo (Dasipus novencinctus, and from soil in different periods of time and from different regions from Latin America.

The results indicate the presence of some differences among the isolates, particularly with respect to the morphogenic and antigenic studies.

We analysed the growth in different culture media of the isolates at the temperature of 27° C. We also analysed the morphologic diversity by cultivating these isolates at constant and different temperatures.

We verified that the isolates of P. cerebriformis were temperature sensitive, when analysed their growth at temperature above 27° C. They presented neither morphology nor antigenic structure comparable to those reported to P. brasiliensis. We observed that the P. tenuis isolate consistently soften colonies, easily detachables from the culture medium, and whose micromorphologic structure were more tenuous than those of P. brasiliensis and P. cerebriformis. The isolates from P. cerebriformis displayed different pigments (white, ivory, yellow, pink, and gray), although their behaviour was not stable. In the other hand, pigments from P. brasiliensis and P. tenuis varied from white, ivory and brownish.

In this study we were not able to define a biochemical marker for the differentiation of the isolates. They all showed the same profile when proteinase, urease, phospholipase, chondroitinase, hyaluronidase, behaviour in canavanine-glycine-bromothymol blue and tetrazolium chloride, were evaluated. Additionally, the same biotype was found for all isolates when the Odds & Abbott system was used. However, small differences were found among the isolates: variation in the PZ, color intensity of the colonies, and time for development of the biochemical reactions.

The antigens of the isolates of P. brasiliensis and P. tenuis reacted against a pool of sera from patients with paracoccidioidomycosis and a purified human IgG anti-Pb, as well as against anti-Pb and anti-gp 43 kDa from Pb hyperimmune sera; the same, however, was not observed with the antigens of isolates of P. cerebriformis. We also verified lack of reactivity of the antigens of all isolates against anti-A. fumigatus, anti-H. capsulatum and anti-C. albicans hyperimmune sera. We detected the glycoprotein of 43 kDa, the immunodominant antigen of paracoccidioidomycosis, in the antigenic fractions of P. brasiliensis and P. tenuis.

The study of the components of the external surface of the cell wall of P. brasiliensis 9 isolate, soluble in NaCl 0.85%, demonstrated that its antigenic structure was very complex. We verified that the more intense bands were those corresponding to the proteic bands of 43, 54, and 78 kDa, present in extracts obtained at 5^th, 10^th, 15^th and 20^th days of culture of the fungus at 36° C. They were considered, therefore, the major antigens of the fungus. We observed in the crude antigenic extract obtained at the 10^th day of culture the higher number of proteic antigens, with the bands showing stronger intensity and higher protein concentration.

AMATO, VALDIR SABBAGA – Utilização do isotionato de pentamidina para o tratamento da leishmaniose mucosa. São Paulo, 1997. (Dissertação de Mestrado – Faculdade de Medicina da Universidade de São Paulo.)

American Tegumental Leishmaniasis (ATL) is an endemic disease of high morbidity in Brazil and, when caused by Leishmania (V) braziliensis, it may involve the mucosae, including the larynx and trachea, provoking respiratory failure and death. According to the World Health Organization, pentavalent antimonials are the drugs of choice for the treatment of ATL, but the treatment failure and a high rate of recurrence occur in the mucosal form treated with these medications. Pentamidine is considered to be the second-choice drug, although few papers are available in the literature about the assessment of this treatment. In the present study we treated 17 patients with mucosal leishmaniasis (ML) diagnosed by the Montenegro skin test, by serology using the indirect immunofluorescence reaction (IIRF), anatomopathological examination, and immunohistochemistry of a lesion biopsy. Pentamidine was used at the dose of 4 mg/kg on alternate days. Otorhinolaryngologic evaluation was performed weekly to determine activity of the lesion, and treatment was discontinued when healing of the lesions(s) occurred. At the end of treatment and at 3-month intervals for an undetermined period of time, clinical and otorhinolaryngologic evaluation was performed, as well as measurement of fasting glycemia, serum urea and creatinine, and a serologic test for leishmaniasis. Six patients (35.2%) reported previous treatment, one did not remember which drug he had been using, one took 200 mg/day ketoconazole for one year, and three took glucantime. Of these three patients, one developed intense myalgia after the use of 6 ampoules, a fact that motived treatment interruption, another received 2 ampoules/day for 30 days with no improvement, and another could not remember the dose received. Finally one patient took glucantime (2 ampoules/day for 15 days) and completed three cycles separated by 15-days intervals without a resolution of the clinical picture. This patient later took a cumulative dose of 1800 mg amphotericin B, again without healing of the lesion. The Montenegro skin test was positive in all patients. Histopathological examination showed nonspecific inflammatory lesions in 16 patients (94.1%) and amastigote leishmania forms were observed in only one patient. Immunohistochemistry carried out on 16 patients was positive in 12 (70.5%). Before treatment, all 17 patients had presented a positive IIRF. After treatment, follow-up of IIRF presented the following results: unchanged titers in eight patients (47.0%) with a mean follow-up of 13,5 months (range: 3 to 37 months), reduced titers in 3 (17.6%) with a mean follow-up of 14,6 months (range: 6 to 24 months), and negativity in 6 (35.6%) with a follow-up of 11,6 months (range: 7 to 23 months). Treatment with pentamidine isothionate led to healing of the lesions in 16 patients (94.1%). The mean dose needed to obtain healing of the lesions was 2872 mg, ranging from 2025 to 4320 mg. Mean follow-up time was 13.3 months (range: 3 to 37 months). One patient (6.25%) presented a recurrence four months after the end of treatment. With respect to tolerance of the medication, seven patients had no symptoms (41.1%). However, 10 patients (58.8%) presented the following disorders: increased urea and creatinine levels in 8 (47.0%) and leucopenia in one (5.8%), wich regressed with spacing of the pentamidine dose, with no need to interrupt treatment. One woman developed diabetes mellitus and was first treated with insulin, later glibenclamide and finally only by the appropriate diet. The patient currently shows normal fasting glycemia and glycosylated hemoglobin. Pentamidine isothionate is effective for the treatment and healing of ML lesions and was efficient in cases in wich treatment with antimonials, amphotericin B and ketoconazole failed. Only in one case was it necessary to discontinue treatment due to the side effects. For some of the patients there was no correlation between serology titers by IIRF and healing of the lesions.

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This thesis is available at the Library of the Instituto de Medicina Tropical de São Paulo.

Publication Dates

• Publication in this collection
  04 Feb 1999
• Date of issue
  Sept 1997