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Memórias do Instituto Oswaldo Cruz
Fundação Oswaldo Cruz, Fiocruz
ISSN: 1678-8060 EISSN: 1678-8060
Vol. 91, Num. 5, 1996, pp. 637
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Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 91(5),
637. Sep/Oct 1996,
Research note
BCG and Praziquantel for Schistosomiasis Treatment
Luciana de Gouvea Viana^+ , Yerkes Pereira e Silva, Maria
Mnica de Aguiar Garcia, Marcia Nogueira Amorim, Naftale Katz,
Ana Lucia Teles Rabello
Laboratorio de Esquistossomose, Centro de Pesquisas Rene
Rachou-FIOCRUZ, Av. Augusto de Lima 1715, 30190-002 Belo
Horizonte, MG, Brasil
^+Corresponding author. Fax: 55-31-295.3115
Received 2 January 1996
Accepted 11 March 1996
Code Number: OC96114
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[TABLES AND FIGURES AT END OF TEXT]
Key words: Schistosoma mansoni - BCG -
praziquantel
Prior study has suggested that praziquantel could be used in
lower doses, one-third than the conventional, when associated
to BCG in non reactors patients to PPD (N Nohmi et al. 1993,
IV International Symposium on Schistosomiasis, p. 165). In
schistosomiasis, a higher degree of protective immunity was
obtained when BCG was used in combination with a non-living
vaccine of schistosomula (SL James et al. 1988 J Immunol
140: 2753) or paramyosin (TP Flanigan et al. 1989 J
Clin Invest 83: 1010). Mices immunized with F-T
schistosomula (frozen-thawed schistosomula) and BCG presented
a high degree of protection against cercariae challenge and
their peritoneal macrophages showed augmented schistoso-
mulicidal activity and increased TNF-a and IL-2 production (Y
Keisari et al. 1993 Immunobiol 188: 446-459). In the
present study, we investigated the interference of the
immunogenicity of BCG in the therapeutical efficacy of
praziquantel in patients infected with Schistosoma
mansoni.
A population of 41 S. mansoni infected students from
Sabara, in the State of Minas Gerais, Brazil, was selected by
Kato-Katz stool examination (N Katz et al. 1972 Rev Inst
Med Trop S o Paulo 14: 337-340). They comprised students
of both sexes (52.4% of males, 47.6% of females), from 12 to
22 years old (age mean: 15.12 +/- 2.43), with the intestinal
form of the parasitosis and having 12 to 2232 eggs of S.
mansoni per gram of feces (epg output mean: 374.16 per
gram of feces). All students were tested with five UT of
tuberculin purified protein derivated (PPD - Fundac o Ataulpho
de Paiva, S o Paulo, Brasil) and after 72 hr they returned for
test reading. Students were considered reactor if presented an
induration larger than or equal to five mm. Patients were
paired by age, sex and eggs of S. mansoni per gram of
feces, and divided in three groups: (1) 14 PPD non reactor
patients, vaccinated with one dose of intradermic BCG
(Fundac o Ataulpho de Paiva, S o Paulo, Brasil) and treated
with 20mg/kg of body weight of praziquantel 15 days after; (2)
15 PPD non reactor patients, non vaccinated and treated with
praziquantel 20 mg/kg of body weight; (3) 12 PPD non reactor
patients, treated with 60 mg/kg of body weight of
praziquantel. The volunteers were submitted to the study after
signed consent form from their parents in which the project
and the procedures were described. Four months after BCG
vaccination the Mantoux test was repeated and all children
became PPD reactors.
Drugs were administered under supervision. The assessment of
therapeutic efficacy was based on three consecutive daily
stool examinations, two slides from each sample of feces,
applying the Kato-Katz quantitative technique six months after
treatment. Patients were considered cured when no S.
mansoni eggs were detected in serial stool
examinations.
Statistical analysis was performed using Epi Info 5.0 software
(USD, Inc., Stone Mountain, Georgia). Anova or Kruskal-Wallis
analysis were applied depending on Bartlett's test for
homogeneity of variance.
It was observed a cure rate of 33.3% (4/12) in group (1) and
58.3% (7/12) in group (2). In group (3), the cure rate was
90.0% (9/10). No statistical significant difference has been
observed between groups (1) and (2) (p=0.90), but the cure
achieved in group (3) was statistically different from that
observed for groups treated with 20 mg/kg of body weight
(p=0.01).
In conclusion, BCG vaccination did not increase drug
efficiency of low dose therapeutical scheme of praziquantel in
schistosomiasis mansoni human infection.
Acknowledgments: to Mr Wilson Dias for his assistance
in the "Gabriela Leite Araujo" School. To the Municipal Health
Secretary of Belo Horizonte and MERCK^R for supplying PPD and
praziquantel, respectively.
Copyright 1996 Fundacao Oswaldo Cruz
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