Print version ISSN 0036-4665
Rev. Inst. Med. trop. S. Paulo vol.54 no.2 São Paulo Mar./Apr. 2012
Síndrome nefrótica associada à toxoplasmose. Relato de sete casos
Julio ToporovskiI; Simone RomanoI; Suzana HartmannI; Wanda BeniniI; Pedro Paulo ChieffiII, III
IPediatric Department, Medical School of Santa Casa, São Paulo, SP, Brazil
IIPathology Department, Medical School of Santa Casa, São Paulo, SP, Brazil
IIITropical Medicine Institute of São Paulo, São Paulo, SP, Brazil (LIM 06)
The concomitance of nephrotic syndrome and acute infection by Toxoplasma gondii is a rare occurrence in humans. In this paper seven cases of children, ranging from 11 months to 7 year-old, with concomitant nephrotic syndrome and asymptomatic acute T. gondii infection are reported. In one of those patients only the administration of anti-Toxoplasma therapy was enough to control the clinical and laboratory manifestations of the disease. In the other patients it was necessary to introduce corticosteroids or other immunosuppressant drugs. Three patients had complete clinical and laboratory improvement and the remaining showed only a partial response.
Keywords: Toxoplasma gondii; Nephrotic syndrome; Children.
Ocorrência concomitante de síndrome nefrótica e infecção aguda por Toxoplasma gondii em seres humanos é situação pouco frequente. No presente trabalho são relatados sete casos de crianças, com idade variável entre 11 meses e sete anos, que apresentavam síndrome nefrótica e infecção aguda por T. gondii assintomática. Em um dos pacientes o tratamento específico anti-Toxoplasma foi suficiente para controlar clínica e laboratorialmente as manifestações da doença. Nos demais foi preciso administrar corticosteróides ou outras drogas imunossupressoras. Após introdução desse esquema três pacientes apresentaram remissão completa dos sintomas; os demais apenas remissão parcial.
Nephrotic syndrome (NS) is mainly characterized by significant proteinuria, defined in children by values larger than either 40mg/m2/h or 50 mg/kg/day and serum albumin equal or less than 2.5g%. The whole picture includes edema, hypercholesterolemia, and urinary excretion of lipids. In childhood NS is primary or idiopathic in 80-90% of cases; however, NS may be secondary when due to systemic diseases like diabetes or cancer, immune or infectious disorders, besides drug use. Among the infectious causes, in this paper, the association with toxoplasmosis will be highlighted.
Toxoplasma gondii, protozoan agent of toxoplasmosis, belongs to the phylum Apicomplexa and family Sarcocystidae. Although capable of infecting many vertebrate species, both wild and domestic cats are its definitive hosts, also known as complete hosts, because they allow the parasite´s full development. Other susceptible hosts, including humans, are considered incomplete hosts, in which the Toxoplasma´s life cycle develops only partially.
Infection with T. gondii can assume serious aspects when it occurs either in the congenital form or in immunosuppressed patients10. In immunocompetent individuals, when transmission occurs after birth, toxoplasmosis commonly has asymptomatic or oligosymptomatic courses. Several forms of presentation are known, with development of variable clinical manifestations; however, renal involvement with glomerulonephritis or nephritic syndrome is a rare event in patients infected with T. gondii2,4,7,9,12,13,14,21.
Due to the high frequency of toxoplasmic infection it is mandatory in our department to perform anti-Toxoplasma antibody tests in all children with nephrotic syndrome. The aim of this study is to report the clinical, laboratorial, therapeutic, and evolutive aspects of children who had concomitant nephrotic syndrome and T. gondii infection.
A survey of medical records of outpatients who were diagnosed with nephrotic syndrome and, concomitantly, positivity for IgM antibodies to Toxoplasma, in the Pediatric Nephrology of Santa Casa de Misericórdia de São Paulo was conducted. In the period from 1999 to 2010 seven cases had been found; four were males and three females.
The initial clinical picture was the presence of edema and proteinuria. None of the patients showed specific symptoms for toxoplasmosis, such as fever or lymphadenopathy. The detection of IgM and IgG anti-Toxoplasma antibodies was performed by enzyme linked immunosorbent assay (ELISA). In six cases renal biopsies had been performed.
Almost all patients were submitted to the following biochemical tests: total cholesterol, serum urea and creatinine, and protein in urine of 24 hours. In only one patient, due to lack of sphincter control, proteinuria was assessed by the protein and creatinine ratio in a unique urine sample. Results of laboratory tests are shown in the Table 1.
All patients received initially anti-toxoplasmosis treatment: sulfadiazine (100 mg/kg/day), pyrimethamine (1 mg/kg/day) and folinic acid (10 mg/day), during at least one month, except those referred by other services, in which steroids had already been administered, receiving anti-Toxoplasma therapy associated to steroids.