Development of membrane-based tests for the detection of urinary antigens and antibodies in human toxoplasmosis: preliminary studies in Ghanaian patients.
Two membrane-based ELISA systems were used in detecting Toxoplasma antigens and anti-Toxoplasma antibodies in urine samples collected from 54 ophthalmology (22 suggestive active and 32 suggestive past infection) patients and 26 pregnant women attending obstetrics/gynaecology clinic (OGP), suspected of toxoplasmosis by eye examination, past medical records and questionnaire, respectively, in Ghana from mid-February to April 2002. The antigen detecting ELISA was able to demonstrate antigen in 100% (22/22) ophthalmology (active infection) and 62.5% (20/32) ophthalmology (past infection) patients, and 42% (11/26) of OGP which included 3 that were sero-negative prior to and during this study, giving an overall prevalence of 66.3% (53/80). The urinary antigen positive samples also included 6 that were negative for both the Dye Test (DT) and latex agglutination test (LAT). Antigen was not detected in the urine of 22 normal (sero-negative for antibodies to Toxoplasma) individuals. The membrane-based urinary antibody detecting sandwich ELISA also detected anti-Toxoplasma antibodies in 100% (22/22) of ophthalmology (active infection) and 81.3% (26/32) of ophthalmology (past infection) patients, a total of 89% (48/54); and 80.8% (21/26) of OGP with an overall prevalence of 86.3% (69/80), including 7 ophthalmology patients' samples that were sero-negative for both DT and LAT. Antibody sero-positivity of the samples was determined by DT as 87% (47/54) in ophthalmology patients and 73.1% (19/26) in pregnant women, LAT as 85.2% (46/54) and 65.4% (17/26), and an overall prevalence as 82.5% (66/80) and 78.8% (63/80), respectively. The membrane-based ELISA systems appear promising but need to be investigated further for its efficacy as reliable diagnostic tests.
Ayi
Irene
I
Section of Environmental Parasitology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan. Ireneayi@hotmail.com
Akao
Nobuaki
N
Bosompem
Kwabena Mante
KM
Akafo
Stephen K
SK
Clarke
James
J
Nyador
Lydia
L
Apea-Kubi
Kwesi-A
KA
Fujita
Koichiro
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000913:Antibodies, Protozoan / Q000652:urine*; D000953:Antigens, Protozoan / Q000652:urine*; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005128:Eye Diseases / Q000469:parasitology* / Q000652:urine; D005260:Female; D005869:Ghana / Q000453:epidemiology; D006801:Humans; D007841:Latex Fixation Tests; D008297:Male; D051379:Mice; D008875:Middle Aged; D011145:Polyvinyls; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000469:parasitology / Q000652:urine*; D014122:Toxoplasma / Q000276:immunology / Q000302:isolation & purification*; D014123:Toxoplasmosis / Q000469:parasitology / Q000652:urine*; D005465:Fluorocarbon Polymers
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D011145:Polyvinyls; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers