So. Angel et al., SCREENING FOR ACTIVE TOXOPLASMOSIS IN PATIENTS BY DNA HYBRIDIZATION WITH THE ABGTG7 PROBE IN BLOOD-SAMPLES, Journal of clinical microbiology, 35(3), 1997, pp. 591-595
We report the potential use of a specific Toxoplasma gondii DNA probe
(ABGTg7). We applied a dot blot hybridization assay to blood samples f
or the diagnosis of cerebral toxoplasmosis (CT), acute toxoplasmic lym
phadenopathy (ATL), and disseminated toxoplasmosis in transplant recip
ients (TRs). We studied a total of 84 individuals: 38 patients and 46
controls, We found positive hybridization signals for 12 (66.7%) of 18
patients with confirmed CT, 9 (52.9%) of 17 patients with ATL, and 2
(66.7%) of 3 TRs. PCR assays were performed in parallel for patients w
ith ATL, resulting in T. gondii DNA detection for 10 patients (58.8%).
A comparative study between dot blot and PCR assays performed with th
e blood of mice that had been experimentally infected with tachyzoites
gave similar results: 60 and 70% positive results, respectively. Fina
lly, the sum of positive values obtained by both DNA tests (dot blot a
ssay plus PCR) increased the rate of positivity for ATL patients to 76
.4%. These results demonstrate that the T. gondii ABGTg7 repetitive DN
A element is an additional useful resource for diagnosing Toxoplasma p
arasitemia in patients with CT and ATL and in TRs. Thus, our ABGTg7-ba
sed dot blot test may lead to an improvement in T. gondii detection me
thods in patients with acute toxoplasmosis.