Effect of Toxoplasma co-inefected with intestinal helminthes on cell mediated immunity to tuberculosis patients.

The effect of intestinal helminthes (IH) and Toxoplasma gondii (Tox) co-infection on anti-mycobacterium tuberculosis (MTB) immunity in patients with active pulmonary tuberculosis was studied in 96 patients of 4 groups. Thirteen patients had TB+IH+Tox (G1), 15 had TB+IH (G2), 21 had TB+Tox (G3) and 47 had TB (G4). The mean diameter of tuberculin and toxoplasmin tests was measured to assess cell mediated immunity. Anti-Toxoplasma IgG1 & IgG4 antibodies were sought in toxoplasmic patients by ELISA for Thelper1 (Th1) and Th2 cytokine responses respectively. All patients were treated by 6 months anti-MTB therapy. Specific anti-IH therapies were given for patients with concomitant IH. Sputum examination for acid fast bacilli was done 2 weeks post-treatment and duration of sputum clearance was recorded. The results showed that IH co-infection had significant negative effect on mean diameter of tuberculin test compared to G4 (5.87 +/- 0.08 vs 8.65 +/- 0.05 mm; P < 0.01). Concurrent Tox with TB significantly increased tuberculin test mean diameter (10.89 +/- 0.11 vs 8.65 +/- 0.05 mm; P < 0.05). Mean level of anti-Tox IgG1 among G3 was significantly higher than in G1 (0.88 +/- 0.05 vs 0.55 +/- 0.02; P < 0.001), but vice versa was with IgG4. Mean tuberculin diameter increased significantly post-treatment in all Gs except G3. Anti-Tox IgGC1 showed significant increase (0.55 +/- 0.02 to 0.82 +/- 0.03; P < 0.001) but IgG4 showed significant decrease (0.62 +/- 0.07 to 0.45 +/- 0.06, P < 0.01) post-treatment in G1, but G3 was insignificantly affected. The duration of sputum clearance was significantly longer in patients with IH co-infection compared to G4 (29 +/- 1 vs 21.8 +/- 4.6 days; P < 0.001).

Bancroftian filariasis: clinical parasitologic and serologic evaluation after 4 years applying two antifilarial regimens.

In August 1 997, 124 individuals out ot 1,110 were selected as being seropositive for circulating filarial antigen OG4C3 (CFA). Ten healthy children proven negative for CFA were used as controls. The patients were classified into: G1 28 patients; 20 asymptomatic microfilaraemic and 8 symptomatic amicrofilaraemic (AMF), G2 80 patients, 22 asymptomatic MF, 48 asymptomatic AMF and 10 symptomatic AMF and G3 16 asymptomatic AMF. G1 was treated by single annual dose of diethyl carbamazine (DEC) (6mg/kg), G2 by single annual dose of albendazole 400 mg and DEC 6mg/kg and G3 untreated. Four years later (2001), patients Were re-evaluated. Microfilaraemia prevalence in MF patients was lowered to 20% (G1) and 9.1% (G2). Antigenaemia prevalence was lowered to 46.4%, 17.5% and 87.5% in the three groups respectively. The disease became manifested among the asymptomatic in 5% (G1) and 10% (G2), but 25% (G3). The four years lowered the prevalence of microfilaraemia, but it was not sufficient for its elimination from the blood. So, a program to eliminate filariasis should be extended beyond this period to achieve no transmission and minimizes newly cases.