In Brazil, there have been no previous studies of Toxoplasma gondii infection in sickle cell anemia patients and carriers of severe forms of beta-thalassemia. This study evaluated T. gondii infection in patients with beta-hemoglobinopathies. A total of 158 samples, 77 (48.7%) men and 81 (51.3%) women, were evaluated. Three groups were formed: G1 (85 patients with sickle cell disease); G2 (11 patients with homozygous beta-thalassemia; G3 (62 patients with heterozygous beta-thalassemia). ELISA was employed to identify anti-T. gondii IgM and IgG antibodies, and molecular analysis was performed to determine beta-hemoglobin mutations. Fisher’s exact test was used to compare frequencies of anti-T. gondii IgM and IgG antibodies in respect to gender and age. Anti-T. gondii IgG antibodies were found in 43.5% of individuals in G1, 18.1% in G2 and 50% in G3. All samples from G1 and G2 were seronegative for anti-T. gondii IgM antibodies, but 3.2% from G3 were seropositive. Considering anti-T. gondii IgG antibodies, no statistical significant differences were found between these groups nor in seroprevalence between genders within each group. Despite this, comparisons of the mean ages between G1, G2 and G3 were statistically significant (G2 vs. G1: p value = 0.0001; G3 vs. G1: p-value <0.0001; G3 vs. G2: p-value = 0.0001). A comparison by age of patients with sickle cell anemia showed a trend of lower risk of infection among younger individuals. Therefore, this study demonstrates that T. gondii infection occurs in patients with beta-thalassemia and sickle cell anemia in Brazil as seen by the presence of anti-T. gondii IgM and IgG antibodies.

Patients carrying Chagasic megaesophagus (CME) are at high risk for esophageal carcinoma. We aimed to investigate mutations in the TP53 in patients carrying CME. Blood samples from 114 patients with Chagas disease (CD) were used. The samples were subjected to PCR-SSCP analysis and DNA sequencing in exons 5 and 7 of the TP53 gene. We observed mutations in the exon 5 codon 184 (GAT > AAT) in 14.8% of G1 (11/74), 10% of G2 (4/40), and 5% of G3 (2/40). We also observed the codon 185 mutation (AGC > AGG) in 14.8% of G1 (11/74), 10% of G2 (4/40), and 7.5% of G3 (3/40). Regarding Exon 7, a mutation (G > T) was observed in the intronic region in 2.7% of G1 (2/74), 7.5% of G2 (3/40), and none of G3 (0/40). Our study showed, for the first time, simultaneous mutations at codons 184 and 185 of the TP53 gene in patients with CME and Chagasic patients without megaesophagus. More studies are needed to assess whether the simultaneous presence of mutations at codons 184 and 185 increases the risk of developing esophageal carcinoma in these patients.