[Antibodies against Toxoplasma gondii in patients with HIV in Yucatan]. / Anticuerpos contra Toxoplasma gondii en pacientes con VIH en Yucatán.

OBJECTIVE: To determine the prevalence of antibodies type IgG to T. gondii in patients with HIV infection type 1 in the Yucatan peninsula. METHODS: 95 patients with HIV and 100 blood donors as controls were studied. The search for IgG antibodies to T. gondii was done with a third generation solid-phase enzyme immunoassay. Clinical and demographic data were obtained. RESULTS: The prevalence of antibodies was higher (p = 0.003) in controls (69%, CI95 = 59-78%) than in patients (47%, CI = 36-57%). No relation was found between seroreactivity and the variables evaluated (gender, urban or rural home, age) nor with CD4 T-cell counts and clinical categories. CONCLUSIONS: The high prevalence of T. gondii antibodies in both groups suggests that the zoonosis is endemic in the Yucatan peninsula. This justifies the routine determination of antibodies and the use of therapeutic protocols for preventing encephalitis by toxoplasma in HIV patients as a high percentage of them would be at risk of developing it.

[Natural history of paroxysmal nocturnal hemoglobinuria in adolescents,adults, and children: the Mexican experience]. / Historia natural de la hemoglobinuria paroxística nocturna en adolescentes, adultos y en la edad pediátrica: la experiencia mexicana.

PURPOSE: To compare the clinical patterns and survival of young and adult (AP) versus paediatric (PP) patients with paroxysmal nocturnal haemoglobinuria (PNH). PATIENTS AND METHODS: The clinical records of 117 patients (82% AP, 18% PP) seen in four cities of the Mexican Republic were analysed, the clinical course and survival of both groups being compared. RESULTS: No sex difference was found in the two patient-groups: 51% and 52% males, 49% and 48% females in AP and PP, respectively. The onset of PNH had similar distribution for the two groups of patients: aplastic form, 45% in AP and 62% in PP; cytopenias, 24% in AP versus 27% in PP; haemolysis, 28% in AP and 9% in PP, and thrombosis, 3% in AP versus 0% in PP. The clinical features with significant difference were: anaemic+haemorrhagic syndrome (39 AP (40%) vs 14 PP (67%), p = 0.02), initial diagnosis of immunologic thrombocytopenic purpura (7 AP (7%) vs 7 PP (33%), p = 0.003), and death rate (17 AP (18%) vs 8 PP (38%), p = 0.04). The actuarial survival curves showed significant differences between both groups (p = 0.045, Cox-Mantel), with estimated 10-year survival of 81% for AP and 55% for PP, and 15-year survivals of 64% for AP and 55% for PP. CONCLUSIONS: Seemingly, PNH in paediatric age has poorer prognosis than in adults, which is associated to higher incidence of fatal haemorrhages due to thrombocytopenia.

[Infection with HTLV virus type I-II in patients with cervico-uterine cancer in the Yucatan peninsula, Mexico]. / Infección por virus linfotrópico de células T humanas tipo I/II en pacientes con cáncer cervicouterino de la península de Yucatán, México.

Southwestern Japan is an endemic zone with high prevalence of HTLV-I infection. In addition, a relation between cancer of the cervix and this retrovirus has been described. A recent study has demonstrated a low prevalence of HTLV-I/II infection in Yucatan, Mexico. However, cancer of the cervix is the most frequent oncological disease in this region. The objective of this study was to determine the relationship between cancer of the cervix and the HTLV-I/II infection. Sera from 123 patients with cancer of the cervix and 662 healthy women were screened for antibodies against HTLV-I/II by ELISA and agglutination test (PA). Results were confirmed by Western blot (WB). In the confirmed cases the differentiation between HTLV-I and HTLV-II was made by synthetic peptides. Only one woman (0.8%) had positive results in the patients group and two women (0.3%) had reactivity in the control group. In all these cases the antibodies were positive for HTLV-II. The prevalence in the group of patients with cancer of the cervix was similar to that of the control group. We therefore concluded that in Yucatan, Mexico there is no relation between HTLV-I/II infection and cancer of the cervix.

Low prevalence of HTLV-II in Mayan Indians in the Yucatan Peninsula, Mexico.

Infection with HTLV-II is endemic in Amerindians, with prevalence ranging from 0.89% - 33%. To determine the prevalence of HTLV-II among indigenous Mayans in the Yucatan Peninsula of Mexico, 440 indigenous Mayans were recruited, all native to and residents of one of six Mayan communities in the Yucatan Peninsula, (Xohuayan n=144, Yaxachen n=101, Kanxoc n=84, Xocen n=40, Nabalan n=46 and X'calot n=25) between May, 1992 and June, 1993. All of the above are pre-Hispanic settlements located in tropical forest with no immigrations for over 50 years. Of the 440 indigenous Mayans, only one woman from the X'calot tribe (0.23%) was shown to be infected with HTLV-II. A high percentage of indeterminate results was found (22/439, 5%), three of which were accounted for by the husband and two children of the positive female case. PCR analysis followed by specific restriction digestion demonstrated the virus to be of the HTLV-IIb subtype, similar to that described in the Guaymi Indians from Panama. The presence of HTLV-II in the Mayan ethnos, and in other Amerindian populations supports the idea that HTLV-II is an ancestral virus in America and that it has been sustained in "closed" communities.

PIP: Although not consistently associated with any specific disease, infection with HTLV-II is nonetheless endemic among Amerindians, with a prevalence of 0.89-33%. Findings are presented from a study conducted to determine the prevalence of HTLV-II among indigenous Mayans in the Yucatan Peninsula of Mexico. 440 indigenous Mayans were recruited, all native to and residents of 1 of 6 Mayan communities in the Yucatan Peninsula between May 1992 and June 1993. All participants were drawn from pre-Hispanic settlements located in tropical forest without immigration for more than 50 years. Of the 440 subjects, only 1 woman from the X'calot tribe (0.23%) was found to be infected with HTLV-II. However, 22 of the remaining 439 (5%) results were indeterminate, of which 3 were accounted for by the husband and 2 children of the positive female case. Polymerase chain reaction analysis determined the virus to be of HTLV-IIb subtype, similar to that described among the Guaymi Indians of Panama. These findings support the argument that HTLV-II is an ancestral virus in America and that it has been sustained in closed communities.

[Lymphotropic viruses type I and II in pregnant women in Yucatán]. / Virus linfotrópicos tipos I y II en mujeres gestantes de Yucatán.

No antibodies against HTLV-I and HTLV-II were detected in 590 gestating women residing in the Yucatan peninsula sampled between Jan/92 and May/93.

Hairy cell leukemia is infrequent in México and has a geographic distribution.

Considering that the prevalence of some hematologic malignancies may have a geographic distribution that could be related with its etiology, a group of 2,387 patients with acute leukemia (1,968 adults and 419 children) was studied along a 5-year period in six different locations within México. Twenty-seven patients (16 males and 11 females) with hairy cell leukemia (HCL) were identified. The adjusted overall proportion of HCL, after excluding data from centers reporting only adults, was 1.12% of all leukemia cases; this figure is lower than that reported in the United States or England. The proportion of adult leukemic patients with HCL was significantly higher in the northern region of the country-where there are more people devoted to farming and agricultural activities-as compared with the central or southeastern regions (3.07 vs. 1.03% vs. 0%; P < 0.05); possible explanations for these differences are briefly discussed.

[Infection by human T-cell lymphotropic virus type I/II in polytransfused patients in the state of Yucatán, Mexico]. / Infección por el virus linfotrópico de células T humanas tipo I/II en pacientes politransfundidos en el estado de Yucatán, México.

The relationship between several disorders, including adult T-cell leukaemia, and HTLV I/II virus infection has been clearly demonstrated. In order to assess the prevalence of such viral infection in a group of multiple-transfusion patients in the State of Yucatan, Mexico, a study was carried out on 140 patients with anti-HTLV-I/II antibodies demonstrated by ELISA and sensitized particles agglutination test. The patients had received 447 units of blood or blood components as a whole, and the mean time elapsed between the transfusion and the study was 2.5 years (range, 0.5-40), other risks of infection being discarded. No HTLV I/II reactivity was found along this study, thus showing the low prevalence and scarce risk for the transmission of this disease in Yucatan.

Chromosomic findings in patients with paroxysmal nocturnal hemoglobinuria.

The chromosomes of 14 patients (9 males, 5 females) suffering from paroxysmal nocturnal hemoglobinuria in Merida, Mexico between April 1989 and July 1992 were analyzed. Four of the patients were children (range, 3-15 years old) and 9 were adults (range, 19-62 years old). None of the patients had any evidence of leukemic transformation and 9 of them had antecedent insecticide exposure. In 50%, the clinical presentation was anemia plus hemorrhagic syndrome. Only 1 case had thrombosis. The lapse between the beginning of the disease and the karyotypic analysis was 14.5 months on average (range, 1-172 months). In all cases we found a normal chromosomic complement. In addition, 5 patients had an acentric fragment in only 1 metaphase and one of these had a mar and Cq chromatid break in another metaphase, but neither could be considered as specific chromosomal abnormality for paroxysmal nocturnal hemoglobinuria.

Human T lymphotropic virus type II (HTLV-II) infection among female prostitutes in Yucatan, Mexico.

The antibodies to human T-lymphotropic virus type I/II (HTLV-I/II) were determined in non-intravenous drug-using female prostitutes from Merida Yucatan, Mexico. Serum specimens from 282 female prostitutes collected during 1990 were tested initially by enzyme immunoassay and further confirmed by western blot assays. Of these, 5 (1.8%, 95% confidence interval 0.2 to 3.3) were shown to be HTLV-I/II positive (reactivity to p24gag and gp68/r21eenv). All five specimens were shown to be infected with HTLV-II by immunoassays using type-specific synthetic peptides and recombinant proteins. Long-term cell lines developed from two individuals demonstrated active viral replication and were of CD8 phenotype. Polymerase chain reaction analysis from four of these five prostitutes demonstrated HTLV-II-specific amplification of all four specimens, of which one was subtype a (HTLV-IIa) and three were subtype b (HTLV-IIb). These data show that HTLV-II is the predominant HTLV type among female prostitutes from the Yucatan.

Evidence for mother-to-child transmission of human T lymphotropic virus type II.

Serologic analysis of the children of 2 married human T lymphotropic virus type II (HTLV-II)-infected prostitutes demonstrated antibodies to HTLV-II in an 8-year-old boy whose only recognizable risk for HTLV-II infection was breast-feeding during his first 4 years of life. Limited sequence analysis of isolates infecting the mother and child demonstrated 100% identical sequences in the long terminal repeat (LTR65-297; 236 bp), pol4762-4919 (157 bp), and env5523-6003 (480 bp) regions (both isolates were subtype a), suggesting mother-to-child transmission. In contrast, isolates obtained from 2 other prostitutes from the same geographic region had sequences different from those of the first woman and her child, and the second and third women were infected with HTLV-II subtype b. Although vertical transmission of HTLV-II in this 8-year-old child cannot be conclusively ascertained, the probability is overwhelming that infection occurred through breast-feeding for an extended period of time.

Immune responsiveness to the immunodominant recombinant envelope epitopes of human T lymphotropic virus types I and II in diverse geographic populations.

The heterogeneity of immune responsiveness to the immunodominant epitopes of human T lymphotropic virus (HTLV) types I (MTA-1(162-209)) and II (K-55(162-205)) were determined in natural infections with HTLV-I and -II from diverse geographic areas (n = 285). Of the HTLV-I specimens confirmed by polymerase chain reaction (PCR), all North American (n = 37) and Peruvian (n = 19) specimens reacted with MTA-1. Of HTLV-II specimens confirmed by PCR, 44 (96%) of 46 from North American blood donors, 28 (97%) of 29 from native Americans, and all from intravenous drug users (n = 29) reacted with K-55. Specimens from other geographic areas (Peru, 30; Brazil, 4; Mexico, 10; Italy, 5; Somalia, 13; Ethiopia, 17; Japan, 32; and Jamaica, 15) all reacted either with MTA-1 or K-55. By synthetic peptide-based serologic typing, all of these specimens could be typed as HTLV-I or -II. In addition to the direct implications of these findings for diagnostic purposes, these data provide indirect evidence for the conservation of immunodominant HTLVenv epitopes in diverse geographic populations.

TAR-like syndrome in a consanguineous Mayan girl.

We report on a 3-month-old girl with a TAR-like syndrome. Her older brother died with a similar disorder at 3 months of unknown causes. The parents are second cousins of Mayan ancestry. The infant also had, in addition to the usual abnormalities of TAR syndrome, depressed nasal bridge, cataracts, glaucoma, megalocorneae, and blue sclerae.

[Heterosexual transmission of the type I human inmmunodeficiency virus in a group of couples residing in the Yucatán peninsula]. / Transmisión heterosexual del virus de la inmunodeficiencia humana tipo I en un grupo de parejas residentes de la península de Yucatán.

OBJECTIVE: To ascertain the prevalence of type 1 human immunodeficiency virus (HIV-1) and to examine the factors associated with its transmission in a group of heterosexual couples. DESIGN: Prospective study, descriptive, from September 1985 to December 1989. SITE. A university research center and a private general hospital in the city of Merida, State of Yucatan. PATIENTS: Twenty-one adult patients (17 men and four women) with initial diagnosis of HIV-1 infection and their respective spouses. All the subjects were residents of the Yucatan peninsula. INTERVENTIONS: The diagnosis of HIV-1 infection was made by the detection of antibodies against HIV-1 (by ELISA and Western Blot). Both the HIV-1 infection and the stage of AIDS were defined by the CDC criteria. The following factors were evaluated in order to define whether any were associated with the risk of transmission of HIV-1: marital status, time of marital status, type of sexual practices, average number of episodes of sexual intercourse per month, stage of HIV-1 infection of the case, presence of sexually transmitted diseases, and presence of genital ulcers. RESULTS: Bisexuality was documented in 15 of the 17 males, and in two heterosexual relations with prostitutes was found. The female cases were infected by transfusion (two cases), intravenous drug addiction (one case) and prostitution (one case). Seventeen cases (81%) fulfilled the criteria for AIDS with diagnosis of HIV-1 infection HIV-1 was detected in eight out of 17 female spouses (47%) but not in the four male spouses. No relation was found between the variables and HIV-1 infection. CONCLUSIONS: The presence of heterosexual transmission of HIV-1 in this study was 38%. The absence of associated factors suggests that heterosexual relations with an infected subject is sufficient for the transmission of HIV-1 to occur. The limited number of female cases makes it difficult to evaluate the efficiency of female-male transmission. Bisexual practices were the predominant cause of HIV-1 infection in the male cases, and as a consequence, the indirect cause of HIV infection in the female spouses.