Prevalence of human T-cell lymphotropic virus type 1 infection in hospitalized patients with tuberculosis.

OBJECTIVE: Reports have suggested that human T-cell lymphotropic virus type 1 (HTLV-1) may influence immunological response and therefore the clinical course of tuberculosis (TB) in co-infected individuals. We wished to determine the prevalence of HTLV-1 infection among hospitalized patients in Salvador, Brazil, a region endemic for both HTLV-1 infection and latent TB infection. DESIGN: A cross-sectional study was conducted at a pulmonary disease hospital between 1 September 2006 and 31 August 2007. Study participants were interviewed and tested for HTLV-1 infection and current or past episode of TB. RESULTS: Of 607 participants recruited into the study, 360 (59.3%) had a current or past history of TB and 50 (8.2%) had HTLV-1 infection; 39 (6.4%) had both. After controlling for confounding variables, we found that the odds of patients with a positive HTLV-1 test having TB were 2.6 times the odds in those who tested negative for HTLV-1 infection (95%CI 1.2-5.4). CONCLUSION: In a region endemic for both TB and HTLV-1 infection, HTLV-1 infection increases the risk of Mycobacterium tuberculosis infection. Such a risk may influence TB transmission and the epidemiology of the disease in this community.

Effect of perinatal asphyxia on thyroid-stimulating hormone and thyroid hormone levels.

AIM: To compare serum concentrations of thyroid hormones--T4, T3, free T4 (FT4) and reverse T3 (rT3)--and thyroid-stimulating hormone (TSH) found in the umbilical cord blood of term newborns with and without asphyxia and those found in their arterial blood collected between 18 and 24 h after birth. A further aim of the study was to assess the association between severity of hypoxic-ischemic encephalopathy and altered thyroid hormone and TSH levels, and between mortality and FT4 levels in the arterial blood of newborns between 18 and 24 h of life. METHODS: A case-control study was carried out. The case group comprised 17 term newborns (Apgar score < or = 3 and < or = 5 at the first and fifth minutes; umbilical cord blood pH < or = 7.15) who required bag and mask ventilation for at least one minute immediately after birth. The control group consisted of 17 normal, term newborns (Apgar score > or = 8 and > or = 9 at the first and fifth minutes; umbilical cord blood pH > or = 7.2). Cord blood and arterial blood samples were collected immediately after birth and 18 to 24 h after birth, respectively, and were used in the blood gas analysis and to determine serum concentrations of T4, T3, FT4, rT3 and TSH by radioimmunoassay. All newborns were followed-up until hospital discharge or death. RESULTS: Gestational age, birthweight, sex, size for gestational age, mode of delivery and skin color (white and non-white) were similar for both groups. No differences were found in mean levels of cord blood TSH, T4, T3 and FT4 between the groups. In the samples collected 18 to 24 h after birth, mean levels of TSH, T4, T3 and FT4 were significantly lower in the asphyxiated group than in the control group. Mean concentrations of arterial TSH, T4 and T3 between 18 and 24 h of life were lower than concentrations found in the cord blood analysis in asphyxiated newborns, but not in controls. In addition, asphyxiated newborns with moderate/severe hypoxic-ischemic encephalopathy presented significantly lower mean levels of TSH, T4, T3 and FT4 than those of controls. None of the asphyxiated newborns with FT4 > or = 2.0 ng/dl died; 6 out of the 11 asphyxiated newborns with FT4 < 2.0 ng/dl died. CONCLUSIONS: Serum concentrations of TSH, T4, T3 and FT4 are lower in asphyxiated newborns than in normal newborns between 18 and 24 h of life; this suggests central hypothyroidism secondary to asphyxia. Asphyxiated newborns with moderate/severe hypoxic-ischemic encephalopathy present a greater involvement of the thyroid function and consequently a greater risk of death.

[Effect of perinatal asphyxia on thyroid hormones] / Efeitos da Asfixia Perinatal sobre os Hormônios Tireoidianos.

OBJECTIVE: To verify the effect of perinatal asphyxia on thyroid hormone levels in term newborn infants. METHODS: We carried out a case-control study with 17 term and asphyxiated (A) and 17 term and control (N) newborn infants at the Hospital de Clínicas de Porto Alegre. Patients were paired according to color of skin, sex, type of delivery, gestational age, and weight at birth. We collected umbilical cord plasma T4, T3, free T4, reverse T3, and TSH after 18 to 24 hours of life and from asphyxiated and control newborn infants. RESULTS: There were no differences in thyroid hormones of cord blood, with the exception of reverse T3, which was higher in A than in controls [median (25th-75th percentile): A= 2(1.4-2); N= 1.41 (1.13-1.92); P=0.037)]. Thyroid hormone levels were lower in A than in controls on samples collected within 18-24 hours after birth, except for reverse T3, which was similar in both groups [average -/+ SD: T4 A= 9.79 -/+ 2.59; N=14.68 -/+ 3.05; P<0.001; median T3 A= 40.83 (37.4-80.4); N= 164 (56.96-222.5); P=0.003; average -/+ SD: free T4 A=1.85 -/+ 0.92; N= 2.8 -/+ 0.74; P=0.004; median: reverse T3 A=1.54 (1.16-1.91); N=1.31(0.87-2); P=0.507; TSH A=9.1 (6.34-12.95); N=14.5(12.9-17.85); P=0.008]. CONCLUSIONS: Our data suggest that lower T4, free T4, and T3 levels are secondary to lower TSH levels in asphyxiated newborns; also, peripheral metabolism of T4 in asphyxiated infants can be altered due to low T3 and normal reverse T3 levels.

[Clinical manifestations in term newborn infants with different degrees of acidemia in umbilical cord blood] / Manifestações clínicas em recém-nascidos a termo com diferentes graus de acidemia no sangue de cordão umbilical.

OBJECTIVE: To verify if Apgar score plus umbilical cord pH are adequate to predict which newborn infant will develop multiorgan system disfunction. METHODS: A study including all term newborn infants with Apgar scores in the first and fifth minutes of life < 7 and umbilical cord blood pH < 7.20 born in Hospital de Clínicas de Porto Alegre from March 1995 through March 1998 was performed. Venous umbilical cord blood was collected for blood gas analysis. Newborn infants were divided in two groups: Group A with pH < 7.0, and Group B with pH >/= 7.0 and < 7.20. Patients were evaluated for the presence of pulmonary hypertension, renal failure, inappropriate secretion of antidiuretic hormone, ischemic cardiopathy, early seizures, neurologic injury at hospital discharge and death. RESULTS: Twenty five newborn infants were included in the study.Twelve formed Group A, and 13, Group B. There were no differences between both groups in respect to mode of delivery, gender, color and birth weight. Group B had a lower gestational age than Group A. There were significant differences between both groups in mean cord blood pH, pCO(2) and BE (p<0.05). There was a positive association between umbilical cord blood pH and Apgar score. Higher occurrence of neurologic injury at hospital discharge in Group A was the only statistically significant clinical manifestation (p<0.05). CONCLUSION: Apgar score and umbilical cord pH are not adequate criteria to predict multiorgan system dysfunction.

Transient elevation of aldosterone levels in perinatal asphyxia.

We measured plasma aldosterone levels in cord blood and peripheral blood collected 18-24 h after birth in 19 asphyxiated and 19 normal term newborn infants. The asphyxiated newborn infants had significantly higher aldosterone levels in cord blood than the normal newborn infants. At 18-24 h after birth there was no difference between the groups with respect to aldosterone levels. There was a positive significant correlation between aldosterone levels and PCO2 in cord blood by multiple linear regression analysis. There is a transient elevation of aldosterone levels in perinatal asphyxia.

[Evaluation of umbilical cord pH and its relationship with Apgar score in term newborn infants]. / Avaliação do pH de sangue de cordão umbilical e sua relação com o escore de Apgar em recém-nascidos a termo.

The value of the Apgar score as an index of birth asphyxia has been recently questioned. The purpose of the present study is to evaluate the relationship between cord blood pH and Apgar score in term newborn infants.A cross-sectional study involving 76 term newborn infants was performed from March through September 1995 at the Obstetric Unit of Hospital de Clínicas de Porto Alegre. The blood samples were obtained from umbilical cord artery and vein at the moment of delivery. Infants were divided in three different groups according to the Apgar score: Group A (n=60): >or=7 at one and five minutes; Group B (n=13): < 7 at one minute and >or=7 at five minutes; Group C (n=3): < 7 at one and five minutes. The frequency of acidemia in Group A was 18.3% (11 newborn infants) considering arterial pH < 7.20 and 5% considering arterial pH or= 7.20 and nine (56.2%) had arterial pH > 7.10. None of the newborn infants in Group C had arterial pH > 7.10. The sensitivity and specificity values for Apgar score less than 7 at one minute for detection of fetal acidemia were, respectively, 54.1% and 94.1%. This study confirms a poor correlation between Apgar score and umbilical blood cord pH, even in a term newborn, and emphasizes the importance of obtaining umbilical cord pH to consider the diagnosis of perinatal asphyxia.