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Background: Low hemoglobin (Hb) and iron deficiency among child bearing females have been linked to decreased immune system function, impaired cognitive functioning and complications in pregnancy. Methods: A total of 106 blood samples from apparently healthy nulliparous female students were assayed for Hb and serum iron concentrations using the cyanmethemoglobin and bathophenanthroline methods, respectively, to evaluate changes that may occur in these parameters at different phases of the reproductive cycle. Results: The mean (SD) Hb values during the ovulatory, menstrual, and follicular phases were 13.27 (1.14) g/dL, 12.05 (1.31) g/dL, and 12.23 (1. 56) g/dL, respectively. The prevalence of anemia (Hb<12 g/dL) was reported among 21 (19.8%) subjects, and 31 subjects declined to complete their samples collection. The mean serum iron concentrations during the 3 phases were 92.98 (18.25) μg/dL, 79.90 (13.14) μg/dL and 70.85 (18.65) μg/dL, respectively. A total of 28 (26.4%) study participants showed iron deficiency (serum level, <65 μg/dL). These variations in the values of Hb and serum iron concentrations were statistically significant in the 3 phases. However, no significant difference was observed in Hb concentrations between the menstrual and follicular phases. Of interest, a positive correlation was observed between the hemoglobin and serum iron concentrations within the phases, with the exception of a few cases that showed negative correlations. Conclusion: Menstruation has been shown to be the major cause of anemia and iron deficiency in nulliparous women. A prophylactic dose of iron and folate supplements may be indicated for menstruating females to cushion the adverse effects of menstruation on ematologic status. [ABSTRACT FROM AUTHOR]

Summary: Commercial tests measuring IFN-γ responses to ESAT-6 and CFP-10 are available for diagnosing Mycobacterium tuberculosis infection. Measures that minimize cost and complexity will facilitate their application in less-developed countries. We investigated whether overlapping peptides representing both ESAT-6 and CFP-10 are required to detect M. tuberculosis infection in a high TB-burden country, and whether they can be combined in a single pool. ESAT-6 and CFP-10 peptides were compared in IFN-γ enzyme-linked immunospot (ELISPOT) in 183 HIV-negative smear-positive TB cases and 1673 HIV-negative household contacts. Separate peptide pools for each antigen were compared with a combined pool in 498 contacts. Forty per cent of responsive contacts recognized both antigens, 51% only ESAT-6 and 10% only CFP-10, whereas 56% of responsive cases recognized both antigens, 30% only ESAT-6 and 13% only CFP-10. Accordingly, CFP-10 response rates were higher for TB cases (odds ratio 2.409, P <0.001). Low purified protein derivative response rates indicated that responses to CFP-10 only were non-specific in contacts. Agreement between peptides in separate versus combined pools was good (κ=0.758, r =0.840). Therefore a combined ESAT-6/CFP-10 peptide pool provided maximum sensitivity and efficiency, but CFP-10 was mainly required to detect active disease. [Copyright &y& Elsevier]

Summary: Contact investigation is a key component of tuberculosis (TB) control in developed, but not developing, countries. We aimed to measure the prevalence of TB among household contacts of sputum-smear-positive TB cases in The Gambia and to assess the sensitivity of an enzyme-linked immunospot (ELISPOT) assay in this regard. Household contacts of adult smear-positive TB patients were assessed by questionnaire, purified protein derivative (PPD) skin test, ELISPOT assay, physical examination, chest X-ray and sputum/gastric aspirate. Thirty-three TB cases were identified from 2174 of 2381 contacts of 317 adult smear-positive pulmonary TB patients, giving a prevalence of 1518/100000. The cases identified tended to have milder disease than those passively detected. The sensitivity of ESAT-6/CFP-10 ELISPOT test as a screening test for TB disease was estimated as 71%. Fifty-six per cent of contacts with a PPD skin test result ≥10mm induration had detectable responses to ESAT-6/CFP-10 by ELISPOT; 11% with a negative PPD skin test (<10mm) had a positive ESAT-6/CFP-10 response. Active screening for TB among contacts of TB patients may have a role in TB control in The Gambia. These individuals are a high-risk group, and the disease identified is less advanced than that found through passive case detection. An ELISPOT assay was relatively insensitive as a screening test for TB. [Copyright &y& Elsevier]

Background. Currently, reliable efficacy markers for assessment of new interventions against tuberculosis (TB) are limited to disease and death. More precise measurement of the human immune response to Myco bacterium tuberculosis infection may be important. A qualitative enzyme-linked immunospot assay (ELISPOT) result for early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP- 10) offers improved specificity over the purified protein derivative (PPD) skin test reaction in the detection of M. tuberculosis infection. We evaluated the quantitative ELISPOT and PPD skin test responses to recent M. tuberculosis exposure. Methods. We studied quantitative PPD skin test and PPD ELISPOT results in 1052 healthy household contacts of index patients with cases of sputum smear-positive and culture-positive TB in The Gambia, according to a positive or negative ex vivo interferon γ ELISPOT response to M. tuberculosis-specific antigens (ESAT-6/CFP-10). We then studied the quantitative PPD skin test and PPD ELISPOT results in patient contacts who had positive ESAT-6/CFP-10 results against a natural exposure gradient according to sleeping proximity to a patient with TB. Results. The number of positive results was significantly greater for both PPD skin test and PPD ELISPOT in ESAT-6/CFP- 10-positive subjects, compared with others (P<.0001). However, when quantitative PPD skin test and PPD ELISPOT results were compared in ESAT-6/CFP-10-positive subjects, only the ELISPOT count was sensitive to the exposure gradient, increasing significantly according to exposure (P = .009). Conclusions. The quantitative ELISPOT response to PPD in specific-antigen-positive contacts of patients with TB reflects the infectious load of M. tuberculosis as a result of recent exposure. This finding offers new possibilities for assessment of the efficacy of new interventions, and adjustment should be made for it when relating the early immune response to progression to disease. [ABSTRACT FROM AUTHOR]

The purified protein derivative (PPD) skin test for Mycobacterium tuberculosis infection lacks specificity. We assessed 2 more specific M. tuberculosis antigens (ESAT-6 and CFP-10) by enzyme-linked immunospot assay (ELISPOT) compared with PPD by ELISPOT and skin test in The Gambia. Of 735 household contacts of 130 sputum smear–positive tuberculosis cases, 476 (65%) tested positive by PPD ELISPOT, 300 (41%) tested positive by PPD skin test, and 218 (30%) tested positive by ESAT-6/CFP-10 ELISPOT. Only 15 (2%) had positive ESAT- 6/CFP-10 results and negative PPD results by ELISPOT. With increasing M. tuberculosis exposure, the percentage of subjects who were PPD skin test positive/ESAT-6/CFP-10 ELISPOT negative increased (P < .001) whereas the percentage of subjects who were PPD skin test negative/PPD ELISPOT positive decreased (Pp ). Eighteen (31%) SAT-6/CFP-10 ELISPOT–positive subjects in the lowest exposure category had negative .011 PPD skin test results. ESAT-6/CFP-10 ELISPOT probably offers increased specificity in the diagnosis of M. tuberculosis infection in this tropical setting of endemicity, at the cost of some sensitivity. [ABSTRACT FROM AUTHOR]