Multidrug- and isoniazid-resistant tuberculosis in three high HIV burden African regions.

SETTING: Despite major progress in the surveillance of drug-resistant tuberculosis (TB), data are lacking for many low-resource countries. World Health Organization estimates of multidrug-resistant TB (MDR-TB) rates in Africa are low, and based on very limited data from the African continent. OBJECTIVE: To measure MDR-TB prevalence in sub-Saharan African regions with a high prevalence of human immunodeficiency virus (HIV). METHOD: We conducted three anti-tuberculosis drug resistance surveys in sub-Saharan African regions with high HIV-TB coinfection prevalence: Homa Bay (Kenya), Chiradzulu (Malawi) and West Nile region (Uganda). RESULTS: The prevalence of MDR-TB in new patients was found to be low in the three regions: 1.4% (95%CI 0.2-2.6) in Homa Bay, 2.0% (95%CI 0.4-3.6) in Chiradzulu and 0.6% (95%CI 0.0-1.5) in the West Nile region. We found no significant association between MDR-TB and HIV infection. Nonetheless, ≥ 10% of the new cases surveyed were resistant to isoniazid (INH). CONCLUSION: The relatively high rate of resistance to INH highlights the need for rapid detection of INH resistance in addition to rifampicin (RMP) resistance, to allow rapid modification of treatment to avoid the acquisition of RMP resistance. Drug resistance should be monitored periodically.

Short communication: antituberculosis drug-induced hepatotoxicity is unexpectedly low in HIV-infected pulmonary tuberculosis patients in Malawi.

The proportion of patients with antituberculosis drug-induced hepatotoxicity (ATDH) was unexpectedly low during a trial on cotrimoxazole prophylaxis in Malawian HIV-positive pulmonary tuberculosis patients. About 2% of the patients developed grade 2 or 3 hepatotoxicity during tuberculosis (TB) treatment, according to WHO definitions. Data on ATDH in sub-Saharan Africa are limited. Although the numbers are not very strong, our trial and other papers suggest that ATDH is uncommon in this region. These findings are encouraging in that hepatotoxicity may cause less problem than expected, especially in the light of combined HIV/TB treatment, where drug toxicity is a major cause of treatment interruption.

Unacceptably high mortality related to measles epidemics in Niger, Nigeria, and Chad.

BACKGROUND: Despite the comprehensive World Health Organization (WHO)/United Nations Children's Fund (UNICEF) measles mortality-reduction strategy and the Measles Initiative, a partnership of international organizations supporting measles mortality reduction in Africa, certain high-burden countries continue to face recurrent epidemics. To our knowledge, few recent studies have documented measles mortality in sub-Saharan Africa. The objective of our study was to investigate measles mortality in three recent epidemics in Niamey (Niger), N'Djamena (Chad), and Adamawa State (Nigeria). METHODS AND FINDINGS: We conducted three exhaustive household retrospective mortality surveys in one neighbourhood of each of the three affected areas: Boukoki, Niamey, Niger (April 2004, n = 26,795); Moursal, N'Djamena, Chad (June 2005, n = 21,812); and Dong District, Adamawa State, Nigeria (April 2005, n = 16,249), where n is the total surveyed population in each of the respective areas. Study populations included all persons resident for at least 2 wk prior to the study, a duration encompassing the measles incubation period. Heads of households provided information on measles cases, clinical outcomes up to 30 d after rash onset, and health-seeking behaviour during the epidemic. Measles cases and deaths were ascertained using standard WHO surveillance-case definitions. Our main outcome measures were measles attack rates (ARs) and case fatality ratios (CFRs) by age group, and descriptions of measles complications and health-seeking behaviour. Measles ARs were the highest in children under 5 y old (under 5 y): 17.1% in Boukoki, 17.2% in Moursal, and 24.3% in Dong District. CFRs in under 5-y-olds were 4.6%, 4.0%, and 10.8% in Boukoki, Moursal, and Dong District, respectively. In all sites, more than half of measles cases in children aged under 5 y experienced acute respiratory infection and/or diarrhoea in the 30 d following rash onset. Of measles cases, it was reported that 85.7% (979/1,142) of patients visited a health-care facility within 30 d after rash onset in Boukoki, 73.5% (519/706) in Moursal, and 52.8% (603/1,142) in Dong District. CONCLUSIONS: Children in these countries still face unacceptably high mortality from a completely preventable disease. While the successes of measles mortality-reduction strategies and progress observed in measles control in other countries of the region are laudable and evident, they should not overshadow the need for intensive efforts in countries that have just begun implementation of the WHO/UNICEF comprehensive strategy.

Optimized deglycosylation of glycoproteins by peptide-N4-(N-acetyl-beta-glucosaminyl)-asparagine amidase from Flavobacterium meningosepticum.

Peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F(PNGase F) from Flavobacterium meningosepticum is a highly useful enzyme for the structural analysis of N (asparagine)-linked carbohydrate chains derived from glycoproteins. The enzyme was enriched using a published procedure [Tarentino AL, Gomez CM, Plummer TH, Jr (1984) Biochemistry 1985:4665-71; Tarentino AL, Plummer TH, Jr (1987) Methods Enzymol 138:770-78] and further purified by hydrophobic interaction HPLC on a weak hydrophobic TSK-Ether column from which it was eluted by a decreasing gradient of 1.7 M ammonium sulphate in 100 mM sodium phosphate, pH 7.0, containing 5 mM EDTA. To determine the optimal conditions for a complete deglycosylation of glycoproteins by PNGase F, experiments were performed with human alpha 1-acid glycoprotein, because the five complex type carbohydrate chains are quite resistant to enzymic hydrolysis. The influence of different detergents on the enzyme reaction was studied. Complete deglycosylation of human alpha 1-acid glycoprotein was achieved by the use of 60 mU/ml PNGase F in 0.25 M sodium phosphate buffer, pH 8.6, containing 0.2% (w/v) SDS, 20 mM mercaptoethanol and 0.5% Mega-10.