Prevalence of Group A beta-haemolytic Streptococcus isolated from children with acute pharyngotonsillitis in Aden, Yemen.

OBJECTIVES: To estimate the prevalence of Group A beta-haemolytic streptococcus (GAS) and non-GAS infections among children with acute pharyngotonsillitis in Aden, Yemen, to evaluate the value of a rapid diagnostic test and the McIsaac score for patient management in this setting and to determine the occurrence of emm genotypes among a subset of GAS isolated from children with acute pharyngotonsillitis and a history of acute rheumatic fever (ARF) or rheumatic heart disease (RHD). METHODS: Group A beta-haemolytic streptococcus infections in school-aged children with acute pharyngotonsillitis in Aden, Yemen, were diagnosed by a rapid GAS antigen detection test (RADT) and/or GAS culture from a throat swab. The RADT value and the McIsaac screening score for patient management were evaluated. The emm genotype of a subset of GAS isolates was determined. RESULTS: Group A beta-haemolytic streptococcus pharyngotonsillitis was diagnosed in 287/691 (41.5%; 95% CI 37.8-45.3) children. Group B, Group C and Group G beta-haemolytic streptococci were isolated from 4.3% children. The RADT had a sensitivity of 238/258 (92.2%) and specificity of 404/423 (95.5%) against GAS culture. A McIsaac score of ≥4 had a sensitivity of 93% and a specificity of 82% for confirmed GAS infection. The emm genotypes in 21 GAS isolates from children with pharyngitis and a history of ARF and confirmed RHD were emm87 (11), emm12 (6), emm28 (3) and emm5 (1). CONCLUSION: This study demonstrates a very high prevalence of GAS infections in Yemeni children and the value of the RADT and the McIsaac score in this setting. More extensive emm genotyping is necessary to understand the local epidemiology of circulating strains.

Prevalence of rheumatic heart disease among school-children in Aden, Yemen.

BACKGROUND: Rheumatic heart disease (RHD) is an important contributor to cardiovascular disease in children and adults in Yemen. This is the first report to determine the prevalence of RHD among school-children in the city of Aden. METHODS: A cross-sectional case-finding survey of RHD was conducted in 6000 school-children aged 5-16 years. Echocardiography was undertaken in those with clinical signs of organic heart disease. RESULTS: The prevalence of RHD was 36·5/1000 school-children, which is one of the highest reported among school echocardiography surveys in the world. RHD was more common in 10-16-year-old students. RHD was diagnosed in more than one member of the families of 53 (24·2%) of the children. Mitral regurgitation (MR) was detected in 49·8%, 26·6% had MR with mitral valve prolapse and 17·8% had combined MR and aortic regurgitation. Fifty-eight children were diagnosed with congenital heart disease (CHD), representing a prevalence of 9·7/1000. The main types of CHD were mitral valve prolapse, patent ductus arteriosus, atrial septal defect, pulmonary stenosis and aortic stenosis. Congenital mitral valve prolapse found in 36 children was three times more common in males than females. Children with RHD were more likely to be from low-income families with poor housing and greater overcrowding (49·3%, 39·3% and 64·8%) than children with CHD (44·8%, 32·8% and 48·3%, respectively). CONCLUSIONS: The high prevalence of RHD is a major public health problem in Yemen. Urgent screening surveys and an RHD prophylactic programme of appropriate management of group A ß-haemolytic streptococcal pharyngotonsilitis are required.

Ralph George Hendrickse.

Paediatrician and specialist in tropical child health. Born 5 November 1926 in Cape Town, South Africa, died 6 May 2010 in Heswall, Wirral, England, aged 83.

Diagnosis of pulmonary tuberculosis in young children.

The Stop TB Strategy encompasses promotion and support for childhood TB including diagnosis. The diagnosis of TB in low-income countries needs to be improved using existing technology. All hospitals involved in managing children with TB should have a regular stock of tuberculin. A chest radiograph (CXR) is an integral part of the diagnosis of pulmonary TB and hospitals should be able to take satisfactory CXRs of young children. If there is a reliable laboratory service, bacterial confirmation should be undertaken in selected cases. The laboratory should be able to deal satisfactorily with paediatric specimens. Gastric aspiration is the method of choice to obtain sputum from young children and generally produces higher yields than other methods, and, with good technique, results in outpatients may not be much lower than in inpatients. Nasopharyngeal aspiration is a simple alternative method requiring limited equipment. Sputum induction requires a special room, capital and recurrent equipment and a dedicated nurse. Laryngeal swabs are suitable for older outpatients unable to produce adequate sputum. Each hospital should have a clinician trained in the diagnosis and management of childhood TB, including the interpretation of CXRs and skill in fine-needle aspiration. Radiologists and clinicians should use a simple, clear, internationally accepted classification of paediatric CXRs. The clinician(s) in charge of TB services should oversee all inpatients with TB and be at the forefront in running the TB clinic. A TB nurse specialist(s) should be part of the team. There is now a will to improve the diagnosis and management of childhood TB but bringing it to fruition requires efforts by the local TB service, paediatricians, radiology departments and laboratory services.

Micronutrients and T-cell subsets: a comparison between HIV-infected and uninfected, severely malnourished Rwandan children.

OBJECTIVE: To determine the levels of CD4+ cells and micronutrients in HIV-infected and uninfected severely malnourished children. DESIGN: Cross-sectional study in two centres. SETTING: Children admitted to the malnutrition units in Kigali and Butare, Rwanda. PATIENTS: A total of 112 children aged 2 months to 5 years presenting with severe malnutrition (weight for height Z- score -3 SD +/- oedema). Fifty-two (46.4%) were HIV-infected. METHODS: CD4+ counts, selenium, zinc and copper levels were measured. The percentage of CD4 cells was calculated as a proportion of total lymphocyte count. RESULTS: The mean age of the 52 HIV-infected children (18 months) was lower than of the 60 uninfected children (26 months) (p=0.01). Six (11.5%) of the HIV-infected had oedematous malnutrition compared with 50% of the uninfected group. The mean (SD) CD4+ count was 1054 (780) in the HIV-infected and 1579 (721) in the uninfected group (p=0.001). The CD4+ count was also significantly lower in the HIV-infected group than in the uninfected group for the ages <12 mths (p=0.09), 12-24 mths (p=0.045) and >36 mths (p=0.001). In HIV-infected children, 17% had severe immunosuppression (<15% CD4+ cells), 33% moderate (15-24%) and 50% had none (>25%) compared with 9%, 12% and 80% in the HIV-uninfected group, respectively (p<0.001). Approximately one-third in both groups had low levels of selenium and zinc and 77% had raised levels of copper. In multivariate analysis there was significant correlation between selenium and CD4+ (r=0.36, p<0.001) in HIV-infected children and no correlation of zinc and copper to CD4+ %. In HIV uninfected children, CD4+ % was related to selenium (r=0.282, p=0.03) and to zinc (r=0.264, p=0.047) but not to copper. CONCLUSIONS: In severely malnourished children with HIV infection, low CD4+ levels are associated mainly with HIV infection. There was no significant difference in levels of selenium, zinc and copper between HIV-infected and uninfected children.

Nasopharyngeal aspiration for diagnosis of pulmonary tuberculosis.

BACKGROUND: Confirmation of pulmonary tuberculosis (PTB) in young children is difficult as they seldom expectorate sputum. AIM: To compare sputa obtained by nasopharyngeal aspiration and by sputum induction for staining and culture of Mycobacterium tuberculosis. PATIENTS AND METHODS: Patients from Mulago Hospital, Kampala with symptoms suggestive of PTB were considered for inclusion in the study. Those with a positive tuberculin test and/or a chest radiograph compatible with tuberculosis were recruited. Infection with human immunodeficiency virus (HIV) was confirmed by duplicate enzyme-labelled immunosorbent assay or in children <15 months by polymerase chain reaction (PCR). Direct PCR was undertaken on 82 nasopharyngeal aspirates. RESULTS: Of 438 patients referred, 94 were recruited over a period of 5 months. Median (range) age was 48 (4-144) months. Of 63 patients tested, 69.8% were infected with HIV. Paired and uncontaminated culture results were available for 88 patients and smear results for 94 patients. Nasopharyngeal aspirates were smear-positive in 8.5% and culture-positive in 23.9%. Induced sputa were smear-positive in 9.6% and culture positive in 21.6%. Overall, 10.6% were smear-positive, 25.5% were culture-positive and 26.6% had smear and/or culture confirmed tuberculosis. Direct PCR on nasopharyngeal aspirates had a sensitivity of 62% and specificity of 98% for confirmation of culture-positive tuberculosis. CONCLUSIONS: Nasopharyngeal aspiration is a useful, safe and low-technology method for confirmation of PTB and, like sputum induction, can be undertaken in outpatient clinics.

Comparison of urine contamination rates using three different methods of collection: clean-catch, cotton wool pad and urine bag.

Collecting uncontaminated urine specimens from infants is difficult. Commonly, an adhesive urinecollecting bag is used, which is uncomfortable. This study determined bacterial contamination rates using three methods of urine collection sequentially on the same infant (without known urinary tract infection)-clean-catch, cotton wool (sanitary) pad and urine bag. The study was undertaken in children under 3 years of age in the Institute of Maternal and Child Health of Pernambuco (IMIP), Recife, Brazil. Urine samples were analysed using phase contrast microscopy and routine culture. Culture of bacteria at any level was interpreted as a contaminated urine specimen. Cultures with > 10(5) colony-forming units/ml of one species by all three collection methods were regarded as true urinary tract infection and these children were excluded. Altogether, 534 urine samples from 191 patients were analysed. Median age was 2 months (1 day-36 months) and 124 (65%) were boys. Twelve children (6.3%) were considered to have true urinary tract infection, three were indeterminate and in 16 one or more samples were missing and all were excluded from analysis. There were more missing samples using the clean-catch method (12%) than when using the bag (4%) or pad (4%). Seventy-six of 160 (47.5%) children had evidence of bacterial contamination. Clean-catch specimens showed the least contamination (14.7%) and rates were similar between pads (29%) and bags (26.6%) (kappa = 0.40). Urine contamination rates were similar for sanitary pads and urine bags and significantly higher than for clean-catch (p<0.01). However, pads were a simple, non-invasive and comfortable alternative to bags.

Childhood tuberculosis: clinical research needs.

Childhood tuberculosis (TB) is common in the developing world, where over 90% of global TB cases occur, and has increased in human immunodeficiency virus (HIV) endemic regions. Most children with TB are not infectious, and so, from a public health perspective, are not afforded the same priority by TB control programmes as older age groups in settings of limited resources. In addition, the diagnosis of pulmonary TB is particularly difficult in young children. This has resulted in TB being a neglected disease in children, although it causes substantial morbidity and mortality. This review summarises the current knowledge of clinical aspects of childhood TB management, and aims to identify priority areas for future research. The most critical need is for improved capability to confirm diagnosis. This would lead to better management of childhood TB and would greatly enhance our ability to conduct meaningful research in many related areas, including immunological studies which could lead to a more effective vaccine. Also important are a better understanding of risk factors for infection and disease, including the impact of HIV, and operational research to improve treatment outcomes and management of well childhood contacts.

HIV transmission through breastfeeding: problems and prevention.

The greatest burden of HIV infection in women and their children is disproportionately borne by the poorest countries, especially in sub-Saharan Africa. Breastfeeding is a major health-promoting factor for infants and children in developing countries but the risk of mother-to-child transmission (MTCT) of HIV by this route is challenging traditional practices and health policies in low-resource countries. Maternal and infant factors contributing to the risk of MTCT through breastfeeding are still poorly understood and not well researched. Factors identified include: advanced clinical stages of infection in the mother; high maternal plasma HIV-1 load; presence of mastitis; and infant oral thrush. In many developing countries, international agencies are providing support and recommendations for preventing MTCT of HIV-1 by breastfeeding. Preventive strategies supported by WHO/UNICEF and charitable agencies in some sentinel centres in sub-Saharan Africa include routine antenatal voluntary counselling and testing (VCT), PCR testing of infants of seropositive mothers at 6 weeks of age, various combinations of a shortened period (3-6 mths) of exclusive breastfeeding, perinatal administration of antiretrovirals (ARV) such as nevirapine and provision of affordable and safe infant replacement feeds (presently given free by UNICEF in some centres). Many problems, however, have hindered effective implementation of these interventions. In many poor communities, even where VCT facilities are available, acceptance of HIV testing is low because there is fear of stigmatisation by the spouse, family or community and compliance with complex drug regimens is therefore poor. Other problems include the exorbitant cost of antiretroviral drugs, inadequately resourced health care systems and unavailability or poor acceptance of safe breast-milk alternatives. The rate of mixed feeding is high and so the risk of MTCT is increased. Continued promotion of exclusive breastfeeding for at least 6 months, irrespective of HIV status, followed by a properly prepared, high energy, nutritious complementary diet, with the possibility of early weaning to an animal milk formula, still appears to be the most appropriate option for the poor in countries with high levels of MTCT not deriving any benefit from the above strategies. While a longer period of breastfeeding would probably increase the risk of MTCT in vulnerable communities, a shorter duration would certainly increase infant morbidity and mortality. Results of investigations of the efficacy of ARV for protecting the infants of HIV-infected mothers during the breastfeeding period are awaited.

Niemann-Pick disease: sixteen-year follow-up of allogeneic bone marrow transplantation in a type B variant.

Allogenic bone marrow transplantation (BMT) was carried out on a 3-year-old white caucasian girl with Niemann-Pick disease (NPD) type B. The donor was her unaffected brother. The patient was neurologically normal at the time of transplantation. Engraftment was based on cytogenetic studies and increased leukocyte acid sphingomyelinase (ASM) activity. However, liver biopsies taken up to 33 months post transplantation showed only a moderate reduction in stored sphingomyelin and no significant increase in ASM activity. The post-transplantation period was complicated by severe graft-versus-host disease and a respiratory arrest. By 6 years of age, neurological involvement was observed, including bilateral cherry red spots. The proband is now severely mentally and physically disabled. Liver cirrhosis has continued to progress despite the BMT, and haematemesis due to portal hypertension occurred at 17 years of age. However, pulmonary infiltration regressed after BMT and there has been no clinical evidence of pulmonary insufficiency.

The value of urine testing for verifying adherence to anti-tuberculosis chemotherapy in children and adults in Uganda.

SETTING: Mulago Hospital, Kampala, Uganda. OBJECTIVE: To evaluate the usefulness of urine dipsticks for monitoring adherence to anti-tuberculosis chemotherapy. DESIGN: In-house urine dipsticks for detection of isoniazid (INH) metabolites were compared to commercial test strips. The value of n-butanol to detect rifampicin was compared to coloration of the urine. Non-adherence was assessed through a questionnaire and reviews of the Mulago Hospital TB register. RESULTS: Urine was obtained from 236 patients (127 adults and 109 children) on daily chemotherapy. Using commercial test strips as standard, the sensitivity of in-house urine dipsticks was 99.5% and specificity was 96.4%. The sensitivity and the specificity of n-butanol and of coloration of urine to detect rifampicin were low (64.0% and 54.9%, and 85.5% and 64.8%, respectively). Fifty patients (21.2%) admitted non-adherence to treatment during the previous month. An additional 15 (6.8%) were detected through urine testing. Of 911 patients in the TB register of Mulago Hospital who had started treatment in the first 3 months of 2000, 39.7% did not complete their treatment. Two-thirds of these had discontinued treatment in the first 2 months. CONCLUSION: In-house INH test strips are as effective as commercially available strips for detecting isoniazid in the urine. They are a simple tool for monitoring adherence. Adherence to anti-tuberculosis chemotherapy as determined by the use of isoniazid test strips and review of the TB register showed poor compliance. Tests for rifampicin are less sensitive and specific.