Prevalence of symptoms of asthma, rhinitis and eczema in 13- to 14-year-old children in Africa: the International Study of Asthma and Allergies in Childhood Phase III

Phase I of the International Study of Asthma and Allergies in Childhood has provided valuable information regarding international prevalence patterns and potential risk factors in the development of asthma, allergic rhinoconjunctivitis and eczema. However, in Phase I, only six African countries were involved (Algeria, Tunisia, Morocco, Kenya, South Africa and Ethiopia). Phase III, conducted 5-6 years later, enrolled 22 centres in 16 countries including the majority of the centres involved in Phase I and new centres in Morocco, Tunisia, Democratic Republic of Congo, Togo, Sudan, Cameroon, Gabon, Reunion Island and South Africa. There were considerable variations between the various centres of Africa in the prevalence of the main symptoms of the three conditions: wheeze (4.0-21.5%), allergic rhinoconjunctivitis (7.2-27.3%) and eczema (4.7-23.0%). There was a large variation both between countries and between centres in the same country. Several centres, including Cape Town (20.3%), Polokwane (18.0%), Reunion Island (21.5%), Brazzaville (19.9%), Nairobi (18.0%), Urban Ivory Coast (19.3%) and Conakry (18.6%) showed relatively high asthma symptom prevalences, similar to those in western Europe. There were also a number of centres showing high symptom prevalences for allergic rhinoconjunctivitis (Cape Town, Reunion Island, Brazzaville, Eldoret, Urban Ivory Coast, Conakry, Casablanca, Wilays of Algiers, Sousse and Eldoret) and eczema (Brazzaville, Eldoret, Addis Ababa, Urban Ivory Coast, Conakry, Marrakech and Casablanca).

Cost-effectiveness of polymerase chain reaction versus Ziehl-Neelsen smear microscopy for diagnosis of tuberculosis in Kenya

BACKGROUND

Laboratory services, particularly in large sub-Saharan cities, are overstretched, and it is becoming difficult both for patients and health staff to adhere to the diagnostic procedures for tuberculosis. Alternative techniques would be welcome. The polymerase chain reaction (PCR) has the potential to be cost-effective. We compared the cost-effectiveness of two diagnostic strategies, Ziehl-Neelsen (ZN) on three specimens followed by chest X-ray (CXR), and AMPLICOR MTB PCR on the first specimen only.

METHODS

Three sputum samples were collected from tuberculosis (TB) suspects attending the Rhodes Chest Clinic, Nairobi. All samples were subjected to ZN, PCR and Löwenstein-Jensen culture used as gold standard. CXR was used to diagnose smear-negative TB. Cost analysis included health service and patient costs.

RESULTS

Costs per correctly diagnosed case were US dollar 41 and dollar 67 for ZN and PCR, respectively. When treatment costs were included, including treatment of culture-negative cases, PCR was more cost-effective: dollar 382 vs. dollar 412.

CONCLUSION

PCR may be an alternative in settings with many patients. PCR is patient friendly, CXR is not necessary and, unlike ZN, its performance is hardly affected by the human immunodeficiency virus. PCR can handle large numbers of specimens, with results becoming available on the same day.

Quality of glycaemic control in ambulatory diabetics at the out-patient clinic of Kenyatta National Hospital, Nairobi

BACKGROUND

Treatment of diabetes mellitus is based on the evidence that lowering blood glucose as close to normal range as possible is a primary strategy for reducing or preventing complications or early mortality from diabetes. This suggests poorer glycaemic control would be associated with excess of diabetes-related morbidity and mortality. This presumption is suspected to reach high proportions in developing countries where endemic poverty abets poor glycaemic control. There is no study published on Kenyan patients with diabetes mellitus about their glycaemic control as an audit of diabetes care.

OBJECTIVE

To determine the glycaemic control of ambulatory diabetic patients.

DESIGN

Cross-sectional study on each clinic day of a randomly selected sample of both type 1 and 2 diabetic patients.

SETTING

Kenyatta National Hospital.

METHODS

Over a period of six months, January 1998 to June 1998. During routine diabetes care in the clinic, mid morning random blood sugar and glycated haemoglobin (HbA1c) were obtained.

RESULTS

A total of 305 diabetic patients were included, 52.8% were females and 47.2% were males. 58.3% were on Oral Hypoglycaemic Agent (OHA) only, 22.3% on insulin only; 9.2% on OHA and insulin and 4.6% on diet only. 39.5% had mean HbA1c < or = 8% while 60.5% had HbA1c > or = 8%. Patients on diet-only therapy had the best mean HbA1c = 7.04% while patients on OHA-only had the worst mean HbA1c = 9.06%. This difference was significant (p=0.01). The former group, likely, had better endogenous insulin production. The influence of age, gender and duration of diabetes on the level of glycaemic control observed did not attain statistically significant proportions.

CONCLUSION

The majority of ambulatory diabetic patients attending the out-patient diabetic clinic had poor glycaemic control. The group with the poorest level of glycaemic control were on OHA-only, while best control was observed amongst patients on diet-only, because of possible fair endogenous insulin production. Poor glycaemic control was presumed to be due to sub-optimal medication and deteriorating diabetes. There is need to empower patients with knowledge and resources to enhance their individual participation in diabetes self-care. Diabetes care providers and facilities also need capacity building to improve care of patients with diabetes.

Pneumocystis carinii pneumonia in HIV/AIDS patients at an urban district hospital in Kenya

BACKGROUND

Pneumocystis carinii pneumonia has generally been regarded to be an uncommon opportunistic infection in HIV infected individuals in sub-Saharan Africa. The reason for this has not been clear but postulates included a lack of suitable pathogenic types in the African environment, diagnostic difficulties and the more commonly held belief that African HIV infected individuals were dying early from common non-opportunistic pathogens before severe degrees of immunosuppression occured. Recently a trend has emerged at the Mbagathi district hospital whereby an increasing number of HIV infected patients are empirically treated for Pneumocystis carinii pneumonia (PCP) based on clinical and radiological features.

OBJECTIVE

To determine the prevalence of PCP and clinical outcomes of HIV infected patients presenting at the Mbagathi District Hospital, Nairobi with the presumptive diagnosis of PCP.

SETTING

Mbagathi District Hospital, a 169-bed public hospital in Nairobi, Kenya.

METHODS

Patients presenting with a sub-acute onset of cough and dyspnoea were eligible for the study if they were found to have bilateral pulmonary shadows and had negative sputum smears for AFBS. Consenting patients who had no contraindication to fiberoptic bronchoscopy had a clinical evaluation which was followed with a fiberoptic bronchoscopy procedure where bronchoalveolar lavage fluid (BALF) was obtained. BALF was examined for cysts of P. carinii using toluidine blue stain and immunofluorescent antibody test (IFAT). BALF was also processed for fungi, bacteria and mycobacteria using routine procedures. Standard treatment with high dose cotrimoxazole was offered to all patients who were then followed up until discharge from hospital or death whichever came first.

RESULTS

Between June 1999 and August 2000 a total of 63 patients were referred for bronchoscopy. Of these four declined to undergo the fiberoptic bronchoscopy procedure, four died before the procedure could be done, one was judged too sick to undergo the procedure and three had been on cotrimoxazole for longer than five days. Thus 51 patients underwent bronchoscopy. Pneumocystis carinii stain was positive in 19 (37.2%) while death occured in 16 (31.4%) of the 51 patients. There were more deaths in those without PCP but this difference was not statistically significant (odds ratio 0.68 (95% CI 0.35-1.32; P=0.2).

CONCLUSION

PCP was found to be common in HIV infected patients presenting with clinical and radiological features of the disease. The mortality rate for patients with a presumptive diagnosis of PCP is high. This study suggests that cotrimoxazole preventive therapy may be a useful intervention in symptomatic HIV infected patients in Kenya for the prevention of PCP and may avert deaths from this disease.

Validity of random blood glucose as a predictor of the quality of glycaemic control by glycated haemoglobin in out-patient diabetic patients at Kenyatta National Hospital

BACKGROUND

Patients with diabetes mellitus in Kenya come to the hospital for follow-up visits very infrequently. For most of these patients their blood glucose monitoring is done only on the day of visit to the doctor.

OBJECTIVE

To determine how well the physician-based morning random blood level determines or reflects the quality of glycaemic control.

DESIGN

Cross-sectional study (morning, random blood glucose taken between 8.00 a.m. and 12.00 noon).

SETTING

Out-patient diabetic clinic of Kenyatta National Hospital.

SUBJECTS

Patients with diabetes mellitus either type 1 or type 2 attending the out-patient clinic.

MAIN OUTCOME MEASURES

Random blood glucose (morning) and glycated haemoglobin (HbA1c).

RESULTS

The morning random glucose level had a linear relationship with glycated haemoglobin levels taken simultaneously. A blood glucose level of 7 mmol/l had 92.7% sensitivity for good control (HbA1c < or = 7.8%) on a blood sample which was taken simultaneously and 59.8% specific for the same. When blood glucose cut-off level was raised to 10 mmol/l sensitivity fell to 66.3% for HbA1c < or = 7.8%, and 83.2% specificity for poor glycaemic control (HbA1c > 7.8%). There was marked fall in sensitivity of rising random blood glucose level in predicting good glycaemic control in our study, with concomitant rise in specificity of those high cut-off levels of blood glucose in predicting poor glycaemic control.

CONCLUSION

Morning random blood glucose in the ambulatory diabetic patients related well to simultaneously assayed HbA1c. Blood glucose within usual therapeutic targets of 4-8 mmol/l predicted good glycaemic control (HbA1c < or = 7.8%) with high sensitivity at the range of 86.3-98.4%. In resource-poor settings, the morning random blood glucose assay, which is done in patients who may attend the diabetic clinic in the morning hours, may be used to predict the quality of their diabetic control. However caution should be exercised in its widespread use because its overall applicability may be clinic-specific depending largely on the average metabolic control of the diabetic population using that clinic. Further studies need to be done to relate HbA1c to blood glucose levels obtained at different times of the day in this population to determine the best predictor of good glycaemic control.

Tuberculosis re-treatment outcomes within the public service in Nairobi, Kenya

OBJECTIVES

This study was undertaken to describe treatment outcomes in patients started on a re-treatment drug regimen, assess the quality of follow up procedures and the adequacy of the currently advocated re-treatment drug regimen in Nairobi, Kenya.

DESIGN

A retrospective study.

SETTING

Mbagathi District Hospital (MDH), Nairobi, a public hospital that serves as the Tuberculosis (Tb) referral centre for Nairobi.

MATERIALS AND METHODS

The Tb register at the MDH was used to identify patients who were on the re-treatment regimen for Tb. Case records for these patients were then retrieved. From these sources, information on age, sex, HIV status, previous and current tuberculosis disease and drug regimens, adherence to treatment and treatment outcomes, was obtained. Descriptive statistics was used to analyse the data.

RESULTS

Of the total of 4702 patients registered at the MDH between 1996 and 1997, 593 (12.6%) were patients with either recurrent Tb, returning to treatment after default or had failed initial treatment. Of the 593 patients, case records were unavailable for 168 and 17 were children below the age of ten in whom the diagnosis of Tb was uncertain making a total of 185 patients who were excluded from the study. Of the remaining 408 patients, 77 (18.9%) were cured, 61 (15.0%) completed treatment without confirmation of cure, two (0.5%) defaulted, six (1.5%) died and 262 (64.2%) had no outcome information. There were no treatment failures. Treatment success defined as cure or treatment completion was achieved in 94.5% of the 146 patients in whom outcome data were available. HIV positive patients had a statistically significant poorer success rate (34/40, 85%) when compared with HIV negative patients (104/106, 94%), p=0.004. Mycobacterium tuberculosis culture and drug susceptibility testing, was not done.

CONCLUSION

The high number of patients with no treatment outcome information at the MDH is worrying, as these patients may harbour drug resistant bacilli and reflects an inadequate follow up service for Tb re-treatment in Nairobi. However, where treatment outcomes could be assessed, the currently advocated re-treatment regimen achieved a high success rate. These observations point to an urgent need to improve Tb documentation and follow up procedures within the public service in Nairobi in order to forestall the emergence and spread of drug resistant Tb.

Tuberculosis and the HIV epidemic: increasing annual risk of tuberculous infection in Kenya, 1986-1996

OBJECTIVES

The purpose of this study was to assess the impact of the increased incidence of tuberculosis (TB) due to HIV infection on the risk of TB infection in schoolchildren.

METHODS

Tuberculin surveys were carried out in randomly selected primary schools in 12 districts in Kenya during 1986 through 1990 and 1994 through 1996. Districts were grouped according to the year in which TB notification rates started to increase. HIV prevalence in TB patients and changes in TB infection prevalence were compared between districts.

RESULTS

Tuberculous infection prevalence rates increased strongly in districts where TB notification rates had increased before 1994 (odds ratio = 3.1, 95% confidence interval = 2.3, 4.1) but did not increase in districts where notification rates had increased more recently or not at all. HIV prevalence rates in TB patients were 50% in districts with an early increase in notification rates and 28% in the other study districts.

CONCLUSIONS

Countries with an increasing prevalence of HIV infection will need additional resources for TB control, not only for current patients but also for the patients in additional cases arising from the increased risk of TB infection.

Home environment and asthma in Kenyan schoolchildren: a case-control study

BACKGROUND

There is increasing evidence that environmental factors contribute to the development of asthma, so the relationship was studied between home environment factors and asthma among school children of varying socioeconomic backgrounds living in a developing country.

METHODS

A case-control study was performed in participants of a prevalence survey which included 77 schoolchildren with asthma (defined by a history of wheeze, doctor diagnosis, or a decline in FEV1 of > or = 10% at five or 10 minutes after exercise) and 77 age and gender matched controls. Subjects were selected from 402 school children aged 9-11 years attending five primary schools in the city of Nairobi who participated in a prevalence survey of asthma. Visits were made to the homes of cases and controls and visual inspection of the home environment was made using a checklist. A questionnaire regarding supplemental salt intake, parental occupation, cooking fuels, and health of all children in the family was administered by an interviewer.

RESULTS

In multivariate analysis the following factors were associated with asthma: damage caused by dampness in the child's sleeping area (adjusted odds ratio (OR) 4.9; 95% confidence interval (CI) 2.0 to 11.7), air pollution in the home (OR 2.5; 95% CI 2.0 to 6.4), presence of rugs or carpets in child's bedroom (OR 3.6; 95% CI 1.5 to 8.5). Children with asthma reported a supplemental mean daily salt intake of 817 mg compared with 483 mg in controls.

CONCLUSIONS

Home environmental factors appear to be strongly associated with asthma in schoolchildren in a developing nation. These findings suggest a number of hypotheses for further studies.