Evaluation of two novel Ziehl-Neelsen methods for tuberculosis diagnosis.

BACKGROUND: Currently, the diagnosis of tuberculosis (TB) in Ghana relies on direct sputum smear, Ziehl- Neelsen (ZN) staining method. This method has low sensitivity and poses some health risks. The study was to compare the, direct sputum smear, (ZN) staining method against two newer ZN methods; 1% Sodium hypochlorite (NaOCL)-xylene floatation and 1% NaOCL sedimentation methods, to determine the most sensitive and the safest STUDY DESIGN: A prospective descriptive study involving 150 adult patients attending Komfo Anokye Teaching Hospital, Kumasi, Ghana suspected of pulmonary tuberculosis, using the three ZN microscopy methods: direct sputum smear, 1% NaOCL sedimentation, and 1% NaOCL-xylene floatation, for the detection of acid fast bacilli (AFB). Sputum culture on Lowenstein-Jensen (LJ) slopes was used as the gold standard for determining the sensitivity and specificity rates. RESULTS: The sensitivity rates of NaOCL sedimentation, NaOCL-xylene floatation and direct smear methods were 77.2%, 71.8% and 66.3% respectively. The specificity rate was 95.9 % for all three methods. Whereas the difference between the NaOCL sedimentation and the direct smear methods was statistically significant (P= 0.0446), that between the NaOCL-xylene floatation and direct smear was not (P=0.1788). CONCLUSION: In spite of the cost of chemicals, the hypochlorite sedimentation method was found to be the most accurate and the safest.

Prevalence of pathogenic Escherichia coli and parasites in infants with diarrhoea in Kumasi, Ghana.

OBJECTIVES: To determine the relative frequencies and prevalence rates of pathogenic Escherichia coli and intestinal parasites in hospitalised infants (0-5 years) in Kumasi. DESIGN: A prospective descriptive study of screening 162 (83 males and 79 females) infants with diarrhoea and 122(64 males and 58 females) non-diarrhoeal infants controls for pathogens (E. coli and intestinal parasites) by standard microbiological methods. SETTING: Komfo Anokye Teaching Hospital and Maternal and Child Hospital, Kumasi, Ghana. RESULTS: From the 162 in the diarrhoeal group 96(59.6%) pathogens, and from the 122 in the control group, eight (6.6%) pathogens were isolated. Enteropathogenic E. coli (EPEC) was the most frequently detected pathogen, accounting for 24(14.8%) of the findings in the diarrhoeal group, five (4.1%) in the non-diarrhoeal control group. Of the 26 EPEC isolates, there were nine serotypes with the three dominant ones being 0125 (6), 0119 (5), and 026 (15). Other agents isolated included Ascaris lumbricoides 18(11.1%) and two (1.6%), Cryptosporidium 13(8.0%) and one (0.8%) for diarrhoeal and non-diarrhoeal infants respectively. The following were detected only in diarrhoeal stools. Giardia lamblia, six (3.7%); Trichomonas hominis, three (1.9%); Trichuris trichiura one (0.6%) and hookworm, one (0.6%). CONCLUSION: From this study, EPEC and Cryptosporidium may be considered as important diarrhoeagenic pathogens and it is hoped that provision of potable water and good sanitation may decrease diarrhoeas in infants caused by these agents.

Salmonellae carrier status of food vendors in Kumasi, Ghana.

OBJECTIVE: To determine the prevalence of chronic typhoidal salmonellae amongst food vendors in Kumasi Ghana. DESIGN: A prospective study. SETTING: Sitting and itinerant food vendors in Kumasi. METHODS: Screening of 258 (230 females of 28 males) healthy food vendors for Salmonella typhi, and S. paratyphi A, B, and C, using stool culture, the widal test, and standard microbiological identification methods. MAIN OUTCOME MEASURES: Prevalence of chronic typhoidal Salmonellae carriers among food vendors in Kumasi. RESULTS: Typhoidal Salmonellae were isolated from six people, giving a carriage rate of 2.3%. Three of the Salmonellae isolated were S. typhi, and they had significant Widal agglutinin titres of > or = 1/160 and > or = 1/320 for 0 and H antigens, respectively. The other three were non-typhoidal Salmonellae. The three had S. typhi and the other three had titres of 1/80 or less for both 0 and H antigens, respectively. We have discussed the implications of this high carriage rate, and we have suggested the inclusion of screening for Salmonellae of the regular health screening exercise undertaken by food handlers to detect and monitor chronic carriers in the food industry, to help control salmonella diseases in the community. CONCLUSION: From our study, food handlers consitute a significant risk in the spread of enteric fever in Kumasi. We therefore, suggest the inclusion of screening for Salmonellae in the regular obligatory six-monthly examination required of food handlers and to monitor those found to be infected.

Pulmonary tuberculosis in Kumasi, Ghana: presentation, drug resistance, molecular epidemiology and outcome of treatment.

To assist implementation of tuberculosis (TB) control measures, knowledge of the disease characteristics in a community is essential. This study in Kumasi, Ghana, correlates the clinical presentation, microbiology, molecular epidemiology and clinical outcome of thirty consecutively diagnosed patients with new smear-positive pulmonary TB. Several important factors that potentially promote disease transmission in the community were identified: patients had prolonged duration of productive cough prior to diagnosis (mean=4.1 months; SD=2.1); the disease was typically advanced at presentation and Ziehl-Neelson sputum smears indicated a high bacterial load (80% graded > AFB++); home accommodation was overcrowded with a mean of 3.3 other persons sleeping in the same room as the patients at night. IS6110 restriction fragment length polymorphism (RFLP) fingerprinting of 25 isolated (23 Mycobacterium tuberculosis and 2 Mycobacterium africanum) from epidemiologically unrelated cases identified 3 identical strains and 3 clusters containing 2, 4 and 8 isolates of > or =80% similarity, suggesting high rates of disease transmission. A high prevalence of primary resistance to isoniazid was found (6 out 26; 23%) but resistance to rifampicin, pyrazinamide, ethambutol, streptomycin and ciprofloxacin was not detected. Smear coversion at 2 months and final outcome of treatment with short courses chemotherapy were independent of isoniazid resistance, but the rate of treatment default was unacceptably high (37%). High rates of disease transmission, primary isoniazid resistance and treatment default all indicate poor TB control. The use of rifampicin-containing short-course chemotherapy in this community must be accompanied by adequate resources and infrastructure to ensure very stringent treatment supervision to improve case-holding and reduce the risk of multi-drug resistance.

Determination of diagnostic Widal titres in Kumasi, Ghana.

Three hundred and seven healthy food handlers and 34 blood-culture positive enteric fever patients were screened for Salmonellae agglutinins using the Widal test. Of the 307 healthy food handlers, only 3 (1.0%) had an anti-O titre of > or = 1/160 and 8 (2.6%) an anti-H titre of > or = 1/320 for Salmonella typhi, but the majority, 214 (69.7%) and 149 (48.5%) had titres of < 1/20 for O and H agglutinins respectively. Similar agglutinin titres were also seen for S. Paratyphi A, B, and C. In the 34 enteric fever patients, for S typhi, based on anti-O titre of > or = 1/160, 25 persons showed a significant titre, a sensitivity of 73.5%, and a specificity of 99.0%. And 21 persons showed a significant titre of > or = 1/320 for anti-H, a sensitivity of 61.8% and a specificity of 97.4%. Based on these findings, titres of > or = 1/160 and > or = 1/320 for anti-0 and anti-H respectively, were considered diagnostic for enteric fever in Kumasi, Ghana.

Life-threatening cutaneous reactions to thiacetazone-containing antituberculosis treatment in Kumasi, Ghana.

Antituberculosis treatment containing thiacetazone is associated with a high incidence of life-threatening cutaneous drug reactions in patients infected with the human immunodeficiency virus (HIV). In order to develop a local policy concerning the use of this drug, a study was undertaken to determine the incidence of such reactions in a total of 1063 Ghanaian adult patients treated for pulmonary tuberculosis (PTB) with thiacetazone-containing regimens. The incidence was retrospectively determined in 3 different treatment groups, comparing: (A) unselected use of thiacetazone; (B) exclusion of thiacetazone from all patients with positive HIV serology; (C) selective exclusion of thiacetazone from patients with clinical criteria suggesting HIV infection plus education of health workers and patients. Of the 408 patients in group A receiving thiacetazone, 9 (2.2%) developed life-threatening cutaneous reactions and 7 of these were HIV-positive. Overall, 6.8% of HIV-positive patients compared to 0.65% of HIV-negative patients developed severe reactions (P < 0.01; relative risk = 10.5). Six of the 9 patients with reactions died. All 379 patients in group B were screened for HIV antibodies and positive cases (23%) received a regimen in which thiacetazone was substituted by ethambutol. In contrast to Group A, only one HIV-negative patient (0.26%) developed a severe cutaneous reaction (P = 0.02). Among 276 patients in group C, thiacetazone was substituted with ethambutol only in those with clinical evidence of HIV infection (8%) and staff and patients were educated about early recognition of the side-effect. With this policy, these were no admissions with severe cutaneous reactions compared to 2.2% of those in group A (P = 0.01). In conclusion, a policy of selective use of thiacetazone in the treatment of PTB based on clinical criteria combined with patient and staff education was found to be a practical and cost-effective strategy combating severe cutaneous reactions to thiacetazone.

Study of the aetiologic agents of meningitis in Kumasi, Ghana, with special reference to Cryptococcal neoformans.

OBJECTIVE: To evaluate the importance of Cryptococcus neoformans, an opportunistic in meningitis, in healthy and HIV infected patients in Kumasi, Ghana. DESIGN: A prospective study; isolating the aetiologic agents of meningitis from cerebrospinal fluid (CSF) using standard methods. SETTING: Kumasi city, Ashanti region of central Ghana. SUBJECTS: One thousand five hundred and seventy patients suspected of meningitis, including 28 HIV infected and AIDS patients. MAIN OUTCOME MEASURE: The pattern and distribution of the main etiologic agents of meningitis in Kumasi, Ghana shown. RESULTS: Of the 1570 CSF samples examined, 1256 (80%) showed no abnormality. Of the 314 (20%) with abnormalities, 147 were bacterial, and 167 diagnosed aseptic. No cryptococcal cells were found. CONCLUSION: There is a paucity of cryptococcal meningitis in Kumasi, Ghana, and it is not recommended to screen routinely for the fungus in meningitis investigations.

Evaluation of a commercial immunodiagnostic kit incorporating lipoarabinomannan in the serodiagnosis of pulmonary tuberculosis in Ghana.

UNLABELLED: We evaluated 'Mycodot', a commercially marketed immunodiagnostic test for tuberculosis which detects antibodies to lipoarabinomannan antigen. Serum was tested from 52 patients with newly diagnosed smear-positive pulmonary tuberculosis, of whom 20 were HIV-positive and 32 HIV-negative. Control sera were taken from 40 patients of whom 20 had acute non-tuberculous lobar pneumonia and 20 patients had no respiratory disease. The test was found to have a very high specificity of 97.5% (95% CI:92.5-100%). However, the sensitivity in HIV-negative patients was 56% (95% CI:39-73%), and was substantially lower at 25% (95% CI:6-44%) in HIV-positive patients. IN CONCLUSION: 'Mycodot' was found to be a highly specific and easily performed assay. However, the poor sensitivity, especially in HIV-infected patients, renders it unlikely to be useful either as a primary or adjunctive diagnostic test for tuberculosis, particularly in countries with a high prevalence of HIV. A larger trial of this assay in Ghana was not deemed necessary.

Epidemiology of Buruli ulcer in Amansie West district, Ghana.

This paper describes 90 cases of Buruli ulcer in Amansie West district, Ghana. 49% were below 15 years of age while 20% were over 50 years. There was a significant difference in the age and sex composition, with more males among the younger age groups than females but the converse among adults. Seasonal variation is described, with peak incidence in September and October. Cases who had received bacillus Calmette-Guérin (BCG) vaccination had a shorter duration of the ulcer than those who were not vaccinated. No such association was found between BCG vaccination and the age of onset of the disease. There was no significant difference between cases and controls regarding their BCG vaccination status. There is an urgent need to regard Buruli ulcer in Ghana more seriously.