Huerga H., Varaine F., Okwaro E., Bastard M., Ardizzoni E., Sitienei J., Chakaya J., Bonnet M.
Clinical Research Department, Epicentre, Paris, France; Medical Department, Médecins Sans Frontières, Paris, France; District Hospital Laboratory, Médecins Sans Frontières, Homa Bay, Kenya; Mycobacteriology Unit, Institute of Tropical Medicine, Antwerp, Belgium; Division of Leprosy, Tuberculosis and Lung Disease, Ministry of Health, Nairobi, Kenya; Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya
Huerga, H., Clinical Research Department, Epicentre, Paris, France; Varaine, F., Medical Department, Médecins Sans Frontières, Paris, France; Okwaro, E., District Hospital Laboratory, Médecins Sans Frontières, Homa Bay, Kenya; Bastard, M., Clinical Research Department, Epicentre, Paris, France; Ardizzoni, E., Medical Department, Médecins Sans Frontières, Paris, France, Mycobacteriology Unit, Institute of Tropical Medicine, Antwerp, Belgium; Sitienei, J., Division of Leprosy, Tuberculosis and Lung Disease, Ministry of Health, Nairobi, Kenya; Chakaya, J., Centre for Respiratory Diseases Research, Kenya Medical Research Institute, Nairobi, Kenya; Bonnet, M., Clinical Research Department, Epicentre, Paris, France
Background: The 2007 WHO algorithm for diagnosis of smear-negative pulmonary tuberculosis (PTB) including Mycobacterium tuberculosis (MTB) culture was evaluated in a HIV prevalent area of Kenya. Methods: PTB smear-negative adult suspects were included in a prospective diagnostic study (2009-2011). In addition, program data (2008-2009) were retrospectively analysed. At the first consultation, clinical examination, chest X-ray, and sputum culture (Thin-Layer-Agar and Lowenstein-Jensen) were performed. Patients not started on TB treatment were clinically re-assessed after antibiotic course. The algorithm performance was calculated using culture as reference standard. Results: 380 patients were included prospectively and 406 analyzed retrospectively. Culture was positive for MTB in 17.5% (61/348) and 21.8% (72/330) of cases. Sensitivity of the clinical-radiological algorithm was 55.0% and 31.9% in the prospective study and the program data analysis, respectively. Specificity, positive and negative predictive values were 72.9%, 29.7% and 88.6% in the prospective study and 79.8%, 30.7% and 80.8% in the program data analysis. Performing culture increased the number of confirmed TB patients started on treatment by 43.3% in the prospective study and by 44.4% in the program data analysis. Median time to treatment of confirmed TB patients was 6 days in the prospective study and 27 days in the retrospective study. Inter-reader agreement for X-ray interpretation between the study clinician and a radiologist was low (Kappa coefficient = 0.11, 95%CI: 0.09-0.12). In a multivariate logistic analysis, past TB history, number of symptoms and signs at the clinical exam were independently associated with risk of overtreatment. Conclusion: The clinical-radiological algorithm is suboptimal to diagnose smear-negative PTB. Culture increases significantly the proportion of confirmed TB cases started on treatment. Better access to rapid MTB culture and development of new diagnostic tests is necessary. © 2012 Huerga et al.
amoxicillin; antibiotic agent; cotrimoxazole; erythromycin; ethambutol plus isoniazid plus pyrazinamide plus rifampicin; adult; algorithm; article; bacterium culture; clinical examination; consultation; controlled clinical trial; controlled study; diagnostic test accuracy study; female; human; human cell; Human immunodeficiency virus prevalence; lung tuberculosis; major clinical study; male; medication error; Mycobacterium tuberculosis; nonhuman; patient compliance; prediction; prospective study; receiver operating characteristic; retrospective study; sensitivity and specificity; sputum culture; sputum smear; symptom; thorax radiography; world health organization; Adult; Algorithms; Ambulatory Care; Anti-Bacterial Agents; Female; HIV Infections; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Mycobacterium tuberculosis; Prevalence; Prospective Studies; Retrospective Studies; Sputum; Tomography, X-Ray Computed; Tuberculosis, Pulmonary; World Health Organization; Young Adult; Mycobacterium tuberculosis