Diagnosis of sputum-scarce HIV-associated pulmonary tuberculosis in Lima, Peru

doi:10.1016/S0140-6736(05)17705-8

The Lancet

Volume 365, Issue 9454, 8–14 January 2005, Pages 150-152

https://doi.org/10.1016/S0140-6736(05)17705-8 Get rights and content

Summary

Sputum induction, bronchoalveolar lavage, or gastric aspiration are often needed to produce adequate diagnostic respiratory samples from people with HIV in whom tuberculosis is suspected. Since these procedures are rarely appropriate in less-developed countries, we compared the performances of a simple string test and the gold-standard sputum induction. 160 HIV-positive adults under investigation for tuberculosis, and 52 asymptomatic HIV-positive control patients underwent the string test followed by sputum induction. The string test detected tuberculosis in 14 patients in whom this disease was suspected; sputum induction detected only eight of them (McNemar's test, p=0·03). These preliminary data suggest that the string test is safe and effective for retrieval of useful clinical specimens for diagnosis of pulmonary tuberculosis, and is at least as sensitive as sputum induction.

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Cited by (58)

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Citation Excerpt :
The best specimen for diagnosis of pulmonary TB in a child with nonproductive cough is an early morning gastric aspirate obtained before ambulation or feeding; 3 gastric aspirates on 3 consecutive mornings are required. There are innovative ways of obtaining swallowed respiratory samples for TB diagnosis in children who cannot produce sputum, such as induction of sputum with aerosolized hypertonic saline58 and the string test.60,61 Nucleic acid amplification tests for the detection of mycobacterial DNA or RNA are in clinical use.
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2015, International Journal of Infectious Diseases
The Xpert MTB/RIF (MTB/RIF) test has advanced the field of tuberculosis (TB) diagnostics; however, depending on age and HIV status, 10–85% of individuals with presumed pulmonary TB (PTB) are unable to produce sputum.
The feasibility of using MTB/RIF and culture on stool and string test specimens from 13 adult patients with presumed PTB was studied.
The string test was well tolerated with a median Wong Baker Faces score of 2. The string test had 100% sensitivity and specificity by MTB/RIF and 87.5% sensitivity and 100% specificity by culture. In stool, Mycobacterium tuberculosis DNA was detected in all cases of culture-confirmed PTB.
The string test and stool provide diagnostic specimens that warrant further investigation.
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2011, Paediatric Respiratory Reviews
Citation Excerpt :
After 4 hours the string was withdrawn and used for mycobacterial culture. The culture yield from string test samples (9%) was better than that from IS (5%) in this adult population.13 The test was subsequently proposed for use in children and shown to be well tolerated by older children (median age 8 years).14
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In areas where it is endemic, tuberculosis remains a major, often unrecognized cause of disease and death among children. Symptoms are often subtle, and sputum smears have limited utility. This review summarizes the principles of diagnosis, treatment, and prevention.
Widespread implementation of the strategy of directly observed treatment short course (DOTS) during the 1990s resulted in improved global control of tuberculosis.¹ However, its effectiveness has been limited in areas where poverty and infection with the human immunodeficiency virus (HIV) or drug-resistant tuberculosis are prevalent, and the emphasis on a positive sputum smear as the diagnostic criterion actually excludes most children from care.² Tuberculosis remains a major but often unrecognized cause of disease and death among children in areas where the disease is endemic³; service delivery in such areas is hampered by the absence of pragmatic strategies to guide . . .
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Research LettersDiagnosis of sputum-scarce HIV-associated pulmonary tuberculosis in Lima, Peru

Summary

Lancet

A new technique for sampling duodenal contents: demostration of upper small-bowel pathogens

Am J Trop Med Hyg

Research Letters
Diagnosis of sputum-scarce HIV-associated pulmonary tuberculosis in Lima, Peru