Implementing TB Intensified Case Finding
Core features of intensified case finding include asking a series of symptom screening questions at every visit, conducting an appropriate diagnostic evaluation for anyone with a positive symptom screen, and performing TB screening for household contacts of all index patients.
Core features of intensified case finding (ICF) include asking a series of symptom screening questions at every visit, conducting an appropriate diagnostic evaluation for anyone with a positive symptom screen, and performing TB screening for household contacts of all index patients.
Questions for adults: Are you experiencing current cough, fever, weight loss, or night sweats?
Questions for children: Is the child experiencing poor weight gain, fever, current cough; and does he or she have contact history with a person who has TB?
TB Symptom Screening at Every Visit
The WHO 2011 Guidelines on ICF and IPT propose that persons living with HIV be screened for TB with a simple clinical algorithm at each and every clinic visit, regardless of the reason for the visit. The guidelines recommend that adults and adolescents who report any one of the symptoms of current cough, fever, weight loss, or night sweats be evaluated further for TB and other diseases. The same guidelines propose that children living with HIV who have any one of the symptoms of poor weight gain, fever, current cough, or contact history with a TB case should be evaluated further for TB and other conditions. (For additional guidance on diagnosis and management of TB in children, see Desk-guide for Diagnosis and management of TB in Children, published by the International Union Against Tuberculosis and Lung Disease and TBCTA, 2010.)
Clinical facilities should put in place procedures to ensure that children and adults living with HIV are screened for TB at each and every visit. An example TB Symptom Screening Questionnaire from Tanzania is provided below. It provides an easy way to document TB screening and monitor implementation.
Diagnostic Evaluation for Persons with a Positive Symptom Screen
In addition to methodical screening of patients at every visit, ICF calls for: (1) well trained microscopists conducting microscopy under optimal laboratory conditions (stocked with appropriate reagents, with microscope properly maintained, and with a workload that allows adequate preparation and inspection of slides); (2) access onsite (or by referral) to high quality radiography, and providers onsite trained in chest X-ray interpretation; (3) where possible, use of liquid culture (or a molecular diagnostic test) as per a nationally endorsed diagnostic algorithm; and (4) strong linkages with home-based care teams or other health monitors in the community to ensure referral of symptomatic patients from the community for further diagnostic testing.
Performing TB Screening for Household Contacts of All Index Patients
Household contact investigation can be performed with assistance of directly observed treatment, short-course (DOTS) workers, community-based health care workers and volunteers, or home-based care teams, utilizing a symptom screen. A tool from the 2009 Caribbean Regional TB Guidelines details the steps involved in contact investigation (Caribbean TB Contact Investigation Questionnaire). Because household contact investigation is a high-yield intervention, overcoming obstacles to its implementation—such as supporting transport of suspect cases identified in the home—should be prioritized in order to ensure that optimal TB case finding can be accomplished.
World Health Organization. Guidelines for intensified tuberculosis case-finding and isoniazid preventive therapy for people living with HIV in resource constrained settings. Geneva: World Health Organization; 2011.
WHO’s most recent guideline advocating inclusion of a symptom screen for HIV-infected adults and another for HIV-infected children that should be routinely performed at every patient encounter and used to determine who requires further studies to rule out active TB.
International Union Against Tuberculosis and Lung Disease. Desk-guide for diagnosis and management of TB in Children. Paris: International Union Against Tuberculosis and Lung Disease (The Union);2010. http://www.tbcta.org/Uploaded_files/Zelf/PaediatricDeskGuideforDiagnosisofTBinChildren1294240195.pdf
This useful decision aid provides guidance on the often very difficult challenge of diagnosing tuberculosis among children.
TB Symptom Screening Questionnaire (adapted from Tanzania)
This screening questionnaire has been adapted from Tanzania's TB Symptom Screening Questionnaire to reflect current (2011) WHO recommendations. Its format makes it very easy to document performance of a TB symptom screen and to track the evaluation conducted in response to a positive symptom screen. For this reason it may prove very useful to other countries that currently find it difficult to abstract TB screening information from medical records.
This document provides a simple, step-by-step description of how to conduct a TB contact investigation.