Is faster always better? The case of same-day diagnosis of tuberculosis

Abstract

Same-day tuberculosis (TB) diagnosis and treatment initiation are increasingly promoted to reduce delays in care and loss to follow-up. Rapid molecular diagnostics have made this feasible, but their implementation among marginalized rural populations presents important challenges. An exclusive focus on speed may compromise diagnostic quality and patient-centred care in settings marked by chronic malnutrition and limited access to healthcare. Chronic malnutrition may impair sputum production, reducing specimen quality and diagnostic sensitivity, while socioeconomic constraints shape care-seeking and continuity of care. Drawing on experience from rural primary healthcare, we argue that diagnostic strategies should balance speed, specimen quality and patient-centred care. Flexible, context-specific approaches, rather than a universal emphasis on same-day diagnosis, are needed to improve TB care among vulnerable populations.

There has been a global push toward same-day tuberculosis (TB) diagnosis and treatment initiation as a way of reducing loss to follow-up. Rapid molecular diagnostics and decentralized testing strategies have made this operationally possible.[1] However, among marginalized populations in remote rural settings, the assumption that faster is always better requires further exploration.[2] For such populations, TB diagnosis and care are biologically, socially, and operationally more complex than rapid diagnostic and care pathways account for.

One overlooked issue is the biology of sample collection. A large proportion of people suffering with TB from marginalized communities are malnourished; many severely so. About one in three adults with TB are unable to produce sputum.[3] Severely malnourished people with TB are likely to be even more “sputum scarce” because of reduced respiratory strength, dehydration, and exhaustion. In practice, this means that in communities with chronic malnutrition, same-day diagnostic models based on “spot sputums” rely on samples that tend to be salivary with low diagnostic sensitivity and risk false-negative results. In our practice (average BMI of patients is ~16kg/m²), <10% of the molecular diagnostic tests were conducted on spot sputums due to the inability of patients to produce the specimens, or due to specimens being rejected due to high salivary content. Our experience suggests that malnourished populations find it especially difficult to produce this specimen. Although there are papers indicating that spot sputums are at least as good as morning sputum samples,[4] no studies have been done in the ability of malnourished populations to produce sputum adequate in quality and quantity for testing. Alternative methods such as induced sputum and gastric aspirates may improve diagnostic yield, but they require more time, higher technical capacity, and stability of vital parameters. They may even be harmful – for example, induction of sputum by saline nebulization can cause hypoxia as well as risk transmission of the disease.

The second aspect is the patient experience. For many rural households, reaching a TB facility requires long journeys, loss of wages, transport costs, and prolonged waiting periods. Within a single visit, patients are expected to navigate consultations, radiographic and laboratory investigations, counseling, and treatment discussions. When TB is diagnosed on the same day, patients must also process the emotional burden of a stigmatized chronic illness while simultaneously committing to terms with months of treatment. For patients who are physically exhausted and psychologically vulnerable, compressing diagnosis, counseling, and treatment initiation into a single encounter may contribute to anxiety and distress. Patient understanding, emotional readiness, and trust strongly shape long-term retention in care. In this context, a brief interval between suspicion, confirmation, and treatment initiation may not represent harmful delay but a necessary space for counseling, family discussion, and treatment preparedness.

Third, same-day diagnoses are also deeply connected to broader health-system realities. Many rural primary healthcare systems continue to operate with staff shortages, weak laboratory infrastructure, inconsistent electricity supply, and high patient loads.[5] Under these conditions, pressure to achieve same-day initiation can shift attention away from other equally important aspects of care, such as nutritional assessment, assessment of co-morbidities, evaluation of drug resistance and counseling. Tuberculosis is a classic primary care condition- it requires all the 5Cs of good primary care, especially continuity of care, coordinated care, and patient-centered care. Rapid initiation may therefore become an administrative achievement rather than a reflection of comprehensive patient-centered care. The challenge is therefore not limited to diagnostic speed, but whether systems possess the capacity to safely absorb and sustain accelerated pathways. Figure 1 highlights some of the complexities of tuberculosis diagnosis in resource-constrained settings, where community mobilization, laboratory testing, and clinical evaluation must be coordinated before treatment initiation.

Figure 1.

The multiple dimensions of tuberculosis care

The prevailing assumption behind the same-day TB diagnosis and initiation of anti-tubercular treatment is that such a process will reduce loss-to-follow-up (LTFU). LTFU is a composite process consisting of loss to follow-up before initiation of treatment and loss to follow-up after start of treatment. Recent studies from India indicate that about 22% of those found to be TB positive become LTFU before treatment initiation. Even among them, about a quarter (27%) died before registration in the TB program.[6] Same-day diagnosis and treatment initiation, therefore, at best, seeks to reduce ~16% of all LTFU. Overall, LTFU in most cases is associated with many systemic and structural factors such as poverty, losing employment, fear of side effects, distance to appropriate health facilities, etc., The solution lies in continuity of care, accountable systems, nutritional recovery, counseling quality, and long-term support, and not merely speed.

Tuberculosis is a biosocial disease[7] rather than an acute diagnostic event. Most patients present only after weeks or months of illness, malnutrition, and social suffering. Within this broader temporal reality, a carefully managed delay of a few days to a week to improve diagnostic quality, stabilize patients, obtain resistance data, and strengthen treatment preparedness should be interpreted as necessary for adequate care.

The current emphasis on same-day diagnosis highlights a larger tension within global health systems between measurable efficiency and contextualized care. As with previous waves of digital health and vertical program implementation, there is a risk that success becomes defined by operational metrics rather than by sustained patient outcomes. For marginalized populations, slowing down may sometimes represent the most clinically sound, equitable, and compassionate pathway toward disease recovery.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.