Effectiveness of a structured gastric aspirate training on diagnosis of paediatric tuberculosis among healthcare workers in rural Chhattisgarh

Abstract

Background and objectives

Childhood tuberculosis remains underdiagnosed in India. Although gastric aspiration is recommended to improve microbiological confirmation, its use at lower-tier health facilities is limited by training, infrastructural, and logistical constraints. This study evaluated whether a structured, training-focused implementation strategy could integrate gastric aspiration into routine paediatric TB diagnostic workflows at primary and community health settings, and assessed its feasibility, acceptance, uptake, and diagnostic yield.

Methods

We conducted a mixed-methods controlled before-and-after implementation study in Rajnandgaon district, Chhattisgarh, involving training of healthcare providers across 39 primary health centres and 10 community health centres. The intervention included hands-on training, procedural standardisation, mentorship, limited logistical support and community engagement, guided by the consolidated framework for implementation research. Outcomes assessed included procedural uptake, caregiver acceptance, diagnostic yield, and contextual factors influencing implementation.

Results

Of 652 eligible children with presumptive TB, 567 (87%) underwent gastric aspiration, versus 18 pre-intervention, indicating a marked increase in uptake. Most samples (75%) were collected at peripheral facilities, reflecting decentralisation of the procedure. However, microbiological confirmation was low, with a cartridge based nucleic acid amplification test (CBNAAT) positivity rate of 0.9%. Quality audits identified persistent operational challenges, including suboptimal cold-chain maintenance, delayed specimen transport, inadequate sample volume, and variable staff sensitisation, which likely contributed to the low diagnostic yield.

Interpretation and conclusions

A structured training and implementation approach enabled integration of gastric aspiration into routine practice at peripheral health facilities with high uptake and acceptance. However, low microbiological yield highlights substantial pre-analytical and system-level constraints that limited diagnostic effectiveness.

Childhood tuberculosis (TB) is a significant yet under-recognised public health challenge, with India bearing approximately 31% of the global paediatric TB burden. Despite its high prevalence, children represent only 6–7% of patients treated under the National Tuberculosis Elimination Programme (NTEP), indicating an estimated detection gap of nearly 56%.¹ Several factors contribute to this gap, including non-specific clinical presentation, paucibacillary disease, a high proportion of smear-negative and extrapulmonary TB and limited diagnostic infrastructure, particularly in resource-constrained settings.^2,3 Microbiological confirmation is essential to ensure timely therapy and is the only reliable way to detect rifampicin resistance, which has a reported prevalence of 3% among Indian children.⁴ Because children under 10 y are generally unable to expectorate, gastric aspiration is utilised to retrieve swallowed respiratory secretions that pool overnight. Gastric aspiration is endorsed by the World Health Organization (WHO) and the NTEP, with Indian studies reporting cartridge based nucleic acid amplification test (CBNAAT) based positivity rates ranging from approximately 10 to 21% in children with presumptive pulmonary tuberculosis.^5–9

Despite the proven diagnostic utility of gastric aspiration, its use remains largely restricted to tertiary care centres due to perceived procedural complexity, inadequate training of healthcare workers and logistical constraints at primary and secondary care levels.^10-12 Implementation is further hindered by the paucibacillary nature of paediatric TB, which limits mycobacterial culture yield to only 30–40% even under ideal conditions. In routine programmatic settings, effectiveness is often attenuated by pre-analytical operational challenges, including inadequate specimen volume, suboptimal cold-chain maintenance, and transport delays. In States such as Chhattisgarh, approximately 20% of the population is tribal and 31.3% of under-five children are underweight, reflecting substantial structural and nutritional vulnerability. These challenges are mirrored in TB programme performance, with only about 55% of expected smear-positive cases detected, contact-tracing audits reporting an 8.7% TB yield among child contacts, and marked under-ascertainment of presumptive cough cases (20,000 notified vs an expected 60,000 per NTEP norms), leading to frequent refusal or re-referral of child contacts at peripheral facilities.^13,14 Crucially, the primary barrier to decentralised diagnosis is not the procedure itself, but the lack of trained personnel, system sensitisation, and standardised implementation frameworks at the facilities where missed cases first present.⁴ Prior programmatic efforts to strengthen paediatric TB diagnosis in India have largely focused on expanding molecular testing and contact investigation, with limited emphasis on integrating specimen collection workflows into routine practice at peripheral facilities.^13,15,16 Community-based strategies and provider sensitisation have improved adult TB case detection, but evidence on their effectiveness in decentralising paediatric diagnostic procedures remains sparse.^17,18

Against this backdrop, we designed to assess the feasibility and effectiveness of a structured, training-focused implementation strategy to integrate gastric aspiration into routine paediatric TB diagnosis workflows at lower-tier facilities. Using the consolidated framework for implementation research (CFIR), the project aimed to assess whether targeted capacity building—including hands-on training, procedural standardisation, and community engagement through the Mitanin network—could successfully decentralise diagnostic services. The primary objectives were to measure the impact of this strategy on procedural uptake and parental acceptance across the health care facilities in Rajnandgaon district, and to evaluate the resulting microbiological yield and case detection rates in a resource-limited rural setting.

Methods

This study was initiated jointly by the department of Pediatrics, All India Institute of Medical Sciences, Raipur; department of Pediatrics, Government Medical College, Rajnandgaon; department of Community Medicine, Pt. Jawaharlal Nehru Memorial Medical College, Raipur; and the State Health Resource Centre, Government of Chhattisgarh. Ethical approval was obtained from the institutional ethics committee, and permissions were secured from the Directorate of Health Services before initiating the intervention. Written informed consent was obtained from parents or guardians after explaining the procedures in the local language. Data confidentiality and patient anonymity were maintained, with data shared only with authorised administrators responsible for programme implementation when necessary.

Study setting

Rajnandgaon, a predominantly rural district in Chhattisgarh with over 1.5 million residents, has a significant tribal and socio-economically disadvantaged population. Healthcare infrastructure includes one district hospital and a government medical college, 10 community health centres (CHCs) serving 120,000–150,000 people each, 51 primary health centres (PHCs) serving ∼30,000 each and 332 sub-health centres (SHCs) serving ∼4,000 residents each. Many facilities face shortages of full-time doctors, staff housing, basic amenities, and essential infrastructure such as water, sanitation, laboratories, or electricity, with some SHCs operating from temporary premises. Despite an established public health network, infrastructural deficiencies at all levels made Rajnandgaon suitable for piloting improved paediatric TB diagnostics, focusing on strengthening CHCs and PHCs. Key stakeholders included paediatricians, general physicians, nurses, lab technicians, frontline health workers (Mitanins), district TB officers, and programme managers. Mitanins, trusted community health workers, identified presumptive paediatric TB cases through household symptom screening and contact tracing, especially among vulnerable groups like severely malnourished children, facilitated early referral for diagnostic testing including gastric aspiration and counselled parents to ensure procedure acceptance. Written informed consent was obtained in the local language. Although patients were not involved in study design, community engagement was critical to implementation success.

Study design

We conducted a mixed-methods implementation study using a controlled before-and-after design to evaluate the impact of a structured training and advocacy intervention on gastric aspiration adoption in Rajnandgaon, Chhattisgarh, India. Children aged 0 to 10 y with presumptive TB were included, excluding those on antitubercular therapy for more than 2 d or who had recently defaulted. The 14-mo study (October 2016–November 2017) covered orientation, permissions, training and implementation. Stakeholders were integral: medical college faculty led training, the State Health Resource Centre (SHRC) provided technical support, RNTCP managed logistics, and the Directorate of Health Services guided policy. Healthcare workers performed gastric aspiration, district staff handled diagnostics, and Mitanins, community mobilisers and parents facilitated participation. As a pilot, no formal sample size was required, but estimates suggested 1,500 presumptive cases from 150,000 paediatric out-patient department (OPD) attendees annually across 50 facilities. After eligibility (80%) and adherence (85%), 1,000 gastric aspirates were expected, with 300 projected smear-positive. Reporting followed standards for reporting implementation studies (StaRI) guidelines, emphasising both the implementation process and diagnostic effectiveness in the paediatric population.

Diagnostic workflow and implementation protocol

Figure 1 Implementation began with a 2-d hands-on gastric aspiration training at the medical college led by paediatric faculty for one doctor and one nurse from 39 PHCs, 10 CHCs, and 2 district hospitals. Provider competency was confirmed at the district hospital through standardised demonstrations and skills checklists prior to independent practice. Trained personnel initiated gastric aspiration from November 2016, with samples referred to the district CBNAAT laboratory.

Fig. 1.

Diagnostic algorithm for presumptive paediatric tuberculosis at outpatient facilities. Symptom-based screening identifies presumptive TB, followed by microbiological confirmation (gastric aspirate microscopy and CBNAAT); negative results trigger evaluation for alternative diagnoses. (Source: Figure was created using Microsoft PowerPoint. No AI-based image generation tools were used).

Community health workers identified presumptive paediatric TB cases: children with a family contact in the past 6 mo—screening for (i) fever/cough ≥2 wk, (ii) weight loss or severe acute malnutrition, or (iii) positive contact history. Symptomatic children were assessed by assistant medical officers (AMO) and PHC (MO), and pulmonary presumptive cases underwent gastric aspiration on designated field days. Children were admitted a day in advance; early-morning fasting aspirates were collected on two consecutive days, cold-stored, and transported within 2–4 h for CBNAAT and drug susceptibility testing. Samples delayed beyond one hour were neutralised with 100 mg sodium carbonate, maintained in cool packs, and transported the following day.

Quantitative data were extracted from OPD and laboratory registers, Nikshay, CBNAAT records, and facility-level clinical, radiological, Mantoux and gastric aspirate results (November 2016–November 2017). Qualitative and socio-demographic data were collected by mobilisers across four blocks from October 2017, supplemented by district TB office records. Determinants of implementation were examined through in-depth caregiver interviews and focus group discussions with MOSs and nurses, which were audio-recorded, transcribed, and thematically analysed.

Implementation fidelity was assessed through routine supervisory visits by project staff and district TB officers, incorporating direct observation, register review and structured feedback. SOP adherence—including specimen adequacy, cold-chain maintenance (4–8°C), and transport timelines—was documented in facility registers. Six quality audits conducted between October 2016 and November 2017 evaluated procedural proxies rather than diagnostic yield, identifying 9–22 specimen rejections per audit, improvement in cold-chain compliance from 30% to over 50%, and persistently low timely transport rates, peaking at 36%. Findings informed on-site mentorship and corrective actions.

Operational definitions

• Feasibility: The ability to perform gastric aspiration within existing healthcare workflows with trained staff and available infrastructure.

• Acceptance: The proportion of parents consenting to the gastric aspiration procedure for their child.

• Uptake: The proportion of eligible children (presumptive TB cases not able to expectorate sputum) from whom samples were actually collected.

• Diagnostic yield: The proportion of collected samples testing positive for TB by CBNAAT.

Statistical analysis

Data were entered into Microsoft Excel and scrutinised for completeness and consistency. Descriptive statistics summarised implementation outcomes (acceptance, adherence and feasibility). TB case detection rates and gastric aspirate positivity rates were analysed using proportions and frequency distributions.

Results

During the intervention period, 1,08,988 children under 10 y of age attended outpatient services, of whom 652 (0.6%) were identified as presumptive paediatric TB cases and referred for evaluation. Presumptive cases were evenly distributed by sex, with SAM being the most common trigger for screening. Mantoux testing was performed in 397 children, yielding a positivity rate of 26.9%, supporting a high underlying burden of TB infection among those screened. Primary Health Centers (PHCs) documented the highest proportion of presumptive paediatric TB cases relative to outpatient volume (approximately 4%), underscoring their central role in case identification.

Of the 652 children called for testing, 567 underwent gastric aspiration, corresponding to an overall parental acceptance rate of 87% across all levels of care ( Table I), exceeding the predefined programmatic target of 85%. Diagnostic uptake increased markedly following the intervention, from only 18 CBNAAT requisitions in the six months preceding implementation (April–October 2016) to 567 during the project period. Decentralisation was substantial, with 75% (426/567) of samples originating from PHCs and CHCs. Figure 2 demonstrates a sustained increase in specimen collection rates from 65% to over 90% over time, indicating progressive normalisation of the procedure within routine services.

Table I.

Uptake and acceptance of gastric aspiration for presumptive pediatric tuberculosis across healthcare facility levels

	Primary health centre	Community health centre	District hospital, medical college	Total
Number of facilities	39	10	2	51
All OPD patients in 0-10 y age group	8347	36462	64179	108988
Number of gastric aspirate specimens collected	298	128	141	567
Number of patients who were eligible for gastric aspiration (Presumptive paediatric TB patients)	343	147	162	652
Percentage of gastric aspiration	86.9	87.1	87	86.9

Distribution of eligible children, gastric aspirate specimens collected and procedure acceptance rates across primary health centres, community health centres, and district/tertiary facilities

Fig. 2.

Determinants of acceptance and diagnostic yield of gastric aspiration in children. Health-system, provider and caregiver-level facilitators and barriers influencing procedure uptake and diagnostic yield. (Source: Figure formatting and design were done using Microsoft PowerPoint).

Despite high uptake, microbiological confirmation remained low. The CBNAAT positivity rate was <1% (0.9%), substantially lower than the anticipated yield of approximately 30% and below expected population prevalence. Among paediatric TB notifications in Rajnandgaon district, 71 cases were reported in 2016 and 54 in 2017, fewer than half of whom presented with pulmonary symptoms; only five cases were microbiologically confirmed by CBNAAT, including one diagnosed prior to project initiation. Compared with programmatic estimates, 73% of expected children attended outpatient services, and only 65% were eligible for gastric aspiration versus an anticipated 80%. Nevertheless, procedure acceptance remained consistently high at 87% (567/652), both overall and across facility hierarchies. No procedure-related adverse events or unintended effects were recorded.

Implementation challenges, confounders and improvement strategies

Implementation was influenced by multiple system-level and contextual constraints. Training of doctors and nurses (November 2016–July 2017) was repeatedly rescheduled due to competing clinical responsibilities, while intensive line-listing of presumptive TB cases (January–May 2017) overwhelmed frontline staff and delayed sample collection. Infrastructure and logistical limitations between January and June 2017—including staffing shortages at PHCs, absence of courier mechanisms, unpaid travel allowances, and initial administrative reluctance to accept gastric aspirates—further impeded implementation, although advocacy meetings ultimately resolved specimen acceptance barriers ( Fig. 3). Continued reliance on informal healthcare providers in remote areas delayed care-seeking, while resistance from district RNTCP staff, who questioned the feasibility of gastric aspiration at peripheral facilities and anticipated community resistance, necessitated sustained State-level and institutional advocacy.

Fig. 3.

Audit-wise trends in presumptive pediatric TB identification and gastric aspirate collection. Temporal comparison of presumptive TB cases and gastric aspirate specimens collected across audit cycles.

Implementation fidelity was systematically assessed through six sequential quality audits conducted between October 2016 and November 2017, focusing on pre-analytical process indicators rather than diagnostic yield ( Table II). More than 50% of facilities initially lacked functional refrigerators, resulting in frequent cold-chain deviations; although storage adherence improved from 30% to over 50% by programme end, gaps persisted. Timely transport remained suboptimal, with only 29–36% of specimens reaching the CBNAAT laboratory within the recommended 4-h window across audits (improving from 22/59 in Audit 1 to 41/113 in Audit 6). Specimen rejection due to inadequate volume (<5 mL) was frequent, ranging from 9 to 22 samples per audit. These persistent pre-analytical deficiencies plausibly explain the low microbiological yield (0.9%), necessitating empirical treatment initiation for a majority of the notified TB cases.

Table II.

Quality audit indicators for pre-analytical processes in gastric aspirate specimen handling

Audit serial number	Storage unit temperature optimum (4o-8oC)	Specimen rejected due to inadequate quantity (total specimen collected)	Specimen transported within 4 h of collection (total specimen collected)
Audit 1 (12/12/2016)	13/45 (29%)	22 (59)	13 (59)
Audit 2 13/02/2017)	16/39 (41%)	18 (71)	26 (71)
Audit 3 (10/04/2017)	22/49 (45%)	20 (93)	12 (93)
Audit 4 (12/06/2017)	28/50 (56%)	12 (111)	18 (111)
Audit 5 (21/08/2017)	30/59 (51%)	9 (120)	34 (120)
Audit 6 (16/10/2017)	31/58 (53%)	11 (113)	41 (113)

Audit-wise assessment of cold-chain maintenance, specimen rejection due to inadequate volume, and timely transport of gastric aspirate samples to the CBNAAT laboratory

Corrective strategies included routine supervisory visits with direct observation, register review and structured feedback; on-site mentorship; selective refrigerator repairs and replacement; reinforcement of cold-chain practices using audio-visual aids; and practical demonstrations to standardise specimen volume. Engagement of trained community mobilisers through the Mitanin network from October 2017 improved data completeness and facilitated an 87% procedure acceptance rate, although performance fluctuated in the absence of refresher training and consistent incentive distribution. Qualitative analysis identified caregiver anxiety related to fasting and tube discomfort, economic barriers such as transport costs and work disruption, and social stigma leading to false addresses or relocation as additional constraints affecting access and follow up.

Discussion

This study evaluated the feasibility of integrating gastric aspiration into routine paediatric TB diagnostic workflows at primary and community health facilities in a resource-limited setting. The intervention helped increase procedural uptake and was associated with high caregiver acceptance across facility levels, indicating that decentralisation of gastric aspiration may be operationally feasible outside tertiary centres. However, microbiological confirmation remained low, highlighting important limitations in translating procedural adoption into diagnostic effectiveness within routine public health settings.

Evidence from prior operational studies suggests that decentralising childhood TB diagnostic services to primary and district levels can improve access to testing and in some settings, increase case detection.^4,19 WHO guidelines similarly recommend decentralised paediatric TB diagnosis closer to communities, while acknowledging low certainty of evidence and significant implementation challenges. The findings of the present study are broadly aligned with this literature in demonstrating feasibility and acceptability of decentralised service delivery, but they also underscore the difficulty of achieving meaningful microbiological yield in routine programmatic conditions without concurrent investments in health-system capacity.

Despite high uptake of gastric aspiration, CBNAAT positivity was unexpectedly low. This finding is consistent with reports from early decentralisation studies, including TB-Speed, which observed that increased availability and uptake of specimen collection methods did not necessarily translate into higher diagnostic yield.⁴ In our setting, persistent pre-analytical and system-level constraints—such as inadequate specimen volume, suboptimal cold-chain maintenance, and delays in transport—likely contributed to attenuation of diagnostic effectiveness. These results suggest that training and procedural decentralisation alone are insufficient to overcome structural barriers affecting paediatric TB diagnosis under programme conditions.

The primary strength of this study lies in its pragmatic implementation within routine public health facilities, particularly at peripheral levels where paediatric TB diagnostic capacity is limited. The study also systematically documented operational constraints through quality audits, providing insight into specific system gaps that influenced outcomes. No procedure-related adverse events were observed, supporting the safety of gastric aspiration when performed by trained staff at lower-tier facilities. Nevertheless, the low microbiological yield limited assessment of diagnostic effectiveness, the absence of a control group precluded causal inference, and clinical outcomes or treatment delays were not evaluated.

Several limitations should be acknowledged. The low microbiological yield limited assessment of diagnostic effectiveness and constrained interpretation of impact on case detection. The absence of a control group precludes causal attribution and the study did not assess clinical outcomes or treatment delays. Importantly, the findings reflect real-world implementation under routine conditions and should not be interpreted as failure of decentralisation, but rather as evidence of the substantial system strengthening required to support effective paediatric TB diagnostics.

In summary, decentralisation of gastric aspiration to peripheral health facilities was feasible and acceptable but did not result in improved microbiological confirmation. Community engagement through frontline health workers facilitated identification and referral of high-risk children, particularly those with severe acute malnutrition. However, similar to experiences from community-based and active case-finding initiatives under India’s NTEP, gains at the level of screening and referral were not matched by improvements across the full diagnostic cascade.¹⁵ From a programme and policy perspective, these findings suggest that scale-up of gastric aspiration within national TB programmes should be accompanied by strengthened specimen handling, transport logistics, and quality assurance mechanisms, without which gains in access may not translate into improvements in bacteriological confirmation or programmatic yield.

शोध-संदेश

बच्चों में क्षय रोग (टी बी) की समय पर पहचान बेहतर बनाने के लिए छत्तीसगढ़ के ग्रामीण स्वास्थ्य केंद्रों में स्वास्थ्यकर्मियों को गैस्ट्रिक एस्पिरेट (gastric aspirate) तकनीक का विशेष प्रशिक्षण दिया गया। इस अध्ययन में पाया गया कि प्रशिक्षण के बाद स्वास्थ्यकर्मी इस जांच विधि को नियमित रूप से अपनाने लगे और इसे अच्छी तरह स्वीकार भी किया गया। हालांकि, जांच से रोग की पुष्टि अपेक्षा से कम मामलों में हो सकी। अध्ययन के निष्कर्ष बताते हैं कि केवल प्रशिक्षण पर्याप्त नहीं है, बल्कि बच्चों में क्षय रोग की प्रभावी पहचान के लिए स्वास्थ्य सुविधाओं, उपकरणों, और पूरी जांच व्यवस्था को भी मजबूत बनाने की आवश्यकता है।

Author contributions

VMA: Formal analysis, manuscript writing; FK: Data curation, funding acquisition; PC: Supervision, project administration; AKS: Supervision; AJ: Conceptualisation, supervision and project administration. All authors have read and approved the final printed version of the manuscript.

Financial support and sponsorship

This implementation research was supported through The Global Fund to Fight AIDS, Tuberculosis and Malaria implemented through the Central TB Division, Directorate General of Health Services, Government of India and National Institute of Research in Tuberculosis, Chennai (Grant number - GF/001/IR_OR-003/2016-DBSR).

Conflicts of Interest

None.

Use of Artificial Intelligence (AI)-Assisted Technology for manuscript preparation

The authors confirm use of AI-assisted technology (ChatGPT version 4) for grammatical editing and paraphrasing of the manuscript, which was reviewed by the authors. No images were manipulated using AI.