Our study found that almost half of the private health care providers investigating children for TB had used chest X-ray. Once suspected for TB many were diagnosed (79.7%). Many doctors referred presumptive TB cases to NTP for further diagnosis and management; private doctors who started TB treatment rarely (2.9%) reported the cases to NTP if they initiated treatment.
This study indicated that diagnosis of childhood TB by private providers was mainly based on clinical features, radiography and microscopy, rarely tuberculin skin tests, histopathology and Gene-Xpert MTB/RIF. Other settings also show that TB diagnosis in children is often based on a combination of clinical symptoms and chest X-ray; this could be due to the lack of a simple and precise diagnostic tool especially at the peripheral level, or due to inadequate training and capacity of health care workers[13–19]. However, in Pakistan, the availability of diagnostic tools varies across the country, where chest X-ray and smear microscopy are almost universally available and used for TB diagnosis at peripheral level. Histopathology, tuberculin skin test, sputum culture and Gene-Xpert MTB/RIF were only available at laboratories of tertiary care hospitals. Gene-Xpert MTB/RIF testing of stool of suspects has been shown to be useful to identify children with TB [20], and could be a good addition to traditional tests, but in Pakistan limited availability of the test in rural areas makes it currently less universal.
An important finding of the study was that private health care providers referred many children with presumptive TB: 3121 (47.9%) for diagnosis and 2443 (37.5%) for treatment; and they initiated treatment on only 14.6% of the diagnosed cases. Of all the referred presumptive TB cases 3812 (68.5%) were referred for diagnosis to district NTP centres; only 2.9% of the referred cases were registered in the NTP registers. This gap in reporting treatment outside the NTP system could be due to several factors: poor interdepartmental coordination between the laboratory and the treatment centres; inadequate counselling of presumptive TB patients by the laboratory technicians; weak referral mechanisms [21–24]. The linkages between laboratories and treatment centres could be improved with regular weekly visits by district health coordinator to laboratories, and contacting the referring private doctor to discuss further management according to NTP guidelines. Across Pakistan treatment services are also available in the public facilities that have diagnostic capacity. Perhaps due to lack of trust in public sector to provide quality care, few patients sought care in the public sector [6]. It is possible that some referred TB patients might not actually go to NTP, and perhaps received treatment in the private sector. A similar finding is also reported in a study from Indonesia, where only 2% of childhood TB cases recorded in hospital were reported to the NTP [25]. In Pakistan childhood TB is managed at various providers and various levels of the health care sector. There is an urgent need to improve linkages between NTP and other health care providers by engaging private sector through training and capacity building on national guidelines for managing childhood TB cases [26]. mHealth can potentially accelerate TB notification from the part of private sector that is not collaborating with NTP [27,28].
Almost all children had cough and fever and most had failure to thrive, which is consistent with the guidelines [26]. BCG vaccination is associated with decreased severity of tuberculosis[29] and BCG is part of child immunization program in Pakistan; absent BCG scar was more common in older children, which may reflect an improved Expanded Programme on Immunisation (EPI) program performance from 2012 to 2018; the percentage of fully immunized children aged 12-23 months increased from 54% in 2012-13 to 66% in 2017-18 [11]. Vaccination coverage inequalities exist at sub district levels, ranging from 58% to 85% in rural to urban areas and from 60% to 80% in lower to higher income quintiles [30].
In this study, we found that a higher proportion of adolescents reported respiratory symptoms, underwent sputum testing, and had more bacteriological confirmation. Adolescents are important for TB control and can contribute to substantial transmission in settings like schools. WHO suggests efforts to develop integrated family- and community-centered strategies to provide comprehensive and effective services at the community level to improve child and adolescents notification [31].
This study showed that failure to thrive and loss of body weight was more common in girls. This can be partly a biological difference and effect of culture and nutrition [32], but could also be partly because of confounding by age, as the girls diagnosed had a higher proportion of adolescents (28%) than the boys (16.9%). A study in India showed that the dietary intake of energy, iron, calcium and protein was significantly higher in boys than girls [33]. The slightly higher absence of BCG scar in girls could be explained by less care for girls in Pakistan, where a boy is usually more valued than girl. [34] Similar difference in non-utilization of child immunization are reported elsewhere. [35–37]. It may also be due to confounding by age, as the proportion of children with missing BCG scar is lower for younger than older children; hence a missing a scar was more common in adolescent girls, with a higher representation than boys.
Our study had several strengths. A major strength of this study is the large total sample with participants from all provinces, and we believe it may reflect the diverse situation in the country. In this study, validity of the data was ensured though data quality audit by crosschecking every record from the hard copies to remove inconsistencies. Also using mobile phone for data collection reduces data entry errors by eliminating one step for database creation. The study also had some limitations. Although a large total sample, the number of clusters was limited to the number of provinces, giving lower precision, but it probably reflects fairly well the different situations in the country. Also, our study did not include actual observations through field assessments; the accuracy and completeness of the data could therefore not be totally ensured. High referral to NTP centres for diagnosis may be partly because the study was closely related to NTP, and data collectors from NTP visited the study sites twice a month, and this could affect reporting, like a Hawthorne effect. The “yield” of childhood TB (79.7%) in this study was high compared to other settings ranging from 2.1% to 19% [38–41]. One possible reason of this high yield is that private providers may have recorded mostly already diagnosed child TB cases on the provided registers due to workload and may have missed an unknown number of other presumptive TB cases. The yield varied among the districts, which may reflect variation in completeness reporting all “suspects”. Future research is recommended to further assess and verify these findings in the field.