Study team will perform a prospective, observational study in two sites in the Democratic Republic of Congo (DRC) and Bangladesh in children aged 3 months to 14 years, admitted to hospital with acute respiratory symptoms. The Kinshasa lung ultrasound (K-LUS) approach integrates existing WHO clinical guidelines, lung ultrasound diagnostic accuracy evidence and paediatric ultrasound guidelines. The approach was built using a modified Delphi technique and integrates six LUS profiles, two clinical history features (timing of onset, trauma) and one clinical examination feature (fever) to suggest one among 10 clinical diagnosis. After the initial diagnosis is established by the treating physician, a research assistant will perform a LUS examination and apply the K-LUS approach. Comparison between the K-LUS derived diagnosis and the clinical diagnosis will be performed. After patient discharge a panel will also establish the most likely diagnosis according to all information available during patient stay.

This study is funded by the Wellcome Trust (ITPA grant) ref: WT-ITPA 2021/001

Acute respiratory distress represents one of the main reasons for hospital admission in low and middle income countries. Prompt and accurate diagnosis of the underlying pathological process is crucial to guide appropriate management. Lung Ultrasound (LUS) is an innovative, non-invasive, low-cost, point-of-care tool with high diagnostic accuracy for acute pulmonary diseases. It is a superior alternative to chest radiography (CXR), which is costly and seldom available in low-resource hospitals. To date, we lack a validated LUS-enhanced paediatric diagnostic approach specifically designed for low-resource settings. The primary objective is to test whether a paediatric diagnostic algorithm integrating key elements of patient history, the presence of fever and a systematic bedside LUS examination, changes the admission diagnosis. We also seek to describe the frequency of predefined suspected diagnoses observed and semiquantify pulmonary aeration in children admitted with respiratory symptoms. We will perform a prospective, two-center observational study in the Democratic Republic of Congo (DRC) and Bangladesh in children aged 3 months to 14 years, admitted to hospital with acute respiratory symptoms and signs. The 'Kinshasa lung ultrasound' diagnostic approach (K-LUS) was developed by a group of paediatric clinical and imaging experts based on existing WHO clinical guidelines, published LUS evidence-based frameworks, primary LUS literature on single pathologies and existing paediatric point of care ultrasound guidelines. After the initial diagnosis is established by the treating physician, a research assistant will perform a LUS examination and apply the K-LUS approach, to observe whether there is a change in the initial diagnosis. This is a purely observational study and no intervention will be applied, neither will the patient treatment be changed in relation to the study. The integration of LUS in the diagnostic approach of the critically ill paediatric patient has the potential of improving outcomes and appropriateness of care. It could provide earlier and low-cost diagnosis in both district and referral hospitals, with a potential expansion to peripheral healthcare facilities and integration in existing integrated management of childhood illness (IMCI) guidelines. Such an approach would also help allocate scarce resources by limiting second line radiological imaging techniques only to patients in need.

Inclusion Criteria:

• Children aged between 3 months and 14 years;
• Admitted to the emergency department or ward with cough or difficulty in breathing;

Exclusion Criteria:

• Expected short stay in the emergency department (< 6h)
• Emergency transfer to other facilities
• Refusal of informed consent by attending parent or caregiver, as appropriate
• Lung ultrasound not feasible (e.g. non-availability of a trained physician)

Infants and children aged 3 months old to 14 years old presenting with cough or difficulty in breathing.

With participant's consent, data from this study may be shared in a de-identified form with other groups or researchers in accordance with the MORU Data Sharing Policy (http://www.tropmedres.ac/data-sharing-policy).

Refer to MORU data sharing policy with other researchers to use in the future. https://www.tropmedres.ac/units/moru-bangkok/bioethics-engagement/data-sharing/moru-tropical-network-policy-on-sharing-data-and-other-outputs