The aim of this study is to determine the degree of agreement in cytokines level measured through BAL and those measured through salivary glands excretion.

and to compare the validity of cytokines in BAL versus salivary secretion in predicting the stage of ARDS and disease outcome in term of mortality, disease progression and length of stay.

• BAL will be performed by the attending pediatric intensivist in pediatric intensive care unit as part of standard care for ARDS management and Saliva samples will be collected non-invasively using sterile collection devices IL6 and TNF alfa will measured in both samples and compared to each other

Inclusion Criteria:

• Clinical diagnosis of Pediatric Acute Respiratory Distress Syndrome (ARDS)
• Age range: 1 month to 18 years
• Requirement for invasive mechanical ventilation
• Availability of salivary and bronchoalveolar lavage (BAL) samples within 24 hours of ARDS diagnosis
• Informed consent obtained from parent or legal guardian

Exclusion Criteria:

• Pre-existing chronic lung disease (e.g., cystic fibrosis, bronchopulmonary dysplasia)
• Known immunodeficiency or current immunosuppressive therapy
• Active malignancy or receipt of chemotherapy within the past 6 months
• Severe congenital anomalies incompatible with survival
• Refusal or inability to obtain informed consent

The study population will consist of pediatric patients diagnosed with mild to moderate acute respiratory distress syndrome (ARDS) who are admitted to the pediatric intensive care unit (PICU) and on mechanical ventilation to decrease the hazards of bronchoscopy on sever patients with ARDS

Individual participant data (IPD) will not be shared outside the primary research team