CRP16 A RARE CASE OF BRONCHIOLITIS OBLITERANS WITH PULMONARY-RENAL SYNDROME IN AN INFANT

Chiew Yee LAU 1,2, Azie Jumaatul Adawiyah NABIR 1,2, Aliyyah MOHAMMAD KHUZAINI1,2, Rahimah ISMAIL2
1 Paediatric Unit, Fakulti Perubatan Dan Sains Kesihatan, Universiti Sains Islam Malaysia, Nilai, Malaysia
2 Paediatric Department, Hospital Ampang, Ampang, Malaysia

Background
Bronchiolitis obliterans (BO) is a rare chronic pulmonary disorder in children. Its association with pulmonary-renal syndrome (PRS), involving concurrent pulmonary and renal dysfunction, is exceptionally uncommon in the paediatric population. 

Case presentation
A 14-month-old boy, born term with an uneventful perinatal history. He was first admitted for bronchopneumonia at 4-month-old. He required bilevel positive airway pressure (BiPAP) support for 10 days and subsequently weaned off oxygen after a total of 16 days of hospitalization. However, he was readmitted one week after discharge with similar symptoms and a more prolonged need for oxygen therapy.

His serial chest x-ray showed evidence of persistent right upper lobe collapsed, bilateral cystic changes. Further investigations including infective screening, nasopharyngeal aspirates and tuberculosis workup were negative. Echocardiography revealed a small atrial septal defect 0.3 centimeters without cardiac failure. A high-resolution Computed Tomography(CT) of thorax demonstrated bilateral fibrotic changes and peribronchial thickening consistent with BO. The patient was initiated on pulsed methylprednisolone therapy.

His persistent renal impairment was highlighted by a peak urea of 23.5mmol/L and creatinine of 123umol/L (baseline urea 10mmol/L, creatinine 90umol/L), while electrolytes remained within normal limits. Autoimmune screening (ANA, complement levels), immunodeficiency evaluations, and urinalysis were unremarkable. Kidney ultrasound with Doppler showed renal parenchymal disease without vascular abnormalities. 

Conclusion
This case illustrates the rare co-existence of BO with features of PRS in infancy, underscoring the importance of considering systematic involvement in persistent pulmonary disease. Early recognition, multidisciplinary evaluation, and long-term follow up are essential for management and prognostication in such complex cases.