Abstract Introduction Cerebrospinal fluid (CSF) hydrothorax is a rare complication of ventriculoperitoneal (VP) shunting, usually due to shunt dysfunction or migration. In infants, transdiaphragmatic CSF leakage into the pleural space is exceptionally uncommon and may occur without overt shunt issues. We report a 7-month-old former 25-week preterm infant with right-sided CSF hydrothorax in the absence of infection or shunt malfunction. Case Description A 7-month-old male born at 25 weeks’ gestation with bilateral grade IV intraventricular hemorrhage, post-hemorrhagic hydrocephalus status post endoscopic third ventriculostomy (ETV) and VP shunt, retinopathy of prematurity, and small patent ductus arteriosus/foramen ovale, presented with several months of dry, movement-related, non-paroxysmal cough since NICU discharge. He was afebrile and feeding well. Chest radiograph showed a right pleural effusion (PE), prompting admission. Exam revealed diminished breath sounds over the right lower lung field without distress. Laboratory studies (CBC, CMP, CRP, ESR, viral panel) were unremarkable. Chest ultrasound confirmed a moderate PE. A pigtail catheter drained 11 mL of yellow serosanguineous fluid initially, followed by 30-60 mL serous fluid daily. Fluid analysis indicated a transudate (protein 3 g/dL, triglycerides 23 mg/dL, normal LDH, 91% monocytes/macrophages). Cultures and cytology were negative. CT chest/abdomen/pelvis and echocardiogram confirmed intact shunt, no intra-abdominal fluid, mass, or cardiac abnormality. Beta-2 transferrin assay was positive, confirming CSF in the pleural space. Neurosurgery determined likely translocation through a small peritoneal-pleural communication or diaphragmatic defect rather than shunt dysfunction. Pediatric surgery recommended observation. The chest tube was clamped, output declined, and it was removed after 24 hours without recurrence. The patient remained asymptomatic and was discharged in stable condition. Discussion CSF hydrothorax without shunt migration is a rare cause of pediatric PE, often from diaphragmatic microdefects or pressure-mediated transdiaphragmatic flow. Diagnosis requires suspicion and confirmation with beta-2 transferrin. Multidisciplinary evaluation and conservative management can suffice in stable cases. Conclusion This case highlights the importance of considering CSF hydrothorax in infants with unexplained PE and VP shunt history. Early recognition and collaborative management can prevent unnecessary interventions and guide appropriate care. This abstract is funded by: none
Hassouba et al. (Fri,) studied this question.