Digital clubbing in children with complicated pulmonary hydatid disease: two case reports

Pulmonary hydatid cyst, caused by the larval stage of Echinococcus granulosus , remains an important pediatric parasitic infection in endemic regions. Complicated cysts may cause substantial morbidity through rupture, secondary infection, bronchial communication, or pleural involvement. Digital clubbing has rarely been reported in association with pulmonary hydatid disease and may complicate the diagnostic evaluation when it is the dominant clinical finding. We report two pediatric cases of complicated pulmonary hydatid disease associated with digital clubbing and characterized by distinct clinical courses. The first case involved a 6-year-old girl with a previous history of surgical removal of a pulmonary hydatid cyst who presented with a 10-day history of fever and cough. Progressive bilateral digital clubbing had developed during the interval after her previous surgery and preceded the current febrile respiratory episode. Contrast-enhanced computed tomography (CT) of the chest demonstrated pleural effusion and a complicated pulmonary hydatid cyst. Despite antimicrobial therapy and initiation of albendazole, the patient developed acute respiratory deterioration following a second bronchoscopy performed for persistent airway secretion management. Her oxygen saturation decreased to 46–50% despite reservoir mask oxygen therapy, requiring urgent endotracheal intubation and transfer to the pediatric intensive care unit. Emergency thoracic surgery resulted in rapid clinical improvement. The second case involved a 12-year-old girl in whom digital clubbing initially developed in the right hand and progressed bilaterally over approximately one year before definitive diagnosis. Because digital clubbing more commonly suggests chronic cardiopulmonary, inflammatory, or systemic disorders, pulmonary hydatid disease was not initially considered among the leading diagnostic possibilities. Further evaluation with chest CT revealed a 56 × 58 × 50 mm lesion in the apico-posterior segment of the left upper lobe containing internal air density with an air-crescent appearance, findings compatible with a complicated pulmonary hydatid cyst. Following diagnostic evaluation, the patient underwent left posterolateral thoracotomy and surgical excision of the cyst. Postoperative albendazole therapy was administered, and she was discharged in stable condition. At one-year follow-up, both patients remained clinically well without clinically apparent recurrence, although digital clubbing persisted and repeat chest imaging was unavailable. These two cases document digital clubbing in children with histopathologically confirmed complicated pulmonary hydatid disease, with contrasting clinical presentations and disease courses. The observed association does not establish a causal relationship. Both patients had favorable clinical outcomes at one-year follow-up, although digital clubbing persisted, and radiological resolution could not be confirmed because follow-up imaging was unavailable. In endemic regions, pulmonary hydatid disease should be considered in the differential diagnosis of unexplained digital clubbing, particularly when chest imaging is abnormal, while alternative causes are appropriately investigated.