Right-Sided Bochdalek Hernia Appearing as a Cavitary Lung Mass

Abstract

INTRODUCTION: Bochdalek hernia was first described in 1848 and has since remained and uncommon finding in adults. With about 150 adult cases reported, right-sided Bochdalek hernia in adults is especially rare. We herein report a case of right sided bochdalek hernia in an adult, who presented with hypoxemia, lethargy and a right sided 'cavitary lung mass'. 'Cavitary mass' was later found to be a Bochdalek hernia that was repaired successfully. CASE PRESENTATION: 69-year-old man presented with shortness of breath and lethargy. He was diagnosed with Hypertension, Chronic obstructive pulmonary disease, schizophrenia and dementia for which he is being treated. He was unable to give a history because of dementia however, additional information obtained from relatives noted a history of recurrent vomiting. There was no fever, cough or abdominal pain. He was dehydrated, hypotensive (systolic blood pressure-78mmhg) and hypoxemic (saturation of 84% -ambient air). He had tachypnea (21breaths/minute) and decreased air entry in the right lung base. Bowel sounds were normal with no abdominal distention or tenderness. Investigations showed Anemia (Hb-9g/dl), hypernatremia (147mmol/l), BUN (45mg/dl) and Creatinine (2.2mg/dl). Other laboratory tests were normal. A right-sided 'cavitary mass' was seen on posterior - anterior chest radiograph (Fig 1). A nasogastric tube passed was found to coil up in the chest (Fig 2) and CT scan obtained to evaluate this finding revealed a right sided Bochdalek hernia. Hernia repair was by abdominal laparoscopy and a Large hernia defect of about 6 -7 cm containing stomach was found. Surgery and recovery was uneventful with resolution of hypoxemia, lethargy and vomiting. DISCUSSION: Bochdalek hernia is found predominantly in pediatric age and occurs because of in-utero failure of fusion of the posterior-lateral diaphragmatic foramina. It is rare in adults with a reported incidence of 0.17%. It may present with signs of incarcerated bowel and severe pulmonary disease. Diagnosis with plain chest radiography may be misleading and may suggest other intra-thoracic pathology. Although the sensitivity of chest CT for diagnosis of right sided hernia is noted to be lower compared to left sided hernias, CT scan still remains more sensitive than the plain chest radiography. CONCLUSIONS: Bochdalek hernias in adults may be misdiagnosed as primary lung lesions and should be suspected in patients with evidence of suggestive pathology on chest radiograph and unexplained intra-abdominal symptoms as in our case. Plain radiographs may be used for screening but CT is more sensitive. Treatment is by laparoscopic surgery which offers good outcome.