Morgagni-Larrey Hernia: A Rare Cause of Pericardial Effusion

Left anterior congenital diaphragmatic hernia is a highly uncommon defect. In adults, its diagnosis is generally incidental, whereas in children, it frequently produces signs of respiratory disease. A 13-month-old boy, previously diagnosed as having a small ostium secundum atrial septal defect, was referred to our center to be studied because of poor echocardiographic visualization. The mother denied having any type of cardiorespiratory symptoms. The personal history of the infant included a postnatal diagnosis of Down’s syndrome (mosaicism) and congenital hypothyroidism, with hormone replacement therapy. He was in good general health, afebrile, and eupneic. Chest auscultation revealed rhythmic, although slightly muffled, heart sounds, in the absence of murmurs, and mild hypoventilation at the base of left hemithorax, with bowel sounds at that level. The echocardiographic study (Figure 1) showed anterior basal pericardial effusion of up to 17 mm during diastole, with no evidence of hemodynamic impact. The cardiac structures were displaced to the right, but had a normal configuration; it was not possible to obtain parasternal views. Plain chest x-ray (Figure 2) revealed the presence of air in left hemithorax that obscured the cardiac border, suggestive of anterior diaphragmatic hernia, which was confirmed by means of ultrasound and magnetic resonance imaging of chest and abdomen. Oral treatment with acetylsalicylic acid (100 mg/kg body weight/day) and methylprednisolone (an initial bolus of 2 mg/kg and 2 mg/kg/day thereafter) was initiated and was maintained for 1 week, resulting in a considerable improvement in the effusion (8 mm after 48 hours). The studies performed included differential blood cell count, blood chemistry, thyroid hormones, antinuclear antibodies, rheumatoid factor, Mantoux test, and serological testing for Echovirus, Coxsackievirus A and B, adenovirus, Influenza, Varicella, Epstein-Barr, and human immunodeficiency virus, with normal findings in every case. The effusion remained stable, and surgical repair of the hernia was carried out by means of laparotomy 3 weeks after the diagnosis, with very good results. There has been a progressive reduction of effusion (3 mm 6 months after surgical intervention). Congenital diaphragmatic hernia is an uncommon lesion (estimated prevalence, 1/2000 to 1/5000 live births). Morgagni hernia (anteriorly located) represents 3% to 5% of all of these hernias, and there is a clear predominance of the right parasternal position (at a ratio of 10:1), as the left side is protected by the pericardium.1 LETTERS TO THE EDITOR