LPCDH diagnosed after 1 month shows the following three types of onset: (1) a congenital diaphragmatic defect that was not originally associated with organ herniation, with symptoms appearing when abdominal organs suddenly herniate due to increased abdominal pressure or other causes; (2) congenital herniation into the thoracic cavity, diagnosed when symptoms become apparent; and (3) asymptomatic and discovered incidentally on an examination.

In the present case, respiratory symptoms suggestive of bronchial asthma were noted before the onset of the disease, and the lungs were poorly expanded after repair of the diaphragm, suggesting that the intestinal tract had potentially congenitally herniated into the left thoracic cavity, and abdominal pain led to a definitive diagnosis.

The proportion of LPCDH to total CDH varies among reports [1,2,3,4], and this variation may depend on the accuracy of a prenatal diagnosis in the region and the investigation of the causes of neonatal deaths. The proportion of LPCDH to total CDH in the Japanese data reported in 2005 was only 2.6% [2], whereas a report from rural Egypt 2002 showed a very high incidence rate of 45.5% [4].

Bagłaj collected and reviewed 362 cases of LPCDH in 2004 [1]; 79.4% were left-sided, while 20.6% were right-sided, and 72% of left-sided cases were encountered before 1 year, compared with 87% at ≥ 1 year. The percentage of left-sided onset increased with age.

LPCDH presents with a wide variety of clinical manifestations (Table 1). In a previous review [1], 60% of patients on the left side had acute symptoms, 34% had chronic symptoms, and 6% were asymptomatic. In comparison, 32% had acute symptoms, 57% had chronic symptoms, and 11% were asymptomatic among right-sided LPCDH cases. Respiratory symptoms, such as tachypnea, cough, and recurrent airway infections, tend to be more common on the right side than on the left [2]. In contrast, gastrointestinal symptoms, such as abdominal pain and vomiting, were as common as respiratory symptoms on the left side. Gastrointestinal symptoms were less frequently recognized on the right side than on the left side, probably because the herniated liver prevented the prolapse of the intestinal tract. It is also important to note that in the left-sided cases, the frequency of an acute onset was as high as 82% in patients under 1 year [1]. In the present case, abdominal pain was the trigger for the diagnosis, but it is possible that asthma-like respiratory symptoms might be associated with CDH.

Hernia with sacs have been reported to be present in about 10% of cases of LPCDH [1, 2], with no apparent difference from CDH diagnosed in the neonatal period; the presence of a sac may thus have no influence on the presentation of CDH.

In the present case, poor expansion of the left lung after surgery showed gradual improvement over time. Postoperative echocardiography revealed no evidence of pulmonary hypertension. However, congenital pulmonary hypoplasia associated with CDH is expected to result in a relatively underdeveloped vascular bed. Pulmonary blood flow scintigraphy has been reported to help evaluate postoperative pulmonary blood flow in CDH operated in the neonatal period and is an indicator of functional prognosis [5, 6]. However, no reports have investigated the usefulness of pulmonary blood flow scintigraphy for LPCDH, and we did not perform it in the present case.

In recent years, laparoscopic or thoracoscopic surgery has become the surgical option of choice in an increasing number of LPCDH cases [7, 8]. Obata et al. reported little difference in outcomes between laparoscopic and thoracoscopic surgery but pointed out that the thoracoscopic approach may be superior in terms of technical difficulty and frequency of postoperative recurrence [9]. Since the patient presented with abdominal symptoms, we considered the need to search for abnormal findings of the abdomen other than the diaphragmatic hernia and attempted a laparoscopic procedure; however, the intestinal tract retracted back into the abdominal cavity, obstructing the view of the diaphragmatic defect.