Eventration of the right hemidiaphragm with multiple associations: A rare presentation.

Sir,

Eventration of the diaphragm is mostly a congenital anomaly, where it is partly or wholly replaced by a fibrous sheet.[1] The reported incidence of the disorder in adults is about 1:10,000. It usually occurs as an isolated entity and is extremely rare to occur bilaterally, almost always presenting in infancy with respiratory compromise, and is associated with a high mortality rate.[2] More commonly, it occurs unilaterally, mostly on the left side, and may present at any age and has a male predominance. Complete eventration on the right side should be extremely uncommon in adults as only a few reports are available in the English literature.[34] We are presenting such a case in an adult male who presented to us with recurrent pneumothorax due to uncontrolled asthma. Further evaluation revealed multiple associations, i.e. lower lobe hypoplasia, a supero–posteriorly placed deformed liver with an aberrant venous drainage and block D4-D5 vertebra, which to the best of our knowledge is the first case of right-sided eventration with multiple associations.

LR, a 22-year-old male student, presented in the emergency area of this hospital with acute onset of shortness of breath (SOB) and pain chest of 3 h duration. Initial evaluation revealed him to be a known case of bronchial asthma, poorly controlled on oral medication and having two episodes of right-sided pneumothorax, successfully managed with inter-costal chest tube drainage (ICTD), in the past 3 months. He was a normally born child with normal life milestones. There was no history of any infection, trauma or malignancy in the past. He had never smoked, was a teetotaler and never took any drugs, other than the asthma medication. Nothing significant was recorded in the family history.

The patient was fairly built and adequately nourished. His respiratory rate was 36/min, pulse rate was 120/min and regular, temperature was 99°F, blood pressure was 100/60 mmHg and peripheral oxygen saturation was 80%. Trachea and apex beat were shifted to the left. The chest was hyper-inflated and hyper-resonant on the right side, along with decreased movements, vocal fremitus and breath sounds. Left-sided chest revealed extensive rhonchi. Examination of the other systems revealed nothing abnormal.

A skiagram chest PA view of the patient was suggestive of right pneumothoax. The patient was given oxygen along with standard asthma therapy and an ICTD was established, after which he improved. A repeat skiagram chest PA view, post ICTD, showed complete expansion of the lung on the right side along with a normally placed trachea and heart, but the right hemidiaphragm was raised up to the level of the 3rd intercostal space.

Routine blood counts, renal functions and liver function tests were within normal limits. Mantoux skin test was negative. Pulmonary function tests revealed a moderate obstructive defect.

Ultrasonography showed that the right hemidiaphragm had been replaced by a thin, fibrous sheet with reduced excursion, but was continuous and devoid of any paradoxical movements. Sniff test on fluoroscopy in erect position confirmed lack of paradoxical movements. Computerized tomography of the thorax showed that the right hemidiaphragm was thin and grossly elevated [Figure 1], the lower lobe of the right lung was hypoplasic [Figure 2], the liver was deformed [along with an anomalous venous drainage [Figure 3] and the 4th and 5th vertebral bodies were fused.

Figure 1

Tomogram of the patient, post intercostal chest tube drainage, showing complete expansion of the lung along with raised hemidiaphragm on the right side. The right lower lobe is small in size

Figure 2

Computerizd tomography image at the level of carina (lung window) showing very small-sized lower lobe due to hypoplasia of the lung on the right side

Figure 3

Contrast-enhanced sagittal computerized tomography image showing the deformed liver with hepatic veins joining each other in the liver parenchyma to form an arc-like vessel (arrow)

After about 1 week of treatment in the hospital, the patient was discharged on standard asthma medication with the advice to remain under regular follow-up.

In the present case, the right hemidiaphragm had retained its continuity and attachments to the costal margins, ruling out diaphragmatic hernia,[5] and a negative sniff test had ruled out diaphragmatic paralysis.[6] Thus, the diagnosis of complete eventration of the right hemidiaphragm was comprehensively established.

Associated ipsilateral organ anomalies have been described in the medical literature along with left-sided eventration. These include wandering spleen syndrome and gastric volvulus.[1789] Right-sided dextrogastria and volvulus have also been described in an infant.[3] In adults, only a single case report of right-sided eventration has been reported,[4] but it was an isolated event. Ours is possibly the first case of right-sided eventration with multiple associations, i.e. lung, liver and vertebral anomalies.

Why deformation of the organs should occur on the side of eventration is a matter of research. Par et al.[7] had postulated that wide sub-diaphragmatic space left due to an elevated hemidiaphragm provided adequate space for malformation of the subdiaphragmatic structures to occur, but this fails to explain the multiple associations as were seen in our case. We are reasoning that as a result of eventration, pressure differential across that side of the diaphragm is mostly lost. The altered pressures adversely affect the developmental process, i.e. malformation of the organs, on that side of the chest. Absence or weakness of supporting ligaments may contribute to other associations, i.e. gastric volvulus and wandering spleen.[789]

Eventration-associated anomalies are mostly of no serious consequence, as was in our case. But, acquired pathologies in these organs may present with atypical clinical manifestations, making its recognition difficult, and prior knowledge of these anomalies should be of great help in such situations.