Brief Answer:
Need investigations.

Detailed Answer:
Hello dear,

Prune belly syndrome is a congenital defect of abdominal wall muscle. So in these people abdominal muscles are absent. And these muscles are contributing in respiration especially in expiration.

And due to this defect there are certain modifications body does, to overcome the deficit by changes in sternum and vertebrae. So secondary changes in vertebrae and sternum can also affect respiration especially expiration.

So once you are exercising, your body needs for oxygen is increasing. So inspiration becomes fast. At the same time excess carbon dioxide developed in the body should be removed by expiration.
Since expiratory muscles are at fault in this syndrome the carbon dioxide is not fully expired and keep on accumulating.
And this triggers brain to increase respiratory rate (hyperventilation) to overcome high carbon dioxide.

So I advice to get arterial blood gas (ABG) analysis during exercise and check the CO2 levels.
In these kind of people chest physiotherapy with deep breathing exercise are useful.

Hope I have solved your query. I will be happy to help you further.

Wish you good health.

Thanks.

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Brief Answer:
Consult Pulmonologist and General Surgeon.

Detailed Answer:
Hello dear,

Thanks for your query on HCM.

In my opinion you should consult pulmonologist for respiratory problems.
And general surgeon for abdominal wall muscle defect.

The list of investigations helpful to you besides routine blood investigations are
1. ABG analysis.
2. Pulmonary function test (PFT)
3. Chest x ray.
4. Ultrasound abdomen
5. CT scan of abdomen.

Hope I have solved your query. If you are not having further queries please close the conversation and rate the answer.

Thanks.

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