Severity of CF

Question

If CF related liver disease or CF related diabetes occur at an early age (i.e. before the age of 4) does that influence survival?

Answer

Dearest,

Thank you for this important question. It is well known that progressive disease of the lungs is the most important determinant of survival in CF. Other organ disease such as liver disease and diabetes however contribute. Therefore your question is relevant.
CF liver disease is characterized by fibrosis or stiffening of the liver. Often this stiffening will not cause specific symptoms and the liver function (making specific proteins, detoxify) will remain good. The stiffening will however lead to difficulty in the passage of blood through the liver via the portal system. Therefore blood vessels can get engorged and the blood will search a way around the liver. Hereby varices can occur, for instance around the esophagus and the spleen will enlarge. The patient can bleed from these varices. Studies from many years ago demonstrate that children with CF liver disease will have a shorter life expectancy.

Over the years the treatment of CF has much improved and also the life expectancy has improved. More recent studies have demonstrated that, in children as well as adults, CF liver disease does probably not influence survival. Very recently there was a study where CF children with or without liver disease were compared. Both groups had similar lung function and a similar height and weight. Specific nutritional parameters such as measuring the thickness of the skin were however less good in the group with liver disease. In addition, a higher percentage of children with liver disease also suffered from diabetes. But over the 7 years in the study there was no difference in mortality between the 2 groups. The conclusion from this study is that children with CF liver disease do have a worse course of CF compared to children without liver disease. On the other hand a subgroup of children with CF liver disease as infants did no longer have CF liver disease as adults. This means that certain forms of liver disease can disappear later on.

Your second question concerns CF related diabetes. This form of diabetes mainly occurs from the age of 12 years on. Towards the 3rd decade, 20% of patients with CF will have CF related diabetes, with some studies showing even higher percentages. Multiple studies have demonstrated that CF related diabetes is associated with a faster progression of lung function deterioration and worse survival. Recent studies show that this is especially the case when diabetes is poorly controlled or insufficiently treated. CF related diabetes in principle does not occur before the age of 4 years.

We hope that this is sufficient answer to your question.

Best regards,

Prof. dr. M. Proesmans

05.08.2011