The term Hermansky-Pudlak Syndrome (or HPS) is used to refer to a group of related metabolic genetic disorders. At the current time 9 subtypes of HPS have been identified and these are known as HPS-1, HPS-2, etc. Each subtype of HPS is caused by defects (or mutations) to a corresponding pair of genes. These genes are referred to as ‘the HPS-1 genes’, ‘HPS-2 genes’, etc. It is possible that other subtypes may be identified in the future. The term HPS will be used on this website to refer to all subtypes in general. Particular subtypes will be referred to when necessary.
Other characteristics of Hermansky-Pudlak Syndrome include.
Pulmonary fibrosis (or PF). HPS-1, HPS-4 and HPS-2 are strongly associated with pulmonary fibrosis. Approximately 80 percent of people with HPS-1 develop this. Pulmonary fibrosis causes scarring and stiffening of lung tissues It is a restrictive lung disease that makes it harder to breath and reduces the amount of oxygen that gets into the blood stream. It is life limiting. Some people with HPS-1 have had successful lung transplants. There is anecdotal evidence that a drug called Pirfenidone can slow down the progression of the disease. (Read more)
Inflammatory Bowel disease (or IBD). HPS-1 and HPS-4 are associated with an inflammatory bowel disease referred to as a ‘granulomatous Crohn-like colitis’. Granulomas are ulcers on the inside wall of the gut. It affects approximately 15 percent of people with HPS-1. There are a small number of HPS-3 cases who are affected by this. Some cases respond to drug therapies used to manage Crohn’s disease. Surgery is sometimes necessary were severe inflammation does not respond.. (Read more)
Renal (Kidney) failure and heart disease. There are a very small number of cases of renal failure (kidney disease) and cardiomyopathy (damage to heart muscle). It is not clear whether these are caused directly by HPS or are secondary to reduced levels of oxygen in the blood due to pulmonary fibrosis.
Immuno-deficiency.. HPS-2 is associated with the development of immuno-deficiency and pulmonary fibrosis during infancy and childhood. HPS-2 is extremely rare.with only 12 reported cases to date. (Read more)
HPS-3 is the most frequent subtype after HPS-1. There are no reported cases of HPS-3 were pulmonary fibrosis has occurred.
Other subtypes of HPS. The number of people known to have subtypes 5,6,7,8,and 9 is very small and many are still children. For these reasons it is not possible to predict possible future health problems.